CD38 modulating antibody

Abstract

To provide anti-CD38 antibodies that may be used in the treatment of cancer, particularly solid and hematological cancers.SOLUTION: Provided is an anti-CD38 antibody having a particular sequence, or antigen-binding fragment thereof, the anti-CD38 antibody or antigen-binding fragment thereof exhibiting antibody-dependent cell-mediated cytotoxicity (ADCC) activity against CD38+ target cells, exhibiting no complement dependent cytotoxicity (CDC) or reduced CDC activity against CD38+ target cells as compared to Daratumumab under the same or substantially the same conditions, and inducing immune effector cell activation.SELECTED DRAWING: Figure 20

Description

[Background technology]

[0001] CD38 is a type II membrane receptor glycoprotein with enzymatic activity, specifically as a key ADP-ribosyl cyclase that produces cyclic adenosine diphosphate ribose (cADPR) from nicotinamide adenine dinucleotide. CD38 can also hydrolyze NAD+ to ADPR. ADPR generation can modulate immune responses, as ADPR is upstream of the pathway that leads to the production of immunosuppressive adenosine. Different extracellular stimuli can induce cADPR production. cADPR is important for mobilizing intracellular calcium stores, which are involved in many cellular functions, such as cell proliferation, differentiation, adhesion, and signal transduction. Although initially identified as a leukocyte activation marker, CD38 plays a dual role as a receptor and ectoenzyme, to which cell signaling and cell homeostasis activities are contributed. CD38 has been associated with various human diseases, including malignancies such as chronic lymphocytic leukemia, myeloma, and ovarian cancer (Quarona V,et al.,2013, Wei W,et al.,2014).

[0002] CD38 is found on the surface of many cell types involved in the immune response (briefly called immune cells), including effector cells such as T and B lymphocytes and NK cells, but also immunosuppressive cells such as regulatory T and B cells, myeloid-derived suppressor cells (MDSCs), or tumor-associated macrophages (Chevrier S et al. 2017). For example, in lung cancer patients, anti-PD-1 treatment induced the proliferation of PD-1-expressing T cells that expressed high levels of CD38 (Kamphorst AO et al., 2017). The importance of cADPR- and CD38-mediated Ca2+ signaling for the biological activity of immune cells, specifically for the regulation of immune responses under physiological and pathological conditions, has been described in the literature (Morandi F et al., 2015, Rah SY et al., 2015).

[0003] CD38 is highly expressed by cancer cells in multiple myeloma patients of all stages and in CLL patients with poor prognosis. Various CD38-targeted therapies have been developed, mainly by generating compounds that act as CD38 antagonists or inhibitors (de Weers M et al., 2011; van de Donk NW et al., 2016; Horenstein AL et al., 2017). Anti-CD38 monoclonal antibodies (such as those named IB4) that act as CD38 agonists are also characterized by, among other activities, the induction of calcium ion mobilization, CD38 shedding, NK cell-mediated cytotoxicity, cytokine secretion (specifically interleukin 6 and interferon gamma), and proliferation of human T lymphocytes, and have been modified to deliver immunotoxins (Malavasi F et al., 2008; Hara-Yokoyama M et al., 2008; Frasca L et al., 2013). Such positive effects on immune cells may be related to Ca2+ mobilization, inhibition of CD38 enzymatic activity, and / or induction of activation of intracellular signaling pathways.

[0004] Monoclonal antibodies have been developed for targeted direct killing of CD38-expressing tumor cells and have shown promising results in clinical trials. However, the activity of such anti-CD38 antibodies may be restricted to tumors where CD38 is highly expressed on the surface of cancer cells. In solid tumors, CD38 expression is generally lower or absent on tumor cells and may be associated with tumor-infiltrating immune cells, both effector and inhibitory. Thus, we present the activity and compatibility with drug development derived from the combination of different components, such as CD38-specific agonistic or regulatory properties and targeted cell killing or activation, for the treatment of cancer, specifically solid and hematological cancers. There remains a need for available anti-CD38 antibodies. Summary of the Invention

[0005] In some embodiments, the present invention provides novel CD38 modulating antibody agents. In some embodiments, the CD38 modulating antibody agents provided are antibodies or antigen-binding fragments that bind specifically to CD38, particularly to human CD38, and in many embodiments to a site within the extracellular domain of human CD38.

[0006] In some embodiments, the provided antibodies or antigen-binding fragments modulate one or more characteristics of CD38. That is, in some embodiments, the level and / or activity of CD38, and / or one or more downstream effects thereof, are detectably altered in the presence of the provided antibody compared to the absence of the provided antibody. Alternatively, or in addition, in some embodiments, the level and / or activity of CD38, and / or one or more downstream effects thereof, in the presence of the provided antibody, is comparable to or exceeds that observed under comparable conditions in the presence of a reference CD38 modulating antibody agent (e.g., a reference anti-CD38 antibody, such as IB-4, having a known desirable attribute, e.g., a known ability to stimulate one or more characteristics of CD38)

[0007] In many embodiments, one or more characteristics of CD38 are enhanced in the presence of a provided CD38 modulating antibody agent (e.g., an anti-CD38 antibody or antigen-binding fragment thereof). For example, in some embodiments, the presence of a provided CD38 modulating antibody agent (e.g., an anti-CD38 antibody or antigen-binding fragment thereof) correlates with increased immune cell activation and / or proliferation. Thus, the provided CD38 modulating antibody agent is often referred to herein as an "agonist". However, one skilled in the art will understand that the teachings of the present disclosure are not limited to a particular mechanism of action of the provided antibody or antigen-binding fragment thereof. The relevant structural and / or functional characteristics of the provided antibodies are described herein and are self-evident.

[0008] In some embodiments, the provided CD38 modulating antibody agents (e.g., CD38 antibodies or antigen-binding fragments) may be characterized, for example, by their effect on certain immune effector cells (e.g., NK cells and / or T cells). Alternatively, or in addition, in some embodiments, the provided CD38 modulating antibody agents (e.g., CD38 antibodies or antigen-binding fragments) may be characterized, for example, by their effect on immunosuppressive cells. For example, in some embodiments, the provided CD38 modulating antibody agents exhibit activating properties on immune effector cells, such as NK cells and T cells, and / or cytotoxic properties on highly CD38 expressing cells, such as immunosuppressive cells or tumor cells (e.g., in either case expressing CD38 on their surface). Alternatively, or in addition, in some embodiments, the provided CD38 modulating antibody agents are characterized by one or more features related to binding to a particular epitope within the human CD38 extracellular domain and / or that make them particularly amenable to pharmaceutical use and / or manufacture.

[0009] The provided technologies, including the provided CD38 modulating antibody agents (e.g., the provided antibodies or antigen-binding fragments thereof (or variants thereof)), compositions comprising them, and / or their uses, are useful in medicine. In some embodiments, such provided technologies are useful in cancer therapy and / or prevention.

[0010] In one aspect, an anti-CD38 antibody or antigen-binding fragment thereof (or variant thereof) is provided, the antibody or fragment thereof comprising: - exhibits antibody-dependent cell-mediated cytotoxicity (ADCC) activity against CD38+ target cells; - exhibits no complement-dependent cytotoxicity (CDC) activity against CD38+ target cells or exhibits reduced CDC activity compared to daratumumab under the same or substantially the same conditions; -Induce immune effector cell activation.

[0011] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof having the above characteristics is, or is derived from, e.g., aCD38-a-323, aCD38-b-329, aCD38-b-348, or aCD38-a-306. The antibody or antigen-binding fragment thereof having the above characteristics may be, or may be derived from, aCD38-a-327.

[0012] The antibody-dependent cell-mediated cytotoxicity (ADCC) activity of an anti-CD38 antibody or antigen-binding fragment thereof can be determined in vitro using the assay described in the Examples, for example, using CD38+ Daudi cells as target cells and human PBMC cells as effector cells, with a target cell to effector cell ratio of about 50:1 to about 25:1.

[0013] Complement-dependent cytotoxicity (CDC) activity against CD38+ target cells can be determined in vitro using the assay described in the Examples, for example, using CD38+ Daudi and / or Raji cells in the presence of 10% complement. CDC activity can be determined by treating target cells with increasing antibody concentrations up to 10 μg / mL in the presence of human complement. In some embodiments, CDC activity is determined by measuring the maximum cell lysis percentage of CD38+ cells, i.e., CD38+ Daudi cells, in the presence of 10% complement. The maximum lysis of a given antibody can vary between experiments. Therefore, it is beneficial to consider other metrics for measuring CDC activity, including, for example, EC50 values ​​and / or fold difference in maximum lysis % and / or EC50 compared to a reference antibody (such as daratumumab). Thus, the determination of lower CDC activity compared to daratumumab can refer to the maximum lysis %, EC50, and / or fold change compared to daratumumab at any value.

[0014] In a preferred embodiment of the invention, the CD38 modulating antibody agent provided does not exhibit CDC or does not exhibit CDC, a) an EC50 that is at least 0.5-fold higher (or more preferably at least 1-fold higher) than daratumumab, or b) exhibits a maximal % lysis measured in Raji cells and / or Daudi cells in the presence of 10% complement that is less than or equal to half the maximal % lysis exhibited by daratumumab.

[0015] Needless to say, the CDC of daratumumab is determined under the same or substantially the same conditions for comparison. Such anti-CD38 antibodies or antigen-binding fragments thereof can be, or can be derived from, for example, aCD38-a-323, aCD38-b-329, aCD38-b-348, aCD38-a-306, or aCD38-a-327. CDC activity can be determined using an antibody concentration of up to about 10 μg / mL. Those skilled in the art will understand that when determining maximum cell lysis, a concentration of 10 μg / mL is not necessarily required, since maximum cell lysis can occur at lower antibody concentrations, but 10 μg / mL can be used as needed.

[0016] In some embodiments, the reduced CDC activity compared to daratumumab is indicative of the EC 50 However, the EC of daratumumab under the same or substantially the same conditions 50 at least about 0.5 times higher (i.e., at least about 1.5 times higher), or preferably Preferably, the EC of the antibody or antibody-binding fragment thereof is at least about 1-fold higher (i.e., at least about 2-fold higher). 50 The EC value of daratumumab against Daudi cells and / or Raji cells in the presence of 10% complement 50 In some such embodiments, an anti-CD38 antibody or antigen-binding fragment thereof having such characteristics may be, or may be derived from, e.g., aCD38-b-348.

[0017] In some embodiments, the reduced CDC activity compared to daratumumab is such that the maximum lysis % is less than or equal to half of the maximum lysis % exhibited by daratumumab under the same or substantially the same conditions. For example, the maximum lysis % may be less than or equal to half of the maximum lysis % exhibited by daratumumab measured in Raji cells and / or Daudi cells in the presence of 10% complement. In some such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof having such characteristics may be, or may be derived from, e.g., aCD38-a-323 or aCD38-a-306.

[0018] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof (or a variant thereof) does not exhibit CDC. In some such embodiments, an anti-CD38 antibody or antigen-binding fragment thereof having such characteristics may be, or may be derived from, e.g., aCD38-a-327.

[0019] In some embodiments, the antibody or fragment thereof (or variant thereof) causes less than 60% lysis of CD38+ expressing Daudi cells by CDC. In some embodiments, the antibody or fragment thereof causes less than about 50%, less than about 40%, less than about 30%, or less than about 20% lysis of CD38+ expressing cells by CDC. In some embodiments, the antibody or fragment thereof causes less than about 60% lysis of CD38+ expressing cells by CDC, but more than about 10% lysis. The lysis percentage can be measured in Daudi cells in the presence of 10% complement with increasing antibody concentration up to 10 μg / mL. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof having the above characteristics can be, or can be derived from, e.g., aCD38-a-323 or aCD38-a-306.

[0020] In some embodiments, the antibody or antigen-binding fragment thereof (or variant thereof) has an EC of at least about 0.05 μg / mL against CD38+ Daudi cells and / or Raji cells. 50Such an anti-CD38 antibody or antigen-binding fragment thereof having an EC50 value of at least about 0.05 μg / mL on CD38+ Daudi cells and / or Raji cells can be, or can be derived from, e.g., aCD38-a-323, aCD38-b-348, or aCD38-a-306. In some embodiments, the antibody or fragment thereof induces CDC with an EC50 of at least about 0.05 μg / mL, at least about 0.10 μg / mL, or at least about 0.15 μg / mL on CD38+ Daudi cells and / or Raji cells (and optionally causes less than 60% lysis of such CD38+ expressing cells by CDC at antibody concentrations up to about 10 μg / mL). The anti-CD38 antibody or antigen-binding fragment thereof having an EC50 value of at least about 0.15 μg / mL against CD38+ Daudi cells and / or Raji cells includes an antibody or fragment thereof that is aCD38-b-348 or aCD38-a-306.

[0021] In some embodiments, the antibody is or is derived from aCD38-b-348. Such antibodies exhibit antibody-dependent cell-mediated cytotoxicity (ADCC) activity against CD38+ target cells and have a C10A1-mediated cytotoxicity (C10A1-mediated cytotoxicity) activity against CD38+ target cells compared to daratumumab under the same or substantially the same conditions. exhibit reduced CD4 activity against CD38+ target cells (e.g., the EC50 value measured as described herein may be at least twice the EC50 value of daratumumab), induce immune effector cell activation, induce T cell proliferation, induce increased cytokine secretion including IL-2, IFNγ, TNFα, GM-CSF, and IL-10, and induce NK cell activation. Such antibodies may also exhibit a slight inhibitory effect on CD38 cyclase activity.

[0022] In some embodiments, the antibody is or is derived from aCD38-a-323. Such antibodies exhibit antibody-dependent cell-mediated cytotoxicity (ADCC) activity against CD38+ target cells, exhibit reduced CDC activity against CD38+ target cells compared to daratumumab under the same or substantially the same conditions (e.g., the maximal lysis % measured as described herein may be less than half of the maximal lysis % of daratumumab), induce immune effector cell activation, induce T cell proliferation, induce increased cytokine secretion including GM-CSF, exhibit an inhibitory effect on CD38 NADase activity, and exhibit a stimulatory effect on CD38 cyclase activity.

[0023] In some embodiments, the antibody is or is derived from aCD38-b-329. Such antibodies exhibit antibody-dependent cell-mediated cytotoxicity (ADCC) activity against CD38+ target cells, exhibit reduced CDC activity against CD38+ target cells compared to daratumumab under the same or substantially the same conditions, induce immune effector cell activation, induce T cell proliferation, and induce increased cytokine secretion including IL-2, TNFα, GM-CSF, and IL-10.

[0024] In some embodiments, the antibody is or is derived from aCD38-a-306. Such antibodies exhibit antibody-dependent cell-mediated cytotoxicity (ADCC) activity against CD38+ target cells, exhibit reduced CDC activity against CD38+ target cells compared to daratumumab under the same or substantially the same conditions (e.g., the % maximum lysis measured as described herein may be less than half of the % maximum lysis of daratumumab), induce increased T cell proliferation, induce increased cytokine secretion including IL-2, TNFα, IFNγ, and IL-10, induce immune effector cell activation, and exhibit inhibitory effects on CD38 NADase activity and CD38 cyclase activity.

[0025] In some embodiments, the antibody is or is derived from aCD38-a-327. Such antibodies exhibit antibody-dependent cell-mediated cytotoxicity (ADCC) activity against CD38+ target cells, exhibit reduced CDC activity (or in fact no CDC activity) against CD38+ target cells compared to daratumumab under the same or substantially the same conditions, can induce T cell proliferation (or in some embodiments no T cell proliferation), can induce immune effector cell activation (or in some embodiments no T cell proliferation), and exhibit an inhibitory effect on CD38 cyclase activity.

[0026] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof (or variant thereof) exhibits antibody-dependent cellular phagocytosis (ADCP) against CD38-expressing cells. In such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof can be, for example, aCD38-b-348 or can be derived therefrom. ADCP activity can be determined by a reporter cell assay measuring FcgRIIa binding in Jurkat cells as effector cells expressing FcgRIIa. The effector cells also express NFAT-inducible luciferase. The target cells in this assay can be CD38-expressing Raji cells. NFAT signaling can be measured to determine activity.

[0027] In some embodiments, an anti-CD38 antibody or antigen-binding fragment thereof (or a barrier The antibodies can induce ADCP on in vitro generated regulatory T cells, which can be measured as discussed in the Examples.

[0028] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof (or variant thereof) does not exhibit ADCP activity against CD38-expressing cells, e.g., as determined in a reporter cell assay in which the ADCP measures FcgRIIa binding. In such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof can be, or can be derived from, e.g., aCD38-a-323 or aCD38-a-306.

[0029] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof (or variant thereof) induces a higher amount of T cell activation compared to daratumumab under the same or substantially the same conditions. In some embodiments, T cell activation is determined by measuring NFAT signaling in luciferase reporter Jurkat cells. In some embodiments, the NFAT signaling induced by the anti-CD38 antibody or antigen-binding fragment thereof measured in luciferase reporter Jurkat cells is at least about 10% higher than the NFAT signaling of daratumumab measured under the same or substantially the same conditions. In some embodiments, the NFAT signaling is at least about 15%, at least about 20%, or at least about 30% higher than the NFAT signaling of daratumumab measured under the same or substantially the same conditions.

[0030] In a NFAT luciferase reporter assay in Jurkat cells, NFAT signaling can be measured in relative luminescence units (RLU) in the presence of a soluble CD3 monoclonal antibody. The CD3 monoclonal antibody can be at a concentration of 1 μg / mL, and Jurkat cells can be stimulated with an anti-CD38 antibody at a concentration of about 5 μg / mL to about 40 μg / mL (e.g., 10 μg / mL). Using such an assay, NFAT signaling can be at least about 30% higher than NFAT signaling of daratumumab measured under the same or substantially the same conditions when the RLU of stimulation with CD3 alone is used as a baseline.

[0031] T cell activation may be further characterized by increased T cell proliferation and / or increased cytokine secretion, which may be selected from the group consisting of IL-2, TNF-α, IFN-γ, IL-10, and GM-CSF.

[0032] T cell proliferation can be measured, for example, as determined in the presence of an antibody concentration of 10 μg / mL and 0.1 μg / mL or 0.5 μg / mL of anti-CD3 antibody after 72 hours of incubation, as seen in the Examples. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof increases T cell proliferation of CD4+ cells and / or CD8+ cells by at least about 20% compared to untreated cells. In some embodiments, T cell proliferation is increased by at least about 25%, at least about 30%, at least about 35%, or at least about 40% compared to untreated cells.

[0033] Preferably, the anti-CD38 antibody or antigen-binding fragment thereof (or variant thereof) increases T cell proliferation in CD4+ cells and / or CD8+ cells by at least about 0.5-fold (i.e., at least 1.5-fold), or at least 1-fold (i.e., at least 2-fold), or at least 2-fold (i.e., at least 3-fold), or at least 3-fold (i.e., at least 4-fold) compared to cells treated with human IgG1 under the same or substantially the same conditions (e.g., 72 hours of incubation at the same antibody concentration).

[0034] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof (or variant thereof) exhibits a greater than that induced by daratumumab under the same or substantially the same conditions. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof increases the secretion of GM-CSF compared to daratumumab. In such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof can be or can be derived from, for example, aCD38-a-323, aCD38-b-329, or aCD38-b-348. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof, for example, aCD38-a-323, aCD38-b-329, aCD38-a-327, or aCD38-b-348, increases the secretion of IL-2 compared to daratumumab. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof increases secretion of IL-2, TNF-α, IFN-γ, IL-10, and GM-CSF compared to daratumumab. In such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof can be, or can be derived from, e.g., aCD38-b-329 or aCD38-b-348. Cytokine secretion can be measured, e.g., as determined at an antibody concentration of 10 μg / mL after 72 hours of incubation, as provided in the Examples.

[0035] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof (or variant thereof) induces NK cell activation. In such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof may be, for example, aCD38-b-348 or may be derived therefrom. NK cell activation may be characterized by an increase in NK cell proliferation. Alternatively, or in addition, NK cell activation may be determined by an increase in intracellular IFNg production and / or an increased expression of the degranulation marker CD107a, indicative of the increase.

[0036] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof (or variant thereof) has an inhibitory effect on CD38 NADase activity. In such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof can be, or can be derived from, e.g., aCD38-a-323 or aCD38-a-306. The inhibitory effect on CD38 NADase activity can be measured, for example, by measuring the conversion of E-NAD+ to 5'-eAMP in Jurkat cells, as seen in the assay of the Examples. In some embodiments, the inhibitory effect on CD38 NADase activity is at least about 10% lower compared to CD38 NADase activity in the presence of an IgG non-binding control antibody as measured by the conversion of E-NAD+ to 5'-eAMP in Jurkat cells. In some embodiments, the inhibitory effect is at least about 10% lower compared to CD38 NADase activity in the presence of an IgG non-binding control antibody as measured by the conversion of E-NAD+ to 5'-eAMP in Jurkat cells. It may be at least about 15%, at least about 20%, or at least about 25% lower compared to NADase activity.

[0037] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof (or variant thereof) reduces CD38 NADase activity to about 25% or more of CD38 NADase activity in the presence of a non-IgG binding control antibody as measured by conversion of E-NAD+ to 5'-eAMP in Jurkat cells. Preferably, the antibody reduces CD38 NADase activity to about 30% or more, about 40% or more, or about 50% or more of CD38 NADase activity in the presence of a non-IgG binding control antibody. Preferably, the antibody reduces CD38 NADase activity to 25%-95%, about 30%-90%, or about 40%-90% of CD38 cyclase activity in the presence of a non-IgG binding control antibody. This means that in the presence of the anti-CD38 antibody or antigen-binding fragment thereof, CD38 NADase activity is still present in Jurkat cells, but in a reduced amount compared to CD38 NADase activity in the presence of a non-IgG binding control antibody.

[0038] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof (or variant thereof) has a stimulatory effect on CD38 cyclase activity. The CD38 antibody or antigen-binding fragment thereof may be, for example, aCD38-a-323 or may be derived therefrom. Stimulatory effect on CD38 cyclase activity may be measured, for example, by measuring the conversion of NGD+ to cGDPR in Jurkat cells, as seen in the assay of the examples. In some embodiments, the stimulatory effect on CD38 cyclase activity may be at least 10% higher compared to CD38 cyclase activity in the presence of a non-binding IgG control antibody, as measured by the conversion of NGD+ to cGDPR in Jurkat cells. In some embodiments, the stimulatory effect may be at least about 15%, at least about 20%, at least about 25% higher, at least about 50% higher, at least about 100% higher, at least about 200% higher, at least about 300% higher, at least about 400% higher compared to CD38 cyclase in the presence of a non-binding IgG control antibody. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof has a higher stimulatory effect on CD38 cyclase compared to daratumumab.

[0039] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof (or variant thereof) has an inhibitory effect on CD38 cyclase activity. In such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof can be, or can be derived from, for example, aCD38-b-348, aCD38-a-306, or aCD38-a-327. The inhibitory effect on CD38 cyclase activity can be measured, for example, by measuring the conversion of NGD+ to cGDPR in Jurkat cells, as seen in the assay of the Examples. The inhibitory effect on CD38 cyclase activity can result in at least 10% less CD38 activity compared to the CD38 cyclase activity in the presence of an IgG non-binding control antibody, as measured by the conversion of NGD+ to cGDPR in Jurkat cells. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof has an inhibitory effect on CD38 cyclase that is less than the inhibitory effect of daratumumab on CD38 cyclase activity under the same or substantially the same conditions. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof reduces CD38 cyclase activity to about 25% or more of CD38 cyclase activity in the presence of a non-IgG binding control antibody as measured by conversion of NGD+ to cGDPR in Jurkat cells. Preferably. The antibody reduces CD38 cyclase activity to about 30% or more, about 40% or more, or about 50% or more of CD38 cyclase activity in the presence of a non-IgG binding control antibody. Preferably, the antibody reduces CD38 cyclase activity to 25%-95%, about 30%-90%, or about 50%-90% of CD38 cyclase activity in the presence of a non-IgG binding control antibody. This means that in the presence of the anti-CD38 antibody or antigen-binding fragment thereof, CD38 cyclase activity is still present in Jurkat cells, but in a reduced amount compared to CD38 cyclase activity in the presence of a non-IgG binding control antibody. In such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof may be or be derived from, for example, aCD38-b-348, aCD38-a-306, or aCD38-a-327.

[0040] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof (or variant thereof) has an inhibitory effect on CD38 cyclase activity and an inhibitory effect on CD38 NADase activity. In such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof may be, or may be derived from, e.g., aCD38-a306. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof has a stimulatory effect on CD38 cyclase activity and an inhibitory effect on CD38 NADase activity, e.g., the antibody or antigen-binding fragment thereof may be, or may be derived from, e.g., aCD38-a-323.

[0041] Daratumumab has been shown to inhibit cyclase activity and stimulate NADase activity. In contrast, the antibodies of the present invention stimulate cyclase activity, have no effect on cyclase activity, or inhibit cyclase activity to a lesser extent than daratumumab (e.g., cyclase activity). cyclase activity is at least 2-fold higher in the presence of an antibody of the invention compared to the cyclase activity in the presence of daratumumab under the same or substantially the same conditions), and the antibody of the invention either has no effect on NADase activity or inhibits NADase activity.

[0042] In some embodiments, the CD38 modulating antibody agents provided are exemplified by antibodies having the sequence of aCD38-a-323, and more generally antibodies or agents that are or comprise one or more antigen-binding fragments or portions thereof, e.g., antibodies or agents that comprise the aCD38-a-323-HCDR3 amino acid sequence (SEQ ID NO:3) as variable heavy chain complementarity determining region 3, and / or in some embodiments comprise one or both of the aCD38-a-323 HCDR1 (SEQ ID NO:1) and HCDR2 (SEQ ID NO:2) sequences, and / or that compete with aCD38-a-323 for binding to the human CD38 extracellular domain.

[0043] In some embodiments, the CD38 modulating antibody agents provided are exemplified by antibodies having the sequence of aCD38-a-306, and more generally antibodies or agents that are or comprise one or more antigen-binding fragments or portions thereof, e.g., antibodies or agents that comprise the aCD38-a-306-HCDR3 amino acid sequence (SEQ ID NO: 11) as variable heavy chain complementarity determining region 3, and / or in some embodiments comprise one or both of the aCD38-a-306 HCDR1 (SEQ ID NO: 9) and HCDR2 (SEQ ID NO: 10) sequences, and / or that compete with aCD38-a-306 for binding to the human CD38 extracellular domain.

[0044] In some embodiments, the CD38 modulating antibody agents provided are exemplified by antibodies having the sequence of aCD38-b-329, and more generally antibodies or agents that are or comprise one or more antigen-binding fragments or portions thereof, e.g., antibodies or agents that comprise the aCD38-b-329-HCDR3 (SEQ ID NO: 19) amino acid sequence as variable heavy chain complementarity determining region 3, and / or in some embodiments comprise one or both of the aCD38-b-329 HCDR1 (SEQ ID NO: 17) and HCDR2 (SEQ ID NO: 18) sequences, and / or that compete with aCD38-b-329 for binding to the human CD38 extracellular domain.

[0045] In some embodiments, the CD38 modulating antibody agents provided are exemplified by antibodies having the sequence of aCD38-b-348, and more generally antibodies or agents that are or comprise one or more antigen-binding fragments or portions thereof, e.g., antibodies or agents that comprise the aCD38-b-348-HCDR3 amino acid sequence (SEQ ID NO:27) as variable heavy chain complementarity determining region 3, and / or in some embodiments comprise one or both of the aCD38-b-348 HCDR1 (SEQ ID NO:25) and HCDR2 (SEQ ID NO:26) sequences, and / or that compete with aCD38-b-348 for binding to the human CD38 extracellular domain.

[0046] In some embodiments, the CD38 modulating antibody agents provided are exemplified by antibodies having the sequence of aCD38-a-327, and more generally antibodies or agents that are or comprise one or more antigen-binding fragments or portions thereof, e.g., antibodies or agents that comprise the aCD38-a-327-HCDR3 amino acid sequence (SEQ ID NO: 35) as variable heavy chain complementarity determining region 3, and / or in some embodiments comprise one or both of the aCD38-a-327 HCDR1 (SEQ ID NO: 33) and HCDR2 (SEQ ID NO: 34) sequences, and / or that compete with aCD38-a-327 for binding to the human CD38 extracellular domain.

[0047] In some embodiments, the provided antibody or antigen-binding fragment thereof is -8 M range or less (e.g., 10 -9 M range, 10 -10 M range, 10 -11 In some embodiments, the Kd is in the range of 10 -11 M~10 -8 Kd for assessing the binding affinity of an antibody or antigen-binding fragment thereof can be obtained by standard methodologies including surface plasmon resonance (SPR), for example, Biacore analysis or analysis using Forte Bio Octet Systems.

[0048] In some embodiments, CD38 modulating antibody agents (e.g., antibodies or antigen-binding fragments thereof) are provided that bind to an epitope on human CD38 bound by aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348. In some embodiments, such provided CD38 modulating antibody agents may bind to human CD38 extracellular domain. In some embodiments, provided CD38 modulating antibody agents may bind to an epitope of CD38 (e.g., as assessed using one or more assays described herein or otherwise known in the art). In some embodiments, provided antibodies or antigen-binding fragments thereof bind to human and cynomolgus CD38 (e.g., extracellular epitopes on human and cynomolgus CD38) at 10 -8 M range or less (e.g., 10 -9 M range or less).

[0049] In some embodiments, the provided antibody or antigen-binding fragment thereof binds to a mutant human CD38 (compared to non-mutated human CD38 (SEQ ID NO:47)), in which the serine residue at position 274 has been substituted with a phenylalanine. In such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof can be or be derived from, for example, aCD38-a-327, aCD38-b-329, aCD38-b-348, or aCD38-a-323.

[0050] In some embodiments, the provided antibodies or antigen-binding fragments thereof bind to mutant human CD38 (compared to non-mutated human CD38 (SEQ ID NO:47)), in which the aspartic acid residue at position 202 has been replaced with a glycine residue. In such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof can be or be derived from, for example, aCD38-a-327, aCD38-b-329, aCD38-b-348, aCD38-a-323, or aCD38-a-306.

[0051] In some embodiments, the provided antibody or antigen-binding fragment thereof binds to a mutant human CD38 (compared to non-mutated human CD38 (SEQ ID NO:47)) in which the serine residue at position 274 is replaced with a phenylalanine and the aspartic acid residue at position 202 is replaced with a glycine residue. In such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof can be or be derived from, for example, aCD38-a-327, aCD38-b-329, aCD38-b-348, or aCD38-a-323.

[0052] In some embodiments, the provided antibody or antigen-binding fragment thereof does not bind or binds with reduced affinity (compared to non-mutated human CD38 (SEQ ID NO:47)) to a mutant human CD38 in which the serine residue at position 274 has been replaced with a phenylalanine and in which the aspartic acid residue at position 202 has been replaced with a glycine residue. In such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof can be, or can be derived from, e.g., aCD38-a-306.

[0053] Among other things, the present disclosure provides procedures (FIG. 1) that may be utilized to identify and / or characterize particularly useful CD38 modulating antibody agents (e.g., anti-CD38 antibodies or antigen-binding fragments thereof) described herein (e.g., anti-CD38 antibodies or antigen-binding fragments thereof characterized by certain structural and / or functional features, such as specific binding to human CD38 (e.g., an extracellular epitope thereof), inclusion of one or more CDR sequence elements described herein (particularly inclusion of HCDR3 sequence elements, optionally in combination with HCDR1 and / or HCDR2 elements), cell activation activity described herein, cytotoxic activity (e.g., against immune regulatory cells with relatively high CD38 levels on their surface), and combinations thereof). In some embodiments, particularly useful anti-CD38 antibodies described herein are characterized by more than one such feature. In some embodiments, one or more antibodies described herein may be characterized as a CD38 modulating antibody agent.

[0054] Thus, as exemplified herein, aCD38-a-323 sequence (specifically, aCD38-a-323-HCDR3 (SEQ ID NO: 3) and / or aCD38-a-323-LCDR3 (SEQ ID NO: 7)), CD38-a-306 sequence (specifically, aCD38-a-306-HCDR3 (SEQ ID NO: 11) and / or aCD38-a-306-LCDR3 (SEQ ID NO: 15)), aCD38-b-329 sequence (specifically, aCD38-b-329-HCDR3 (SEQ ID NO: 19) and / or aCD38-b-329-LCDR3 (SEQ ID NO: 23)), aCD38-a-327 sequence (specifically, aCD38-a-327-HCDR3 (SEQ ID NO: 35) and / or aCD38-a-327-LCDR3 (SEQ ID NO: 39), or a Certain antibodies and / or antigen-binding fragments comprising the CD38-b-348 sequence (specifically aCD38-b-348-HCDR3 (SEQ ID NO:27) and / or aCD38-b-348-LCDR3 (SEQ ID NO:31)) are characterized by such desirable structural and / or functional characteristics, and such antibodies and / or antigen-binding fragments thereof (and variants thereof) may be referred to herein as CD38-modulating antibody agents. In addition, according to the present disclosure, antibodies and antigen-binding fragments thereof that compete with aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348 may be particularly useful antibodies, and such antibodies and / or antigen-binding fragments thereof may also be referred to herein as CD38-modulating antibody agents.

