Methods and compositions for treating systemic lupus erythematosus (SLE) with mosunetuzumab

Abstract

Disclosed herein are compositions and methods for the treatment of systemic lupus erythematosus using anti-CD20 / anti-CD3 bispecific antibodies, such as mosunetuzumab.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Application No. 63 / 264,139, filed November 16, 2021, and U.S. Provisional Application No. 63 / 378,353, filed October 19, 2022, the entire contents of each of which are incorporated by reference into this specification.

[0002] Sequence Listing

[0002] This application contains a Sequence Listing that has been submitted electronically in XML format, and is incorporated herein by reference in its entirety. Said XML copy, created on November 1, 2022, is named P36994-WO_sequence_listing.xml and is 46.2 bytes in size. [Background technology]

[0003] Systemic lupus erythematosus

[0004] Systemic lupus erythematosus (SLE) is an autoimmune rheumatic disease that primarily affects women of childbearing age. SLE is characterized by multiorgan involvement and immunological abnormalities, including B-cell and T-cell dysfunction. Much of the tissue damage is thought to result from autoantibody formation and immune complex deposition, but the underlying cause is unknown. Disease symptoms range from mild to severe, potentially life-threatening, and can show acute, subacute, and chronic patterns of progression. The protean and heterogeneous nature of SLE makes it particularly challenging to diagnose and manage. Current standard treatments for SLE include oral corticosteroids (OCS), antimalarial therapies (e.g., hydroxychloroquine, chloroquine, quinacrine), and traditional immunosuppressants (e.g., mycophenolate mofetil [MMF], azathioprine, methotrexate). More recently, the B-lymphocyte stimulator inhibitor belimumab (Benlysta) was approved for the treatment of patients with active autoantibody-positive SLE who are receiving standard treatment (Burness and McCormack 2011). These drugs generally have limited efficacy against inflammatory manifestations of SLE and their use is often limited by toxicity. For example, corticosteroids are effective against many manifestations of SLE but have significant short-term and long-term side effects, including infections, osteoporosis, hyperglycemia, and hyperlipidemia. There is a high unmet medical need in SLE. Despite available treatments, SLE patients remain at high risk for damage accumulation, cardiovascular disease, treatment complications, and mortality (Cook et al. 2000; Gladman et al. 2002; Nossent et al. 2010, Lopez et al. 2012). The risk of death is estimated to be 1.3-5.3 times higher than in age-matched controls from the general population in the same region (Singh and Yen, 2018). SLE is one of the leading causes of death in young women (15-24 years) in the United States (Yen and Singh 2018).

[0004] Mosunetuzumab

[0005] Mosunetuzumab is a full-length humanized anti-cluster of differentiation 20 (CD20) / CD3 cell-dependent bispecific antibody of the immunoglobulin (Ig) G1 isotype, manufactured using knob-into-hole technology (Atwell et al. 1997; Spiess et al. 2013). One antigen-binding fragment (Fab) region of the antibody is directed to the extracellular domain of the CD3ε subunit of the T-cell receptor complex, and the other Fab region is directed to the extracellular domain of CD20 (Atwell et al. 1997; Spiess et al. 2013). Mosunetuzumab contains an N297G amino acid substitution in the fragment crystallizable (Fc) region by EU numbering (Edelman et al. 1969; Kabat et al. 1991). This substitution results in an aglycosylated heavy chain that has minimal binding to Fcγ receptors, resulting in attenuated Fc-dependent cell effector functions. Mosunetuzumab is produced from Chinese hamster ovary cells. As a T cell-engaging bispecific antibody, mosunetuzumab is a conditional agonist; that is, killing of the target B cell is observed only upon simultaneous binding to CD20 on B cells and CD3 on T cells. Engagement of both arms of mosunetuzumab results in the formation of an immunological synapse between the target B cell and the cytotoxic T cell, resulting in target- and dose-dependent T cell activation. T cell activation is indicated by the expression of activation-associated surface markers (e.g., CD69 and CD25), the transient release of cytokines (e.g., interferon-gamma [IFN-γ], tumor necrosis factor-alpha [TNF-α], interleukin [IL]-2, 6, and 10), and robust proliferation of T cells. Subsequent release of perforin and a cocktail of granule enzymes from the T cell through the immunological synapse results in B cell lysis.

[0005]

[0006] Other technical features will be readily apparent to those skilled in the art from the following drawings, specifications, and claims. Summary of the Invention

[0006] The present invention relates to the treatment of systemic lupus erythematosus. More specifically, the present invention relates to the treatment of subjects with systemic lupus erythematosus by administration of mosunetuzumab, a bispecific antibody that binds to cluster of differentiation 20 (CD20) and cluster of differentiation 3 (CD3).