[0055] The antibodies (and / or antigen-binding fragments thereof) described herein may be particularly useful in medicine (e.g., therapy and / or prophylaxis, e.g., treatment of cancer) and / or for use in methods that require or include targeting epitopes within the human CD38 extracellular domain, such as those identified as aCD38-b-ep for aCD38-b-348 and aCD38-b-329, or aCD38ep-a and aCD38ep-b for CD38-a-327, within the human CD38 extracellular domain. The antibodies or antigen-binding fragments thereof provided may be prepared to present the most appropriate isotype, in particular a human isotype from the group consisting of IgG1, IgG2, IgG3, and IgG4 isotype antibodies, more particularly human IgG1.

[0056] In one aspect, the present invention provides aCD38-a-323-HCDR3 amino acid sequence and polypeptides comprising same, such as antibodies or antigen-binding fragments comprising the aCD38-a-323-HCDR3 amino acid sequence (SEQ ID NO:3) as variable heavy chain complementarity determining region 3. In some embodiments, such antibodies or antigen-binding fragments are a) the aCD38-a-323-HCDR1 amino acid sequence (SEQ ID NO: 1) as variable heavy chain complementarity determining region 1, and / or b) It may be further characterized by comprising additional aCD38-a-323 amino acid sequence elements, such as the aCD38-a-323-HCDR2 amino acid sequence (SEQ ID NO: 2) as variable heavy chain complementarity determining region 2.

[0057] In some embodiments, the provided antibodies or antigen-binding fragments thereof may further comprise the above-defined variable heavy chain complementarity determining regions (i.e., aCD38-a-323 amino acid sequence elements) specifically separated by antibody framework sequences, such as those contained in the aCD38-a-323-HCDR123 amino acid sequence (SEQ ID NO: 4), in the correct order, in particular to correctly exert their binding and functional properties. For example, in some embodiments, the provided antibodies or antigen-binding fragments thereof may comprise the aCD38-a-323-HCDR123 amino acid sequence (SEQ ID NO: 4, or HCDR1, HCDR2, and HCDR3 sequences thereof), and optionally a) the aCD38-a-323-LCDR1 amino acid sequence (SEQ ID NO:5) as variable light chain complementarity determining region 1; b) the aCD38-a-323-LCDR2 amino acid sequence (SEQ ID NO: 6) as variable light chain complementarity determining region 2, and c) It may comprise the aCD38-a-323-LCDR3 amino acid sequence (SEQ ID NO: 7) as variable light chain complementarity determining region 3.

[0058] Thus, in some embodiments, the invention provides an isolated antibody or antigen-binding fragment thereof comprising a variable heavy chain comprising the aCD38-a-323-HCDR123 amino acid sequence (SEQ ID NO: 4). Preferably, such an isolated antibody or antigen-binding fragment thereof further comprises a variable light chain comprising the aCD38-a-323-LCDR123 amino acid sequence (SEQ ID NO: 8), as described in the Examples.

[0059] In some embodiments, the present invention provides a method for the preparation of a nucleic acid having the sequence: JPEG2025028972000002.jpg17170, and / or a variable heavy chain comprising the sequence: The present invention provides an isolated antibody or antigen-binding fragment thereof comprising a variable light chain comprising JPEG2025028972000003.jpg15170.

[0060] In some embodiments, the variable heavy chain sequence of aCD38-a-323 has the sequence: JPEG2025028972000004.jpg22170, and the variable light chain sequence of aCD38-a-323 has the sequence: Contains JPEG2025028972000005.jpg15170.

[0061] The present invention also provides an antibody or antigen-binding fragment thereof comprising the sequence of aCD38-a-323-HCDR3 as HCDR3 and the sequence of aCD38-a-323-LCDR3 as LCDR3.

[0062] The present invention also relates to variant antibodies and antigen-binding fragments thereof having a certain percent identity to a reference sequence, such as the CDR sequence or heavy or light chain variable sequence of aCD38-a-323. Such antibodies and antigen-binding fragments thereof may also be referred to herein as CD38 modulating antibody agents.

[0063] For example, in some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 48. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 48. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 48. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising the amino acid sequence of SEQ ID NO: 48.

[0064] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 49. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 49. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 49. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising the amino acid sequence of SEQ ID NO: 49.

[0065] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 48 and a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 49. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 48 and a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 49. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 48 and a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 49. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising the amino acid sequence of SEQ ID NO: 48 and a variable light chain sequence comprising the amino acid sequence of SEQ ID NO: 49.

[0066] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 72. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 72. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 72. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising the amino acid sequence of SEQ ID NO: 72.

[0067] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 73. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 73. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 73. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 73. Contains the strand sequence.

[0068] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 72 and a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 73. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 72 and a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 73. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 72 and a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 73. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 72 and a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 73.

[0069] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 4. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 4. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 4. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising the amino acid sequence of SEQ ID NO: 4.

[0070] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 8. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 8. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 8. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising the amino acid sequence of SEQ ID NO: 8.

[0071] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO:4 and a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO:8. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO:4 and a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO:8. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:4 and a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:8. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence of SEQ ID NO:4 and a variable light chain sequence comprising an amino acid sequence of SEQ ID NO:8.

[0072] Such variant antibodies and antigen-binding fragments thereof may retain or exhibit the same (or substantially the same) functional and pharmacological properties as described for antibodies and antigen-binding fragments thereof having the heavy and light chain variable sequences disclosed herein for aCD38-a-323.

[0073] Furthermore, aCD38-a-323 amino acid sequence also refers to an antibody sequence defined by the number of substitutions to the aCD38-a-323 amino acid sequence elements defined above. For example, such a sequence may include, as the variable heavy chain complementarity determining region 3 (HCDR3), a sequence that contains up to 1, 2, 3, or 4 amino acid substitutions within aCD38-a-323-HCDR3. In a further embodiment, the aCD38-a-323 amino acid sequence also refers to an antibody sequence comprising, as variable heavy chain complementarity determining regions 1, 2, and 3 (HCDR1, HCDR2, and HCDR3), aCD38-a-323-HCDR1, aCD38-a-323-HCDR2, and aCD38-a-323-HCDR3, a sequence comprising up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions, more preferably a CD38-a-323-HCDR123 (SEQ ID NO: 4) or in SEQ ID NO: 48 or SEQ ID NO: 72. In some embodiments, aCD38-a-323 amino acid sequence also refers to an antibody sequence that comprises, as a variable heavy chain sequence, a sequence that comprises up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions within the framework regions of the variable heavy chain sequence. Antibodies that display such aCD38-a-323 amino acid sequence elements and such substitutions may still display the binding and / or functional properties of aCD38-a-323, generally a CD38 modulating antibody agent.

[0074] Such aCD38-a-323 amino acid sequence may also include, as variable light chain complementarity determining region 3 (LCDR3), a sequence that includes up to 1, 2, 3, or 4 amino acid substitutions within aCD38-a-323-LCDR3. In a further embodiment, the aCD38-a-323 amino acid sequence also refers to an antibody sequence comprising, as variable light chain complementarity determining regions 1, 2, and 3 (LCDR1, LCDR2, and LCDR3), aCD38-a-323-LCDR1, aCD38-a-323-LCDR2, and aCD38-a-323-LCDR3, a sequence comprising up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions, more preferably aCD38-a-323-LCDR123 (SEQ ID NO: 8) or SEQ ID NO: 49 or SEQ ID NO: 73. In some embodiments, aCD38-a-323 amino acid sequence also refers to an antibody sequence that comprises, as a variable light chain sequence, a sequence that comprises up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions within the framework regions of the variable light chain sequence. Antibodies that display such aCD38-a-323 amino acid sequence elements and such substitutions may still display the binding and / or functional properties of aCD38-a-323, generally a CD38 modulating antibody agent.

[0075] Thus, in one embodiment, the invention provides an anti-CD38 antibody agent (i.e., an antibody or antigen-binding fragment thereof, and variants thereof as described herein, e.g., variants mutated to remove the DG motif) comprising: a. the variable heavy chain region sequence of aCD38-a-323 (or a variant thereof, e.g. an affinity matured variant thereof), or a variable heavy chain region sequence having up to five amino acid substitutions compared to the variable heavy chain region sequence of aCD38-a-323 (or a variant thereof, e.g. an affinity matured variant thereof), and / or b. The variable light chain region sequence of aCD38-a-323 (or a variant thereof, e.g., an affinity matured variant thereof), or a variable light chain region sequence having up to five amino acid substitutions compared to the variable light chain region sequence of aCD38-a-323 (or a variant thereof, e.g., an affinity matured variant thereof).

[0076] The aCD38-a-323 heavy chains that may incorporate amino acid substitutions include SEQ ID NOs: 4, 48, and 72. The aCD38-a-323 light chains that may incorporate amino acid substitutions include SEQ ID NOs: 8, 49, and 73.

[0077] The amino acid substitutions preferably do not adversely affect or are not capable of affecting the functional properties of the antibody. It does not affect quality adversely. Therefore, these substitutions can be considered as conservative amino acid substitutions. Preferably, when amino acid substitutions occur, they occur in a 1:1 ratio so that the total length of the heavy and / or light chain variable region does not change.

[0078] In one aspect, the present invention provides aCD38-a-306-HCDR3 amino acid sequence and polypeptides comprising same, such as antibodies or antigen-binding fragments comprising the aCD38-a-306-HCDR3 amino acid sequence (SEQ ID NO: 11) as variable heavy chain complementarity determining region 3. In some embodiments, such antibodies or antigen-binding fragments are a) the aCD38-a-306-HCDR1 amino acid sequence (SEQ ID NO: 9) as variable heavy chain complementarity determining region 1, and / or b) It may be further characterized by comprising additional aCD38-a-306 amino acid sequence elements, such as the aCD38-a-306-HCDR2 amino acid sequence (SEQ ID NO: 10), as variable heavy chain complementarity determining region 2.

[0079] In some embodiments, the provided antibodies or antigen-binding fragments thereof may further comprise the above-defined variable heavy chain complementarity determining regions (i.e., the aCD38-a-306 amino acid sequence elements) specifically separated by an antibody framework sequence, such as that contained in the aCD38-a-306-HCDR123 amino acid sequence (SEQ ID NO: 12), in the correct order, in particular to correctly exert their binding and functional properties. For example, in some embodiments, the provided antibodies or antigen-binding fragments thereof may comprise the aCD38-a-306-HCDR123 amino acid sequence (SEQ ID NO: 12, or the HCDR1, HCDR2, and HCDR3 sequences thereof), and optionally a) the aCD38-a-306-LCDR1 amino acid sequence (SEQ ID NO: 13) as variable light chain complementarity determining region 1; b) the aCD38-a-306-LCDR2 amino acid sequence (SEQ ID NO: 14) as variable light chain complementarity determining region 2, and c) It may comprise the aCD38-a-306-LCDR3 amino acid sequence (SEQ ID NO: 15) as variable light chain complementarity determining region 3.

[0080] Thus, in some embodiments, the invention provides an isolated antibody or antigen-binding fragment thereof comprising a variable heavy chain comprising the aCD38-a-306-HCDR123 amino acid sequence (SEQ ID NO: 12). Preferably, such an isolated antibody or antigen-binding fragment thereof further comprises a variable light chain comprising the aCD38-a-306-LCDR123 amino acid sequence (SEQ ID NO: 16), as described in the Examples.

[0081] In some embodiments, the present invention provides a method for the preparation of a nucleic acid having the sequence: JPEG2025028972000006.jpg16170, and / or a variable heavy chain comprising the sequence: The present invention provides an isolated antibody or antigen-binding fragment thereof comprising a variable light chain comprising JPEG2025028972000007.jpg15170.

[0082] In some embodiments, the variable heavy chain sequence of aCD38-a-306 has the sequence: JPEG2025028972000008.jpg16170, and the variable light chain sequence of aCD38-a-306 has the sequence: Contains JPEG2025028972000009.jpg16170.

[0083] The present invention also provides an antibody or antigen-binding fragment thereof comprising the sequence of aCD38-a-306-HCDR3 as HCDR3 and the sequence of aCD38-a-306-LCDR3 as LCDR3.

[0084] The present invention also provides variant antibodies and antigen-binding fragments thereof having a certain percent identity to a reference sequence, such as the CDR sequence or heavy or light chain variable sequence of aCD38-a-306. Such antibodies and antigen-binding fragments thereof may also be referred to herein as CD38 modulating antibody agents.

[0085] For example, in some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 50. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 50. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 50. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising the amino acid sequence of SEQ ID NO: 50.

[0086] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 51. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 51. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 51. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising the amino acid sequence of SEQ ID NO: 51.

[0087] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO:50 and a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO:51. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO:50 and a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO:51. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:50 and a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:51. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:50 and a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:51.

[0088] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 74. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 74. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 74. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising the amino acid sequence of SEQ ID NO: 74.

[0089] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 75. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 75. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 75. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising the amino acid sequence of SEQ ID NO: 75.

[0090] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 74 and a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 75. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 74 and a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 75. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 74 and a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 75. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence of SEQ ID NO: 74 and a variable light chain sequence comprising an amino acid sequence of SEQ ID NO: 75.

[0091] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 12. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 12. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 12. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising the amino acid sequence of SEQ ID NO: 12.

[0092] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 16. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 16. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 16. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising the amino acid sequence of SEQ ID NO: 16.

[0093] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 12 and a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 16. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 12 and a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 16. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 12 and a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 16. ... the amino acid sequence of SEQ ID NO: 12 and a variable light chain sequence comprising the amino acid sequence of SEQ ID NO: 16.

[0094] Such variant antibodies and antigen-binding fragments thereof may retain or exhibit the same (or substantially the same) functional and pharmacological properties as described for antibodies and antigen-binding fragments thereof having the heavy and light chain variable sequences disclosed herein for aCD38-a-306.

[0095] Furthermore, aCD38-a-306 amino acid sequence also refers to an antibody sequence defined by the number of substitutions for the aCD38-a-306 amino acid sequence elements defined above. For example, such a sequence may include, as the variable heavy chain complementarity determining region 3 (HCDR3), a sequence that contains up to 1, 2, 3, or 4 amino acid substitutions within aCD38-a-306-HCDR3. In a further embodiment, the aCD38-a-306 amino acid sequence also refers to an antibody sequence comprising, as variable heavy chain complementarity determining regions 1, 2, and 3 (HCDR1, HCDR2, and HCDR3), aCD38-a-306-HCDR1, aCD38-a-306-HCDR2, and aCD38-a-306-HCDR3, a sequence comprising up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions, more preferably within aCD38-a-306-HCDR123 (SEQ ID NO: 12) or within SEQ ID NO: 50 or SEQ ID NO: 74. In some embodiments, the aCD38-a-306 amino acid sequence also refers to an antibody sequence that comprises, as a variable heavy chain sequence, a sequence that comprises up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions within the framework regions of the variable heavy chain sequence. Antibodies that display such aCD38-a-306 amino acid sequence elements and such substitutions may still display the binding and / or functional properties of aCD38-a-306, generally a CD38 modulating antibody agent.

[0096] Such aCD38-a-306 amino acid sequence may also include, as variable light chain complementarity determining region 3 (LCDR3), a sequence that includes up to 1, 2, 3, or 4 amino acid substitutions within aCD38-a-306-LCDR3. In a further embodiment, the aCD38-a-306 amino acid sequence also refers to an antibody sequence comprising, as variable light chain complementarity determining regions 1, 2, and 3 (LCDR1, LCDR2, and LCDR3), aCD38-a-306-LCDR1, aCD38-a-306-LCDR2, and aCD38-a-306-LCDR3, a sequence comprising up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions, more preferably a CD38-a-306-LCDR123 (SEQ ID NO: 16) or within SEQ ID NO: 51 or SEQ ID NO: 75. In some embodiments, the aCD38-a-306 amino acid sequence also refers to an antibody sequence that comprises, as a variable light chain sequence, a sequence that comprises up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions within the framework regions of the variable light chain sequence. Antibodies that display such aCD38-a-306 amino acid sequence elements and such substitutions may still display the binding and / or functional properties of aCD38-a-306, generally a CD38 modulating antibody agent.

[0097] Thus, in one embodiment, the invention provides an anti-CD38 antibody agent (i.e., an antibody or antigen-binding fragment thereof, and variants thereof as described herein, e.g., variants mutated to remove the DG motif) comprising: a. aCD38-a-306 (or a variant thereof, e.g., its affinity maturation barrier aCD38-a-306 (or a variant thereof, e.g., an affinity matured variant thereof), or a variable heavy chain region sequence having up to five amino acid substitutions compared to the variable heavy chain region sequence of aCD38-a-306 (or a variant thereof, e.g., an affinity matured variant thereof), and / or b. The variable light chain region sequence of aCD38-a-306 (or a variant thereof, e.g., an affinity matured variant thereof), or a variable light chain region sequence having up to five amino acid substitutions compared to the variable light chain region sequence of aCD38-a-306 (or a variant thereof, e.g., an affinity matured variant thereof).

[0098] The aCD38-a-306 heavy chains that may incorporate amino acid substitutions include SEQ ID NOs: 12, 50, and 74. The aCD38-a-306 light chains that may incorporate amino acid substitutions include SEQ ID NOs: 16, 51, and 75.

[0099] Amino acid substitutions preferably do not adversely affect or do not substantially adversely affect the functional properties of the antibody.Therefore, these substitutions can be considered as conservative amino acid substitutions.Preferably, when amino acid substitutions occur, they occur in a 1:1 ratio so that the total length of the heavy and / or light chain variable regions does not change.

[0100] In one aspect, the invention provides aCD38-b-329-HCDR3 amino acid sequence and polypeptides comprising same, such as antibodies or antigen-binding fragments comprising the aCD38-b-329-HCDR3 amino acid sequence (SEQ ID NO: 19) as variable heavy chain complementarity determining region 3. In some embodiments, such antibodies or antigen-binding fragments comprise: a) the aCD38-b-329-HCDR1 amino acid sequence (SEQ ID NO: 17) as variable heavy chain complementarity determining region 1, and / or b) It may be further characterized by comprising additional aCD38-b-329 amino acid sequence elements, such as the aCD38-b-329-HCDR2 amino acid sequence (SEQ ID NO: 18) as variable heavy chain complementarity determining region 2.

[0101] In some embodiments, the provided antibodies or antigen-binding fragments thereof may further comprise the above-defined variable heavy chain complementarity determining regions (i.e., the aCD38-b-329 amino acid sequence elements) specifically separated by an antibody framework sequence, such as that contained in the aCD38-b-329-HCDR123 amino acid sequence (SEQ ID NO:20), in the correct order, in particular for correctly exerting their binding and functional properties. For example, in some embodiments, the provided antibodies or antigen-binding fragments thereof may comprise the aCD38-b-329-HCDR123 amino acid sequence (SEQ ID NO:20, or the HCDR1, HCDR2, and HCDR3 sequences thereof), and optionally a) the aCD38-b-329-LCDR1 amino acid sequence (SEQ ID NO: 21) as variable light chain complementarity determining region 1; b) the aCD38-b-329-LCDR2 amino acid sequence (SEQ ID NO: 22) as variable light chain complementarity determining region 2, and c) It may comprise the aCD38-b-329-LCDR3 amino acid sequence (SEQ ID NO: 23) as variable light chain complementarity determining region 3.

[0102] Thus, in some embodiments, the invention provides an isolated antibody or antigen-binding fragment thereof comprising a variable heavy chain comprising the aCD38-b-329-HCDR123 amino acid sequence (SEQ ID NO: 20). Preferably, such an isolated antibody or antigen-binding fragment thereof further comprises a variable light chain comprising the aCD38-b-329-LCDR123 amino acid sequence (SEQ ID NO: 24), as described in the Examples.

[0103] In some embodiments, the variable heavy chain sequence of aCD38-b-329 has the sequence: JPEG2025028972000010.jpg21170, and the variable light chain sequence of aCD38-b-329 has the sequence: Contains JPEG2025028972000011.jpg16170.

[0104] The present invention also provides an antibody or antigen-binding fragment thereof comprising an HCDR3 having the sequence aCD38-b-329-HCDR3 and an LCDR3 having a sequence selected from the group consisting of aCD38-b-329-LCDR3, aCD38-b-329-m6-LCDR3, and aCD38-b-329-m7-LCDR3.

[0105] The present invention also provides an antibody or antigen-binding fragment thereof comprising the sequence aCD38-b-329-HCDR1 as HCDR1, the sequence aCD38-b-329-HCDR2 as HCDR2, the sequence aCD38-b-329-HCDR3 as HCDR3, the sequence aCD38-b-329-LCDR1 as LCDR1, and the sequence aCD38-b-329-LCDR2 as LCDR2, and comprising an LCDR3 having a sequence selected from the group consisting of aCD38-b-329-LCDR3, aCD38-b-329-m6-LCDR3, and aCD38-b-329-m7-LCDR3.

[0106] The present invention also provides an antibody or antigen-binding fragment thereof comprising the sequence of aCD38-b-329-HCDR123 as a variable heavy chain region, and a variable light chain region having a sequence selected from the group consisting of aCD38-b-329-LCDR123, aCD38-b-329-m6-LCDR123, and aCD38-b-329-m7-LCDR123.

[0107] The present invention also provides an antibody or antigen-binding fragment thereof comprising the sequence of aCD38-b-329-VH as a variable heavy chain region and a variable light chain region having a sequence selected from the group consisting of aCD38-b-329-VL, aCD38-b-329-m6-VL, and aCD38-b-329-m7-VL.

[0108] The present invention also provides variant antibodies and antigen-binding fragments thereof having a certain percent identity to a reference sequence, such as the CDR sequence or heavy or light chain variable sequence of aCD38-b-329. Such antibodies and antigen-binding fragments thereof may also be referred to herein as CD38 modulating antibody agents.

[0109] For example, in some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 52. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 52. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 52. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising the amino acid sequence of SEQ ID NO: 52.

[0110] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof has the sequence identical to SEQ ID NO:53. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO:53. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:53. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising the amino acid sequence of SEQ ID NO:53.

[0111] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO:52 and a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO:53. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO:52 and a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO:53. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:52 and a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:53. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:52 and a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:53.

[0112] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 20. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 20. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 20. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising the amino acid sequence of SEQ ID NO: 20.

[0113] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 24. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 24. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 24. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising the amino acid sequence of SEQ ID NO: 24.

[0114] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO:20 and a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO:24. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO:20 and a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO:24. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:20 and a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:24. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:20 and a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:24. .

[0115] Such variant antibodies and antigen-binding fragments thereof may retain or exhibit the same (or substantially the same) functional and pharmacological properties as described for antibodies and antigen-binding fragments thereof having the heavy and light chain variable sequences disclosed herein for aCD38-b-329.

[0116] Furthermore, aCD38-b-329 amino acid sequence also refers to an antibody sequence defined by the number of substitutions to the aCD38-b-329 amino acid sequence elements defined above. For example, such a sequence may include, as the variable heavy chain complementarity determining region 3 (HCDR3), a sequence that contains up to 1, 2, 3, or 4 amino acid substitutions within aCD38-b-329-HCDR3. In a further embodiment, the aCD38-b-329 amino acid sequence also refers to an antibody sequence comprising, as variable heavy chain complementarity determining regions 1, 2, and 3 (HCDR1, HCDR2, and HCDR3), aCD38-b-329-HCDR1, aCD38-b-329-HCDR2, and aCD38-b-329-HCDR3, a sequence comprising up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions, more preferably a sequence comprising up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions, within aCD38-b-329-HCDR123 (SEQ ID NO: 20) or within SEQ ID NO: 52. In some embodiments, aCD38-b-329 amino acid sequence also refers to an antibody sequence that comprises, as a variable heavy chain sequence, a sequence that comprises up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions within the framework regions of the variable heavy chain sequence. Antibodies that display such aCD38-b-329 amino acid sequence elements and such substitutions may still display the binding and / or functional properties of aCD38-b-329, generally a CD38 modulating antibody agent.

[0117] Such aCD38-b-329 amino acid sequence may also include as a variable light chain complementarity determining region 3 (LCDR3) a sequence that includes up to 1, 2, 3, or 4 amino acid substitutions within aCD38-b-329-LCDR3. In a further embodiment, the aCD38-b-329 amino acid sequence also refers to an antibody sequence that comprises, as variable light chain complementarity determining regions 1, 2, and 3 (LCDR1, LCDR2, and LCDR3), a sequence that contains up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions in aCD38-b-329-LCDR1, aCD38-b-329-LCDR2, and aCD38-b-329-LCDR3, more preferably a sequence that contains up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions in aCD38-b-329-LCDR123 (SEQ ID NO: 24) or in SEQ ID NO: 53. In some embodiments, the aCD38-b-329 amino acid sequence also refers to an antibody sequence that comprises, as a variable light chain sequence, a sequence that comprises up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions within the framework regions of the variable light chain sequence. Antibodies that display such aCD38-b-329 amino acid sequence elements and such substitutions may still display the binding and / or functional properties of aCD38-b-329, generally a CD38 modulating antibody agent.

[0118] Thus, in one embodiment, the invention provides an anti-CD38 antibody agent (i.e., an antibody or antigen-binding fragment thereof, and variants thereof as described herein, e.g., variants mutated to remove the DG motif) comprising: a. the variable heavy chain region sequence of aCD38-b-329 (or a variant thereof, e.g. an affinity matured variant thereof), or a variable heavy chain region sequence having up to five amino acid substitutions compared to the variable heavy chain region sequence of aCD38-b-329 (or a variant thereof, e.g. an affinity matured variant thereof), and / or b. the variable light chain region sequence of aCD38-b-329 (or a variant thereof, e.g., an affinity matured variant thereof), or a sequence that has up to five amino acid substitutions compared to the variable light chain region sequence of aCD38-b-329 (or a variant thereof, e.g., an affinity matured variant thereof); A variable light chain region sequence having the following substitutions:

[0119] aCD38-b-329 heavy chains that may incorporate amino acid substitutions include SEQ ID NOs: 20 and 52. aCD38-b-329 light chains that may incorporate amino acid substitutions include SEQ ID NOs: 24, 53, 62, 63, 68, and 69.

[0120] Amino acid substitutions preferably do not adversely affect or do not substantially adversely affect the functional properties of the antibody.Therefore, these substitutions can be considered as conservative amino acid substitutions.Preferably, when amino acid substitutions occur, they occur in a 1:1 ratio so that the total length of the heavy and / or light chain variable regions does not change.

[0121] In one aspect, the invention provides aCD38-b-348-HCDR3 amino acid sequence and polypeptides comprising same, such as antibodies or antigen-binding fragments comprising the aCD38-b-348-HCDR3 amino acid sequence (SEQ ID NO:27) as variable heavy chain complementarity determining region 3. In some embodiments, such antibodies or antigen-binding fragments comprise: a) the aCD38-b-348-HCDR1 amino acid sequence (SEQ ID NO: 25) as variable heavy chain complementarity determining region 1, and / or b) It may be further characterized by comprising additional aCD38-b-348 amino acid sequence elements, such as the aCD38-b-348-HCDR2 amino acid sequence (SEQ ID NO: 26) as variable heavy chain complementarity determining region 2.

[0122] In some embodiments, the provided antibodies or antigen-binding fragments thereof may further comprise the above-defined variable heavy chain complementarity determining regions (i.e., the aCD38-b-348 amino acid sequence elements) specifically separated by an antibody framework sequence, such as that contained in the aCD38-b-348-HCDR123 amino acid sequence (SEQ ID NO:28), in the correct order, in particular for correctly exerting their binding and functional properties. For example, in some embodiments, the provided antibodies or antigen-binding fragments thereof may comprise the aCD38-b-348-HCDR123 amino acid sequence (SEQ ID NO:28, or the HCDR1, HCDR2, and HCDR3 sequences thereof), and optionally a) the aCD38-b-348-LCDR1 amino acid sequence (SEQ ID NO: 29) as variable light chain complementarity determining region 1; b) the aCD38-b-348-LCDR2 amino acid sequence (SEQ ID NO: 30) as variable light chain complementarity determining region 2, and c) It may comprise the aCD38-b-348-LCDR3 amino acid sequence (SEQ ID NO: 31) as variable light chain complementarity determining region 3.

[0123] Thus, in some embodiments, the invention provides an isolated antibody or antigen-binding fragment thereof comprising a variable heavy chain comprising the aCD38-b-348-HCDR123 amino acid sequence (SEQ ID NO: 28). Preferably, such an isolated antibody or antigen-binding fragment thereof further comprises a variable light chain comprising the aCD38-b-348-LCDR123 amino acid sequence (SEQ ID NO: 32), as described in the Examples.

[0124] In some embodiments, the variable heavy chain sequence of aCD38-b-348 has the sequence: JPEG2025028972000012.jpg23170, and the variable light chain sequence of aCD38-a-348 has the sequence: Contains JPEG2025028972000013.jpg17170.

[0125] The present invention also provides an antibody or antigen-binding fragment thereof comprising an HCDR3 with the sequence aCD38-b-348-HCDR3 and an LCDR3 having a sequence selected from the group consisting of aCD38-b-348-LCDR3, aCD38-b-348-m1-LCDR3, aCD38-b-348-m2-LCDR3, aCD38-b-348-m3-LCDR3, and aCD38-b-348-m4-LCDR3.

[0126] The present invention also provides an antibody or antigen-binding fragment thereof comprising the sequence aCD38-b-348-HCDR1 as HCDR1, the sequence aCD38-b-348-HCDR2 as HCDR2, the sequence aCD38-b-348-HCDR3 as HCDR3, the sequence aCD38-b-348-LCDR1 as LCDR1, and the sequence aCD38-b-348-LCDR2 as LCDR2, and comprising an LCDR3 having a sequence selected from the group consisting of aCD38-b-348-LCDR3, aCD38-b-348-m1-LCDR3, aCD38-b-348-m2-LCDR3, aCD38-b-348-m3-LCDR3, and aCD38-b-348-m4-LCDR3.

[0127] The present invention also provides an antibody or antigen-binding fragment thereof comprising the sequence of aCD38-b-348-HCDR123 as a variable heavy chain region and a variable light chain region having a sequence selected from the group consisting of aCD38-b-348-LCDR123, aCD38-b-348-m1-LCDR123, aCD38-b-348-m2-LCDR123, aCD38-b-348-m3-LCDR123, and aCD38-b-348-m4-LCDR123.

[0128] The present invention also provides an antibody or antigen-binding fragment thereof comprising the sequence of aCD38-b-348-VH as a variable heavy chain region and a variable light chain region having a sequence selected from the group consisting of aCD38-b-348-VL, aCD38-b-348-m1-VL, aCD38-b-348-m2-VL, aCD38-b-348-m3-VL, and aCD38-b-348-m4-VL.

[0129] The present invention also provides variant antibodies and antigen-binding fragments thereof having a certain percent identity to a reference sequence, such as the CDR sequence or heavy or light chain variable sequence of aCD38-b-348. Such antibodies and antigen-binding fragments thereof may also be referred to herein as CD38 modulating antibody agents.

[0130] For example, in some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 54. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 54. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 54. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising the amino acid sequence of SEQ ID NO: 54.

[0131] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 55. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 55. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 55. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising the amino acid sequence of SEQ ID NO: 55.

[0132] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO:54 and a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO:55. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO:54 and a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO:55. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:54 and a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:55. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:54 and a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:55.

[0133] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 28. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 28. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 28. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising the amino acid sequence of SEQ ID NO: 28.

[0134] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 32. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 32. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 32. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising the amino acid sequence of SEQ ID NO: 32.

[0135] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO:28 and a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO:32. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO:28 and a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO:32. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:28 and a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:32. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence of SEQ ID NO:28 and a variable light chain sequence comprising an amino acid sequence of SEQ ID NO:32.

[0136] Such variant antibodies and antigen-binding fragments thereof may retain or exhibit the same (or substantially the same) functional and pharmacological properties as described for antibodies and antigen-binding fragments thereof having the heavy and light chain variable sequences disclosed herein for aCD38-b-348.

[0137] Furthermore, aCD38-b-348 amino acid sequence also refers to an antibody sequence defined by the number of substitutions to the aCD38-b-348 amino acid sequence elements defined above. For example, such a sequence may include as the variable heavy chain complementarity determining region 3 (HCDR3) a sequence that contains up to 1, 2, 3, or 4 amino acid substitutions within aCD38-b-348-HCDR3. In a further embodiment, the aCD38-b-348 amino acid sequence also refers to an antibody sequence comprising, as variable heavy chain complementarity determining regions 1, 2, and 3 (HCDR1, HCDR2, and HCDR3), aCD38-b-348-HCDR1, aCD38-b-348-HCDR2, and aCD38-b-348-HCDR3, a sequence comprising up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions, more preferably a sequence comprising up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions, within aCD38-b-348-HCDR123 (SEQ ID NO: 28) or within SEQ ID NO: 54. In some embodiments, the aCD38-b-348 amino acid sequence also refers to an antibody sequence that comprises, as a variable heavy chain sequence, a sequence that comprises up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions within the framework regions of the variable heavy chain sequence. Antibodies that display such aCD38-b-348 amino acid sequence elements and such substitutions may still display the binding and / or functional properties of aCD38-b-348, generally a CD38 modulating antibody agent.

[0138] Such aCD38-b-348 amino acid sequences may also include, as a variable light chain complementarity determining region 3 (LCDR3), a sequence that includes up to 1, 2, 3, or 4 amino acid substitutions within aCD38-b-348-LCDR3. In a further embodiment, the aCD38-b-348 amino acid sequence also refers to an antibody sequence that comprises, as variable light chain complementarity determining regions 1, 2, and 3 (LCDR1, LCDR2, and LCDR3), a sequence that contains up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions in aCD38-b-348-LCDR1, aCD38-b-348-LCDR2, and aCD38-b-348-LCDR3, more preferably a sequence that contains up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions in aCD38-b-348-LCDR123 (SEQ ID NO: 32) or in SEQ ID NO: 55. In some embodiments, the aCD38-b-348 amino acid sequence also refers to an antibody sequence that comprises, as a variable light chain sequence, a sequence that comprises up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions within the framework regions of the variable light chain sequence. Antibodies that display such aCD38-b-348 amino acid sequence elements and such substitutions may still display the binding and / or functional properties of aCD38-b-348, generally a CD38 modulating antibody agent.

[0139] Thus, in one embodiment, the invention provides an anti-CD38 antibody agent (i.e., an antibody or antigen-binding fragment thereof, and variants thereof as described herein, e.g., variants mutated to remove the DG motif) comprising: a. the variable heavy chain region sequence of aCD38-b-348 (or a variant thereof, e.g. an affinity matured variant thereof), or a variable heavy chain region sequence having up to five amino acid substitutions compared to the variable heavy chain region sequence of aCD38-b-348 (or a variant thereof, e.g. an affinity matured variant thereof), and / or b. The variable light chain region sequence of aCD38-b-348 (or a variant thereof, such as an affinity matured variant thereof), or a variable light chain region sequence having up to five amino acid substitutions compared to the variable light chain region sequence of aCD38-b-348 (or a variant thereof, such as an affinity matured variant thereof).

[0140] aCD38-b-348 heavy chains that may incorporate amino acid substitutions include SEQ ID NOs: 28 and 54. aCD38-b-348 light chains that may incorporate amino acid substitutions include SEQ ID NOs: 32, 55, 58, 59, 60, 61, 64, 65, 66, and 67.

[0141] Amino acid substitutions preferably do not adversely affect or do not substantially adversely affect the functional properties of the antibody.Therefore, these substitutions can be considered as conservative amino acid substitutions.Preferably, when amino acid substitutions occur, they occur in a 1:1 ratio so that the total length of the heavy and / or light chain variable regions does not change.

[0142] In one aspect, the present invention provides aCD38-a-327-HCDR3 amino acid sequence and polypeptides comprising same, such as antibodies or antigen-binding fragments comprising the aCD38-a-327-HCDR3 amino acid sequence (SEQ ID NO: 35) as variable heavy chain complementarity determining region 3. In some embodiments, such antibodies or antigen-binding fragments are a) the aCD38-a-327-HCDR1 amino acid sequence (SEQ ID NO: 33) as variable heavy chain complementarity determining region 1, and / or b) It may be further characterized by comprising additional aCD38-a-327 amino acid sequence elements, such as the aCD38-a-327-HCDR2 amino acid sequence (SEQ ID NO: 34) as variable heavy chain complementarity determining region 2.

[0143] In some embodiments, the provided antibodies or antigen-binding fragments thereof may further comprise the above-defined variable heavy chain complementarity determining regions (i.e., the aCD38-a-327 amino acid sequence elements) specifically separated by an antibody framework sequence, such as that contained in the aCD38-a-327-HCDR123 amino acid sequence (SEQ ID NO: 36), in the correct order, in particular to correctly exert their binding and functional properties. For example, in some embodiments, the provided antibodies or antigen-binding fragments thereof may comprise the aCD38-a-327-HCDR123 amino acid sequence (SEQ ID NO: 36, or the HCDR1, HCDR2, and HCDR3 sequences thereof), and optionally a) the aCD38-a-327-LCDR1 amino acid sequence (SEQ ID NO: 37) as variable light chain complementarity determining region 1; b) the aCD38-a-327-LCDR2 amino acid sequence (SEQ ID NO: 38) as variable light chain complementarity determining region 2, and c) It may comprise the aCD38-a-327-LCDR3 amino acid sequence (SEQ ID NO: 39) as variable light chain complementarity determining region 3.

[0144] Thus, in some embodiments, the invention provides an isolated antibody or antigen-binding fragment thereof comprising a variable heavy chain comprising the aCD38-a-327-HCDR123 amino acid sequence (SEQ ID NO: 36). Preferably, such an isolated antibody or antigen-binding fragment thereof further comprises a variable light chain comprising the aCD38-a-327-LCDR123 amino acid sequence (SEQ ID NO: 40), as described in the Examples.

[0145] In some embodiments, the present invention provides a method for the preparation of a nucleic acid having the sequence: JPEG2025028972000014.jpg16170, and / or a variable heavy chain comprising the sequence: The present invention provides an isolated antibody or antigen-binding fragment thereof comprising a variable light chain comprising JPEG2025028972000015.jpg16170.

[0146] In some embodiments, the variable heavy chain sequence of aCD38-a-327 has the sequence: JPEG2025028972000016.jpg22170, and the variable light chain sequence of aCD38-a-327 is the sequence: Contains JPEG2025028972000017.jpg17170.

[0147] The present invention also provides an antibody or antigen-binding fragment thereof comprising the sequence of aCD38-a-327-HCDR3 as HCDR3 and the sequence of aCD38-a-327-LCDR3 as LCDR3.

[0148] The present invention also provides variant antibodies and antigen-binding fragments thereof having a certain percent identity to a reference sequence, such as the CDR sequence or heavy or light chain variable sequence of aCD38-a-327. Such antibodies and antigen-binding fragments thereof may also be referred to herein as CD38 modulating antibody agents.

[0149] For example, in some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 56. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 56. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 56. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising the amino acid sequence of SEQ ID NO:56.

[0150] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 57. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 57. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 57. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising the amino acid sequence of SEQ ID NO: 57.

[0151] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO:56 and a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO:57. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO:56 and a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO:57. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:56 and a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO:57. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising the amino acid sequence of SEQ ID NO:56 and a variable light chain sequence comprising the amino acid sequence of SEQ ID NO:57.

[0152] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 76. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 76. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 76. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising the amino acid sequence of SEQ ID NO: 76.

[0153] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 77. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 77. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 77. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising the amino acid sequence of SEQ ID NO: 77.

[0154] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 76 and a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 77. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 76 and a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 77. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 76 and a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 77. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence of SEQ ID NO: 76 and a variable light chain sequence comprising an amino acid sequence of SEQ ID NO: 77.

[0155] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 36. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 36. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 36. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising the amino acid sequence of SEQ ID NO: 36.

[0156] In some embodiments, the anti-CD38 antibody, or antigen-binding fragment thereof, comprises a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 40. In some embodiments, the anti-CD38 antibody, or antigen-binding fragment thereof, comprises a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 40. In some embodiments, the anti-CD38 antibody, or antigen-binding fragment thereof, comprises a variable light chain sequence comprising an amino acid sequence having at least 98 ... The anti-CD38 antibody or antigen-binding fragment thereof comprises a variable light chain sequence comprising the amino acid sequence of SEQ ID NO:40.

[0157] In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 36 and a variable light chain sequence comprising an amino acid sequence having at least 90% sequence identity to SEQ ID NO: 40. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 36 and a variable light chain sequence comprising an amino acid sequence having at least 95% sequence identity to SEQ ID NO: 40. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 36 and a variable light chain sequence comprising an amino acid sequence having at least 98% sequence identity to SEQ ID NO: 40. In some embodiments, the anti-CD38 antibody or antigen-binding fragment thereof comprises a variable heavy chain sequence comprising an amino acid sequence of SEQ ID NO: 36 and a variable light chain sequence comprising an amino acid sequence of SEQ ID NO: 40.

[0158] Such variant antibodies and antigen-binding fragments thereof may retain or exhibit the same (or substantially the same) functional and pharmacological properties as described for antibodies and antigen-binding fragments thereof having the heavy and light chain variable sequences disclosed herein for aCD38-a-327.

[0159] Furthermore, aCD38-a-327 amino acid sequence also refers to an antibody sequence defined by the number of substitutions to the aCD38-a-327 amino acid sequence elements defined above. For example, such a sequence may include, as the variable heavy chain complementarity determining region 3 (HCDR3), a sequence that contains up to 1, 2, 3, or 4 amino acid substitutions within aCD38-a-327-HCDR3. In a further embodiment, the aCD38-a-327 amino acid sequence also refers to an antibody sequence comprising, as variable heavy chain complementarity determining regions 1, 2, and 3 (HCDR1, HCDR2, and HCDR3), aCD38-a-327-HCDR1, aCD38-a-327-HCDR2, and aCD38-a-327-HCDR3, a sequence comprising up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions, more preferably a CD38-a-27-HCDR123 (SEQ ID NO: 36) or SEQ ID NO: 56 or SEQ ID NO: 76. In some embodiments, the aCD38-a-327 amino acid sequence also refers to an antibody sequence that comprises, as a variable heavy chain sequence, a sequence that comprises up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions within the framework regions of the variable heavy chain sequence. Antibodies that display such aCD38-a-327 amino acid sequence elements and such substitutions may still display the binding and / or functional properties of aCD38-a-327, generally a CD38 modulating antibody agent.

[0160] Such aCD38-a-327 amino acid sequence may also include, as variable light chain complementarity determining region 3 (LCDR3), a sequence that includes up to 1, 2, 3, or 4 amino acid substitutions within aCD38-a-327-LCDR3. In a further embodiment, the aCD38-a-327 amino acid sequence also refers to an antibody sequence comprising, as variable light chain complementarity determining regions 1, 2, and 3 (LCDR1, LCDR2, and LCDR3), aCD38-a-327-LCDR1, aCD38-a-327-LCDR2, and aCD38-a-327-LCDR3, a sequence containing up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions, more preferably aCD38-a-327-LCDR123 (SEQ ID NO: 40) or a sequence containing up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions, in SEQ ID NO: 57 or SEQ ID NO: 77. In some embodiments, the aCD38-a-327 amino acid sequence also refers to an antibody sequence that includes, as a variable light chain sequence, a sequence that contains up to 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions within the framework regions of the variable light chain sequence. Antibodies displaying such aCD38-a-327 amino acid sequence elements and such substitutions may still display the binding and / or functional properties of aCD38-a-327, and generally CD38 modulating antibody agents.

[0161] Thus, in one embodiment, the invention provides an anti-CD38 antibody agent (i.e., an antibody or antigen-binding fragment thereof, and variants thereof as described herein, e.g., variants mutated to remove the DG motif) comprising: a. the variable heavy chain region sequence of aCD38-a-327 (or a variant thereof, e.g. an affinity matured variant thereof), or a variable heavy chain region sequence having up to five amino acid substitutions compared to the variable heavy chain region sequence of aCD38-a-327 (or a variant thereof, e.g. an affinity matured variant thereof), and / or b. The variable light chain region sequence of aCD38-a-327 (or a variant thereof, e.g., an affinity matured variant thereof), or a variable light chain region sequence having up to five amino acid substitutions compared to the variable light chain region sequence of aCD38-a-327 (or a variant thereof, e.g., an affinity matured variant thereof).

[0162] The aCD38-a-327 heavy chains that may incorporate amino acid substitutions include SEQ ID NOs: 36, 56, and 76. The aCD38-a-327 light chains that may incorporate amino acid substitutions include SEQ ID NOs: 40, 57, and 77.

[0163] Amino acid substitutions preferably do not adversely affect or do not substantially adversely affect the functional properties of the antibody.Therefore, these substitutions can be considered as conservative amino acid substitutions.Preferably, when amino acid substitutions occur, they occur in a 1:1 ratio so that the total length of the heavy and / or light chain variable regions does not change.

[0164] Thus, the present invention also provides variant antibodies or antigen-binding fragments of the antibodies described herein.The present invention provides antibodies or antigen-binding fragments thereof in which any DG motif in the light or heavy chain of the antibody can be modified, for example, to reduce aspartic acid isomerization, and / or any methionine in the light or heavy chain of the antibody can be modified, for example, to reduce methionine oxidation.For example, the DG motif can be modified to replace one or both of the amino acids in the motif with a different amino acid.For example, such motifs can be mutated to EG, DQ, or DA.The methionine residue can be modified to replace it with a different amino acid, for example, leucine or phenylalanine.

[0165] In such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof may be or may be derived from, for example, aCD38-b-348 or aCD38-b-329, although variants of all of the antibodies disclosed herein are specifically contemplated and provided. Variant anti-CD38 antibodies provide additional antibodies having the binding and functional characteristics of any, and possibly all, of aCD38-b-348 and aCD38-b-329.

[0166] Thus, in some embodiments, the antibodies or fragments thereof provided herein may be mutated to remove or modify DG motifs, particularly those occurring within the CDR regions, to reduce susceptibility to aspartic acid isomerization, as is standard in the art. Such antibodies modified in this way may need to undergo further modifications (e.g., affinity maturation) before arriving at the final sequence.

[0167] In one embodiment of the invention, the CDR1, CDR2, and CDR3 sequences of an antibody disclosed herein (e.g., any of aCD38-a-323, aCD38-b-329, aCD38-b-348, aCD38-a-306, or aCD38-a-327) are used. Variant antibodies are provided that have sequences that differ from the specified sequences of the CDRs (e.g., the CDR1, CDR2, and CDR3 sequences of any of aCD38-a-323, aCD38-b-329, aCD38-b-348, aCD38-a-306, or aCD38-a-327), or the variable heavy and variable light chains of any of the antibodies disclosed herein (e.g., the variable heavy and variable light chains of any of aCD38-a-323, aCD38-b-329, aCD38-b-348, aCD38-a-306, or aCD38-a-327), but in which at least one or at least two DG motifs within the CDRs (if present) have been changed to different motifs. The disclosed variants can be used and formulated as described for any of aCD38-a-323, aCD38-b-329, aCD38-b-348, aCD38-a-306, or aCD38-a-327.

[0168] For example, aCD38-b-329 contains a DG motif within its LCDR3 sequence. In some embodiments, the aspartic acid of the DG motif may be changed to a different amino acid and / or the glycine of the DG motif may be changed to a different amino acid. In such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof may be, or may be derived from, e.g., aCD38-b-329. In some of these embodiments, the variant antibody or antigen-binding fragment thereof has the VL CDR3 sequences provided in Table 5 (labeled aCD38-b-329-m6 and aCD38-b-329-m7). For example, a variant LCDR3 sequence (e.g., the aCD38-b-329-m6 variant LCDR3 sequence or the aCD38-b-329-m7 variant LCDR3 sequence) may be incorporated into an antibody that contains the LCDR1 and / or LCDR2 sequences of aCD38-b-329. In one embodiment, a variant LCDR3 sequence (e.g., aCD38-b-329-m6 variant LCDR3 sequence or aCD38-b-329-m7 variant LCDR3 sequence) may be incorporated into an antibody that comprises the LCDR1, LCDR2, HCDR1, HCDR2, and HCDR3 sequences of aCD38-b-329. In some embodiments, a variant antibody or antibody binding fragment thereof may comprise the variable heavy and variable light chain sequences of aCD38-b-329, but with the LCDR3 sequence mutated to remove the DG motif (e.g., aCD38-b-329-m6-LCDR3 or aCD38-b-329-m7-LCDR3 may be present instead as the LCDR3). Variant anti-CD38 antibodies provide additional antibodies with any and possibly all of the binding and functional properties of the parent aCD38-b-329. The disclosed variants can be used and formulated as described for aCD38-b-329.

[0169] Therefore, the variant antibody aCD38-b-329-m6 A heavy chain variable region comprising the sequence of JPEG2025028972000018.jpg21170, and JPEG2025028972000019.jpg16170.

[0170] The variant antibody aCD38-b-329-m7 is A heavy chain variable region comprising the sequence of JPEG2025028972000020.jpg24170, and JPEG2025028972000021.jpg17170.

[0171] The antibody aCD38-b-348 contains a DG motif within its LCDR3 sequence. In some embodiments, the aspartic acid of the DG motif may be changed to a different amino acid and / or the glycine of the DG motif may be changed to a different amino acid. In such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof may be, or may be derived from, e.g., aCD38-b-348. In some of these embodiments, the variant antibody or antigen-binding fragment thereof has the VL CDR3 sequences provided in Table 8 (labeled aCD38-b-348-m1, aCD38-b-348-m2, aCD38-b-348-m3, and aCD38-b-348-m4). For example, a variant LCDR3 sequence (e.g., an aCD38-b-348-m1 variant LCDR3 sequence, an aCD38-b-348-m2 variant LCDR3 sequence, an aCD38-b-348-m3 variant LCDR3 sequence, or an aCD38-b-348-m4 variant LCDR3 sequence) can be incorporated into an antibody that comprises the LCDR1 and / or LCDR2 sequences of aCD38-b-348. In one embodiment, a variant LCDR3 sequence (e.g., aCD38-b-348-m1 variant LCDR3 sequence, aCD38-b-348-m2 variant LCDR3 sequence, aCD38-b-348-m3 variant LCDR3 sequence, or aCD38-b-348-m4 variant LCDR3 sequence) may be incorporated into an antibody that comprises the LCDR1, LCDR2, HCDR1, HCDR2, and HCDR3 sequences of aCD38-b-348. In some embodiments, variant antibodies or antibody binding fragments thereof may comprise the variable heavy and variable light chain sequences of aCD38-b-348, but where the LCDR3 sequence has been mutated to remove the DG motif (e.g., aCD38-b-348-m1-LCDR3, aCD38-b-348-m2-LCDR3, aCD38-b-348-m3-LCDR3, or aCD38-b-348-m4-LCDR3 may instead be present as the LCDR3). Variant anti-CD38 antibodies provide additional antibodies with any and possibly all of the binding and functional properties of the parent aCD38-b-348.The disclosed variants can be used and formulated as described for aCD38-b-348.

[0172] Therefore, the variant antibody aCD38-b-348-m1 A heavy chain variable region comprising the sequence of JPEG2025028972000022.jpg22170, and JPEG2025028972000023.jpg16170.

[0173] The variant antibody aCD38-b-348-m2 is A heavy chain variable region comprising the sequence of JPEG2025028972000024.jpg23170, and JPEG2025028972000025.jpg17170

[0174] The variant antibody aCD38-b-348-m3 is A heavy chain variable region comprising the sequence of JPEG2025028972000026.jpg23170, and JPEG2025028972000027.jpg17170.

[0175] The variant antibody aCD38-b-348-m4 is A heavy chain variable region comprising the sequence of JPEG2025028972000028.jpg24170, and JPEG2025028972000029.jpg16170.

[0176] The present invention also provides affinity matured antibodies, such as affinity matured variants derived from any of the antibodies disclosed herein. In one embodiment, the affinity matured antibody is an affinity matured antibody that further has a modified DG motif and / or NG motif and / or is modified to remove or mutate any methionine residue. The disclosed affinity matured variants can be used and formulated as described for any of aCD38-a-323, aCD38-b-329, aCD38-b-348, aCD38-a-306, or aCD38-a-327.

[0177] In some embodiments, the invention provides a method of preparing an anti-CD38 antibody, the method comprising providing an antibody described herein (e.g., aCD38-a-323, aCD38-b-329, aCD38-b-348, aCD38-a-306, or aCD38-a-327, or an antigen-binding fragment or variant thereof) and binding the antibody to an affinity construct. and subjecting the produced antibody to maturation, whereby the produced antibody binds to CD38 with a higher affinity than the parent antibody. Preferably, the produced antibody binds to CD38 with at least 20%, at least 30%, at least 40%, more preferably at least 50% higher affinity than the parent antibody that binds to CD38, e.g., as measured by Kd. Methods for measuring affinity are known in the art and are described in the Examples below. Affinity matured antibodies produced by such methods can be formulated and used as described herein for other anti-CD38 antibody agents.

[0178] Affinity maturation can be carried out according to any suitable method known to those skilled in the art. For example, in vitro antibody display systems are widely used to generate specific antibodies with high affinity. In these systems, the phenotype (i.e., antibody fragments) is combined with the genotype (i.e., antibody genes) to allow direct determination of the antibody sequence. Several systems have been developed that achieve the display of antibody repertoires and allow subsequent selection of binders, allowing the selection of variants with progressively higher affinities by increasing the selection stringency. Antibody fragments can be expressed in yeast, on ribosomes, on phage display particles, or by direct binding to DNA.

[0179] Current antibody affinity maturation methods belong to two mutagenesis categories: stochastic and non-stochastic. Error-prone polymerase chain reaction (PCR), mutagen bacterial strains, and saturation mutagenesis are typical examples of stochastic mutagenesis methods. Non-stochastic techniques often use alanine scanning or site-directed mutagenesis to generate a limited collection of specific variants. In addition, shuffling approaches to obtain shuffled variants of a parent antibody can also be used to further improve antibody affinity.

[0180] Thus, in one embodiment of the invention, the affinity maturation method is selected from the group consisting of stochastic mutagenesis (e.g., error-prone polymerase chain reaction (PCR), mutagen bacterial strains, or saturation mutagenesis), non-stochastic mutagenesis (e.g., alanine scanning or site-directed mutagenesis), shuffling (e.g., DNA shuffling, chain shuffling, or CDR shuffling), and use of the CRISPR-Cas9 system to introduce modifications.

[0181] Affinity maturation methods are described, for example, in Rajpal et al., Proc Natl Acad Sci USA, 2005, 102(24):8466-71, Steinwand et al. et al., MAbs, 2014, 6(1):204-18, and Therapeutic Antibodies, Wiley, 2014, Chapter 6, Antibody Affinity (pp. 115-140).

[0182] In some embodiments, a method of preparing a pharmaceutical composition is provided, the method comprising providing an antibody prepared according to the above method (i.e., a method for producing an antibody by affinity maturation) and co-formulating the antibody with at least one or more pharma- ceutically acceptable excipients. The antibody used to prepare the pharmaceutical composition can be an affinity matured variant of aCD38-a-323, aCD38-b-329, aCD38-b-348, aCD38-a-306, or aCD38-a-327. The pharmaceutical composition produced by such a method can be used in the therapeutic methods of the invention described herein for other anti-CD38 antibody agents.

[0183] Antibodies and / or antigen-binding fragments thereof described herein (e.g., one or more aCD38-a-323 amino acid sequence elements, e.g., aCD38-a-323-HCDR3 or aCD38-a-323-HCDR123, one or more aCD38-a-306 amino acid aCD38-a-306-HCDR3 or aCD38-a-306-HCDR123, one or more aCD38-b-329 amino acid sequence elements, e.g., aCD38-b-329-HCDR3 or aCD38-b-329-HCDR123, one or more aCD38-b-348 amino acid sequence elements, e.g., aCD38-b-348-HCDR3 or aCD38-b-348-HCDR123, one or more aCD38-a-327 amino acid sequence elements, e.g., The CD38 modulating antibody agent (which may include an acid sequence element, e.g., aCD38-a-327-HCDR3 or aCD38-a-327-HCDR123, and / or may compete with aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-b-348, or aCD38-a-327 for binding to human CD38 and non-human primate CD38, e.g., cynomolgus monkey CD38, etc.) may be provided in any of a variety of formats. For example, in some embodiments, a suitable format may be or include a monoclonal antibody, a domain antibody, a single chain antibody, a Fab fragment, a F(ab')2 fragment, a single chain variable fragment (scFv), a scFv-Fc fragment, a single chain antibody (scAb), an aptamer, or a single domain antibody. In some embodiments, the antibody or antigen-binding fragment thereof (and specifically the monoclonal antibody) may be a rabbit, mouse, chimeric, humanized, or fully human antibody or antigen-binding fragment thereof. In some embodiments, the antibody or antigen-binding fragment thereof provided may be of the IgG, IgA, IgE, or IgM isotype (preferably human), as may be most appropriate. In some embodiments, the antibody or antigen-binding fragment thereof provided may be of the IgG isotype, more specifically, the IgG1, IgG2, IgG3, or IgG4 isotype (preferably human IgG1).In some embodiments, the provided antibodies or antigen-binding fragments thereof may be provided as part of a multispecific binding agent (e.g., when it is desirable to conjugate additional binding moieties and / or functional moieties to a CD38 modulating antibody agent such as aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-b-348, or aCD38-a-327 amino acid sequence), and the isolated antibody or antigen binding may be included in a bispecific antibody, a multispecific antibody, or other multispecific format that may be available in the art.

[0184] In some embodiments, the provided CD38 modulating antibody agent comprises a CD38 binding entity (e.g., an anti-CD38 antibody or an antigen-binding fragment thereof) and a conjugated payload, e.g., a therapeutic or diagnostic agent. In many such embodiments, the agent is considered and / or referred to as an "immunoconjugate". Examples of techniques and compounds that can be used to generate certain immunoconjugates, such as antibody-drugs, are described in the literature (Beck A et al., 2017) and are described as applicable to several known anti-CD38 antibodies (WO2016 / 166304).

[0185] In some embodiments, the invention provides aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-b-348, or aCD38-a-327 amino acid sequences that identify the provided antibodies or antigen-binding fragments thereof. In some embodiments, such sequences identify the provided antibodies or antigen-binding fragments thereof that bind to an epitope within the extracellular domain of human CD38 (e.g., aCD38-b-ep for aCD38-b-348 and aCD38-b-329, or aCD38ep-a and aCD38ep-b for CD38-a-327), and optionally also bind to the corresponding epitope on cynomolgus monkey and / or mouse CD38, either as an isolated protein or on the surface of cells expressing CD38 (such as immune cells or cell lines, e.g., Raji cells).

[0186] The present invention also provides CD38 modulating antibody agents that bind the same (or a similar) epitope as that bound by a CD38 modulating antibody agent of the present invention. For example, in one embodiment Provided herein are antibodies that bind to the same (or similar) epitope as (aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-b-348, or aCD38-a-327 (or variants thereof)).

[0187] In some embodiments, the invention provides an anti-CD38 antibody or antigen-binding fragment that specifically binds to an epitope of human CD38, the epitope comprising one or more amino acid residues contained within amino acids 65-79 of SEQ ID NO:47 (i.e., aCD38-b-ep). In such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof can be, or can be derived from, e.g., aCD38-b-348 or aCD38-b-329. Preferably, the epitope comprises at least four amino acids, the epitope comprising one or more amino acids contained within amino acids 65-79 of SEQ ID NO:47. Preferably, the epitope comprises at least five amino acids, at least six amino acids, at least seven amino acids, at least eight amino acids, at least nine amino acids, at least ten amino acids, at least eleven amino acids, at least twelve amino acids, at least thirteen amino acids, or at least fourteen or more amino acids, the epitope comprising one or more amino acids contained within amino acids 65-79 of SEQ ID NO:47. The epitope can be either linear or conformational, i.e., discontinuous. In some embodiments, the anti-CD38 antibody or antigen-binding fragment specifically binds to an epitope of human CD38 that includes at least 2, at least 3, at least 4, at least 5, at least 6, at least 7, at least 8, at least 9, at least 10, at least 11, at least 12, at least 13, or at least 14 or more amino acid residues contained within amino acids 65-79 of SEQ ID NO:47. In some embodiments, the anti-CD38 antibody or antigen-binding fragment binds to an epitope that includes amino acids 65-79 of SEQ ID NO:47.

[0188] In some embodiments, the invention provides anti-CD38 antibodies or antigen-binding fragments that specifically bind to an epitope of human CD38, the epitope comprising one or more amino acid residues contained within amino acids 47-66 and 126-138 of SEQ ID NO:47 (i.e., aCD38ep-a and aCD38ep-b). In such embodiments, the anti-CD38 antibody or antigen-binding fragment thereof can be, or can be derived from, for example, aCD38-a-327. Preferably, the epitope comprises at least four amino acids, the epitope comprising one or more amino acids contained within amino acids 47-66 and 126-138 of SEQ ID NO:47. Preferably, the epitope comprises at least 5 amino acids, at least 6 amino acids, at least 7 amino acids, at least 8 amino acids, at least 9 amino acids, at least 10 amino acids, at least 11 amino acids, at least 12 amino acids, at least 13 amino acids, or at least 14 or more amino acids, the epitope comprising one or more amino acids contained within amino acids 47-66 and 126-138 of SEQ ID NO: 47. The epitope can be either linear or conformational, i.e., discontinuous. In some embodiments, the anti-CD38 antibody or antigen-binding fragment specifically binds to an epitope of human CD38, the epitope comprising at least 2, at least 3, at least 4, at least 5, at least 6, at least 7, at least 8, at least 9, at least 10, at least 11, at least 12, at least 13, or at least 14 or more amino acid residues contained within amino acids 47-66 and 126-138 of SEQ ID NO: 47. In some embodiments, the anti-CD38 antibody or antigen-binding fragment binds to an epitope that includes amino acids 47-66 and 126-138 of SEQ ID NO: 47. In some embodiments, the anti-CD38 antibody or antigen-binding fragment further binds to amino acid 68 of SEQ ID NO: 47.

[0189] In some embodiments, the present invention provides an antibody that specifically binds to an epitope of human CD38. An anti-CD38 antibody or antigen-binding fragment is provided, the epitope comprising amino acids 120, 121, and 141 of SEQ ID NO: 47. In some embodiments, the anti-CD38 antibody or antigen-binding fragment further binds to amino acid 241 of SEQ ID NO: 47. In such embodiments, the anti-CD38 antibody or antigen-binding fragment may be or be derived from, for example, aCD38-a-323.

[0190] In some embodiments, the present invention relates to an epitope that is specific to an epitope identified in the Examples as aCD38-b-ep (protein sequence ARCVKYTEIHPEMRH, amino acids 65-79 in Uniprot sequence P28907, SEQ ID NO: 47) for CD38-b-348 and aCD38b-329 (or variants thereof), and aCD38ep-a (protein sequence RQQWSGPGTT aCD38-a-323, aCD38-a-306, aCD38-a-327, aCD38-a-308, aCD38-a-329, aCD38-b-kRFPETVLAR (amino acids 47-66 in Uniprot sequence P28907, SEQ ID NO: 47) and aCD38ep-b (protein sequence SRIKDLAHQFTQV, amino acids 126-138 in Uniprot sequence P28907, SEQ ID NO: 47) as isolated proteins that compete for the epitope identified and that allow binding to the human CD38 extracellular domain on the surface of cells expressing human CD38. aCD38-a-323-HCDR3 amino acid sequence and / or exhibits binding characteristics equivalent to an antibody or antigen-binding fragment thereof that comprises one or more aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-b-348, or aCD38-a-327 amino acid sequence elements (e.g., comprises the aCD38-a-323-HCDR3 amino acid sequence and / or competes with aCD38-a-323 and aCD38-a-306-HCDR3 amino acid sequence). The present invention provides a procedure for screening and / or characterizing antibodies or antigen-binding fragments thereof that comprise aCD38-a-306, aCD38-b-329-HCDR3 amino acid sequence, and / or compete with aCD38-b-329, aCD38-b-348-HCDR3 amino acid sequence, and / or compete with aCD38-b-348, and aCD38-a-327-HCDR3 amino acid sequence, and / or compete with aCD38-a-327. The antibody aCD38-a-327 (or a variant thereof) may further bind to amino acid 68 of SEQ ID NO:47.The antibody aCD38-a-323 (or a variant thereof) may bind to an epitope including amino acid residues 120, 121, and 141 of SEQ ID NO:47, and may optionally bind to amino acid residue 241 of SEQ ID NO:47.

[0191] Furthermore, the present invention also provides procedures for screening for antibodies or antigen-binding fragments thereof that exhibit functional characteristics equivalent to those of antibodies or antigen-binding fragments thereof that contain one or more aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-b-348, or aCD38-a-327 amino acid sequence elements, such characteristics being cell activation and cytotoxicity activity, which play a role as CD38-modulating antibody agents. To this extent, candidate antibodies can be tested in the assays described in the Examples (see, for example, FIG. 1) or other assays known in the art to establish the presence of any, but possibly all, of such characteristics when evaluated in in vitro / ex vivo assays, cell-based assays, and / or animal models.

[0192] In some embodiments, the invention provides nucleic acid molecules encoding isolated antibodies or antigen-binding fragments thereof comprising CD38 modulating antibody agents such as aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-b-348, or aCD38-a-327 amino acid sequences or variants thereof. In some embodiments, such provided nucleic acid molecules may comprise codon-optimized nucleic acid sequences and / or may be contained in an expression cassette within a nucleic acid vector suitable for expression in a host cell, such as, for example, a yeast, insect, fish, mouse, monkey, or human cell.