[0007]

[0007] In a first aspect, provided herein is a method of treating a patient, the method comprising administering an effective amount of mosunetuzumab to the patient when the patient suffers from systemic lupus erythematosus. The method may also include where administering an effective amount of mosunetuzumab comprises administering mosunetuzumab according to a dosing regimen comprising at least a first dosing cycle, the first dosing cycle comprising a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is less than C1D2, C1D1 is between about 1.6 mg and about 5 mg, and C1D2 is between about 15 mg and about 60 mg. The method may also include where mosunetuzumab is administered subcutaneously. The method may also include where the patient is further administered tocilizumab when the patient experiences cytokine release syndrome (CRS). The method may include administering to the patient a corticosteroid, cyclophosphamide, B cell depletion therapy, or a calcineurin inhibitor.

[0008]

[0008] In another aspect, provided herein is a method of treating a patient, comprising administering an effective amount of mosunetuzumab to the patient, wherein (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, wherein the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, wherein C1D1 is between about 1.6 mg and about 5 mg on day 1 of the cycle, and C1D2 is between about 15 mg and about 60 mg on day 8 of the cycle, and (c) the mosunetuzumab is administered subcutaneously. The method may also include where C1D1 is 1.6 mg. The method may also include where C1D1 is 5 mg. The method may also include where C1D2 is 15 mg. The method may also include where C1D2 is 45 mg. The method may also include when C1D2 is 60 mg. The method may also include when C1D1 is 1.6 mg and C1D2 is 15 mg. The method may also include when C1D1 is 1.6 mg and C1D2 is 45 mg. The method may also include when C1D1 is 1.6 mg and C1D2 is 60 mg. The method may also include when C1D1 is 5 mg and C1D2 is 15 mg. The method may also include when C1D1 is 5 mg and C1D2 is 45 mg. The method may also include when C1D1 is 5 mg and C1D2 is 60 mg. The method may also include when at least one symptom of SLE is reduced. The method may also include when mosunetuzumab is administered subcutaneously. The method may also further include administering to the patient a corticosteroid, cyclophosphamide, B cell depletion therapy, or a calcineurin inhibitor.

[0009]

[0009] In yet another aspect, a method of treating patients that are part of a patient population includes administering an effective amount of mosunetuzumab to the patients, where each patient of the patient population suffers from systemic lupus erythematosus. The method may also include where at least one symptom of SLE is reduced in at least one patient in the patient population. The method may also include where administering an effective amount of mosunetuzumab includes administering mosunetuzumab according to a dosing regimen that includes at least a first dosing cycle, where the first dosing cycle includes a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is less than C1D2, C1D1 is between about 1.6 mg and about 5 mg, and C1D2 is between about 15 mg and about 60 mg. The method may also include where mosunetuzumab is administered subcutaneously. The method may further comprise administering to the patient a corticosteroid, cyclophosphamide, B cell depletion therapy, or a calcineurin inhibitor.

[0010]

[0010] In another aspect, a method of treating a patient of a patient population includes administering an effective amount of mosunetuzumab to the patient, where (a) the patient population has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is between about 1.6 mg and about 5 mg on day 1 of the cycle and C1D2 is between about 15 mg and about 60 mg on day 8 of the cycle, and (c) the mosunetuzumab is administered subcutaneously. The method may also include where C1D1 is 1.6 mg. The method may also include where C1D1 is 5 mg. The method may also include where C1D2 is 15 mg. The method may also include where C1D2 is 45 mg. The method may also include when C1D2 is 60 mg. The method may also include when C1D1 is 1.6 mg and C1D2 is 15 mg. The method may also include when C1D1 is 1.6 mg and C1D2 is 45 mg. The method may also include when C1D1 is 1.6 mg and C1D2 is 60 mg. The method may also include when C1D1 is 5 mg and C1D2 is 15 mg. The method may also include when C1D1 is 5 mg and C1D2 is 45 mg. The method may also include when C1D1 is 5 mg and C1D2 is 60 mg. The method may also include when at least one symptom of SLE is reduced. The method may also include when mosunetuzumab is administered subcutaneously.

[0011]

[0011] In yet another aspect, a kit is provided that includes (a) a first container containing mosunetuzumab, and (b) a package insert containing instructions for providing treatment to a patient with systemic lupus erythematosus, wherein mosunetuzumab is administered subcutaneously and according to a dosing regimen comprising at least a first dosing cycle, wherein the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, wherein C1D1 is between about 1.6 mg and about 5 mg and is administered on day 1 of the cycle, and C1D2 is between about 15 mg and about 60 mg and is administered on day 8 of the cycle. The kit may also include where C1D1 is 1.6 mg and C1D2 is 15 mg. The kit may also include where C1D1 is 1.6 mg and C1D2 is 45 mg. The kit may also include where C1D1 is 1.6 mg and C1D2 is 60 mg. The kit may also include where C1D1 is 5 mg and C1D2 is 15 mg. The kit may also include where C1D1 is 5 mg and C1D2 is 45 mg. The kit may also include where C1D1 is 5 mg and C1D2 is 60 mg. The kit may also include where mosunetuzumab is included in an injection device. The kit may also further include a second container. The kit may also include where the injection device is a syringe or an autoinjector. The kit may also include where the first container includes an injection device containing sufficient mosunetuzumab to deliver a first dose and the second container includes an injection device containing sufficient mosunetuzumab to deliver a second dose. The kit may also further include at least a third container. The kit may also include where a third container contains a medicament and the instructions further provide directions for administering the medicament.