[0193] In some embodiments, the present disclosure provides host cells comprising a heterologous nucleic acid molecule (e.g., a DNA vector) expressing a provided CD38 modulating antibody agent (e.g., an antibody or antigen-binding fragment thereof) having one or more properties of a CD38 modulating antibody agent (e.g., comprising aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-b-348, or aCD38-a-327 amino acid sequence or variants thereof), e.g., a property described herein. In some embodiments, the present disclosure provides methods of preparing a CD38 modulating antibody agent (e.g., an antibody or antigen-binding fragment thereof) having one or more properties of a CD38 modulating antibody agent (e.g., comprising aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-b-348, or aCD38-a-327 amino acid sequence or variants thereof), e.g., a property described herein. In some embodiments, such methods may include culturing host cells that contain nucleic acid (e.g., heterologous nucleic acid that may include a vector and / or be delivered to a host cell via a vector). In some embodiments, such host cells (and / or heterologous nucleic acid sequences) are positioned and constructed such that the CD38 modulating antibody agent (e.g., the present antibody or antigen-binding fragment thereof) is secreted from the host cell (e.g., so that it can be isolated from a cell culture supernatant) and / or exposed to the cell surface (e.g., when such aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-b-348, or aCD38-a-327 amino acid sequences (or variants thereof) and sequence elements are used in the context of, or intended to be used with, such cells, as found in artificial T cell receptors that graft the specificity of a monoclonal antibody onto T cells).

[0194] In some embodiments, the antibody or its antigen-binding fragment (or its variant) may be defucosylated. It is well known that antibody glycosylation can affect the activity, pharmacokinetics, and pharmacodynamics of an antibody (e.g., a monoclonal antibody, a recombinant antibody, and / or an antibody that is otherwise engineered or isolated), and that Fc fusion proteins and certain techniques can be used to obtain an antibody with a desired glycosylation profile (Liu L, 2015). The effector function that supports the cytotoxicity of an antibody for use according to the present invention (e.g., an anti-CD38 antibody described herein, including an antibody that can be or can be a CD38-modulating antibody drug) can be enhanced using a method that reduces the fucosylation level of the antibody. Antibodies comprising specific aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327 or aCD38-b-348 sequence elements exhibiting such properties can be produced, for example, by expressing the aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327 or aCD38-b-348 sequence using techniques for genetically engineering cell lines capable of producing antibodies with no or reduced fucosylation capacity (some of which are commercially available (Potelligent (Lonza) GlyMAXX (ProBiogen) etc.)) or by manipulating the production process, for example by controlling osmolality and / or by using enzyme inhibitors, see also the methods described in, for example, EP2480671.

[0195] In some embodiments, the invention provides compositions (e.g., pharmaceutical compositions) comprising the provided antibodies or antigen-binding fragments thereof having desirable properties as described herein (e.g., specifically as described herein for antibodies referred to as CD38 modulating antibody agents, including, e.g., aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348 antibodies or antigen-binding fragments thereof, and variants thereof). In some embodiments, such provided compositions are intended for and / or have a medical use, such as therapeutic, diagnostic, or prophylactic use. In some embodiments, such provided compositions may further comprise a pharma- ceutically acceptable carrier or excipient and / or may be for use in the treatment of cancer. In some embodiments, the pharmaceutical compositions may be formulated with one or more carriers, excipients, salts, buffers, etc., as known in the art. Those skilled in the art will recognize and can readily utilize a variety of formulation techniques, including those that may be particularly desirable and / or useful for a given method and / or site of administration, e.g., parenteral administration (e.g., subcutaneous, intramuscular, or intravenous injection), mucosal, intratumoral, peritumoral, oral, or topical administration. In many embodiments, the provided pharmaceutical compositions comprising the CD38 modulating antibody agents (e.g., anti-CD38 antibodies or antigen-binding portions thereof) described herein are formulated for parenteral delivery (e.g., by injection and / or infusion). In some embodiments, such provided pharmaceutical compositions may be provided, for example, in a prefilled syringe or vial format. In some embodiments, such provided pharmaceutical compositions may be provided and / or utilized, for example, in a dried (e.g., lyophilized) form, or in some embodiments, such provided pharmaceutical compositions may be provided and / or utilized in a liquid form (e.g., a solution, suspension, dispersion, emulsion, etc.), a gel form, etc.

[0196] In some embodiments, the invention relates to the use of CD38 modulating antibody agents (e.g., anti-CD38 antibodies or antigen-binding fragments thereof) described herein (e.g., comprising aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348 amino acid sequence element), and / or compositions comprising same, for the treatment of cancer, e.g., B-cell malignancies, lymphomas, (Hodgkin's lymphoma, non-Hodgkin's lymphoma, chronic lymphocytic leukemia, acute lymphocytic leukemia, myeloma), myeloproliferative disorders, solid tumors (e.g., breast cancer, carcinoma, squamous cell carcinoma, colon cancer, head and neck cancer, lung cancer, genitourinary cancer, rectal cancer, gastric cancer, sarcoma, melanoma, esophageal cancer, liver cancer, testicular cancer, cervical cancer, mast cell tumor, hemangioma, eye cancer, laryngeal cancer, oral cancer, mesothelioma, skin cancer, rectal cancer, throat cancer, bladder cancer, breast cancer, uterine cancer, prostate cancer, lung cancer, pancreatic cancer, kidney cancer, gastric cancer, non-small cell lung cancer, and ovarian cancer. The above cancers can also be defined based on the presence of certain tumor-associated markers and antigens, such as CD20, HER2, PD-1, PD-L1, SLAM7F, CD47, CD137, CD134, TIM3, CD25, CD38, GITR, EGFR, etc., or cancers identified as having biomarkers called microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR). Furthermore, such conditions can also be considered in defining pre-cancerous non-invasive conditions of the above cancers, such as intraepithelial carcinoma, smoldering myeloma, monoclonal gammopathy of undetermined significance, cervical intraepithelial carcinoma, MALTomas / GALTomes, and various lymphoproliferative disorders. Preferably, in some embodiments, the subject to be treated has a solid tumor. In one embodiment, the subject has a hematological cancer. In some embodiments, the subject has a CD38-positive tumor.

[0197] Thus, in some embodiments, the present invention provides a method of treating cancer in a subject, the method comprising administering to the subject an effective amount of a composition comprising a provided CD38 modulating antibody agent (e.g., an anti-CD38 antibody or antigen-binding fragment thereof) as described herein (e.g., comprising aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348 amino acid sequence or variants thereof). In some embodiments, the provided method may further comprise administering to the subject at least one additional agent or therapy simultaneously or sequentially in any order (i.e., such that the subject receives a combination therapy). In some embodiments, such at least one additional agent or therapy is an anti-cancer agent (e.g., a chemotherapeutic agent), radiation therapy (by applying X-ray radiation externally to the body or by administering a radioconjugated compound), an anti-tumor antigen or marker antibody (e.g., an antigen or The marker may be or may include CD4, CD25, CA125, PSMA, c-MET, VEGF, CD137, VEGFR2, CD20, HER2, HER3, SLAMF7, CD326, CAIX, CD40, CD47, or EGF receptor), a checkpoint inhibitor or immune modulating antibody (e.g., an antibody targeting PD-1, PD-L1, TIM3, CD25, GITR, CD134, CD134L, CD137L, CD80, CD86, B7-H3, B7-H4, B7RP1, LAG3, ICOS, TIM3, GAL9, CD28, AP2M1, SHP-2, OX-40, etc.), a vaccine, an adjuvant, a standard of use protocol, one or more other compounds that target or stimulate an immune response against cancer cells, or any combination thereof. In certain specific embodiments, when such at least one additional agent or therapy is or comprises an antibody, the type of such antibody and / or the antigen targeted by such antibody may be selected from those listed in the literature and possibly tailored to a given cancer (Sliwkowski M & Mellman I, 2013; Redman JM et al., 2015; Kijanka M et al., 2015).

[0198] Still further, the present invention provides various kits or articles of manufacture comprising the provided CD38 modulating antibody agents (e.g., anti-CD38 antibodies or antigen-binding fragments thereof) described herein (e.g., comprising aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348 amino acid sequences or variants thereof), or related compositions that allow for the administration, storage, or other use of such isolated antibodies or antigen-binding fragments. In some embodiments, the provided kits include a vessel, syringe, vial, or other container that contains such compositions, optionally together with one or more articles of manufacture, diluents, reagents, solid phases, and / or instructions for the proper use of the kit.

[0199] In some embodiments, identification, characterization, and / or validation of a particular CD38 modulating antibody agent (e.g., an anti-CD38 antibody or antigen-binding fragment thereof) described herein (e.g., comprising aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348 amino acid sequence or variants thereof) for a particular use, such as a medical use, in particular for treating cancer, may be performed by using one or more assays or systems described herein. In some embodiments, such identification, characterization, and / or validation may include analysis of activity in one or more cell-based assays, for example, using different experimental settings and / or selected panels (e.g., cancer-derived cell lines). In some embodiments, particularly considering the activity of certain desired CD38 modulating antibody agents in relation to the proposed immunological mechanisms described herein, the desired identification, characterization, and / or validation may include collection of relevant data generated in animal models in which cancer is induced or in which cancer cells are transplanted as xenografts or cells from syngeneic / allogeneic cancers. Alternatively, or in addition, in some embodiments, animal models involving transplantation of human cells, such as PBMCs (i.e., humanized PBMC mouse models) or CD34+ hematopoietic stem cells (i.e., CD34+ humanized mice) may be utilized to allow for evaluation of the activity of CD38 modulating antibody agents on human immune cells in a model system.

[0200] In some embodiments, the relevant sequences of a CD38 modulating antibody agent (e.g., an anti-CD38 antibody or antigen-binding fragment thereof) described herein (e.g., comprising the aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348 amino acid sequence (or a variant thereof) or otherwise comprising the structural and / or functional characteristics of an agent described herein as a CD38 modulating antibody agent) may be cloned in the context of and / or expressed in an antibody framework that is more suitable or desirable for pharmaceutical and / or technical reasons. For example, such sequences may be The sequences (possibly as codon-optimized VH and VL coding sequences) can be cloned together with a human IgG1 constant region (hIgG1) and expressed using an appropriate antibody expression vector and cell line (such as a CHO-derived cell line, e.g., CHO-S). In some specific embodiments, expression and secretion of the provided antibody sequences in human IgG1 format antibodies can be analyzed after transfection under reducing conditions in cell lysates and non-reducing conditions in the supernatant, which are subsequently used to purify the antibody (by affinity chromatography, gel filtration, and / or other suitable techniques). Binding and / or other functional properties of the provided anti-CD38 antibody sequences in human IgG1 format (e.g., CD38 modulating antibody agent-hIgG1) can be analyzed, for example, by using one or more of the assays described in the Examples below. For example, such provided antibodies in hIgG1-format can be assessed for binding to human and cynomolgus monkey PBMCs, for example, using flow cytometry. Alternatively, or in addition, binding to a particular immune cell population may be assessed using flow cytometry, which may use, for example, one or more specific markers for a particular immune cell population, e.g., CD3, CD45, CD56, and CD159 (NKG2A) (for NK cells), CD14 (for monocytes), CD19 (for B cells), and / or CD4 / CD8 (for T cells).

[0201] Additionally, the effect of one or more CD38 modulating antibody agents (e.g., anti-CD38 antibodies or antigen-binding fragments thereof) described herein (e.g., comprising aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348 amino acid sequence (or variants thereof), or otherwise comprising the structural and / or functional characteristics of an agent described herein as a CD38 modulating antibody agent, such as CD38 modulating antibody agent-hIgG1) on human primary tumor cells and / or immune cells isolated from healthy human donors and / or patients may be evaluated. To investigate potential effects on individual immune cell populations in more detail, such CD38 modulating antibody agents can be used to treat PBMCs and / or cells isolated from tumors (and / or organs such as lymph nodes), and / or purified human CD8 and CD4 T cells, regulatory T cells, MDSC cells, dendritic cells, macrophages and monocytes, neutrophils, NK cells, and other cell types. Potential readouts include cytokine release, tumor cell killing, cell proliferation and / or activation, apoptosis, antigen-specific and / or allogeneic responses, or any combination thereof. Alternatively, or in addition, mice or non-human primates can be treated and cell status can be tracked using flow cytometry or after isolating various organs and / or cells from those animals.

[0202] Alternatively, or in addition, one or more properties of a CD38 modulating antibody agent (e.g., an anti-CD38 antibody or antigen-binding fragment thereof) described herein (e.g., comprising an aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348 amino acid sequence (or a variant thereof), or otherwise comprising the structural and / or functional properties of an agent described herein as a CD38 modulating antibody agent, such as CD38 modulating antibody agent-hIgG1) may be determined by the structural and / or functional properties of such a CD38 modulating antibody agent, such as the ability of such a CD38 modulating antibody agent to bind to CD38-expressing cells (e.g., NK cells or T cells), CD38 enzymatic activity, CD38-induced Ca2+ expression, or the like. 2+These processes may be assessed, alone or in combination, by studying the effects on levels and protein phosphorylation, CD38 shedding and / or internalization, CD38-induced activation of intracellular pathways (e.g., the NFκB pathway), and / or interactions with CD31 and other receptor proteins (e.g., CD16, TCR, BCR, etc.). The involvement of the latter processes in CD38 downstream activities may also be assessed using specific inhibitors of these processes.

[0203] To gain further insight into the molecular interactions between the provided CD38 modulating antibody drugs and human CD38, CD38 modulating antibody drugs (e.g., aCD38-a-323-h The crystal structure of IgG1 aCD38-a-306-hIgG1, aCD38-b-329-hIgG1, aCD38-a-327-hIgG1, or aCD38-b-348-hIgG1 antibodies) and human CD38 protein may be determined. The solubility and / or stability of the provided CD38 modulating antibody agents (specifically including, for example, aCD38-a-323-hIgG1, aCD38-a-306-hIgG1, aCD38-b-329-hIgG1, aCD38-a-327-hIgG1, or aCD38-b-348-hIgG1 antibodies) may be evaluated by solubility studies, accelerated stress studies, freeze-thaw studies, and formal stability studies. Antibody aggregation may be assessed by visual inspection, size exclusion chromatography, and dynamic light scattering and OD spectroscopy. 280 / 320 It can be followed by absorbance.

[0204] The present invention includes variants or derivatives of the antibodies disclosed herein, such as any of aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, and aCD38-b-348. Variants or derivatives of antibodies or antigen-binding fragments thereof (e.g., aCD38-b-329-m6, aCD38-b-329-m7, aCD38-b-348-m1, aCD38-b-348-m2, aCD38-b-348-m3, and aCD38-b-348-m4) may share the same functional profile (i.e., pharmacological properties) as the antibodies from which they are derived. Similarly, the invention includes antibodies or antigen-binding fragments that compete with any of the antibodies disclosed herein, e.g., aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, and aCD38-b-348 (or variants thereof) for binding to CD38. Such competing antibodies can have the same functional profile (i.e., pharmacological properties) as the antibodies they compete with for binding to CD38. [Brief description of the drawings]

[0205] [Figure 1]aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, and aCD38-b-348 are agonistic anti-CD38 antibodies according to the invention having one or more properties, in particular CD38 modulating antibody drug characteristics of particular interest: pharmacologic relevance target cell killing (e.g., as measured by ADCC, ADCP, and CDC assays), immune cell (Treg, CD8 and CD4) activity to measure properties such as cell survival and / or proliferation, cytokine secretion, and / or activation markers. 1 is a flow chart summarizing the screening procedures to identify those described herein that exhibit antibody sequences and formats, the presence and / or effect of glycosylation sites or free cysteines within the variable domains (e.g., in the human IgG1 frame as a Fab, nanobody, bi / multispecific antibody, or in a non-antibody scaffold) to identify stability issues related to effects on CD38 enzymatic activity or CD38-mediated signaling, effects on cancer cells expressing (or not expressing) CD38, combination with other drugs (e.g., antibodies targeting tumor antigens or other anti-cancer drugs), and / or sequences prone to aggregation. [Diagram 2] Related Protein Sequences, aCD38-a-323 Protein Sequence. Each CDR of the heavy chain (aCD38-a-323-HCDR1 (SEQ ID NO: 1), aCD38-a-323-HCDR2 (SEQ ID NO: 2), and aCD38-a-323-HCDR3 (SEQ ID NO: 3)) and light chain (aCD38-a-323-LCDR1 (SEQ ID NO: 5), aCD38-a-323-LCDR2 (SEQ ID NO: 6), and aCD38-a-323-LCDR3 (SEQ ID NO: 7)) within the frame sequences of the heavy and light chain antibodies initially identified by the screening procedure (aCD38-a-323-HCDR123 (SEQ ID NO: 4) and aCD38-a-323-LCDR123 (SEQ ID NO: 8), respectively) is shown separately and underlined. [Diagram 3]Characterization of aCD38-a-323 binding to CD38 expressed on PBMCs using either cynomolgus monkey-derived cells (A) or human-derived cells (B) at increasing antibody concentrations, restricting the analysis to CD8- or CD4-positive cells, and comparing with a human IgG1 isotype control. [Figure 4] Functional characterization of aCD38-a-323 compared to daratumumab (DARA) or negative control antibodies (anti-human CD3 or human IgG1 isotype) in cell-based models independent of administration of any additional tumor-targeting antibodies. (A) aCD38-a-323 increases the percentage of TCR-mediated CD4 and CD8 T cell proliferation as indicated in each graph. (aCD38-a-323 was tested at 10, 5, 2.5 μg / mL, hIgG1 and DARA were tested at 10 μg / mL, and the anti-CD3 concentration providing baseline activation is 0.1 μg / mL). (B) aCD38-a-323 increases secretion of GM-CSF by TCR-activated CD4 / CD8 T cells (similar pattern in 3 of 3 donors tested) (aCD38-a-323 tested at 10, 5, 2.5 μg / mL, hIgG1 and DARA tested at 10 μg / mL, anti-CD3 tested at 0.1 μg / mL). [Diagram 5] Functional characterization of aCD38-a-323 compared to DARA for cytotoxicity. (A) Both aCD38-a-323 and DARA induce killing of CD38-expressing Daudi cells by antibody-dependent cell-mediated cytotoxicity (ADCC). In addition, both aCD38-a-323 and daratumumab (DARA) induce complement-dependent cytotoxicity (CDC). (B) DARA induces CDC to a higher degree than aCD38-a-323, with aCD38-a-323 inducing only 40% cytolysis by CDC, whereas DARA induces over 90% cytolysis (CDC of DARA is particularly significant as described in the literature). [Figure 6]Functional characterization of aCD38-a-323 compared to Daratumumab (DARA) and control antibody (human IgG1 isotype) for enzymatic activity. Inhibition or activation of CD38 cyclase or NADase (hydrolase) activity in Daudi cells by aCD38-323 and control antibody is tested. (A) aCD38-a-323 increases cyclase activity compared to human IgG1 antibody, while DARA decreases cyclase activity (N=2 experiments). (B) aCD38-a-323 decreases NADase activity, while DARA does not decrease NADase activity (N=2 experiments). [Figure 7] Related Protein Sequences, aCD38-a-306 Protein Sequence. Each CDR of the heavy chain (aCD38-a-306-HCDR1 (SEQ ID NO: 9), aCD38-a-306-HCDR2 (SEQ ID NO: 10), and aCD38-a-306-HCDR3 (SEQ ID NO: 11)) and light chain (aCD38-a-306-LCDR1 (SEQ ID NO: 13), aCD38-a-306-LCDR2 (SEQ ID NO: 14), and aCD38-a-306-LCDR3 (SEQ ID NO: 15)) within the frame sequences of the heavy and light chain antibodies initially identified by the screening procedure (aCD38-a-306-HCDR123 (SEQ ID NO: 12) and aCD38-a-306-LCDR123 (SEQ ID NO: 16), respectively) is shown individually and underlined. [Figure 8] Characterization of aCD38-a-306 binding to CD38 expressed on PBMCs using either cynomolgus monkey-derived cells (A) or human-derived cells (B) at increasing antibody concentrations, restricting the analysis to CD8- or CD4-positive cells, and comparing with a human IgG1 isotype control. [Figure 9]Functional characterization of aCD38-a-306 compared to daratumumab (DARA) or negative control antibodies (anti-human CD3 or human IgG1 isotype) in cell-based models independent of administration of any additional tumor-targeting antibodies. (A) aCD38-a-306 increases the percentage of TCR-mediated CD8 and CD4 T cell proliferation as indicated in each graph. (Daratumumab tested at 10, 5, 2.5, 1.25 μg / mL, aCD38-a-306 and hIgG1 tested at 10 μg / mL, anti-CD3 tested at 0.5 μg / mL). (B) aCD38-a-306 does not increase secretion of selected cytokines by TCR-activated CD4 / CD8 T cells (similar pattern in 3 out of 3 donors tested). Antibodies were tested at the same concentrations. [Figure 10] Functional characterization of aCD38-a-306 compared to DARA for cytotoxicity. (A) Both aCD38-a-306 and DARA induce killing of CD38-expressing target cells by antibody-dependent cell-mediated cytotoxicity (ADCC). (B) Unlike DARA, aCD38-a-306 does not induce killing by complement-dependent cytotoxicity (CDC, where CDC of DARA is particularly significant as described in the literature). [Figure 11]Related Protein Sequences (A), aCD38-b-329 Protein Sequence. Each CDR of the heavy chain (aCD38-b-329-HCDR1 (SEQ ID NO: 17), aCD38-b-329-HCDR2 (SEQ ID NO: 18), and aCD38-b-329-HCDR3 (SEQ ID NO: 19)) and light chain (aCD38-b-329-LCDR1 (SEQ ID NO: 21), aCD38-b-329-LCDR2 (SEQ ID NO: 22), and aCD38-b-329-LCDR3 (SEQ ID NO: 23)) within the frame sequences of the heavy and light chain antibodies initially identified by the screening procedure (aCD38-b-329-HCDR123 (SEQ ID NO: 20) and aCD38-b-329-HCDR123 (SEQ ID NO: 24), respectively) is shown separately and underlined. The DG motif (double underlined) represents a hotspot for antibody isomerization and degradation (Sydow J et al. 2014) and can be mutated to provide alternative anti-CD38 antibodies with any and possibly all of the binding and functional properties of aCD38-b-329. (B) Sequence of human CD38 (Uniprot code P28907) (SEQ ID NO: 47) compared to one of the daratumumab epitopes (DARA, identified and disclosed in WO2006 / 099875, formed by two human CD38 regions, denoted herein as DARAep-a and DARAep-b), with different boxes identifying the location of the previously identified aCD38-b-329 major epitope (aCD38-b-ep) within the cytoplasmic, transmembrane, and extracellular domains. [Figure 12] Characterization of aCD38-b-329 binding to CD38 expressed on PBMCs by using human derived cells at increasing antibody concentrations, restricting the analysis to CD8 positive or CD4 positive cells, and comparing with either human IgG1 isotype control, daratumumab (DARA), or in the presence of primary antibody. [Figure 13]Functional characterization of aCD38-b-329 compared to Daratumumab (DARA) or negative control antibodies (anti-human CD3 or human IgG1 isotype) in cell-based models independent of administration of any additional tumor-targeting antibodies. (A) aCD38-b-329 increases the percentage of TCR-mediated CD4 and CD8 T cell proliferation as shown in each graph. (IgG1 and anti-CD38 antibodies are each tested at 10, 5, 2.5 μg / mL, anti-CD3 at 0.1 μg / mL). (B) aCD38-b-329 increases secretion of selected cytokines by TCR-activated CD4 / CD8 T cells (similar pattern in 5 out of 5 donors tested). [Figure 14] Functional characterization of aCD38-b-329 compared to DARA for cytotoxicity. (A) This direct antibody-mediated killing effect is accompanied by antibody-dependent cell-mediated cytotoxicity (ADCC) similar to daratumumab (DARA). The data also suggest that this antibody exhibits reduced complement-dependent cytotoxicity (CDC) compared to DARA. (B) Furthermore, target cell killing determined in Daudi cells is strongly induced by antibody cross-linking when aCD38-b-329 is compared to DARA, whose activity is not significantly increased by antibody cross-linking. [Figure 15] Functional characterization of aCD38-b-329 (administered at 10 mg / kg) on ​​animal survival in two cancer models based on intravenous administration of Daudi (A) and Ramos (B) cells over the indicated days. Treatment with aCD38-b-329 increases animal survival compared to negative controls. aCD38-b-329 also increases survival when compared to daratumumab (DARA) in the Daubi model. [Figure 16]Related Protein Sequences (A), aCD38-b-348 Protein Sequence. Each CDR of the heavy chain (aCD38-b-348-HCDR1 (SEQ ID NO: 25), aCD38-b-348-HCDR2 (SEQ ID NO: 26), and aCD38-b-348-HCDR3 (SEQ ID NO: 27)) and light chain (aCD38-b-348-LCDR1 (SEQ ID NO: 29), aCD38-b-348-LCDR2 (SEQ ID NO: 30), and aCD38-b-348-LCDR3 (SEQ ID NO: 31)) within the frame sequences of the heavy and light chain antibodies initially identified by the screening procedure (aCD38-b-348-HCDR123 (SEQ ID NO: 28) and aCD38-b-348-HCDR123 (SEQ ID NO: 32), respectively) is shown separately and underlined. The DG motif (double underlined) represents a hotspot for antibody isomerization and degradation (Sydow J et al. 2014) and can be mutated to provide alternative anti-CD38 antibodies with any and possibly all of the binding and functional properties of aCD38-b-348. (B) Sequence of human CD38 (Uniprot code P28907) (SEQ ID NO: 47) compared to one of the daratumumab epitopes (DARA identified and disclosed in WO2006 / 099875 formed by two human CD38 regions, designated herein as DARAep-a and DARAep-b), with different boxes identifying the location of the previously identified aCD38-b-348 major epitope (aCD38-b-ep) within the cytoplasmic, transmembrane, and extracellular domains. [Figure 17] Characterization of aCD38-b-348 binding to CD38 expressed on PBMCs using cynomolgus monkey-derived cells (A) or human-derived cells at increasing antibody concentrations, restricting the analysis to CD8- or CD4-positive cells, and comparing with either human IgG1 isotype control, daratumumab (DARA), or in the presence of primary antibody. [Figure 18]Functional characterization of aCD38-b-348 compared to Daratumumab (DARA) or negative control antibodies (anti-human CD3 or human IgG1 isotype) in cell-based models independent of administration of any additional tumor-targeting antibodies. (A) aCD38-b-348 increases the percentage of TCR-mediated CD4 and CD8 T cell proliferation as indicated in each graph. (IgG1 and anti-CD38 antibodies are each tested at 10, 5, 2.5 μg / mL, anti-CD3 at 0.1 μg / mL). (B) aCD38-b-348 increases NK proliferation and activation in PBMC-MDA-MB-231 cocultures (ratio 100:1). The percentage of proliferating CD56-positive, CD56-positive, and CD137-positive NK cells is indicated in each graph. (C) aCD38-b-348 increases secretion of selected cytokines by TCR-activated CD4 / CD8 T cells (similar patterns in 5 of 5 donors tested). [Figure 19] Functional characterization of aCD38-b-348 compared to DARA for cytotoxicity. (A) Both aCD38-b-348 and DARA induce regulatory T cell killing at 1 μg / mL and 10 μg / mL by inducing phagocytosis of CD38 positive regulatory T cells. (B) This direct antibody-mediated killing effect is accompanied by antibody-dependent cell-mediated cytotoxicity (ADCC) similar to daratumumab (DARA), but unlike DARA, it has lower complement-dependent cytotoxicity (CDC, where CDC of DARA is particularly significant as described in the literature). (C) Furthermore, target cell killing determined in Daudi cells is strongly induced by antibody cross-linking when aCD38-b-348 is compared to DARA, whose activity is not significantly increased by antibody cross-linking. [Figure 20] Functional characterization of aCD38-b-348 (administered at 10 mg / kg) on ​​animal survival in two cancer models based on intravenous administration of Daudi (A) and Ramos (B) cells for the indicated days. Treatment with aCD38-b-348 increases animal survival not only when compared to negative controls, but also when compared to daratumumab (DARA). [Figure 21]Related protein sequences (A), aCD38-a-327 protein sequence. Each CDR of the heavy chain (aCD38-a-327-HCDR1 (SEQ ID NO: 33), aCD38-a-327-HCDR2 (SEQ ID NO: 34), and aCD38-a-327-HCDR3 (SEQ ID NO: 35)) and light chain (aCD38-a-327-LCDR1 (SEQ ID NO: 37), aCD38-a-327-LCDR2 (SEQ ID NO: 38), and aCD38-a-327-LCDR3 (SEQ ID NO: 39)) within the frame sequences of the heavy and light chain antibodies initially identified by the screening procedure (aCD38-a-327-HCDR123 (SEQ ID NO: 36) and aCD38-a-327-LCDR123 (SEQ ID NO: 40), respectively) is shown separately and underlined. (B) The sequence of human CD38 (Uniprot code P28907) (SEQ ID NO: 47) compared to one of the daratumumab epitopes (DARA, identified and disclosed in WO2006 / 099875, formed by two human CD38 regions designated herein as DARAep-a and DARAep-b), with different boxes identifying the location of the previously identified aCD38-a-327 major epitope (aCD38ep-a and aCD38ep-b) within the cytoplasmic, transmembrane, and extracellular domains. [Figure 22] Characterization of aCD38-a-327 binding to CD38 expressed on human cell lines using CD38-expressing human lymphoma cell lines, Daudi cells and Raji cells, at increasing antibody concentrations and compared to a human IgG1 isotype control. [Diagram 23]Functional characterization of aCD38-a-327 compared to DARA for cytotoxicity. (A) Both aCD38-a-327 and DARA induce killing of CD38-expressing Daudi cells by antibody-dependent cell-mediated cytotoxicity (ADCC). (B) Furthermore, daratumumab (DARA) induces complement-dependent cytotoxicity (CDC), whereas aCD38-a-327 does not, with CDC of DARA being particularly significant, as described in the literature. (C) and (D) Furthermore, target cell killing determined in Daudi cells is not induced by antibody cross-linking when aCD38-a-327 is compared to DARA, whose activity is not significantly increased by antibody cross-linking. [Figure 24] Functional characterization of aCD38-a-327 compared to Daratumumab (DARA) and control antibody (human IgG1 isotype) for enzymatic activity. Inhibition or activation of CD38 cyclase or NADase (hydrolase) activity in Jurkat cells by aCD38-327 and control antibody is tested. (A) aCD38-a-327 moderately inhibits cyclase activity compared to human IgG1 antibody (about 20%), while DARA strongly reduces cyclase activity (about 70% inhibition) (N=2 experiments). (B) aCD38-a-327 does not interfere with NADase activity, while DARA increases NADase activity (about 30% increase) (N=2 experiments). [Diagram 25] Figure 1 shows the binding of anti-CD38 antibodies aCD38-b-348, aCD38-a-323, and aCD38-a-306, and aCD38-a-327 to His-tagged recombinant human CD38 compared to daratumumab as measured by biolayer interferometry on an Octet Red 96 instrument. 4.2 nM rhCD38-His, followed by 7 nM antibody, were loaded onto the Ni NTA biosensor, after which they were dissociated in kinetic buffer. [Figure 26]Functional characterization of aCD38-b-348, aCD38-a-323, and aCD38-a-306 compared to DARA for cytotoxicity. aCD38-b-348 exhibits ADCP activity as measured using the NFAT report assay in Jurkat cells. [Figure 27] Functional characterization of aCD38-b-348, aCD38-a-323, aCD38-a-306, and aCD38-a-327 compared to Daratumumab and human IgG1 isotype control for enzymatic activity. Inhibition or activation of CD38 cyclase or NADase (hydrolase) activity in Jurkat cells by aCD38-b-348, aCD38-a-323, aCD38-a-306, and aCD38-a-327, as well as control antibodies, is tested. (A) aCD38-a-323 induces cyclase activity compared to human IgG1 antibody, while aCD38-b-348 (p=0.34), aCD38-a-306 (p=0.07), aCD38-a-327 (p=0.12), and DARA decrease cyclase activity. Thus, while aCD38-a-306 shows a trend towards inhibition (p=0.07), the slight inhibition observed with aCD38-b-348 and aCD38-a-327 was not statistically significant. (B) aCD38-a-323 and aCD38-a-306 reduced NADase activity, while aCD38-b-348, aCD38-a-327, and DARA did not. The results for aCD38-a-327 in Figure 27 confirm those in Figure 24, which presents data from only one experiment (n=1). Figure 27 presents data as the average of three independent experiments (n=3). [Figure 28] Characterization of aCD38-b-348, aCD38-a-323, and aCD38-a-306 (administered at 10 mg / kg) for animal survival in in vivo solid tumor cancer models over the indicated days. Treatment with aCD38-b-348 and aCD38-a-306 increases animal survival not only when compared to negative controls, but also when compared to daratumumab (DARA). [Figure 29]Functional characterization of aCD38-b-348 compared to daratumumab (DARA) or negative control antibody (human IgG1 isotype) in an NFAT signaling luciferase reporter assay in Jurkat cells. The NFAT signaling of this antibody (measured as relative luminescence units (RLU)) is at least 30% higher than that of daratumumab when cells are stimulated with antibody concentrations of 10-20ug / mL and the RLU of CD3 only stimulation was used as the baseline for the assay (the RLU of the CD3 only condition was subtracted from the other conditions). [Diagram 30] Figure 30 shows the binding of anti-CD38 antibodies aCD38-a-323 (Figure 30A), aCD38-a-327 (Figure 30B), aCD38-a-306 (Figure 30C), aCD38-b-348 (Figure 30D), and aCD38-b-329 (Figure 30E) to His-tagged recombinant human CD38 compared to daratumumab (Figure 30F) as measured by biolayer interferometry on an Octet Red 96 instrument. 4.2 nM rhCD38-His was loaded onto the Ni-NTA biosensor followed by various concentrations of antibody (as indicated in the figure) and then they were dissociated in kinetic buffer. [Diagram 31] Figure 1 shows CDC of aCD38-b-348 and aCD38-a-327 compared to Dara and human IgG1 isotype control antibody on Raji cells at 10% complement. aCD38-b-348 exhibits reduced CDC compared to Dara and aCD38-a-327 exhibits no CDC. [Diagram 32] Low-dose anti-CD38 antibody aCD38-b-348 increases T cell activation in non-human primates. aCD38-b-348 was administered at a dose of 0.03 mg / kg to cynomolgus monkeys, and T cell activation was assessed. [Diagram 33]Relevant heavy and light chain protein sequences of variant aCD38-b-329 antibodies, A) aCD38-b-329-m6 and B) aCD38-b-329-m7. Each CDR of the heavy and light chain is underlined in the frame sequences of aCD38-b-329-m6-HCDR123 (SEQ ID NO: 20) and aCD38-b-329-m6-LCDR123 (SEQ ID NO: 62), respectively, and in the frame sequences of aCD38-b-329-m7-HCDR123 (SEQ ID NO: 20) and aCD38-b-329-m7-LCDR123 (SEQ ID NO: 63), respectively. [Diagram 34] Binding of variant sequences to Daudi cells compared to Dara and IgG1 controls. Binding to a CD38-expressing human cell line (Daudi) was tested by adding anti-CD38 primary antibody at 20 μg / mL followed by a half-log dilution series (7 points) and then staining with secondary antibody. The aCD38-b-329 variant shows similar binding to Daudi cells as the parent aCD38-b-329 and DARA. [Diagram 35] Functional characterization of aCD38-b-329 and its variant sequences compared to DARA for cytotoxicity. aCD38-b-329 and its variant sequences, as well as DARA, induced killing of a CD38+ cell line (Daudi) by antibody-dependent cell-mediated cytotoxicity (ADCC) with no detectable differences in activity (EC50 or maximum lysis). [Diagram 36]Relevant heavy and light chain protein sequences of variant aCD38-b-348 antibodies, A) aCD38-b-348-m1, B) aCD38-b-348-m2, C) aCD38-b-348-m3, and D) aCD38-b-348-m4. For aCD38-b-348-m1, aCD38-b-348-m1-HCDR123 (SEQ ID NO: 28) and aCD38-b-348-m1-LCDR123 (SEQ ID NO: 58), respectively; for aCD38-b-348-m2, aCD38-b-348-m2-HCDR123 (SEQ ID NO: 28) and aCD38-b-348-m2-LCDR123 (SEQ ID NO: 59), respectively; for aCD38-b-348-m3, In the case of aCD38-b-348-m4, the CDRs of the heavy and light chains are underlined in the frame sequences of aCD38-b-348-m3-HCDR123 (SEQ ID NO: 28) and aCD38-b-348-m3-LCDR123 (SEQ ID NO: 60), respectively, and in the case of aCD38-b-348-m4, the CDRs of the heavy and light chains are underlined in the frame sequences of aCD38-b-348-m4-HCDR123 (SEQ ID NO: 28) and aCD38-b-348-m4-LCDR123 (SEQ ID NO: 61), respectively. [Figure 37] Binding of variant sequences to Daudi cells compared to Dara and IgG1 controls. Binding to a CD38-expressing human cell line (Daudi) was tested by adding anti-CD38 primary antibody at 20 μg / mL followed by a half-log dilution series (7 points) and then staining with secondary antibody. The aCD38-b-348 variant shows similar binding to Daudi cells as the parent aCD38-b-348 and DARA. [Figure 38] Functional characterization of aCD38-b-348 and its variant sequences compared to DARA for cytotoxicity. aCD38-b-348 and its variant sequences, as well as DARA, induced killing of a CD38+ cell line (Daudi) by antibody-dependent cell-mediated cytotoxicity (ADCC) with no detectable differences in activity (EC50 or maximum lysis). [Figure 39]Functional characterization of aCD38-b-329 and variants aCD38-b-329-m6 and aCD38-b-329-m7 (all administered at 10 mg / kg), as well as aCD38-b-348 and its variants aCD38-b-348-m2, in terms of animal survival in two cancer models based on intravenous administration of Raji cells (A) and Ramos cells (B) over the indicated days. In both models, treatment with aCD38-b-329 and aCD38-b-348-m2 increases animal survival compared to negative controls. In both models, treatment with aCD38-b-348, as well as treatment with variants aCD38-b-329-m6 and a-CD38-b-329-m7 increases animal survival compared to negative controls and compared to daratumumab (DARA). [Diagram 40] Degranulation of non-activated or IL-2 pre-activated human NK cells by aCD38-b-348 compared with hIgG1 isotype, daratumumab, and control. [Diagram 41] NK cell IFNγ production in the presence or absence of tumor targets (MDA-MB-231 cells) with aCD38-b-348 compared with hIgG1 isotype and daratumumab. [Diagram 42] NK cell proliferation of human NK cells in the presence of MDA-MB-231 tumor cells by aCD38-b-348 compared to hIgG1 isotype and daratumumab. A) Antibodies were tested at 10 μg / mL. B) Dose titrations of antibodies from 0.4 μg / mL to 10 μg / mL were tested. [Diagram 43] SPR-based analysis of purified antibodies (IgG1) against His-tagged rhCD38 on a Biacore 2000. A) aCD38-a-323, B) aCD38-a-327, C) aCD38-b-348, D) aCD38-b-348-m1, E) aCD38-b-348-m2, F) aCD38-b-348m3, G) aCD38-b-348-m4, H) aCD38-a-306, I) aCD38-b-329, J) aCD38-b-329-m6, and K) aCD38-b-329-m7. [Diagram 44] Competition assay with aCD38-b-329, aCD38-b-348, aCD38-a-327, and daratumumab in Octet. Binding of the first antibody to immobilized rhCD38 is followed again by either the first antibody (as a control) or the second antibody. While non-competing antibodies bind to CD38 in the presence of other antibodies (Figure 43A, B, and C), antibodies binding to the same epitope will compete and no further binding will be observed (Figure D). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0206] Definitions, technical meanings, and embodiments of certain terms used herein are provided below, many or most of which confirm the common understanding of those of ordinary skill in the art.

[0207] Administration: As used herein, the term "administration" refers to the administration of a composition to a subject. Administration to an animal subject (e.g., a human) may be by any suitable route. For example, in some embodiments, administration may be bronchial (including bronchial instillation), buccal, enteral, intra-arterial, intradermal, intragastric, intramedullary, intramuscular, intranasal, intraperitoneal, intrathecal, intravenous, intraventricular, intraspecific organ or tissue (e.g., intrahepatic, intratumoral, peritumoral, etc.), mucosal, nasal, oral, rectal, subcutaneous, sublingual, topical, tracheal (including intratracheal instillation), transdermal, intravaginal, and intravitreal. Administration may include intermittent dosing. Alternatively, administration may include continuous dosing (e.g., perfusion) for at least a selected period of time. As known in the art, antibody therapy is generally administered parenterally, for example, by intravenous, subcutaneous, or intratumoral injection (e.g., particularly when a high intratumoral dose is desired).

[0208] Agent: As used herein, the term "agent" may refer to any chemical class of compound or entity, including, for example, polypeptides, nucleic acids, saccharides, small molecules, metals, or combinations thereof. Particular embodiments of agents that may be utilized in accordance with the present invention include small molecules, drugs, hormones, antibodies, antibody fragments, aptamers, nucleic acids (e.g., siRNA, shRNA, antisense oligonucleotides, ribozymes), peptides, peptidomimetics, and the like. An agent may be or include a polymer.

[0209] Antibody: As used herein, the term "antibody" refers to a polypeptide that contains sufficient standard immunoglobulin sequence elements to confer specific binding to a particular target antigen, such as CD38, human CD38, specifically extracellular human CD38. As known in the art, naturally produced intact antibodies are approximately 150 kD tetrameric agents composed of two identical heavy chain polypeptides (about 50 kD each) and two identical light chain polypeptides (about 25 kD each) that bind together in what is commonly referred to as a "Y-shaped" structure. Each heavy chain is composed of at least four domains, each about 110 amino acids long, an amino-terminal variable (VH) domain (located at the end of the Y structure), followed by three constant domains: CH1, CH2, and carboxy-terminal CH3 (located at the base of the stem of the Y). A short region known as the "switch" links the heavy chain variable region to the heavy chain constant region. A "hinge" links the CH2 and CH3 domains to the remainder of the antibody. Two disulfide bonds in this hinge region link the two heavy chain polypeptides together in an intact antibody. Each light chain is composed of two domains separated from each other by another "switch", an amino-terminal variable (VL) domain followed by a carboxy-terminal constant (CL) domain. An intact antibody tetramer is composed of two heavy-light chain dimers in which the heavy and light chains are linked together by a single disulfide bond, and two other disulfide bonds link the heavy chain hinge regions together, such that the dimers are linked together to form a tetramer. Naturally produced antibodies are typically glycosylated in the CH2 domain, and each domain has a structure characterized by an "immunoglobulin fold" formed from two beta sheets (e.g., three-, four-, or five-stranded sheets) packed together in a compressed antiparallel beta barrel. Each variable domain is composed of three hypervariable loops known as "complementarity determining regions" (e.g., as determined according to the Kabat numbering scheme, as understood in the art). The Fc region of a naturally occurring antibody comprises four CDRs (CDR1, CDR2, and CDR3) and four somewhat invariant "framework" regions (FR1, FR2, FR3, and FR4). When a natural antibody folds, the FR regions from the beta sheets that provide the structural framework for the domains and the CDR loop regions from both the heavy and light chains come together in three-dimensional space to create a single hypervariable antigen-binding site that is located at the end of a Y structure. The Fc region of a naturally occurring antibody binds to elements of the complement system and also to receptors on effector cells, including effector cells that mediate cytotoxicity. As known in the art, the affinity and / or other binding properties of the Fc region for the Fc receptor can be modulated by glycosylation or other modifications that can improve the exploitability of the antibody (Jarasch A et al., 2015).

[0210] In some embodiments, antibodies produced and / or utilized according to the invention comprise a glycosylated Fc domain, including Fc domains in which such glycosylation has been modified or engineered. For purposes of the present invention, in certain embodiments, any polypeptide or polypeptide complex that comprises a full immunoglobulin domain sequence found in a natural antibody may be referred to and / or used as an "antibody," regardless of whether such polypeptide is produced naturally (e.g., produced by an organism that responds to an antigen) or produced by recombinant engineering, chemical synthesis, or other artificial systems or methodologies. In some embodiments, the antibodies are polyclonal or oligoclonal, produced as a panel of antibodies, each binding to a single antibody sequence and binding to substantially distinct epitopes within the antigen (such as different epitopes within the human CD38 extracellular domain that are bound by different reference anti-CD38 antibodies).

[0211] Polyclonal or oligoclonal antibodies may be provided in a single preparation for medical use as described in the literature (Kearns JD et al., 2015). In some embodiments, the antibody is monoclonal. In some embodiments, the antibody has constant region sequences characteristic of mouse, rabbit, primate, or human antibodies. In some embodiments, the antibody sequence elements are humanized, primatized, chimeric, etc., as known in the art. Furthermore, the term "antibody" as used herein may, in appropriate embodiments (unless otherwise specified or clear from the context), refer to any of the constructs or formats known or developed in the art for utilizing the structural and functional characteristics of antibodies in alternative presentations, such as antigen-binding fragments defined below. For example, the antibodies utilized according to the present invention are of a type selected from, but not limited to, intact IgG, IgE, and IgM, bi- or multispecific antibodies (e.g., Zybodies®, etc.), single chain variable domains (scFv), polypeptide-Fc fusions, Fab, camelid antibodies, heavy chain shark antibodies (IgNAR), masked antibodies (e.g., Probodies®), or fusion proteins with polypeptides that allow expression and exposure at the cell surface (as scFv in constructs to obtain artificial T cell receptors used to transfer the specificity of monoclonal antibodies to T cells). Masked antibodies may include a blocking or "masking" peptide that specifically binds to the antigen-binding surface of the antibody and prevents antigen binding of the antibody. The masking peptide is linked to the antibody by a cleavable linker (e.g., by a protease). Selective cleavage of the linker under the desired environment, e.g., the tumor environment, allows dissociation of the masking / blocking peptide, allowing antigen binding in the tumor, thereby limiting potential toxicity issues. In some embodiments, the antibody may lack a covalent modification (e.g., attachment of a glycan) that it would have if produced naturally. Alternatively, the antibody may include a covalent modification (e.g., attachment of a glycan, a payload (e.g., a detectable moiety, a therapeutic moiety, a catalytic moiety, etc.), or other pendant group (e.g., polyethylene glycol, etc.).

[0212] Antigen: As used herein, the term "antigen" refers to an antigen that induces an immune response and / or It refers to an agent that binds to a T cell receptor (e.g., when presented by an MHC molecule) and / or a B cell receptor. Antigens that induce a humoral response, either accompanied by the production of antigen-specific antibodies, or as shown in the examples for the CD38 extracellular domain, can be used to screen antibody libraries and identify candidate antibody sequences that are further characterized.

[0213] Antigen-binding fragment: As used herein, the term "antigen-binding fragment" encompasses agents that include or comprise one or more portions of an antibody described herein sufficient to confer to the antigen-binding fragment the ability to specifically bind to the antigen targeted by the antibody. For example, in some embodiments, the term encompasses any polypeptide or polypeptide complex that contains sufficient immunoglobulin structural elements to confer specific binding. Exemplary antigen-binding fragments include, but are not limited to, small modular immunopharmaceuticals ("SMIPs™"), single chain antibodies, camelid antibodies, single domain antibodies (e.g., shark single domain antibodies), single chain or tandem diabodies (TandAbs®), VHHs, Anticalins®, Nanobodies®, Minibodies, BiTEs®, Ankyrin repeat proteins or DARPINs®, Avimers®, DARTs, TCR-like antibodies, Adnectins®, Affilins®, Trans-bodies®, Affibodies®, TrimerX®, MicroProteins, Centyrin®, CoVX bodies, bicyclic peptides, Kunitz domain-derived antibody constructs, or any other antibody fragments (so long as they exhibit the desired biological activity). In some embodiments, the term encompasses other protein structures, such as staple peptides, antibody-like binding peptidomimetics, antibody-like binding scaffold proteins, monobodies, and / or other non-antibody protein scaffolds, such as those reviewed in the literature (Vazquez-Lombardi R et al., 2015). In some embodiments, an antigen-binding fragment is or comprises a polypeptide whose amino acid sequence comprises one or more structural elements recognized by those skilled in the art as complementarity determining regions (CDRs).In some embodiments, an antigen-binding fragment is or comprises a polypeptide whose amino acid sequence comprises at least one reference CDR (e.g., at least one heavy chain CDR and / or at least one light chain CDR), specifically at least one heavy chain CDR, e.g., HCDR3 (e.g., aCD38-a-323-HCDR3 sequence, aCD38-a-306-HCDR3 sequence, aCD38-b-329-HCDR3 sequence, aCD38-a-327-HCDR3 sequence, or aCD38-b-348-HCDR3 sequence), substantially identical to that found in an anti-CD38 antibody described herein (e.g., an aCD38-a-323 amino acid sequence element, an aCD38-a-306 amino acid sequence element, an aCD38-b-329 amino acid sequence element, an aCD38-a-327 amino acid sequence element, or an aCD38-b-348 amino acid sequence element). In some embodiments, an antigen-binding fragment is, or comprises, a polypeptide that includes at least one CDR (e.g., at least one heavy chain CDR and / or at least one light chain CDR) whose amino acid sequence is either identical in sequence to such reference CDR or contains a small number (e.g., one, two, three, or four) amino acid modifications (e.g., substitutions, additions, or deletions, often substitutions) while maintaining binding to the target of the antibody from which the reference CDR is derived (e.g., aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348). In some embodiments, the antigen-binding fragment is or comprises a polypeptide or complex thereof that includes all three CDRs (or in some embodiments, sequences substantially identical thereto) from the heavy or light chain of the reference antibody (e.g., aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348). In some embodiments, the antigen-binding fragment is or comprises all six CDRs (or in some embodiments, sequences substantially identical thereto) from the reference antibody (e.g., aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348). In some embodiments, the antigen-binding fragment is or comprises a polypeptide or a complex thereof comprising a heavy and / or light chain variable domain (or in some embodiments, a sequence substantially identical thereto) of a reference antibody (e.g., aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348). In some embodiments, the term "antigen-binding fragment" encompasses non-peptide and non-protein structures, such as nucleic acid aptamers, e.g., RNA aptamers and DNA aptamers. Aptamers are oligonucleotides (e.g., DNA, RNA, or analogs or derivatives thereof) that bind to a specific target, such as a polypeptide. Aptamers are short synthetic single-stranded oligonucleotides that specifically bind to a variety of molecular targets, e.g., small molecules, proteins, nucleic acids, and even cells and tissues. These small nucleic acid molecules can form secondary and tertiary structures that can specifically bind to proteins or other cellular targets, and are essentially the chemical equivalent of antibodies. Aptamers are highly specific, relatively small in size, and non-immunogenic. Aptamers are generally selected from a biopanning method known as SELEX (Systematic Evolution of Ligands by Exponential enrichment) (see, e.g., Ellington et al. Nature. 1990;346(6287):818-822; Tuerk et al., Science. 1990;249(4968):505-510; Ni et al., Nature. 1990;249(4968):505-510). al., Curr Med Che 2011;18(27):4206-14). Methods for generating aptamers for any given target are well known in the art. Also included are peptide aptamers, including affimers. Affimers are small, highly stable proteins engineered to display peptide loops that provide a high affinity binding surface for a particular target protein. It is a low molecular weight (12-14 kDa) protein derived from the cystatin cysteine ​​protease inhibitor family. Affimer proteins consist of a stable protein scaffold based on the cystatin protein fold. They display two peptide loops and an N-terminal sequence that can be randomized to bind different target proteins with high affinity and specificity similar to antibodies. Stabilization of the peptides on a protein scaffold constrains the possible conformations that the peptides can adopt, thus increasing binding affinity and specificity compared to libraries of free peptides.

[0214] Percent sequence identity: The percent "sequence identity" between two sequences may be determined using methods known in the art. Sequence identity to a peptide, polypeptide, or antibody sequence may be defined as the percentage of amino acid residues in a candidate sequence that are identical to those in a particular peptide or polypeptide sequence, after aligning the sequences and introducing gaps, if necessary, to achieve the maximum percent sequence identity, without considering any conservative substitutions as part of the sequence identity. Alignment for purposes of determining percent amino acid sequence identity may be performed in a variety of ways within the skill of the art, for example, using publicly available computer software, such as BLAST, BLAST-2 (including gapped BLAST), and BLASTp (for proteins) (Altschul SF, et al (1997)), or FASTA using default parameters.

[0215] Biological sample. As used herein, the term "biological sample" or "sample" typically refers to a sample obtained or derived from a biological source of interest (e.g., a tissue or organism or cell culture) as described herein. The source of interest may be an organism, such as an animal or a human. The biological sample may include biological tissue or biological fluid.

[0216] Cancer: "cancer," "malignant tumor," "neoplasm," "tumor," "tumor" "mour" and "carcinoma" are used interchangeably herein to refer to cells that exhibit relatively abnormal, uncontrolled, and / or autonomous growth such that they exhibit an abnormal growth phenotype characterized by a marked lack of control of cell proliferation. Generally, cells of interest for detection or treatment in this application include precancerous (e.g., benign), malignant, premetastatic, metastatic, and nonmetastatic cells. The teachings of the present disclosure may relate to any and all cancers. To name just a few non-limiting examples, in some embodiments, the teachings of the present disclosure apply to one or more cancers, such as hematopoietic cancers (including leukemia, lymphoma (Hodgkin's and non-Hodgkin's), myeloma, and myeloproliferative syndromes), sarcoma, melanoma, adenoma, solid tissue cancer, oral, throat, larynx, and lung squamous cell carcinoma, liver cancer, genitourinary cancers, such as prostate cancer, cervical cancer, bladder cancer, uterine cancer, and endometrial cancer, as well as renal cell carcinoma, bone cancer, pancreatic cancer, skin cancer, cutaneous or intraocular melanoma, endocrine system cancer, thyroid cancer, parathyroid cancer, head and neck cancer, breast cancer, gastrointestinal cancer, and nervous system cancer, benign lesions, such as papilloma, and the like.

[0217] The antibodies of the invention may be used to treat CD38+ expressing tumors.

[0218] CD38 Modulating Antibody Agents. The term "CD38 modulating antibody agent" is used herein to refer to a CD38 modulating antibody agent (e.g., an anti-CD38 antibody) that exhibits certain properties described herein. In many embodiments, desirable CD38 modulating antibody agents described herein are characterized in that they stimulate immune effector cells and / or modify immune cell function, are cytotoxic to CD38 expressing cells, such as immunosuppressive cells or tumor cells (e.g., in either case expressing CD38 on their surface), or induce phagocytosis of CD38 expressing cells (e.g., expressing high levels of CD38). In some embodiments, the CD38 modulating antibody agent is characterized by an activity (e.g., level and / or type) on immune cells (e.g., when contacted with immune cells, specifically immune cells expressing CD38) and on tumor cells that is substantially equivalent to the activity of aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348. In some embodiments, the relevant activity is or includes ADCP, ADCC in the absence of CDC, direct killing, depletion of certain CD38 expressing cells (e.g., high expressing cells), activation of effector immune cells, promotion of T cell, B cell, or NK cell proliferation, modulation of immune cell activity (e.g., repolarization of suppressive macrophages to inflammatory macrophages), skewing of the T cell repertoire, and the like, and combinations thereof. In some embodiments, the CD38 modulating antibody agent is an entity or moiety whose presence or level correlates with CD38 levels and / or activity and / or correlates with one or more characteristics or results characteristic of CD38 activity. In some embodiments, the increase in level and / or activity is assessed or determined relative to that observed under otherwise equivalent conditions in the absence of the entity(ies) or moiety(ies). Alternatively, or in addition, in some embodiments, the increase in level and / or activity is comparable to or exceeds that observed under equivalent conditions in the presence of a reference CD38 modulating antibody agent (e.g., a suitable reference anti-CD38 antibody, which in many embodiments is a CD38 agonist antibody such as IB4).In many embodiments, a CD38 modulating antibody agent for use according to the present disclosure is or comprises an entity or moiety that binds directly or indirectly to CD38, typically to its extracellular domain. In some embodiments, a CD38 modulating antibody agent is, comprises, or competes with an anti-CD38 antibody exemplified herein, an antigen-binding fragment thereof (e.g., including one or more CDRs, all heavy chain CDRs, all light chain CDRs, all CDRs, heavy chain variable region, light chain variable region, or both heavy and light chain variable regions), an affinity matured variant thereof (or an antigen-binding fragment thereof), or any alternative form of any of the foregoing (e.g., chimeric, humanized, multispecific, alternative isotype, etc.). Alternatively, or in addition, in some embodiments, a CD38 modulating antibody agent as described herein is an antibody that has been screened, manufactured, (pre)clinical tested, and / or characterized for relevant epitopes within human CD38, as disclosed herein. The compound may be characterized by one or more features that may be advantageous in certain cases and / or in a particular context for formulation, administration, and / or efficacy (e.g., for cancer therapy).

[0219] Combination therapy: As used herein, the term "combination therapy" refers to a situation in which a subject is exposed to two or more treatment regimens (e.g., two or more therapeutic agents) simultaneously. In some embodiments, two or more agents may be administered simultaneously. Alternatively, such agents may be administered sequentially or, alternatively, such agents are administered in overlapping dosing regimens.

[0220] Equivalent: As used herein, the term "equivalent" refers to two or more agents, entities, situations, effects, sets of conditions that may not be identical to each other, but are similar enough to allow a comparison between them (e.g., by level and / or type of activity) so that a valid conclusion can be made based on observed differences or similarities. Such equivalent sets of conditions, effects, situations, individuals, or populations are characterized by a number of substantially identical characteristics and one or a few diverse characteristics. Those skilled in the art will understand from the context what degree of identity is required in any given situation for two or more such agents, entities, situations, sets of conditions, effects, or populations, etc. to be considered equivalent.

[0221] Comprising: A composition or method described herein as "comprising" one or more named elements or steps is open-ended, meaning that the element or step is required, but that other elements or steps may be added within the scope of the composition or method. It is also understood that any composition or method described as "comprising" one or more named elements or steps also describes a corresponding more limited composition or method that "consistes essentially of" (or "consists essentially of") the same named elements or steps, meaning that the composition or method includes the named essential elements or steps, and may also include additional elements or steps that do not materially affect the basic and novel property(s) of the composition or method.

[0222] Daratumumab: As used herein, the term "daratumumab" includes antibodies having the VH and VL sequences published in WO2006 / 099875 and which are human IgG1 monoclonal antibodies, e.g., having variable heavy and light chain sequences comprising the respective sequences provided below. Heavy Chain: JPEG2025028972000030.jpg35170 Light chain JPEG2025028972000031.jpg21170

[0223] Dosage form: As used herein, the term "dosage form" refers to a physically discrete unit of an active agent (e.g., a therapeutic or diagnostic agent) for administration to a subject. Each unit contains a predetermined amount of the active agent. In some embodiments, such an amount is sufficient to produce a desired effect when administered to a relevant population. A unit dosage (or a whole fraction thereof) appropriate for administration according to a dosing regimen (i.e., a therapeutic dosing regimen) determined to correlate with a desired or beneficial outcome. One of ordinary skill in the art will understand that the total amount of therapeutic composition or therapeutic agent administered to a particular subject will be determined by one or more attending physicians and may involve administration of multiple dosage forms.

[0224] Dosing regimen: As used herein, the term "dosing regimen" refers to a set of unit doses (typically two or more) administered individually to a subject, typically separated by time. In some embodiments, a given therapeutic agent has a recommended dosing regimen that may include one or more doses. In some embodiments, a dosing regimen includes multiple doses, each separated from each other by the same amount of time. Alternatively, a dosing regimen includes multiple doses and at least two different times separating the individual doses. In some embodiments, all doses within a dosing regimen are of the same unit dose amount. Alternatively, different doses within a dosing regimen are of different amounts. In some embodiments, a dosing regimen includes a first dose in a first dose amount, followed by one or more additional doses in a second dose amount that is different from the amount of the first dose. A dosing regimen may include a first dose in a first dose amount, followed by one or more additional doses in a second dose amount that is the same as the amount of the first dose. In some embodiments, the dosing regimen correlates with a desired or beneficial outcome when administered across a relevant population (ie, is a therapeutic dosing regimen).

[0225] Epitope: As used herein, the term "epitope" refers to a portion of an antigen that is bound by an antibody or antigen-binding fragment. In some embodiments, when the antigen is a polypeptide, an epitope is conformational in that it is made up of portions of the antigen that are not covalently adjacent in the antigen, but are close to each other in three-dimensional space when the antigen is in the relevant conformation. For example, in the case of CD38, a conformational epitope is one that is made up of amino acid residues that are not adjacent in the CD38 extracellular domain, and a linear epitope is one that is made up of amino acid residues that are adjacent in the CD38 extracellular domain. In some embodiments, epitopes utilized in accordance with the present invention are provided with reference to those bound by the CD38 modulating antibody agents provided herein (e.g., by aCD38-a-323, by aCD38-a-306, by aCD38-a-327 defined as aCD38ep-a and aCD38ep-b, by aCD38-b-329 defined as aCD38-b-ep, or by aCD38-b-348 defined as aCD38-b-ep). Means for determining the exact sequence and / or particularly the amino acid residues of the epitope of aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348 are known in the literature and in the Examples, including competition with peptides derived from the antigen sequence, binding to CD38 sequences from different species, truncation, and / or mutagenesis (e.g., by alanine scanning or other site-directed mutagenesis), phage display-based screening, or (co-)crystallography techniques.

[0226] Patient: As used herein, the term "patient" or "subject" refers to any organism to which a provided composition is or can be administered, e.g., for experimental, diagnostic, preventative, cosmetic, and / or therapeutic purposes. Typical patients include animals (e.g., mammals such as mice, rats, rabbits, non-human primates, and / or humans). In some embodiments, the patient is human. In some embodiments, the patient is suffering from or susceptible to one or more disorders or conditions. The patient may exhibit one or more symptoms of a disorder or condition or may have been diagnosed with one or more disorders or conditions (such as cancer, or the presence of one or more tumors). In some embodiments, the patient is undergoing or has undergone a certain therapy to diagnose and / or treat such disease, disorder, or condition.

[0227] Pharmaceutically acceptable: As used herein, the term "pharmacologically acceptable" applied to a carrier, diluent, or excipient used to formulate a composition disclosed herein means that the carrier, diluent, or excipient must be compatible with the other ingredients of the composition and not deleterious to the recipient thereof.

[0228] Pharmaceutical composition: As used herein, the term "pharmaceutical composition" refers to a composition in which an active agent is formulated together with one or more pharma- ceutically acceptable carriers. In some embodiments, the active agent is present in an amount of unit dose suitable for administration in a treatment regimen that exhibits a statistically significant probability of achieving a predetermined therapeutic effect when administered to a relevant population. Pharmaceutical compositions can be formulated in solid or liquid form for administration, including oral administration, e.g., drenches (aqueous or non-aqueous solutions or suspensions), tablets, e.g., buccal, sublingual, and those targeted for systemic absorption, boluses, powders, granules, pastes for application to the tongue, parenteral administration, e.g., subcutaneous, intramuscular, intravenous, intratumoral, or epidural injection as a sterile solution or suspension, or sustained release formulations, topical application (e.g., as a cream, ointment, or controlled release patch or spray applied to the skin, lung, or buccal cavity), vaginal, rectal, sublingual, ocular, transdermal, nasal, pulmonary, and other mucosal surfaces.

[0229] Solid Tumor: As used herein, the term "solid tumor" refers to an abnormal mass of tissue that usually does not contain cysts or liquid areas. Solid tumors can be benign or malignant. Different types of solid tumors are named after the type of cell they originate from. Examples of solid tumors are sarcoma (including cancers derived from transformed cells of mesenchymal origin in tissues such as cancellous bone, cartilage, fat, muscle, blood vessels, hematopoietic, or fibrous connective tissue), carcinoma (including tumors derived from epithelial cells), melanoma, lymphoma, mesothelioma, neuroblastoma, retinoblastoma, etc. Cancers that include solid tumors include, but are not limited to, brain cancer, lung cancer, stomach cancer, duodenal cancer, esophageal cancer, breast cancer, colorectal cancer, kidney cancer, bladder cancer, kidney cancer, pancreatic cancer, prostate cancer, ovarian cancer, melanoma, oral cancer, sarcoma, eye cancer, thyroid cancer, urethral cancer, vaginal cancer, cervical cancer, lymphoma, etc.

[0230] Therapeutically effective amount: As used herein, the term "therapeutically effective amount" refers to an amount (e.g., an amount of a drug or pharmaceutical composition) sufficient to treat a disease and / or condition when administered to a population suffering from or susceptible to the disease and / or condition according to a therapeutic dosing regimen. A therapeutically effective amount is one that reduces the incidence and / or severity of, stabilizes, and / or delays the onset of one or more symptoms of a disease, disorder, and / or condition. Those skilled in the art will understand that a "therapeutically effective amount" does not actually require successful treatment to be achieved in a particular subject.

[0231] Treatment: As used herein, the term "treatment" (also "treat" or "treating") refers to any administration of a substance (e.g., a provided CD38 modulating antibody agent, exemplified by aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348, or any other agent) that partially or completely alleviates, improves, relieves, suppresses, delays the onset of, reduces the severity of, and / or reduces the incidence of one or more symptoms. In some embodiments, treatment includes direct administration of a CD38 modulating antibody agent, such as aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348 (e.g., as an injectable aqueous composition, optionally including pharma- ceutically acceptable carriers, excipients, and / or adjuvants, for intravenous, intratumoral, or peritumoral injection), or by obtaining cells from a subject (e.g., from blood, tissue, or tumor, with or without selection based on the presence or absence of expression of a marker), contacting such cells ex vivo with a CD38 modulating antibody agent, such as aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, or aCD38-b-348, and administering such cells to the subject (based on the presence or absence of expression of a marker). The present invention may include administration using a regimen that includes administering the present invention to a subject using the method of the present invention (with or without selection based on absence).

[0232] Dosage and Administration. Pharmaceutical compositions comprising the CD38 modulating antibody agents described herein (e.g., anti-CD38 or antigen-binding fragments thereof, including, e.g., aCD38-a-323-HCDR3, aCD38-a-306-HCDR3, aCD38-b-329-HCDR3, aCD38-a-327-HCDR3, or aCD38-b-348-HCDR3 amino acid sequences) for use according to the invention can be prepared for storage and / or delivery using any of a variety of techniques and / or technologies known and / or available to those of skill in the art. In some embodiments, the provided CD38 modulating antibody agents are administered according to a dosing regime approved by a regulatory authority, such as, for example, the U.S. Food and Drug Administration (FDA) and / or the European Medicines Agency (EMEA), for the relevant indication. In some embodiments, the provided CD38 modulating antibody agents are administered in combination with one or more other agents or therapies, which may themselves be administered according to a dosing regimen approved by a regulatory agency, such as the U.S. Food and Drug Administration (FDA) and / or the European Medicines Agency (EMEA), for example, for a relevant indication. However, in some embodiments, the use of the provided CD38 modulating antibody agents may allow for reduced dosing (e.g., one or more doses of a smaller amount, fewer dosings, and / or less frequent dosing) of the approved agent or therapy used in combination with the CD38 modulating antibody agent therapy. In some embodiments, dosing and / or administration may be adapted to other drugs, patient conditions, and / or the format of the CD38 modulating antibody agent (e.g., modified as an immunoconjugate, single domain antibody, or bispecific antibody) that are also administered.

[0233] Additionally, in some embodiments, it may be desirable to tailor dosing regimens, and in particular design sequential dosing regimens, based on timing and / or threshold expression levels of CD38, whether for a particular cell type, a particular tumor or type thereof, or a particular patient population (e.g., a patient population with a genetic marker). In some such embodiments, therapeutic dosing regimens may be combined with or tailored to account for detection methods that evaluate expression of one or more inducible markers or other criteria prior to and / or during therapy.

[0234] In some embodiments, dosing and administration according to the present invention utilizes an active agent having a desired purity combined with one or more physiologically acceptable carriers, excipients, or stabilizers in any or a variety of forms. These include, for example, liquid, semi-solid and solid dosage forms, such as liquid solutions (e.g., injectable and infusible solutions), dispersions or suspensions, tablets, pills, powders, liposomes, and suppositories. The preferred form may depend on the intended method of administration and / or therapeutic application, typically in the form of injectable and infusible solutions, such as compositions similar to those used to treat human subjects with antibodies.

[0235] In some embodiments, the component(s) may be prepared with a carrier that protects the agent(s) from rapid release and / or degradation, such as controlled release formulations, including implants, transdermal patches, and microencapsulated delivery systems. Biodegradable biocompatible polymers, such as polyanhydrides, polyglycolic acids, polyorthoesters, and polylactic acids, may be used. In general, each active agent is formulated, dosed, and administered in a therapeutically effective amount using pharmaceutical compositions and dosing regimens consistent with good medical practice and appropriate for the relevant agent(s) (e.g., agents such as antibodies). Pharmaceutical compositions containing active agents may be administered by any suitable method known in the art, including, but not limited to, oral, mucosal, inhalation, topical, buccal, nasal, rectal, or parenteral (e.g., intravenous, infusion, intratumoral, intranodal, subcutaneous, intraperitoneal, intramuscular, intradermal, transdermal, or other types of administration, including physical breaching of a subject's tissue and administering the pharmaceutical composition through such breach).

[0236] In some embodiments, the dosing regimen for a particular active agent may include intermittent or continuous (e.g., by perfusion or sustained release system) administration, for example, to achieve a particular desired pharmacokinetic profile or other exposure pattern in one or more tissues or body fluids of interest in a subject. In some embodiments, different agents administered in combination may be administered by different delivery routes and / or according to different schedules. Alternatively, or in addition, in some embodiments, one or more doses of a first active agent are administered substantially simultaneously with one or more other active agents, in some embodiments by a common route and / or as part of a single composition.

[0237] Factors to be considered in optimizing the route and / or dosing schedule of a given treatment regimen may include, for example, the particular cancer being treated (e.g., type, stage, location, etc.), the clinical condition of the subject (e.g., age, general health, weight, etc.), the site of delivery of the agent, the nature of the agent (e.g., an antibody or other protein-based compound), the method and / or route of administration of the agent, the presence or absence of concomitant therapy, and other factors known to physicians.

[0238] Those skilled in the art will appreciate that, for example, a particular delivery route may affect the dose and / or the required dose may affect the delivery route. For example, focused delivery (e.g., intratumoral delivery) may be desirable and / or useful when a particularly high concentration of the agent is targeted within a particular site or location (e.g., within a tissue or organ). In some embodiments, one or more characteristics of a particular pharmaceutical composition and / or the dosing regimen utilized may be altered over time (e.g., increasing or decreasing the amount of activity in any individual dose, increasing or decreasing the time interval between doses, etc.), for example, to optimize a desired therapeutic effect or response (e.g., a therapeutic or biological response related to the functional characteristics of the CD38 modulating antibody agent described herein). In general, the type, amount, and frequency of dosing of an active agent according to the present invention are governed by the safety and efficacy requirements that apply when the relevant agent(s) are administered to a mammal, preferably a human. In general, such characteristics of dosing are selected to provide a specific, typically detectable, therapeutic response compared to that observed without the therapy. In the context of the present invention, exemplary desirable therapeutic responses may include, but are not limited to, inhibition and / or reduction of tumor growth, one or more of tumor size, metastasis, tumor-related symptoms and side effects, as well as increased apoptosis of cancer cells, therapeutically related reduction or increase of one or more cell markers or circulating markers, etc. Such criteria can be easily evaluated by any of a variety of immunological, cytological, and other methods disclosed in the literature. For example, a therapeutically effective amount of a CD38-modulating antibody agent, alone or in combination with additional agents, can be determined to be sufficient to enhance the killing of cancer cells as described in the examples.

[0239] A therapeutically effective amount of a CD38 modulatory antibody agent, either as an active agent or a composition comprising such an agent, can be readily determined using techniques available in the art that take into account one or more factors, including, for example, the disease or condition being treated, the stage of the disease, the age and health and physical condition of the mammal being treated, the severity of the disease, the particular compound being administered, and the like.

[0240] In some embodiments, a therapeutically effective amount is an effective dose (and / or unit dose) of an active agent that may be at least about 0.01 mg / kg body weight, at least about 0.05 mg / kg body weight, at least about 0.1 mg / kg body weight, at least about 1 mg / kg body weight, at least about 5 mg / kg body weight, at least about 10 mg / kg body weight, or more (e.g., 0.01, 0.1, 0.3, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, or 50 mg / kg body weight). One of skill in the art will appreciate that in some embodiments, such guidelines may be adjusted for the molecular weight of the active agent. Dosage may also vary depending on the route of administration, treatment cycle, or dose escalation protocols that may be used to determine the maximum tolerated dose and dose-limiting toxicity, if any, associated with administration of an isolated antibody or antigen-binding fragment thereof comprising the aCD38-a-323-HCDR3, aCD38-a-306-HCDR3, aCD38-b-329-HCDR3, aCD38-a-327-HCDR3, or aCD38-b-348-HCDR3 amino acid sequence resulting in increased doses.

[0241] Therapeutic compositions must typically be sterile and stable under the conditions of manufacture and storage. The compositions may be formulated as solutions, microemulsions, dispersions, liposomes, or other ordered structures suitable for high drug concentration. Sterile injectable solutions may be prepared by incorporating the antibody in the required amount in a suitable solvent with one or a combination of the ingredients listed above, followed by filtration sterilization. In general, dispersions are prepared by incorporating the active compound into a sterile vehicle that contains a basic dispersion medium and other required ingredients from those listed above. In the case of powders for preparing sterile injectable solutions, the preferred preparation methods are vacuum drying and freeze-drying, which result in a powder of the active ingredient and any additional desired ingredients from a previously sterile-filtered solution. The proper fluidity of the solution may be maintained, for example, by using coatings, by maintaining the required particle size in the case of dispersions, and by using surfactants. Prolonged absorption of the injectable compositions may be achieved by including an agent that delays absorption in the composition, for example, monostearate salts and gelatin.

[0242] The formulation of each agent should desirably be sterile, as can be accomplished by filtration through a sterile filtration membrane, and then packaged or sold in a form suitable for bolus or continuous administration. Injectable formulations can be prepared, packaged, or sold in unit dosage forms, such as ampoules or multi-dose containers containing a preservative. Formulations for parenteral administration include, but are not limited to, suspensions, solutions, emulsions, pastes, and implantable sustained-release or biodegradable formulations in oily or aqueous vehicles discussed herein. Sterile injectable formulations can be prepared using non-toxic parenterally acceptable diluents or solvents, such as water or 1,3 butanediol. Other useful parenterally administrable formulations include those that contain the active ingredient in microcrystalline form, in a liposomal preparation, or as a component of a biodegradable polymer system. Compositions for sustained release or implantation can include pharma-ceutically acceptable polymers or hydrophobic materials, such as emulsions, ion exchange resins, poorly soluble polymers, or salts.

[0243] Each pharmaceutical composition for use according to the invention may contain pharma- ceutically acceptable dispersing agents, wetting agents, suspending agents, isotonicity agents, coatings, antibacterial and antifungal agents, carriers, excipients, salts, or stabilizers that are non-toxic to subjects at the dosages and concentrations employed. A non-exhaustive list of such additional pharma- ceutically acceptable compounds includes buffers, such as phosphate, citric acid, and other organic acids; antioxidants, such as ascorbic acid and methionine; salts containing pharmacologically acceptable anions (e.g., acetate, benzoate, bicarbonate, bisulfate, isothioate, lactate, lactobionate, laurate, malate, maleate, salicylate, stearate, subacetate, succinate, tannate, tartrate, theoclate, tosylate, triethiodide, and valerate); preservatives (e.g., octadecyldimethylbenzyl ammonium chloride, hexamethonium chloride; benzalkonium chloride, benzethonium chloride; sodium chloride; phenol, butyl, or benzyl alcohol; alkyl parabens, such as methyl or propyl paraben; catechol; resorcinol; cyclohexanol; 3-pentanol; and m-cresol; low molecular weight (less than about 10 residues) polypeptides; proteins, such as serum albumin; hydrophilic polymers, such as polyvinylpyrrolidone; amino acids, such as glycine, glutamine, asparagine, glutamic acid, histidine, arginine, or lysine; monosaccharides, disaccharides, and other carbohydrates. hydrates, such as glucose, mannose, or dextrin; chelating agents, such as EDTA; sugars, such as sucrose, mannitol, trehalose, or sorbitol; salt-forming counterions, such as sodium; metal complexes (e.g., Zn-protein complexes); and / or non-ionic surfactants, such as TWEEN™, PLURONICS™, or polyethylene glycol (PEG).

[0244] In some embodiments, when two or more active agents are utilized according to the present invention, such agents can be administered simultaneously or sequentially.In some embodiments, the administration of one agent is specifically timed with respect to the administration of another agent.In some embodiments, the desired relative dosing regimen for the agents administered in combination can be evaluated or empirically determined, for example, using ex vivo, in vivo, and / or in vitro models, and in some embodiments, such evaluation or empirical determination is performed in vivo in a particular patient or patient population (e.g., to correlate).

[0245] In some embodiments, one or more active agents utilized in the practice of the present invention are administered according to an intermittent dosing regimen comprising at least two cycles. When two or more agents are administered in combination and each is administered by such an intermittent cycle regimen, the individual doses of the different agents may be combined with each other. In some embodiments, one or more doses of the second agent are administered after a dose of the CD38 modulating antibody agent described herein. In some embodiments, each dose of the second agent is administered after a dose of the CD38 modulating antibody agent described herein. In some embodiments, the CD38 modulating antibody agent described herein may be administered in a regimen that includes alternating routes of administration, such as subcutaneous (or intramuscular) and intratumoral administration, with such cycles being repeated in the same regimen (or by extending the interval between administrations) within one or more treatment cycles over a period of one, two, four weeks, or more, depending on the patient's response. Also, in some embodiments, the exact regimen followed (e.g., number of doses, spacing of doses (e.g., relative to each other or to another event, such as administration of another therapy), amount of dose, etc.) may be different in one or more cycles as compared to one or more other cycles.

[0246] Using any of the administration routes, dosages, and / or regimens described herein, the CD38 modulating antibody agents described herein can be identified, characterized, and / or validated in view of one or more criteria measured in patients using, for example, biopsies, blood samples, and / or other clinical criteria. In some embodiments, as an alternative to or in addition to direct assessment of tumor size and / or metastasis, the therapeutic efficacy of a CD38 modulating antibody agent described herein may be determined in a manner that assesses one or more of the following different general criteria (e.g., increase in activation or other phenotypic markers on immune cells, or measurement of cytokines and chemokines): direct cytotoxicity against cancer cells (cancer cell apoptosis and necrosis), increase in tumor infiltrating immune cells (such as CD4 positive and / or CD8 positive tumor infiltrating T cells), increase in immune cells circulating in the blood (total population or specific subpopulations of lymphocytes, NK cells, monocytes, dendritic cells, macrophages, B cells, etc.), and / or display of some differential expression (as determined by RNA sequencing, mass flow cytometry, and / or other mass sequencing approaches) comparing pre-treatment to post-treatment in either responding or non-responding patients only. Alternatively, or in addition, in some embodiments, such identification, characterization, and / or validation may include following up at the molecular level by screening the mRNA and / or protein expression of one or more specific proteins or one or more sets of proteins. In some embodiments, one or more such techniques may enable identification of or relevant information for assessing the response to a CD38 modulating antibody agent described herein, which may relate, for example, to tissue distribution and / or markers of specific cell populations within (or near) the tumor and / or circulating in the blood.

[0247] Such approaches and immunobiological data may not only allow for the determination of one or more efficacy and / or safety parameters or characteristics, but may in some embodiments provide a rationale for the selection of a particular dose, route, or dosing regimen that may be utilized alone and / or in combination with other drugs, standard treatment protocols, or immunotherapies that may provide additional therapeutic benefit, for example, in one or more clinical trials for a given indication. Thus, in a further set of embodiments of the invention, the CD38 modulating antibody agents described herein are used in methods of treating a patient suffering from a disease (such as cancer) or methods of preventing a disease (such as cancer) after determining the combined presence (and / or absence) of expression at the RNA and / or protein level of one or more genes in the patient's cells or tissues (such as tumors, blood samples, or blood fractions) after or before treatment with such agents. Such methods may thus enable the identification of one or more biomarkers, or more complex gene expression signatures (or cell population distributions) associated with a desirable therapeutically effective dose of a CD38 modulating antibody drug, therapeutically relevant biomarker(s) that predict that a subject will have an anti-tumor or anti-infective response following treatment with a CD38 modulating antibody drug described herein, or therapeutically relevant biomarker(s) that predict that a subject will respond to treatment with a compound following treatment with a CD38 modulating antibody drug.

[0248] Alternatively, or in addition, in some embodiments, dosing and administration of a particular CD38 modulating antibody agent disclosed herein may be pre-established and / or subsequently evaluated in light of CD38 expression in human cancers and / or other human tissues (e.g., by collecting data on CD38 distribution in stroma and / or immune subsets in various cancers, tissues, and / or patients). Such data may be generated by using common techniques (such as flow cytometry, mass cytometry, immunohistochemistry, or mRNA expression libraries) to identify the relationship of CD38 expression in various immune and non-immune subpopulations and / or its relationship to cellular infiltrate measures and / or cancer-associated markers associated with cancer cells or subsets of immune cells (such as Foxp3 and PD-1 / PD-L1) across common cancer types and / or tissues (central nervous system, esophagus, stomach, liver, colon, rectum, lung, bladder, heart, kidney, thyroid, pancreas, uterus, skin, breast, ovary, prostate, and testis). CD38 expression may (or may not) be restricted to immune subsets in tumor tissue (such as NK cells and other effector or regulatory immune cells) and, if positive, a correlation between CD38 expression and immune checkpoint inhibitors may be determined, thus suggesting appropriate use of CD38 modulating antibody agents in combination with compounds targeting such immune checkpoint inhibitors.

[0249] Articles of Manufacture and Kits. In some embodiments of the invention, the CD38 modulating antibody agent described herein is provided in a separate article of manufacture. In some embodiments of the invention, the article of manufacture comprising the CD38 modulating antibody agent is provided in or with a container having a label. Suitable containers may include, for example, bottles, vials, syringes, and test tubes. In some embodiments, the container may be formed from any or a variety of materials, such as glass or plastic. In some embodiments, the container holds a composition effective for treating a particular disease, disorder, or condition, or a stage or type thereof. In some embodiments, the container may have a sterile access port (e.g., the container may be an intravenous solution bag or vial having a stopper pierceable by a hypodermic needle). For example, in some embodiments, the composition comprising the CD38 modulating antibody agent described herein is packaged in a clear glass vial with a rubber stopper and an aluminum seal. The label on or associated with the container indicates that the composition is used for treating the condition of choice.

[0250] In some embodiments, the product is a solution of phosphate buffered saline, Ringer's solution, and dextran. It may further include a separate container containing a pharma- ceutically acceptable buffer, such as Strohs' solution, and / or may further include other materials desirable from a commercial and user standpoint, such as other buffers, diluents, fillers, needles, syringes, and a package insert with instructions for use. For example, in some embodiments, the product may provide for the provision of each of the drugs in an intravenous formulation containing a total of 2 mg, 5 mg, 10 mg, 20 mg, 50 mg, or more, as a sterile aqueous solution, formulated with appropriate diluents and buffers, at final concentrations of 0.1 mg / mL, 1 mg / mL, 10 mg / mL, or higher.

[0251] In some embodiments, the CD38 modulating antibody agent described herein may be provided in a kit of parts in lyophilized form to be reconstituted with any suitable aqueous solution provided with the kit or not provided with the kit, or in other types of dispensing devices using any compatible pharmaceutical carrier. One or more unit dosage forms of the CD38 modulating antibody agent may be provided in a pack or dispenser device. Such a pack or device may, for example, comprise a metal or plastic foil, for example a blister pack. For the correct use of such a kit of parts, it may further comprise buffers, diluents, fillers, needles, syringes, and package inserts with instructions for use in the treatment of cancer.

[0252] In some embodiments, instructions associated with an article of manufacture or kit described herein may be in the form of a label, pamphlet, publication, recording, diagram, or any other means that may be used to inform on the correct usage and / or monitor the possible effects of the drugs, formulations, and other materials in the article and / or kit. The instructions may be provided with the article of manufacture and / or may be provided within the kit. EXAMPLES

[0253] Example 1: Generation of antibodies that bind to CD38 in vitro material and method Preparation of CD38 antigen. Recombinant histidine-tagged extracellular domains of human, cynomolgus monkey (Cyno), and mouse CD38 proteins were purchased from Sino Biological Inc. Biotinylation of protein reagents was performed using EZ-Link Sulfo-NHS-Biotinylation Kit (Thermo Scientific, Cat. No. 21425). CD38 antigen was concentrated to approximately 1 mg / mL and buffer exchanged into PBS, followed by addition of biotinylation reagent (EZ-Link Sulfo-NHS-Biotinylation Kit, Thermo Scientific, Cat. No. 21425) at a 1:7.5 molar ratio. The mixture was kept at 4°C overnight and then exchanged into another buffer to remove free biotin in the solution. Biotinylation was confirmed by streptavidin sensor binding of the labeled protein.

[0254] Library matching of anti-CD38 antibodies and selection methodology for isolating anti-CD38 antibodies. Eight naive human synthetic yeast libraries, each with a diversity of approximately 109, were designed, generated, and grown for high-throughput screening and selection of yeast cell lines expressing monoclonal antibodies as previously described (Xu Y et al., 2013, WO2009 / 036379, WO2010 / 105256, WO20120 / 09568). Eight parallel selections were performed using the eight naive libraries for monomeric human CD38-based selections.

[0255] For the first two selection rounds, a magnetic bead sorting technique utilizing the Miltenyi MACs system was performed essentially as described (Siegel et al., 2004). Briefly, yeast cells (approximately 10 10 Cells / library) were incubated with 3 mL of 100 nM biotinylated monomeric human CD38 antigen in FACS wash buffer PBS containing 0.1% BSA for 15 min at room temperature. Washed once with 50 mL of ice-cold wash buffer. Afterwards, the cell pellet was resuspended in 40 mL of wash buffer and 500 μL of Streptavidin MicroBeads (Miltenyi Biotec, Germany, Cat. No. 130-048-101) were added to the yeast cells and incubated at 4° C. for 15 min. The yeast cells were then pelleted, resuspended in 5 mL of wash buffer and loaded onto a MACS LS column (Miltenyi Biotec, Germany, Cat. No. 130-042-401). After loading 5 mL, the column was washed three times with 3 mL of FACS wash buffer. The column was removed from the magnetic field and the yeast cells were eluted with 5 mL of growth medium and then grown overnight.

[0256] After two MACS rounds, five rounds of selection were performed using flow cytometry (FACS). For the first FACS selection round, approximately 4×10 7Yeast cells were pelleted, washed three times with wash buffer, and incubated with 100 nM each of biotinylated monomeric human, mouse, and cynomolgus CD38 antigens at room temperature for 10 min. Yeast cells were then washed twice and stained with goat anti-human F(ab')2 kappa-FITC (diluted 1:100) (Southern Biotech, USA, Cat. No. 2062-02) and either streptavidin Alexa Fluor 633 (Life Technologies, USA, Cat. No. S21375) (diluted 1:500) or Extravidin-phycoerythrin (Sigma-Aldrich, USA, Cat. No. E4011) (diluted 1:50) as secondary reagents for 15 min at 4°C. After washing twice with ice-cold wash buffer, cell pellets were resuspended in 0.4 mL of wash buffer and transferred to sorting tubes capped with strainers. Sorting was performed using a FACS ARIA sorter (BD Biosciences) to determine the sorting gate to select only CD38 binding. The mouse and cynomolgus monkey selected populations from the first FACS round were combined into two pools. These pools were then sorted for human CD38 binding to identify cross-reactive binders in the second FACS round to reduce reagent multispecific binders (Xu Y et al., 2013). The fourth FACS round consisted primarily of positive selection using 100 nM biotinylated monomeric CD38 as antigen. Samples of selected clones were plated and sequenced.

[0257] Affinity maturation of clones identified in naive selection. Heavy chains from the fourth FACS sorting selection round output were used to prepare a light chain diversified library that was used for four further selection rounds. The first selection round contained Miltenyi MACs beads conjugated with either 100 nM biotinylated monomeric human CD38 as antigen or 200 nM biotinylated monomeric mouse CD38 as antigen. After MACs bead selection, three FACS sorting rounds were performed. The first FACS round contained either 100 nM or 10 nM human CD38 or 200 nM mouse CD38. In parallel with the second FACS round described above, a competitive selection was performed with 75-100 nM competing IgG. After the selection rounds, a third positive selection was performed with 1 nM or 10 nM human CD38 before plating. Individual colonies from each FACS selection round were picked for IgG sequencing.

[0258] Production and purification of IgG and Fab. Yeast clones were grown to saturation and then induced for 48 hours at 30°C with shaking. After induction, yeast cells were pelleted and the supernatant was collected for purification. IgG was purified using a protein A column and eluted with acetic acid (pH 2.0). Fab fragments were generated by papain digestion and purified with CaptureSelect IgG-CH1 affinity matrix (Life Technologies, Cat. No. 1943200250).

[0259] Production of defucosylated aCD38 human IgG1 antibody expressed in mammalian cells: The codon-optimized VH and VL coding sequences of the antibodies were synthesized, and the cDNAs of the variable regions were The antibodies are cloned into antibody expression vectors (Evitria, Switzerland) using conventional (non-PCR-based) cloning techniques. The cDNA of the oxidoreductase, GDP-6-deoxy-d-lyxo-4-hexulose reductase (RMD) enzyme, is cloned into an expression vector (Evitria, Switzerland). Plasmid DNA is prepared under low endotoxin conditions based on anion exchange chromatography. Evitria uses suspension adapted CHO K1 cells (originally received from ATCC and adapted at Evitria for serum-free growth in suspension cultures) for production. Seeds are grown in eviGrow medium (chemically defined, animal component-free, serum-free medium). Cells are transfected with expression vectors for IgG1 and the RMD enzyme using eviFect (Evitria's custom proprietary transfection reagent). After transfection, cells are grown in eviMake2 (animal component-free, serum-free medium). The supernatant is collected by centrifugation and then by filtration (0.2 μm filter). The antibody is purified using MabSelect™ SuRe™. The glycosylation pattern of the antibody is characterized using LC / MS, showing >99% defucosylation.

[0260] Affinity measurement of anti-CD38 antibodies. The affinity of CD38 antibodies was determined by Forte Bio using their K DThe affinity of the IgG was determined by measuring the binding affinity of the IgG to the SA sensor. Forte Bio affinity measurements were performed by loading IgG onto the AHQ sensor online as described (Estep P et al., 2013). Briefly, the sensor was equilibrated offline for 30 min in assay buffer and then monitored online for 60 s for baseline establishment. For avidity measurements, IgG-loaded sensors were exposed to 200 nM human, cynomolgus monkey, or mouse CD38 for 3 min, after which they were transferred to assay buffer for 3 min for off-rate measurements. Monovalent binding measurements were obtained by loading biotinylated CD38 monomer onto the SA sensor and then exposing it to 200 nM Fab. Kinetic data were fitted using a 1:1 binding model in the data analysis software provided by Forte Bio. The Kd values ​​established in this assay for the reference agonist anti-CD38 antibodies are as follows: for IB4, 0.9 × 10 for human CD38, 0.9 × 10 for IgG4, 0.9 × 10 for IgG5, 0.9 × 10 for IgG6, 0.9 × 10 for IgG7, 0.9 × 10 for IgG8, 0.9 × 10 for IgG9, 0.9 × 10 for IgG1, 0.9 × 10 for IgG1, 0.9 × 10 for IgG2, 0.9 × 10 for IgG5, 0.9 × 10 for IgG1, 0.9 × 10 for IgG1, 0.9 × 10 for IgG2, 0.9 × 10 for IgG3, 0.9 × 10 for IgG4, 0.9 × 10 for IgG5, 0.9 × 10 for IgG1, 0.9 × 10 for IgG1, 0.9 × 10 for IgG1, 0.9 × 10 for IgG2, -8 M and IB4 do not bind to cynomolgus monkey CD38.

[0261] Binding force measurements of anti-CD38 antibodies: Ni-NTA sensors were equilibrated offline in assay buffer for 30 min and then monitored online for 60 s for baseline establishment. They were loaded with 4.2 nM of antigen (HIS-tagged recombinant human CD38) for 50 min, after which they were transferred to assay buffer for 0.5 min for washing and placed in assay buffer again for 1 min for baseline determination. Antibodies were then bound at different concentrations (listed in Figure 25 and Figure 30) for 30-50 min. They were then transferred to assay buffer for 20-30 min for off-rate measurements. The kinetic data were fitted using a 1:1 binding model in the data analysis software provided by ForteBio.

[0262] Alternatively, the affinity of anti-human CD38 antibodies was determined by measuring their K DThe binding affinity was determined by measuring the binding affinity of the antibody. Anti-human antibodies were first immobilized across all flow cells in analysis buffer (pH 7.4, 10 mM HEPES, 150 mM NaCl, 3 mM EDTA, 0.05% Tween 20) to 12,000-14,000 RU over 10 min. Ligand (antibody test substance) was then loaded to capture levels of 54-208 RU. Analyte (His-tagged recombinant human CD38) was then bound for 6 min in two-fold diluted analysis buffer starting at 3200 nM to a minimum concentration of 0.78 nM. Dissociation was performed in analysis buffer for 10 min. Regeneration steps between sample concentrations were performed three times over 0.5 min in 3 M MgCl2. A flow rate of 25 μL / min was maintained throughout this process. Reaction The rate data were fitted using global fitting in the analysis software provided by Biacore with baseline subtraction.

[0263] Epitope binning: Epitope binning of antibodies can be performed on a Forte Bio Octet Red384 system (Pall Forte Bio Corp., USA) using a standard sandwich binning assay. Anti-human CD38 antibodies can be loaded onto an AHQ sensor and unoccupied Fc binding sites on the sensor can be blocked with an unrelated human IgG1 antibody. The sensor can be exposed to 100 nM of target antigen followed by a second anti-CD38 antibody, a reference monoclonal agonist mouse anti-human CD38 antibody (IB4). Data can be processed using Forte Bio Data Analysis Software 7.0. Further binding by the second antibody after antigen association indicates an unoccupied epitope, while no binding indicates epitope blocking.

[0264] Binding of anti-CD38 antibodies to CD38-expressing cells. Candidate hits are evaluated by analyzing binding to purified cynomolgus T cells. For this purpose, cynomolgus pan-T cells were stained with 20 μg / mL followed by semi-log serial dilutions (7 points) of aCD38-a-323, aCD38-a-306, aCD38-b-348, or isotype control for 30 min on ice.

[0265] Unbound primary antibodies were removed by washing, followed by staining with secondary antibodies (5 μg / mL) for 30 min on ice. All samples were triplicate stained with appropriate CD3, CD4, and CD8 cross-reactive antibodies. Samples were measured by flow cytometry. For data analysis, live cells were gated using FSC vs. SSC parameters during sample acquisition. The mean fluorescence intensity (MFI) of stained cells was plotted on an XY chart graphing MFI against the logarithm of concentration, and data was fitted to a nonlinear regression curve from which EC50 was calculated.

[0266] Alternatively, binding was evaluated in human PBMCs. For this purpose, PBMCs were prepared from whole blood from three human donors and incubated for 30 min with aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-b-348, aCD38-a-327, DARA, or isotype control at final concentrations of 1 μM, 200 nM, 40 nM, 8 nM, 1.6 nM, 320 pM, 64 pM, 13 pM, and 2.5 pM. Cells were then washed and labeled with AF488 secondary antibody. Cells were then incubated with additional surface staining antibodies: anti-CD3 PE-Cy7, anti-CD4 APC, and anti-CD8 BV451. Sample acquisition was performed using an 8-color (3-laser) BD FACSCanto II cytometer running on BD FACSDiva software (BD Biosciences). Post-analysis processing was performed using FCS Expression (v3.0) software (DeNovo Software). Relative percentages (%) of different cell populations and mean fluorescence intensity (MFI) data were reported to two decimal places.

[0267] Recloning, production, and characterization of aCD38-a-323, aCD38-a-306, aCD38-b-329, aCD38-a-327, and aCD38-b-348 as human IgG1 expressed in mammalian cells. Synthesis of the codon-optimized VH and VL coding sequences of the antibodies was performed by Genewiz. The cDNAs of the variable regions were cloned into an antibody expression vector (Icosagen, EST) containing human IgG1 heavy and kappa light chain constant regions (P01857 and P01834, respectively). The full-length heavy and light chain cDNAs were verified by sequencing in the final vector and then recloned for their expression using QMCF Technology (Icosagen), a stable episomal expression system using CHO-based cells (CHOEBNALT85), and the vectors suitable for production of recombinant proteins, antibodies, CHOEBNALT85 cells, For antibody production, cells were transfected with 1 μg of expression plasmid. After 48 hours of transfection, 700 μg / mL G418 was added to select for the plasmid-containing cell population. For production, the temperature was shifted to 30° C. and the culture was further fed. At the end of production, the culture supernatant was purified by centrifugation (1000 g, 30 min, and 15° C.), PMSF was added, and the supernatant was processed or frozen until purification. hIgG1 antibodies were purified by MabSelect SuRe affinity chromatography followed by Superdex 200 gel filtration in either PBS containing 25 mM NaOAc (pH 5.5), 50 mM NaCl, or PBS containing 100 nM L-arginine. Human IgG1 antibodies produced in CHOEBNALT85 cells were characterized for affinity to recombinant human CD38, cross-reactivity to mouse, rat, rabbit, and cynomolgus CD38 using recombinant rabbit CD38 (65003-T08H-20, Sino Biological) and recombinant rat CD38: (80229-R08H-20, Sino Biological).

[0268] aCD38-b-348 epitope mapping. A different set of linear single loop, β-turn mimetic, disulfide bridge mimetic, discontinuous disulfide bridge, discontinuous epitope mimetic peptides representing the human CD38 sequence (Uniprot accession number P28907) were synthesized using solid-phase Fmoc synthesis (Pepscan BV, The Netherlands, Timmermann P et al., 2007; Langedijk JP et al., 2011). Antibody binding to each of the synthesized peptides was tested with a Pepscan-based ELISA (Pepscan, The Netherlands). Peptide arrays were incubated with the primary antibody solution (overnight at 4°C). After washing, peptide arrays were incubated with a 1 / 1000 dilution of the appropriate antibody-peroxidase conjugate (2010-05, Southern Biotech) for 1 h at 25°C. After washing, the peroxidase substrate 2,2'-azino-di-3-ethylbenzthiazoline sulfonate (ABTS) and 20 μL / mL of 3 percent H2O2 were added. After 1 h, the color development was measured. The color development was quantified with a charge-coupled device (CCD) camera and an image processing system. Values ​​obtained from the CCD camera ranged from 0 to 3000 mAU, similar to a standard 96-well plate ELISA reader. To demonstrate the quality of the synthesized peptides, a separate set of positive and negative control peptides were synthesized in parallel and screened with an unrelated control antibody.

[0269] Alanine scanning was performed to confirm the epitope. Alanine scanning was performed using Integral Molecular's epitope mapping platform based on shotgun mutagenesis to further characterize the epitope of the mAb. The coding region of the full-length CD38 protein was successfully codon-optimized, synthesized, and subcloned into a mammalian high expression vector. The parental construct was then sequence verified and validated for mammalian cell expression by immunodetection. Binding and screening conditions for aCD38-b-348 (mAb and Fab) using high-throughput flow cytometry were optimized using wild-type CD38 cloned into a proprietary vector and expressed in HEK-293T cells.

[0270] To map the epitopes of the antibodies, an alanine scanning library of CD38 was constructed. Antibodies (mAb and Fab) were then screened for binding to each individual CD38 variant, allowing identification of CD38 contact residues important for test mAb binding.

[0271] aCD38-b-329 epitope mapping. A different set of linear single loop, β-turn mimetic, disulfide bridge mimetic, discontinuous disulfide bridge, discontinuous epitope mimetic peptides representing the human CD38 sequence (Uniprot accession no. P28907) were bound to solid-phase Fm Peptides were synthesized using oc synthesis (Pepscan BV, The Netherlands, Timmermann P et al., 2007; Langedijk JP et al., 2011). Antibody binding to each of the synthesized peptides was tested with a Pepscan-based ELISA (Pepscan, The Netherlands). Peptide arrays were incubated (overnight at 4°C) with the primary antibody solution. After washing, peptide arrays were incubated for 1 h at 25°C with a 1 / 1000 dilution of the appropriate antibody-peroxidase conjugate (2010-05, Southern Biotech). After washing, the peroxidase substrate 2,2'-azino-di-3-ethylbenzthiazoline sulfonate (ABTS) and 20 μL / mL of 3 percent H2O2 were added. After 1 h, the color development was measured. The color development was quantified with a charge-coupled device (CCD) camera and an image processing system. Values ​​obtained from the CCD camera range from 0 to 3000 mAU, similar to a standard 96-well plate ELISA reader. To demonstrate the quality of the synthesized peptides, a separate set of positive and negative control peptides were synthesized in parallel and screened with an unrelated control antibody.

[0272] aCD38-a-327 epitope mapping. A different set of linear single loop, β-turn mimetic, disulfide bridge mimetic, discontinuous disulfide bridge, discontinuous epitope mimetic peptides representing the human CD38 sequence (Uniprot accession number P28907) were synthesized using solid-phase Fmoc synthesis (Pepscan BV, The Netherlands, Timmermann P et al., 2007; Langedijk JP et al., 2011). Binding of the a-327 antibody to each of the synthesized peptides was tested by ELISA (Pepscan, The Netherlands). The peptide arrays were incubated with the primary antibody solution (overnight at 4°C). After washing, the peptide arrays were incubated with a 1 / 1000 dilution of the appropriate antibody-peroxidase conjugate (2010-05, Southern Biotech) for 1 h at 25°C. After washing, the peroxidase substrate 2,2'-azino-di-3-ethylbenzthiazoline sulfonate (ABTS) and 20 μL / mL of 3 percent H2O2 were added. After 1 hour, color development was measured. Color development was quantified with a charge-coupled device (CCD) camera and an image processing system. Values ​​obtained from the CCD camera ranged from 0 to 3000 mAU, similar to a standard 96-well plate ELISA reader. To demonstrate the quality of the synthesized peptides, a separate set of positive and negative control peptides were synthesized in parallel and screened with an unrelated control antibody. Alanine scanning was performed by Integral Molecular as described above to confirm the epitope.

[0273] Anti-human CD38 antibody competition assay: Antibody competition was performed on a Forte Bio Octet Red96 system (Pall Forte Bio Corp., USA) using a standard sequential binding assay. 0.625ug / mL of His-tagged recombinant human CD38 was loaded onto a Ni-NTA biosensor for 300 seconds. After a 15 second wash and a baseline step with kinetic buffer for 60 seconds, the sensor was exposed to 66.6nM of the first antibody for 600 seconds, followed by the second anti-CD38 antibody (also at 66.6nM for 600 seconds). Data was processed using Forte Bio Data Analysis Software 9.0. Further binding by the second antibody indicates an unoccupied epitope (no competition at the epitope), while no binding indicates epitope blocking (competition at the epitope).

[0274] result Monoclonal antibodies (mAbs) that bind to recombinant human CD38 extracellular protein sequence (rhCD38) were isolated using a yeast-based antibody display library as described in Materials and Methods. These antibodies were sequenced and unique clones were produced in yeast cells (Barnard GC et al., 2010). Each yeast clone expressing a unique antibody sequence Cell culture supernatants were screened for rhCD38 binding.

[0275] KD values ​​(affinity and avidity measurements) and cross-binning analysis of selected antibodies are provided in Table 1. [Table 1A]

[0276] The binding of anti-CD38 antibodies to recombinant monovalent human CD38 as measured by Octet and compared to Daratumumab is shown in Figure 25 and Figure 30. The binding affinity of anti-CD38 antibodies (IgG1) to recombinant monovalent human CD38 was also measured by Biacore (believed to generate more reliable data). The results are shown in Table 1A and Figure 42.

[0277] The results of epitope mapping and alanine scanning confirmation are shown in Table 1B. [Table 1B]

[0278] A panel of mAbs was selected based on their binding to rhCD38, sequence specificity, and expression levels. These antibodies were further characterized for binding to recombinant cynomolgus monkey and mouse CD38 extracellular domain protein sequences. In addition, epitope binning was performed to determine whether antibodies aCD38-b-329 and aCD38-b-348 bind to epitopes that overlap with the epitope of the reference agonist anti-CD38 antibody IB4 (Ausiello CM et al., 2000, Ferrero E et al., 2004). -8 M~10 -10 The antibodies were characterized as exhibiting IgG binding values ​​against monovalent rhCD38 and / or recombinant cynomolgus CD38 extracellular protein sequences consisting of M. In addition, the antibodies were characterized as competing or non-competing with the reference agonist anti-CD38 antibody IB4 or the commercially available Daratumumab, DARA). All selected antibodies belong to different cross-binning groups as shown in Table 1. The antibody clones were evaluated at the binding level to human cells strongly expressing CD38, such as lymphoblastoid Raji cells, by flow cytometry, using CHO-S cells as a negative control. Furthermore, aCD38-a-323 was confirmed to bind to human PBMCs (Figure 3B), but not to cynomolgus pan T cells (Figure 3A). aCD38-a-306 was confirmed to bind to human CD4 and CD8 T cells (Figure 8B), but not to cynomolgus T cells (Figure 8A). Binding of aCD38-b-329 to human PBMCs (Figure 12) was confirmed. Binding of aCD38-b-348 to cynomolgus pan T cells (Figure 17A) and human PBMCs (Figure 17B) was confirmed.

[0279] Finally, to eliminate antibody sequences prone to aggregation and non-specific interactions, antibodies were screened with a multispecificity reagent (PSR) assay and affinity capture self-interaction nanoparticle spectroscopy (AC-SINS), an approach that allows high-throughput screening for early-stage antibody development (Liu Y et al., 2014). None of the selected antibodies scored positive in the latter assay and were therefore not eliminated from the panel.

[0280] Among the selected hits sequenced and characterized as described above, clone aCD38-a-323 presented novel complementarity determining regions (CDRs, FIG. 2) and was found to have a 10 -8 M~10 -11 It is an antibody that binds to the human CD38 extracellular protein sequence with a Kd value in the range of M. Alanine scanning showed that aCD38-a-323 binds to amino acid residues 12, 121, 141, and 241 (SEQ ID NO: 47) of human CD38, or at least these residues are required for antibody binding.

[0281] Thus, the aCD38-a-323 sequence (Figure 2) identifies antibodies that specifically bind to CD38 and their agonist activity can be functionally assessed by cell-based assays or animal models in relation to the functional characteristics that define CD38 modulating antibody agents as that term is used herein.

[0282] Clone aCD38-a-306 displays novel complementarity determining regions (CDRs, FIG. 7) and has 10 -8 M~10 -11 This antibody binds to the human CD38 extracellular protein sequence with a Kd value in the range of M.

[0283] Thus, the aCD38-a-306 sequence (Figure 7A) identifies antibodies that specifically bind to CD38 and their agonist activity can be functionally assessed by cell-based assays or animal models in relation to the functional characteristics that define CD38 modulating antibody agents as that term is used herein.

[0284] Clone aCD38-b-329 is an antibody that displays novel complementarity determining regions (CDRs, FIG. 11A) that do not compete with IB4 or daratumumab for human CD38 binding. Indeed, epitope mapping studies performed using Pepscan technology revealed that aCD 38-b-329 binds to human CD38 in a region distinct from that published for daratumumab (two beta strands including amino acids 233-246 and 267-280, FIG. 11B) or reported for other anti-human CD38 antibodies (see Table 2 in WO2015 / 123687), and -9 It would be shown that daratumumab binds to the human CD38 extracellular protein sequence with Kd values ​​in the range of M. Antibody competition assays showed that daratumumab does not compete with aCD38-b-329 for the same epitope (Figure 44B), however, the assays showed that aCD38-b-329 and aCD38-b-348 compete with each other for the same epitope (Figure 44D).

[0285] Thus, the aCD38-b-329 sequence (Figure 11A) identifies antibodies that specifically bind to CD38 and their agonistic activity, related to the functional characteristics that define CD38-modulating antibody drugs as that term is used herein, can be functionally evaluated by cell-based assays or animal models. Analysis of aCD38-b-329-LCDR3 shows the presence of a DG (Asp-Gly) motif, which represents a potential target for modifications during production that may affect some of the antibody properties. To this extent, aCD38-b-329-based antibody libraries in which either one or both residues were substituted, and among all such mutants, only a limited number of mutants (e.g., those expressed on the surface of Daudi cells) maintained binding to human CD38 (see Example 2). Thus, the corresponding aCD38-b-329-based antibody variants can be tested as either maintaining all the properties of a CD38-modulating antibody drug or simply having CD38 binding properties. Further validation of these variants can proceed using the assays disclosed in the Examples.

[0286] Clone aCD38-b-348 is an antibody that presents novel complementarity determining regions (CDRs, Figure 16A) that do not compete with either IB4 or daratumumab for human CD38 binding. Indeed, epitope mapping studies performed using Pepscan technology have demonstrated that aCD38-b-348 binds to human CD38 in a region that is distinct from those published for daratumumab (two beta strands including amino acids 233-246 and 267-280, Figure 16B) or those reported for other anti-human CD38 antibodies (see Table 2 in WO2015 / 123687) and that is 10 -9 M~10 -10It will be shown that aCD38-b-348 binds to human and cynomolgus CD38 extracellular protein sequences with Kd values ​​in the range of M. Alanine scanning confirms that the epitope region of aCD38-b-348, specifically its amino acid residue 78 of human CD38, is involved in binding. Antibody competition assays showed that daratumumab does not compete with aCD38-b-348 for the same epitope (Figure 44A), but the assays showed that aCD38-b-329 and aCD38-b-348 compete with each other for the same epitope (Figure 44D).

[0287] Thus, the aCD38-b-348 sequence (Figure 16A) identifies antibodies that specifically bind to CD38 and their agonistic activity, related to the functional characteristics that define CD38-modulating antibody drugs as that term is used herein, can be functionally evaluated by cell-based assays or animal models. Analysis of aCD38-b-348-LCDR3 shows the presence of a DG (Asp-Gly) motif, which represents a potential target for modifications during production that may affect some of the antibody properties. To this extent, aCD38-b-348-based antibody libraries in which either one or both residues were substituted, and among all such mutants, only a limited number of mutants (e.g., those expressed on the surface of Daudi cells) maintained binding to human CD38 (see Example 2). Thus, the corresponding aCD38-b-348-based antibody variants can be tested as either maintaining all the properties of a CD38-modulating antibody drug or simply having CD38 binding properties. Further validation of these variants can proceed using the assays disclosed in the Examples. This can be done.

[0288] aCD38-a-327 is an antibody that presents novel complementarity determining regions (CDRs, Figure 21A) that do not compete with IB4 or daratumumab for human CD38 binding. Indeed, epitope mapping studies performed using Pepscan technology demonstrated that aCD38-a-327 binds to human CD38 within the regions of amino acids 47-66 and 126-138 (Figure 21B) and binds to human CD38 within the regions of amino acids 47-66 and 126-138 (Figure 21C).-8 It would be shown to bind to the human CD38 extracellular protein sequence with a Kd value in the range of M. Alanine scanning confirms that the epitope region of aCD38-b-348 is involved in binding, specifically, its amino acid residues 58, 64, and 65 of human CD38. Amino acid residue 68 was also shown to be involved, as this residue is sufficiently close to the epitope identified by the Pepscan data, indicating that the correct epitope has been identified.

[0289] Antibody competition assays showed that daratumumab did not compete with aCD38-b-327 for the same epitope (Figure 44C).

[0290] Thus, the aCD38-a-327 sequence (Figure 21A) identifies antibodies that specifically bind to CD38 and their agonist activity can be functionally assessed by cell-based assays or animal models in relation to the functional characteristics that define CD38 modulating antibody agents as that term is used herein.

[0291] Example 2: Cell-based model for testing CD38-modulating antibody agents material and method In vitro T cell activation assay: Pre-frozen primary human pan-T cells (Stemcell Technologies) were labeled with eFluor450 fluorescent dye (Life Technologies) and incubated at 0.15 × 10 6Cells / well were incubated for 72 hours in 96-well flat-bottom plates pre-coated with anti-CD3 antibody (coating concentration of 0.5 or 0.1 μg / mL as indicated, clone OKT3, eBiosciences) and anti-CD38 regulatory antibody at concentrations of 10, 5, and 2.5 μg / mL in RPMI1640 (Life Technologies) containing 10% FBS (Sigma), 2 mM L-glutamine (Life Technologies), and 10,000 U / mL Pen-Strep (Sigma). Readouts of T cell proliferation were obtained by flow cytometry, excluding dead cells labeled with a viability dye (Zombie NIR, BioLegend) and differentiating surface markers by staining with fluorochrome-conjugated antibodies (CD8-FITC clone HIT8a eBiosciences, CD25-PE clone M-A251 Biolegend, CD4-BV510 clone RPA-T4 BioLegend, CD38-PE-Cy7 clone HB7, eBiosciences, CD137-APC clone 4B4-1 BioLegend). Cytokine analysis in supernatants was performed using Meso Scale following the manufacturer's instructions. The assay was performed using the Discovery MSD platform to determine the expression of IFNg, IL2, IL10, TNFa, and GM-CSF (Multiplex Assay Kit, Meso Scale Discovery, asterisks in the figures indicate values ​​beyond the fitted curve range).

[0292] In vitro T cell activation by NFAT signaling assay: Jurkat cells stably transfected with a luciferase reporter system (BPS Bioscience) were incubated in PBS (GIBCO) with different concentrations of mAb (0.2, 1, 5, 10, 20, 40ug / mL) against CD38 (or control IgG) for 20 minutes at 4°C, after which the cells were pelleted, the PBS supernatant was removed, and the cells were incubated with 40ug / mL of F(Ab')2-fragment cross-linking Ab (Jackson ImmunoResearch ) and resuspended in cold growth medium (RPMI (ATCC) + 10% FBS (SIGMA)) in the presence of 1ug / mL soluble CD3 mAb. 10 minutes after addition of the crosslinking antibody, the cells were transferred to a 37°C incubation. 24 hours after the start of the 37°C incubation, the cells were lysed and luciferase activity was measured by the average luminescence release from hydrolysis of a specific luciferase substrate according to the manufacturer's instructions (BPS Bioscience One-Step Luciferase Assay Kit). NFAT signaling is measured in relative luminescence units (RLU).

[0293] In vitro NK cell activation assay. Human PBMCs were labeled with Cell Trace violet proliferation dye (Life Technologies) and cultured in the presence of MDA-MB-231 cells at a ratio of 100:1 (culture medium IMDM, Life Technologies, 10% human serum heat inactivated, Sigma, 10,000U / mL Pen-Strep, Sigma) for 5 days. Anti-CD38 antibodies were added or control cells were left untreated. Proliferation readout, quantified by dilution of the fluorescent dye, was performed by FACS analysis. Cells were labeled with fluorescent dye-conjugated antibodies and NK cells were gated by excluding dead cells (Zombie NIR dye, Biolegend), gating on CD45+ hematopoietic cells (CD45-PE-Cy7, Biolegend) and further gating on CD3-negative CD56-positive cells (CD56-BV711 clone HI30 Biolegend, CD3-BV510 clone OKT3 Biolegend).

[0294] In vitro ADCP assay. For characterization of anti-human CD38 antibodies, antibody-dependent cell-mediated phagocytosis (ADCP) was performed using in vitro differentiated Tregs as target cells and monocyte-derived macrophages as effector cells. Different effector-to-target ratios were evaluated. Target cells were cultured at 1×10 4 cells / well, and effector cells (1 × 10 4 , 2.5×104 , 5×10 4 , or 1 × 10 5 Anti-human CD38 antibodies were evaluated at three concentrations (1 μg / mL, 10 μg / mL, and 50 μg / mL). The assay was performed using the following protocol: PBMCs were isolated from leukocyte cones by Ficoll gradient centrifugation. CD14+ cells were isolated using CD14 Microbeads (CDK006, Miltenyi Biotec). Monocytes were cultured in the presence of 50 ng / mL M-CSF in RPMI1640 (Life Technologies) containing 10% FBS (Sigma), 2 mM L-glutamine (Life Technologies), and 10,000 U / mL Pen-Strep (Sigma) for 7 days, and fresh medium containing M-CSF was added after 4 days. Regulatory T cells (Treg) were isolated using a human Treg cell differentiation kit (130-050-201, R&D Systems). These cells were incubated for 5 days in a humidified incubator at 37°C and 5% CO2. On day 7, macrophages and eFluor450-labeled (eBiosciences) Tregs were co-cultured overnight at the ratios mentioned above in the presence of CD38 or control antibodies. Treg phagocytosis was determined by flow cytometry gating on CD14+ cells (stained with CD14-PE-Cy7 clone MfP9, BD Biosciences) positive for the Treg marker (eFluor450 dye).

[0295] In vitro ADCP reporter assay: Promega Bioassay Core Kit G9901 was used. 5000 Raji cells / well of target wells were plated in 25uL / well of media using 96-well white polystyrene plates (Costar catalogue no. 3917). Test antibodies were serially diluted (1:3) in separate plates. 25uL of serially diluted antibodies were added to the cells. 50000 cells / well of effector cells were added to the plates (25uL / well). Plates were incubated overnight at 37°C for 20 hours. The next day, plates were removed from the incubator and kept at room temperature for 20 minutes. 60uL of Bio-Glo Luciferase Assay Substrate was added to each well and incubated for 30 minutes. Luminescence was read using the GloMax Multi Detection System. Cell culture medium: RPMI + 4% low IgG serum.

[0296] In vitro ADCC assay: For characterization of anti-human CD38 antibodies, antibody-dependent cell-mediated cytotoxicity assays (ADCC assays) were performed using Daudi (CD38 positive) human cell line as target cells and human PBMCs as effector cell sources. Effector to target ratios were evaluated at 50:1 or 25:1 with a top concentration of 10 μg / mL followed by test substances (anti-CD38 primary antibody or daratumumab (or rituximab) as controls) evaluated in a logarithmic dilution series (7 points) in triplicate for 4 hours at 37°C and 5% CO2. PBMCs were stimulated with IL-2, which was present during the co-culture assay. Prior to in vitro culture, target cell lines were labeled with 1 μM calcein AM and incubated with 2.5 mM probenecid. Lysed cells release loaded calcein into the supernatant, which allows fluorescence measurements. Calcein AM release was analyzed by Excel and GraphPad software analysis to generate dose-response curves by normalization using 1% saponin treatment values ​​to determine maximum lysis. Target cell lysis percentage was plotted on an XY chart graphing normalized calcein AM release percentage against the logarithm of concentration, and data was fitted to a nonlinear regression curve from which the EC50 was calculated.

[0297] In vitro CDC assay: CDC activity against a CD38-expressing human cell line (Daudi) was tested by treating cells with test substances (anti-CD38 primary antibody or daratumumab (or rituximab) as control) at a top concentration of 10 μg / mL followed by a logarithmic dilution series (7 points) in triplicate (final concentration of normal human serum complement 10%). Samples were cultured for 3 hours at 37° C. and 5% CO2. Before flow cytometry analysis, cells were washed and resuspended in 1×PBS containing propidium iodide (PI) at a final concentration of 5 μg / mL according to culture conditions. All cells were tested by flow cytometry during sample acquisition. The percentage of PI-positive cells was plotted on an XY chart graphing PI percentage against the logarithm of the concentration, and the data was fitted to a nonlinear regression curve from which the EC50 was calculated.

[0298] Direct cell death assay. Direct pro-apoptotic activity against a CD38-expressing human cell line (Daudi) was tested by treating cells with test substances (anti-CD38 primary antibody) or daratumumab (or rituximab) as controls at a top concentration of 10 μg / mL followed by logarithmic dilution series (7 points) in triplicate. Cell death by Fcγ receptor-mediated cross-linking activity was tested by treating cells with test substances (anti-CD38 primary antibody or rituximab) as controls at a top concentration of 10 μg / mL followed by logarithmic dilution series (7 points) in triplicate, followed by rabbit anti-human Fcγ F(ab')2 (secondary antibody) at 5 μg / mL. Samples were cultured for 24 hours at 37°C and 5% CO2. According to the culture conditions, cells were washed and resuspended in Annexin V binding buffer and 7-AAD, and cell death was tested by flow cytometry analysis. All cells were tested by flow cytometry during sample acquisition. The percentage of late apoptotic cells was plotted on an XY chart graphing the percentage of Annexin V- and 7-AAD-positive cells against the logarithm of the concentration, and the data was fitted to a non-linear regression curve from which the EC50 was calculated.

[0299] Enzymatic activity of CD38 on the cell surface (cyclase activity and NADase / hydrolase activity): Both cyclase and NADase activities of CD38 on the cell surface of Daudi and Jurkat cells were measured by monitoring the CD38-dependent conversion of NGD+ (Sigma) and E-NAD+ (Sigma) to their respective fluorescent products: cGDPR (the cyclic product from NGD+) and 5'-eAMP (the hydrolysis product of E-NAD+). 150,000 Daudi cells were incubated in 75 μL of PBS (Thermo Fisher Scientific). The cells were incubated with 10 μg / mL of antibody in Thermo Fisher for 20 min on ice, and after 20 min, 75 μL of enzyme reaction buffer (or control buffer) was added and Daudi cells were incubated for 45 min at 37°C and Jurkat cells were incubated for 60 min at 37°C. The enzyme reaction buffer contained 20 mM UltraPure Tris-HCI buffer (Thermo Fisher) (pH 7.5), PBS (Thermo Fisher), and 200 μM of either NGD+ or E-NAD+. After incubation at 37°C, cells were pelleted by means of centrifugation at 550×g and 100 μL of supernatant was utilized for fluorescence measurement on a Molecular Devices SpectraMax MiniMax 300 plate reader (excitation wavelength 300 and emission wavelength 410).

[0300] Statistics. Curve fitting was performed using Prism software (GraphPad) to determine EC50 values ​​and maximum activity.

[0301] result The EC50 values ​​and percentage lysis results from the ADCC and CDC assays compared with the results for daratumumab in the same experiments are shown in Tables 2, 3, and 4. [Table 2] [Table 3] [Table 4]

[0302] The aCD38-a-323 candidate antibody was further evaluated on immune cells. In a first series of experiments, aCD38-a-323 shows dose-dependent binding to human T cells (Figure 3B). When tested with T cells, for example when aCD38-a-323 is used to coat plates for the culture of such cells, aCD38-a-323 strongly increases human T cell activation in the presence of anti-CD3 stimulation, while the reference anti-CD38 antibody (DARA) displays weaker agonistic activity (Figure 4A). The agonistic activity of aCD38-a-323 is further strengthened by the stronger inflammatory cytokine secretion by human T cells induced by aCD38-a-323 compared to DARA (Figure 4B). aCD38-a-323 and DARA show comparable activity in ADCC assays (Figure 5A). The lower CDC effect induced by aCD38-323 compared to DARA (Figure 5B) would provide an anti-CD38 antibody with increased safety due to reduced injection site reactions. aCD38-a-323 also showed reduced or no ADCP compared to daratumumab (Figure 26). In addition to in vitro killing activity, aCD38-a-323 potently increased the cyclase activity of CD38 (Figures 6A and 27A), while DARA inhibited the latter activity in both Daudi and Jurkat cell assays. In the Daudi cell assay, aCD38-a-323 reduced the NADase (NAD+ hydrolase) activity of CD38, whereas DARA did not (Figure 6B). In a Jurkat cell assay, aCD38-a-323 decreased the NADase (NAD+ hydrolase) activity of CD38, whereas DARA increased it (Figure 27B).

[0303] In conclusion, aCD38-a-323 was characterized as an exemplary anti-CD38 antibody that displays CD38-modulating antibody drug activity on immune cells in different experimental settings.

[0304] The aCD38-a-306 candidate antibody was further evaluated on immune cells. In a first series of experiments, aCD38-a-306 shows dose-dependent binding to human T cells but not to cynomolgus T cells (Figure 8A and Figure B). When tested with T cells, for example when aCD38-a-306 is used to coat plates for the culture of such cells, aCD38-a-306 increases human T cell activation, while the reference anti-CD38 antibody (DARA) shows weaker agonistic activity (Figure 9A).

[0305] Inflammatory cytokine secretion is similar to that of DARA (Figure 9B). aCD38-a-306 and DARA show comparable activity in ADCC assays (Figure 10A), but only the latter displays CDC activity (Figure 10B). The lack of CDC effect induced by aCD38-a-306 would provide an anti-CD38 antibody with increased safety due to reduced injection site reactions. aCD38-a-323 and aCD38-a-306 are ACD38-a-323 and A ... It also showed no or reduced ADCP compared to daratumumab in a DCP reporter cell assay (Figure 26).

[0306] In addition to in vitro killing activity, aCD38-a-306 reduces CD38 cyclase activity to a lesser extent than DARA, which more potently inhibits cyclase activity in Jurkat cell assays (Figure 27A). aCD38-a-306 strongly reduces CD38 NADase (NAD+ hydrolase) activity, whereas DARA increases it in Jurkat cell assays (Figure 27B).

[0307] In conclusion, aCD38-a-306 was characterized as an exemplary anti-CD38 antibody that displays CD38-modulating antibody drug activity on immune cells in different experimental settings.

[0308] The aCD38-b-329 candidate antibody was further evaluated on immune cells. In a first series of experiments, aCD38-b-329 shows dose-dependent binding to human T cells (Figure 12). When tested with T cells, for example when aCD38-b-329 is used to coat plates for the culture of such cells, aCD38-b-329 increases human T cell activation, while the reference anti-CD38 antibody (DARA) shows weaker agonistic activity (Figure 13A). The agonistic activity of aCD38-b-329 is further strengthened by the stronger inflammatory cytokine secretion by human T cells induced by aCD38-b-329 compared to DARA (Figure 13B). In addition, aCD38-b-329 and DARA show comparable activity in ADCC assays, while aCD38-b-329 shows lower CDC activity (Figure 14A). The reduced CDC effect induced by aCD38-b-329 would provide an anti-CD38 antibody with increased safety due to reduced injection site reactions. DARA and aCD38-b-329 also show comparable activity in killing CD38-expressing tumor cells (Daudi) by human PBMCs, although only the activity of aCD38-b-329 appears to be enhanced by antibody cross-linking (Figure 14B).

[0309] In conclusion, aCD38-b-329 has been characterized as an exemplary anti-CD38 antibody that displays CD38-modulating antibody drug activity on immune cells in different experimental settings.

[0310] The aCD38-b-348 candidate antibody was further evaluated on immune cells. In a first series of experiments, aCD38-b-348 shows dose-dependent binding to human T cells and cynomolgus T cells (Figure 17A and Figure 17B). When tested with T cells, for example when aCD38-b-348 is used to coat plates for the culture of such cells, aCD38-b-348 increases human T cell activation, while the reference anti-CD38 antibody (DARA) displays a much weaker agonistic activity (Figure 18A and Figure 29). When aCD38-b-348 is tested in solution, the antibody induces the proliferation and activation of human primary NK cells co-cultured with breast cancer cell lines (Figure 18B). The agonist activity of aCD38-b-348 is further strengthened by the stronger inflammatory cytokine secretion by human T cells induced by aCD38-b-348 compared to DARA (Figure 18C). The killer activity of aCD38-b-348 appears to be brought about by the induction of macrophage-mediated phagocytosis of CD38-expressing target cells (Figure 19A), e.g., regulatory T cells. This effect is comparable to that of DARA. In addition, aCD38-b-348 and DARA show comparable activity in ADCC assays, but the latter presents higher CDC activity (Figure 19B). The reduced CDC effect induced by aCD38-b-348 would provide an anti-CD38 antibody with increased safety due to reduced injection site reactions. DARA and aCD38-b-348 show comparable activity in killing CD38-expressing tumor cells (Daudi) by human PBMCs, although only the activity of aCD38-b-348 appears to be enhanced by antibody cross-linking (Figure 19C). 48 was shown to have increased ADCP compared to daratumumab in a reporter cell assay (Figure 26).

[0311] In addition to the killing activity in vitro, we showed that aCD38-b-348 slightly decreased the cyclase activity of CD38 (Figure 27A), whereas DARA more strongly inhibited the cyclase activity in the Jurkat cell assay. aCD38-b-348 showed no effect on the NADase (NAD+ hydrolase) activity of CD38, whereas DARA increased its activity in the Jurkat cell assay (Figure 27B).

[0312] In conclusion, aCD38-b-348 has been characterized as an exemplary anti-CD38 antibody that displays CD38-modulating antibody drug activity on immune cells in different experimental settings.

[0313] The aCD38-a-327 candidate antibody was further evaluated on immune cells. aCD38-a-327 and DARA show comparable activity in ADCC assays (Figure 23A). CDC was not induced by aCD38-327 (Figure 23B), which would provide an anti-CD38 antibody with increased safety due to reduced injection site reactions compared to DARA. aCD38-a-327 shows weak induction of apoptosis when crosslinked on target cells (Figures 23C and 23D).

[0314] In addition to the killing activity in vitro, aCD38-a-327 slightly reduces the cyclase activity of CD38 (Figure 24A), while DARA inhibits the latter activity more potently in both Daudi and Jurkat cell assays (aCD38-a-327 reduces activity to 75% and DARA reduces activity to 16% in the Daudi cell assay). aCD38-a-327 does not affect the NADase (NAD+ hydrolase) activity of CD38 (Figures 24B and 27B), while DARA induces an increase in NADase activity in the Daudi and Jurkat cell assays.

[0315] In conclusion, aCD38-a-327 has been characterized as an exemplary anti-CD38 antibody that displays CD38-modulating antibody drug activity on immune cells in different experimental settings.

[0316] The same assay can be performed on the variant antibodies provided herein (i.e., variants of aCD38-a-348 and aCD38-a-329 that have altered DG motifs).

[0317] Example 3: Validation of CD38 Modulating Antibody Agents in Animal Models material and method Lymphoma cell-based models. Daudi and Ramos human Burkitt lymphoma cells were cultured in RPMI 1640 containing 2 mM L-glutamine + 1 mM sodium pyruvate + 4.5 g / L glucose + 10 mM Hepes supplemented with 10% fetal bovine serum. Healthy female cb17 SCID mice were obtained from Charles River. Tumors were grown at 5 x 10 5 Daudi cells or 5 x 10 6 The induction of CD38 expression was induced by intravenous injection of Ramos cells into the tail vein of the animals. Cell injections were performed 24-72 hours after total body irradiation with a γ-ray source (1.44 Gy / mouse, 60Co, BioMep, Bretenières, France). Mice were randomly assigned to treatment groups according to body weight (8 mice per group). Animals in group 1 were intravenously injected with vehicle at 5 mL / kg twice weekly for 3 consecutive weeks (TW×3). Animals in group 2 were intravenously injected with DARA at 10 mg / kg / injection twice weekly for 3 consecutive weeks (TW×3). Animals in groups 3 and 4 were injected with aCD38-b-348 or aCD38-b-32, respectively. 9 was intravenously injected at 10 mg / kg / injection twice a week for 3 consecutive weeks (TW × 3). Mice were sacrificed after a maximum of 72 days.

[0318] Solid Tumor Models The flanks of female CB.17 SCID mice were inoculated with 1 × 10 7 Ramos tumor cells were injected subcutaneously (n=10 / group). 3Treatment began when tumors reached a size of 2000 mm and were treated twice weekly for 3 weeks. Mice were treated intravenously with antibodies aCD38-a-323, aCD38-a-306, aCD38-b-348 at 10 mg / kg compared to daratumumab and vehicle controls. 2 Mice were sacrificed when they reached 0.01 mg / kg or after 60 days, whichever occurred first.

[0319] result The therapeutic properties of aCD38-a-323, aCD38-a-306, and aCD38-b-348 can be tested in animal models of human cancer, specifically using immunodeficient mice, which can better assess the properties of CD38-modulating antibody agents with respect to killing human tumor cells.

[0320] aCD38-b-329 shows remarkable efficacy in increasing survival in mice injected intravenously with two different types of human lymphoma cells, potentially more effective than daratumumab (DARA) (Figure 15).

[0321] aCD38-b-348 shows remarkable efficacy in increasing survival in mice injected intravenously with two different types of human lymphoma cells, an effect superior to that of daratumumab (DARA) (Figure 20).

[0322] These properties, not only in terms of animal survival but also with concomitant immunological effects, can be further investigated in other in vivo models of human tumors (specifically solid cancers) based on the injection of either human cancer lines or human primary cancer cells in which solid tumors grow subcutaneously, as described in the literature (Morton JJ et al. 2016; Holzapfel BM et al., 2015).

[0323] aCD38-b-348 and aCD38-a-306 showed enhanced antitumor activity against subcutaneously injected Ramos cells compared to daratumumab. aCD38-a-323 showed comparable antitumor activity against subcutaneously injected Ramos cells compared to daratumumab (Figure 28).

[0324] The characteristics can be further investigated in ex vivo models based on the use of tumor samples isolated directly from patients from which tumor and immune cells were isolated and tested in vitro for their response to anti-CD38 antibodies (measured by cell activation, proliferation, cytokine production, and / or cell death). Further characteristics such as changes in gene expression in selected tissues or biological materials can be evaluated, possibly by administering aCD38-a-323, aCD38-a-306, aCD38-a-323, aCD38-b-348 at different doses and / or in combination with other anti-cancer agents (kinase or other enzyme inhibitors, antibodies, radiation / chemotherapy, adjuvants, or vaccines, etc.).

[0325] The same assay can be performed on the variant antibodies provided herein (i.e., variants of aCD38-a-348 and aCD38-a-329 that have altered DG motifs).

[0326] Example 4: Low-dose anti-CD38 antibody increases T cell activation in non-human primates Non-human primates (cynomolgus monkeys) were treated intravenously with 0.03 mg / kg aCD38-b-348 on days 1 and 8. Peripheral T cell frequency and activation markers (CD69, CD137, and HLA-DR) were analyzed before the first dose and again 24 hours and 5 days after the second dose. T cells showed signs of increased activation after dosing, most notably with upregulation of CD69 and CD137 on CD4 T cells and HLA-DR on CD8 T cells. No immune activation-related adverse reactions were observed. Results are shown in Figures 32A-F.

[0327] These results demonstrate that this antibody can be used therapeutically in human patients at dosages of 1 mg / kg or less, which is below the current therapeutic dosage used for daratumumab.

[0328] Example 5: Generation of variants of CD38 modulating antibody agents aCD38-b-329 variant To block aspartate isomerization, a library of potential substitutions for the VL CDR3 DG sequence was generated. To remove the DG motif, two yeast libraries were generated for aCD38-b-329. The first library was based on degenerate primers NNKNNK both around the aspartate and glycine. This library had a diversity of 400. The second library was based on degenerate primers NNK, focusing on the aspartate while preserving the glycine, and had a diversity of 20. These libraries were selected in a single round on 10 nM human CD38 monomer and subjected to PSR negative selection. 96 from each line were sequenced, produced, and characterized as described above. In addition, a total of five 96-well plates were selected from the NNKNNK library and screened for binding to rhCD38 on Octet. A limited number of substitutions were tolerated, and the variants showing the best affinity were selected and the variants were tested for binding to rhCD3 on Octet. The variants showing the best affinity were selected for mammalian production and further characterization using the assay described in Example 2.

[0329] result The CDR1-FR2-CDR2-FR3-CDR3 sequences of the VH and VL chains of the variant antibodies are shown in Figure 33. Daudi cell binding experiments confirmed that the binding of the variant antibodies to CD38 was comparable to the parental clone and daratumumab (Figure 34 and Figure 43). [Table 5]

[0330] The variants showed comparable ADCC activity to the parent clone and daratumumab (Figure 35). The variants had a lower EC50 (ug / mL) for ADCC activity than the parent line, but comparable maximum lysis (Table 6). [Table 6]

[0331] Peptide mapping samples were prepared by DTT reduction and iodoacetamide alkylation, digested using trypsin, and analyzed with an LC-UV-MS system. The levels of isomerized and non-isomerized peptides were determined, and the % of isomerized peptides are shown in Table 7. [Table 7]

[0332] aCD38-b-348 variant To block aspartate isomerization, a library of potential substitutions for the VL CDR3 DG sequence was generated. To remove the DG motif, two yeast libraries were generated for aCD38-b-348. The first library was based on degenerate primers NNKNNK both around the aspartate and glycine. This library had a diversity of 400. The second library was based on degenerate primers NNK, focusing on the aspartate while preserving the glycine, and had a diversity of 20. These libraries were selected in a single round on 10 nM human CD38 monomer and subjected to PSR negative selection. 96 from each line were sequenced, produced, and characterized as described above. In addition, a total of five 96-well plates were selected from the NNKNNK library and screened for binding to rhCD38 on Octet. A limited number of substitutions were tolerated, and the variants showing the best affinity were selected and the variants were tested for binding to rhCD3 on Octet. The variants showing the best affinity were selected for mammalian production and further characterization using the assay described in Example 2.

[0333] result The CDR1-FR2-CDR2-FR3-CDR3 sequences of the VH and VL chains of the variant antibodies are shown in Figure 36. Daudi cell binding experiments confirmed that the binding of the variant antibodies to CD38 was comparable to the parental clone and daratumumab (Figure 37). [Table 8]

[0334] The variants showed comparable ADCC activity to the parent clone and daratumumab (Figure 38). The variants had a lower EC50 (ug / mL) for ADCC activity than the parent line, but were comparable in maximum lysis (Table 9). [Table 9]

[0335] Peptide mapping samples were prepared by DTT reduction and iodoacetamide alkylation, digested using trypsin, and analyzed with an LC-UV-MS system. The levels of isomerized and non-isomerized peptides were determined, and the % of isomerized peptides are shown in Table 10. [Table 10]

[0336] Functional characterization of variants: Lymphoma cell-based models, Raji human Burkitt lymphoma cells and Ramos human Burkitt lymphoma cells, were cultured in RPMI 1640 containing 2 mM L-glutamine + 1 mM sodium pyruvate + 4.5 g / L glucose + 10 mM Hepes supplemented with 10% fetal bovine serum. SCID mice were obtained from Charles River. Tumors were grown at 5 × 10 in 200 μL of RPMI 1640. 5 Raji cells or 5 x 10 6The induction was by intravenous injection of Ramos cells into the tail vein of the animals. Cell injections were performed 24–72 h after total body irradiation with a γ-ray source (1.44 Gy / mouse, 60Co, BioMep, Bretenières, France). Mice were randomly divided into treatment groups according to body weight (10 mice per group). Animals in the first group were intravenously injected with vehicle at 5 mL / kg twice weekly for 3 consecutive weeks (TW×3). Animals in the second group were intravenously injected with DARA at 10 mg / kg / injection twice weekly for 3 consecutive weeks (TW×3). Animals in the third group were intravenously injected with aCD38-b-329 at 10 mg / kg / injection twice weekly for 3 consecutive weeks (TW×3). Group 4 animals were intravenously injected with aCD38-b-329-m6 at 10 mg / kg / injection twice weekly for 3 consecutive weeks (TW x 3), group 5 animals were intravenously injected with aCD38-b-329-m7 at 10 mg / kg / injection twice weekly for 3 consecutive weeks (TW x 3), group 6 animals were intravenously injected with aCD38-b-348 at 10 mg / kg / injection twice weekly for 3 consecutive weeks (TW x 3), group 7 animals were intravenously injected with aCD38-b-348-m2 at 10 mg / kg / injection twice weekly for 3 consecutive weeks (TW x 3). Mice were sacrificed at the time points indicated in the figure.

[0337] Results: The therapeutic properties of aCD38 antibodies and their variants were tested in animal models of human cancer, specifically using immunodeficient mice, which allow better evaluation of the properties of CD38-modulating antibody drugs with respect to killing human tumor cells. The aCD38-b-329 variants, aCD38-b-329-m6 and aCD38-b-329-m7, show a remarkable potency in enhancing the survival of mice injected intravenously with two different types of human lymphoma cells, an effect superior to that of daratumumab (DARA) in both models (Raji and Ramos) (Figure 39). A variant of aCD38-b-348, aCD38-b-348-m2, shows a r...

Claims

1. 1. An anti-CD38 antibody or antigen-binding fragment thereof, - exhibits antibody-dependent cell-mediated cytotoxicity (ADCC) activity against CD38+ target cells; - exhibits no complement-dependent cytotoxicity (CDC) activity against CD38+ target cells or exhibits reduced CDC activity compared to daratumumab under the same or substantially the same conditions; -An anti-CD38 antibody or antigen-binding fragment thereof, which induces immune effector cell activation.

2. The antibody or fragment thereof does not exhibit CDC or exhibits CDC in a. with an EC50 at least 0.5-fold higher or at least 1-fold higher than daratumumab, or b. The anti-CD38 antibody or antigen-binding fragment thereof of claim 1, which exhibits a maximum % lysis measured in Raji cells and / or Daudi cells in the presence of 10% complement that is less than or equal to half of the maximum % lysis exhibited by daratumumab.

3. The anti-CD38 antibody or antigen-binding fragment thereof of claim 1, wherein the antibody or antigen-binding fragment thereof induces CDC with an EC50 value of greater than 0.05 μg / mL on Daudi cells and / or Raji cells in the presence of 10% complement.

4. The anti-CD38 antibody or antigen-binding fragment thereof of claim 1, wherein the reduction in CDC activity is such that the EC50 of the antibody or antigen-binding fragment thereof is at least 0.5-fold or at least 1-fold higher than the EC50 of daratumumab under the same or substantially the same conditions.

5. The anti-CD38 antibody or antigen-binding fragment thereof of claim 1, wherein the reduced CDC activity compared to daratumumab is such that the maximum % cytolysis is less than or equal to half of the maximum % cytolysis exhibited by daratumumab under the same or substantially the same conditions.

6. The anti-CD38 antibody or antigen-binding fragment thereof according to any one of claims 1 to 5, wherein the antibody or antigen-binding fragment thereof exhibits antibody-dependent cellular phagocytosis (ADCP) against CD38-expressing cells.

7. The anti-CD38 antibody or antigen-binding fragment thereof according to any one of claims 1 to 5, wherein the antibody or antigen-binding fragment thereof does not exhibit ADCP activity against CD38-expressing cells.

8. The anti-CD38 antibody or antigen-binding fragment thereof of any one of claims 1 to 7, wherein the antibody or antigen-binding fragment thereof induces T cell activation.

9. 9. The anti-CD38 antibody or antigen-binding fragment thereof of claim 8, wherein the NFAT signaling of the antibody or antigen-binding fragment thereof is at least 20% greater than the NFAT signaling of daratumumab when T cell activation is determined by measuring NFAT signaling in luciferase reporter Jurkat cells.

10. 10. The anti-CD38 antibody or antigen-binding fragment thereof of claim 8 or claim 9, wherein T cell activation is characterized by increased T cell proliferation and / or increased cytokine secretion, said cytokine being selected from the group consisting of IL-2, TNF-α, IFN-γ, IL-10, and GM-CSF.

11. The anti-CD38 antibody or antigen-binding fragment thereof of any one of claims 1 to 10, wherein the antibody or antigen-binding fragment thereof increases T cell proliferation in CD4+ cells and / or CD8+ cells by at least 20% compared to untreated cells.

12. 12. The anti-CD38 antibody or antigen-binding fragment thereof of any one of claims 1 to 11, wherein the antibody or antigen-binding fragment thereof induces secretion of a cytokine selected from the group consisting of IL-2, TNF-α, IFN-γ, IL-10, and / or GM-CSF in CD4+ and / or CD8+ cells in an amount that exceeds the secretion induced by daratumumab under the same or substantially the same conditions.

13. The anti-CD38 antibody or antigen-binding fragment thereof of any one of claims 1 to 12, wherein the antibody or antigen-binding fragment thereof induces NK cell activation.

14. The anti-CD38 antibody or antigen-binding fragment thereof of claim 13, wherein the NK cell activation is characterized by increased NK cell proliferation, increased intracellular IFNg, and / or increased expression of CD107a.

15. The anti-CD38 antibody or antigen-binding fragment thereof according to any one of claims 1 to 14, wherein the antibody or antigen-binding fragment thereof has an inhibitory effect on CD38 NADase activity.

16. The anti-CD38 antibody or antigen-binding fragment thereof of claim 15, wherein the inhibitory effect on the CD38 NADase activity is at least 10% lower compared to the CD38 NADase activity in the presence of a non-IgG binding control antibody as measured by the conversion of E-NAD+ to 5'-eAMP in Jurkat cells.

17. The anti-CD38 antibody or antigen-binding fragment thereof of claim 15 or 16, wherein the anti-CD38 antibody or antigen-binding fragment thereof reduces CD38 NADase activity to 25% or more of the CD38 NADase activity in the presence of a non-IgG binding control antibody as measured by the conversion of E-NAD+ to 5'-eAMP in Jurkat cells.

18. The anti-CD38 antibody or antigen-binding fragment thereof according to any one of claims 1 to 17, wherein the antibody has a stimulatory effect on CD38 cyclase activity.

19. 19. The anti-CD38 antibody or antigen-binding fragment thereof of claim 18, wherein the CD38 cyclase activity is at least 10% higher than the CD38 cyclase activity in the presence of a non-IgG binding control antibody as measured by conversion of NGD+ to cGDPR in Jurkat cells.

20. The anti-CD38 antibody or antigen-binding fragment thereof according to any one of claims 1 to 17, wherein the antibody has an inhibitory effect on CD38 cyclase activity.

21. The anti-CD38 antibody or antigen-binding fragment thereof of claim 20, wherein the inhibitory effect on the CD38 cyclase activity is at least 10% lower compared to the CD38 cyclase activity in the presence of a non-IgG binding control antibody as measured by conversion of NGD+ to cGDPR in Jurkat cells.

22. The anti-CD38 antibody or antigen-binding fragment thereof of claim 20 or 21, wherein the anti-CD38 antibody or antigen-binding fragment thereof reduces CD38 cyclase activity to 25% or more of the CD38 cyclase activity in the presence of a non-IgG binding control antibody as measured by conversion of NGD+ to cGDPR in Jurkat cells.

23. 23. The anti-CD38 antibody or antigen-binding fragment thereof of any one of claims 1 to 22, wherein the antibody or antigen-binding fragment thereof is a monoclonal antibody, a domain antibody, a single chain antibody, a Fab fragment, an F(ab')2 fragment, a single chain variable fragment (scFv), an scFv-Fc fragment, a single chain antibody (scAb), or a nanobody single domain antibody.

24. The anti-CD38 antibody or antigen-binding fragment thereof of any one of claims 1 to 23, wherein the antibody or antigen-binding fragment thereof is a rabbit, murine, chimeric, humanized, or fully human antigen-binding antibody.

25. The anti-CD38 antibody or antigen-binding fragment thereof of any one of claims 1 to 24, wherein the antibody is selected from the group consisting of IgG1, IgG2, IgG3, and IgG4 isotype antibodies.

26. 26. The anti-CD38 antibody or antigen-binding fragment thereof of any one of claims 1 to 25, wherein the antibody or antigen-binding fragment thereof is comprised in a bispecific antibody, a multispecific antibody, or an immunoconjugate further comprising a therapeutic or diagnostic agent.

27. The anti-CD38 antibody or antigen-binding fragment thereof of any one of claims 1 to 26, wherein the antibody or antigen-binding fragment thereof binds to the extracellular domain of human CD38.

28. which specifically binds to an epitope of human CD38, said epitope comprising at least amino acids 65 to 79 of SEQ ID NO: 47, - amino acids 47 to 66 and 126 to 138, and optionally amino acid 68, of SEQ ID NO: 47, or - An anti-CD38 antibody or antigen-binding fragment thereof according to any of claims 1 to 27, comprising amino acids 120, 121, 141 and optionally 241 of SEQ ID NO:

47.

29. The anti-CD38 antibody or antigen-binding fragment thereof according to any one of claims 1 to 27, wherein the antibody or antigen-binding fragment thereof comprises the aCD38-b-348-HCDR3 amino acid sequence as variable heavy chain complementarity determining region 3.

30. a) the amino acid sequence aCD38-b-348-HCDR1 as variable heavy chain complementarity determining region 1, and The anti-CD38 antibody or antigen-binding fragment thereof according to any one of claims 28 to 31, further comprising the aCD38-b-348-HCDR2 amino acid sequence as variable heavy chain complementarity determining region 2.

31. a) the amino acid sequence aCD38-b-348-LCDR1 as variable light chain complementarity determining region 1; b) the aCD38-b-348-LCDR2 amino acid sequence as variable light chain complementarity determining region 2, and c) the aCD38 antibody or antigen-binding fragment thereof according to claim 29 or 30, further comprising the aCD38-b-348-LCDR3 amino acid sequence as variable light chain complementarity determining region 3.

32. 32. The anti-CD38 antibody or antigen-binding fragment thereof of claim 29, 30, or 31, wherein the antibody or antigen-binding fragment thereof comprises a variable heavy chain comprising the amino acid sequence aCD38-b-348-HCDR123.

33. The anti-CD38 antibody or antigen-binding fragment thereof of any one of claims 28 to 32, wherein the antibody or antigen-binding fragment thereof further comprises a variable light chain comprising the aCD38-b-348-LCDR123 amino acid sequence.

34. The anti-CD38 antibody or antigen-binding fragment thereof of any one of claims 31 to 33, wherein the antibody or antigen-binding fragment thereof is mutated to remove the DG motif in the LCDR3 region.

35. 35. The anti-CD38 antibody or antigen-binding fragment thereof of claim 34, wherein the antibody or antigen-binding fragment thereof comprises an LCDR3 region selected from the group consisting of QQEANVYT, QQDSNVYT, QQDANVYT, and QQEGNVYT.

36. the antibody or antigen-binding fragment thereof a) an antibody or antigen-binding fragment thereof comprising an HCDR1 comprising the sequence of SEQ ID NO:25, an HCDR2 comprising the sequence of SEQ ID NO:26, an HCDR3 comprising the sequence of SEQ ID NO:27, an LCDR1 comprising the sequence of SEQ ID NO:29, an LCDR2 comprising the sequence of SEQ ID NO:30, and an LCDR3 comprising the sequence of SEQ ID NO:31; b) an antibody or antigen-binding fragment thereof comprising an HCDR1 comprising the sequence of SEQ ID NO:25, an HCDR2 comprising the sequence of SEQ ID NO:26, an HCDR3 comprising the sequence of SEQ ID NO:27, an LCDR1 comprising the sequence of SEQ ID NO:29, an LCDR2 comprising the sequence of SEQ ID NO:30, and an LCDR3 comprising the sequence of SEQ ID NO:43; c) an antibody or antigen-binding fragment thereof comprising an HCDR1 comprising the sequence of SEQ ID NO:25, an HCDR2 comprising the sequence of SEQ ID NO:26, an HCDR3 comprising the sequence of SEQ ID NO:27, an LCDR1 comprising the sequence of SEQ ID NO:29, an LCDR2 comprising the sequence of SEQ ID NO:30, and an LCDR3 comprising the sequence of SEQ ID NO:44; d) an antibody or antigen-binding fragment thereof comprising an HCDR1 comprising the sequence of SEQ ID NO:25, an HCDR2 comprising the sequence of SEQ ID NO:26, an HCDR3 comprising the sequence of SEQ ID NO:27, an LCDR1 comprising the sequence of SEQ ID NO:29, an LCDR2 comprising the sequence of SEQ ID NO:30, and an LCDR3 comprising the sequence of SEQ ID NO:45; e) an antibody or antigen-binding fragment thereof comprising an HCDR1 comprising the sequence of SEQ ID NO:25, an HCDR2 comprising the sequence of SEQ ID NO:26, an HCDR3 comprising the sequence of SEQ ID NO:27, an LCDR1 comprising the sequence of SEQ ID NO:29, an LCDR2 comprising the sequence of SEQ ID NO:30, and an LCDR3 comprising the sequence of SEQ ID NO:46; f) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO:28 and a light chain variable region comprising the sequence of SEQ ID NO:32; g) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO:28 and a light chain variable region comprising the sequence of SEQ ID NO:58; h) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO:28 and a light chain variable region comprising the sequence of SEQ ID NO:59; i) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO: 28 and a light chain variable region comprising the sequence of SEQ ID NO: 60; j) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO: 28 and a light chain variable region comprising the sequence of SEQ ID NO: 61; k) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO: 54 and a light chain variable region comprising the sequence of SEQ ID NO: 55; l) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO:54 and a light chain variable region comprising the sequence of SEQ ID NO:64; m) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO:54 and a light chain variable region comprising the sequence of SEQ ID NO:65; n) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO:54 and a light chain variable region comprising the sequence of SEQ ID NO:66; and o) An anti-CD38 antibody or antigen-binding fragment thereof according to any one of claims 28 to 35, selected from the group consisting of an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO:54 and a light chain variable region comprising the sequence of SEQ ID NO:

67.

37. The anti-CD38 antibody or antigen-binding fragment thereof according to any one of claims 1 to 27, wherein the antibody or antigen-binding fragment thereof comprises the aCD38-a-323-HCDR3 amino acid sequence as variable heavy chain complementarity determining region 3.

38. a) the aCD38-a-323-HCDR1 amino acid sequence as variable heavy chain complementarity determining region 1, and The anti-CD38 antibody or antigen-binding fragment thereof according to claim 37, further comprising the aCD38-a-323-HCDR2 amino acid sequence as variable heavy chain complementarity determining region 2.

39. a) the aCD38-a-323-LCDR1 amino acid sequence as variable light chain complementarity determining region 1; b) the aCD38-a-323-LCDR2 amino acid sequence as variable light chain complementarity determining region 2, and c) the aCD38 antibody or antigen-binding fragment thereof according to claim 37 or 38, further comprising the aCD38-a-323-LCDR3 amino acid sequence as variable light chain complementarity determining region 3.

40. 40. The anti-CD38 antibody or antigen-binding fragment thereof of claim 37, 38, or 39, wherein the antibody or antigen-binding fragment thereof comprises a variable heavy chain comprising the amino acid sequence aCD38-a-323-HCDR123.

41. The anti-CD38 antibody or antigen-binding fragment thereof of any one of claims 37 to 40, wherein the antibody or antigen-binding fragment thereof further comprises a variable light chain comprising the aCD38-a-323-LCDR123 amino acid sequence.

42. the antibody or antigen-binding fragment thereof a) an antibody or antigen-binding fragment thereof comprising an HCDR1 comprising the sequence of SEQ ID NO:1, an HCDR2 comprising the sequence of SEQ ID NO:2, an HCDR3 comprising the sequence of SEQ ID NO:3, an LCDR1 comprising the sequence of SEQ ID NO:5, an LCDR2 comprising the sequence of SEQ ID NO:6, and an LCDR3 comprising the sequence of SEQ ID NO:7; b) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO:4 and a light chain variable region comprising the sequence of SEQ ID NO:8; c) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO: 48 and a light chain variable region comprising the sequence of SEQ ID NO: 49; and d) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO: 72 and a light chain variable region comprising the sequence of SEQ ID NO:

73.

43. The anti-CD38 antibody or antigen-binding fragment thereof according to any one of claims 1 to 27, wherein the antibody or antigen-binding fragment thereof comprises the aCD38-a-306-HCDR3 amino acid sequence as variable heavy chain complementarity determining region 3.

44. a) the aCD38-a-306-HCDR1 amino acid sequence as variable heavy chain complementarity determining region 1, and The anti-CD38 antibody or antigen-binding fragment thereof according to claim 43, further comprising the aCD38-a-306-HCDR2 amino acid sequence as variable heavy chain complementarity determining region 2.

45. a) the aCD38-a-306-LCDR1 amino acid sequence as variable light chain complementarity determining region 1; b) the aCD38-a-306-LCDR2 amino acid sequence as the variable light chain complementarity determining region 2, and c) the aCD38 antibody or antigen-binding fragment thereof according to claim 43 or 44, further comprising the aCD38-a-306-LCDR3 amino acid sequence as variable light chain complementarity determining region 3.

46. The anti-CD38 antibody or antigen-binding fragment thereof of claim 43, 44, or 45, wherein the antibody or antigen-binding fragment thereof comprises a variable heavy chain comprising the amino acid sequence aCD38-a-306-HCDR123.

47. 47. The anti-CD38 antibody or antigen-binding fragment thereof of any one of claims 43 to 46, wherein the antibody or antigen-binding fragment thereof further comprises a variable light chain comprising the aCD38-a-306-LCDR123 amino acid sequence.

48. the antibody or antigen-binding fragment thereof a) an antibody or antigen-binding fragment thereof comprising an HCDR1 comprising the sequence of SEQ ID NO:9, an HCDR2 comprising the sequence of SEQ ID NO:10, an HCDR3 comprising the sequence of SEQ ID NO:11, an LCDR1 comprising the sequence of SEQ ID NO:13, an LCDR2 comprising the sequence of SEQ ID NO:14, and an LCDR3 comprising the sequence of SEQ ID NO:15; b) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO: 12 and a light chain variable region comprising the sequence of SEQ ID NO: 16; c) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO:50 and a light chain variable region comprising the sequence of SEQ ID NO:51; and d) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO: 74 and a light chain variable region comprising the sequence of SEQ ID NO:

75.

49. The anti-CD38 antibody or antigen-binding fragment thereof according to any one of claims 1 to 27, wherein the antibody or antigen-binding fragment thereof comprises the aCD38-b-329-HCDR3 amino acid sequence as variable heavy chain complementarity determining region 3.

50. a) the amino acid sequence aCD38-b-329-HCDR1 as variable heavy chain complementarity determining region 1, and The anti-CD38 antibody or antigen-binding fragment thereof according to claim 49, further comprising the aCD38-a-309-HCDR2 amino acid sequence as variable heavy chain complementarity determining region 2.

51. a) the amino acid sequence aCD38-b-329-LCDR1 as variable light chain complementarity determining region 1; b) the aCD38-b-329-LCDR2 amino acid sequence as variable light chain complementarity determining region 2, and c) the aCD38 antibody or antigen-binding fragment thereof according to claim 49 or 50, further comprising the aCD38-b-329-LCDR3 amino acid sequence as variable light chain complementarity determining region 3.

52. The antibody or antigen-binding fragment thereof is aCD38-b-329-HCDR123 amino acid 52. The anti-CD38 antibody or antigen-binding fragment thereof of claim 49, 50, or 51, comprising a variable heavy chain comprising an amino acid sequence.

53. 53. The anti-CD38 antibody or antigen-binding fragment thereof of any one of claims 49 to 52, wherein the antibody or antigen-binding fragment thereof further comprises a variable light chain comprising the aCD38-b-329-LCDR123 amino acid sequence.

54. 54. The anti-CD38 antibody or antigen-binding fragment thereof of any one of claims 49 to 53, wherein the antibody or antigen-binding fragment thereof is mutated to remove the DG motif in the LCDR3 region.

55. 55. The anti-CD38 antibody or antigen-binding fragment thereof of claim 54, wherein the antibody or antigen-binding fragment thereof comprises an LCDR3 region selected from the group consisting of QQDEAVFT and QQDSAVFT.

56. the antibody or antigen-binding fragment thereof a) an antibody or antigen-binding fragment thereof comprising an HCDR1 comprising the sequence of SEQ ID NO: 17, an HCDR2 comprising the sequence of SEQ ID NO: 18, an HCDR3 comprising the sequence of SEQ ID NO: 19, an LCDR1 comprising the sequence of SEQ ID NO: 21, an LCDR2 comprising the sequence of SEQ ID NO: 22, and an LCDR3 comprising the sequence of SEQ ID NO: 23; b) an antibody or antigen-binding fragment thereof comprising an HCDR1 comprising the sequence of SEQ ID NO: 17, an HCDR2 comprising the sequence of SEQ ID NO: 18, an HCDR3 comprising the sequence of SEQ ID NO: 19, an LCDR1 comprising the sequence of SEQ ID NO: 21, an LCDR2 comprising the sequence of SEQ ID NO: 22, and an LCDR3 comprising the sequence of SEQ ID NO: 41; c) an antibody or antigen-binding fragment thereof comprising an HCDR1 comprising the sequence of SEQ ID NO: 17, an HCDR2 comprising the sequence of SEQ ID NO: 18, an HCDR3 comprising the sequence of SEQ ID NO: 19, an LCDR1 comprising the sequence of SEQ ID NO: 21, an LCDR2 comprising the sequence of SEQ ID NO: 22, and an LCDR3 comprising the sequence of SEQ ID NO: 42; d) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO: 20 and a light chain variable region comprising the sequence of SEQ ID NO: 24; e) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO: 20 and a light chain variable region comprising the sequence of SEQ ID NO: 62; f) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO: 20 and a light chain variable region comprising the sequence of SEQ ID NO: 63; g) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO:52 and a light chain variable region comprising the sequence of SEQ ID NO:53; h) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO:52 and a light chain variable region comprising the sequence of SEQ ID NO:68; and i) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO:52 and a light chain variable region comprising the sequence of SEQ ID NO:

69.

57. The anti-CD38 antibody or antigen-binding fragment thereof according to any one of claims 1 to 27, wherein the antibody or antigen-binding fragment thereof comprises the aCD38-a-327-HCDR3 amino acid sequence as variable heavy chain complementarity determining region 3.

58. a) the aCD38-a-327-HCDR1 amino acid sequence as variable heavy chain complementarity determining region 1, and b) the aCD38 antibody or antigen-binding fragment thereof according to claim 57, further comprising the aCD38-a-327-HCDR2 amino acid sequence as variable heavy chain complementarity determining region 2.

59. a) the aCD38-a-327LCDR1 amino acid sequence as variable light chain complementarity determining region 1; b) the aCD38-a-327-LCDR2 amino acid sequence as variable light chain complementarity determining region 2, and c) the anti-CD38 antibody or antigen-binding fragment thereof according to claim 57 or 58, further comprising the aCD38-a-327-LCDR3 amino acid sequence as variable light chain complementarity determining region 3.

60. 60. The anti-CD38 antibody or antigen-binding fragment thereof of claim 57, 58, or 59, wherein the antibody or antigen-binding fragment thereof comprises a variable heavy chain comprising the amino acid sequence aCD38-a-327-HCDR123.

61. 61. The anti-CD38 antibody or antigen-binding fragment thereof of any one of claims 57 to 60, wherein the antibody or antigen-binding fragment thereof further comprises a variable light chain comprising the aCD38-a-327-LCDR123 amino acid sequence.

62. the antibody or antigen-binding fragment thereof a) an antibody or antigen-binding fragment thereof comprising an HCDR1 comprising the sequence of SEQ ID NO:33, an HCDR2 comprising the sequence of SEQ ID NO:34, an HCDR3 comprising the sequence of SEQ ID NO:35, an LCDR1 comprising the sequence of SEQ ID NO:37, an LCDR2 comprising the sequence of SEQ ID NO:38, and an LCDR3 comprising the sequence of SEQ ID NO:39; b) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO: 36 and a light chain variable region comprising the sequence of SEQ ID NO: 40; c) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO:56 and a light chain variable region comprising the sequence of SEQ ID NO:57; and d) an antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising the sequence of SEQ ID NO: 76 and a light chain variable region comprising the sequence of SEQ ID NO: 77;

63. 63. The anti-CD38 antibody or antigen-binding fragment thereof of any one of claims 1 to 62, wherein the antibody or antigen-binding fragment thereof is defucosylated.

64. An affinity matured variant of an antibody or antigen-binding fragment thereof according to any one of claims 1 to 63.

65. A nucleic acid molecule encoding the antibody or antigen-binding fragment thereof according to any one of claims 1 to 64.

66. 66. A nucleic acid vector comprising the nucleic acid molecule of claim 65.

67. 67. A host cell comprising the nucleic acid vector of claim 66.

68. 68. A method for producing an antibody or antigen-binding fragment thereof according to any one of claims 1 to 64, comprising culturing a host cell according to claim 67.

69. A composition comprising an antibody or antigen-binding fragment thereof according to any one of claims 1 to 64.

70. 70. The composition of claim 69, further comprising a pharma- ceutically acceptable carrier or excipient.

71. 71. The composition of claim 69 or claim 70, wherein the composition is for use in the treatment of cancer.

72. 70. Use of an antibody or antigen-binding fragment thereof according to any one of claims 1 to 64, or a composition according to claim 69, in the manufacture of a medicament for treating cancer.

73. 71. A method of treating cancer in a subject, comprising administering to the subject an effective amount of the composition of claim 70.

74. 74. The method of claim 73, further comprising administering to the subject a second agent simultaneously or sequentially in any order.

75. 75. The method of claim 73 or 74, wherein the subject has a solid tumor.

76. 75. The method of claim 73 or 74, wherein the subject has a hematological cancer.

77. 65. A method of preparing an anti-CD38 antibody, comprising providing an antibody according to any one of claims 1 to 64 and subjecting said antibody to affinity maturation, wherein the anti-CD38 antibody produced has a higher affinity for CD38 than the parent antibody.

78. 78. A method of preparing a pharmaceutical composition, comprising providing an antibody prepared according to the method of claim 77 and co-formulating the antibody with at least one or more pharma- ceutically acceptable excipients.

Images