[0012]

[0012] Other technical features will be readily apparent to those skilled in the art from the following drawings, specification, and claims. [Brief description of the drawings]

[0013] [Figure 1] 1 shows a schema of the tests discussed in this disclosure, including examples. [Diagram 2]

[0014]

[0023] Figure 1 shows the study timeline discussed in this disclosure, including examples. DLT = dose-limiting toxicity, EOS = end of study. Visits within the DLT evaluation period and visits beyond month 12 are not shown. [Diagram 3]

[0015] 1 shows an example of the Patient Global Impression of Severity (PGI-S) discussed in this disclosure, including the Examples. [Figure 4]

[0016] 1 shows an example of a Physician Global Assessment (PGA) form as discussed in this disclosure, including examples, not to scale. [Figure 5A]

[0017] 1 shows the activity schedule for an unfractionated cohort, as disclosed in the Examples. [Figure 5B]

[0017] Figure 1 shows the activity schedule for an unfractionated cohort, as disclosed in the Examples. [Figure 5C]

[0017] Figure 7 shows the activity schedule for the unfractionated cohort as disclosed in the Examples. Note for Figure 7: On treatment days, all assessments must be performed prior to dosing unless otherwise noted. For participants at participating sites who provided written informed consent to participate in mobile care visits, mobile care may be used for assessments that do not require administration of study treatment or planned treatment changes. Mobile care is not permitted for screening, injection visits, unscheduled visits, early discontinuation visits, or in lieu of protocol-mandated hospitalization. ADA=anti-drug antibodies, BCR=B cell receptor, CD=cluster of differentiation, CMV=cytomegalovirus, CRP=C-reactive protein, CRS=cytokine release syndrome, CT=computed tomography, DSC=discontinuation, dsDNA=double-stranded DNA, EBV=Epstein-Barr virus; eCRF=electronic Case Report Form; HBsAg=hepatitis B surface antigen; HBsAb=hepatitis B surface antibody; HBcAb=total hepatitis B core antibody; HBV=hepatitis B virus; HCV=hepatitis C virus; LPI=last patient enrolled; NA=not applicable; NGS=next generation sequencing; OCS=oral corticosteroids; PGA=physician global assessment; PGI-S=patient global impression of severity; PK=pharmacokinetic; Pt=participant; QTcF=QT interval corrected using Fridericia's formula; RBR=Research Biosample Repository; RNP = ribonucleoprotein, SFU = safety follow-up, Sm = Smith antigen, TBNK = T, B, and natural killer cells, TCR = T cell receptor, WES = whole exome sequencing, WGS = whole genome sequencing, (x) = if clinically indicated or in specific cases in the respective footnotes. Notes for Figure 5: a Results of standard of care assessments within 28 days prior to Day 1, performed before obtaining informed consent, may be used; such assessments do not need to be repeated for screening. Patients who do not meet the entry criteria for this study may be eligible for three rescreening opportunities (for a total of four screens per patient) as described in 3.1.1 (Examples).b SFU will be performed at Month 12 and then every 6 months until B-cell recovery or end of study, whichever occurs first. c Participants who discontinue / withdraw early from the study will return to the clinic for a final participant early withdrawal visit. Reasons for participant discontinuation from the study are described in 4.6.2 (Examples). d Informed consent must be documented before study-specific screening procedures are performed and can be obtained more than 28 days prior to the start of study treatment. e Include respiratory rate, pulse (heart rate), systolic and diastolic blood pressure in a sitting position, and temperature at all visits, as well as oxygen saturation (pulse oximetry) at visits during the DLT assessment period. f Vital signs will be recorded pre-injection (within 30 minutes) and every 15 (± 10) minutes for 1 hour after mosunetuzumab SC injection. After this hour, vital signs will be recorded every 30 (± 15) minutes for 4 hours after injection. Vital signs should then be monitored every 4 (± 1) hours until discharge. g Includes evaluation of the head, eyes, ears, nose, throat, and cardiovascular, respiratory, neurological, gastrointestinal, musculoskeletal, and dermatological systems; genitourinary examination may be performed if clinically indicated. h Conduct targeted symptom-directed examinations at designated or clinically indicated times. At a minimum, targeted examinations include evaluation of the primary relevant systems (e.g., cardiovascular, respiratory, neurological). i If the mean QTcF is >500 ms and / or >60 ms longer than baseline at a given post-dose time point, another ECG should be recorded, ideally within the next 5 minutes, and ECG monitoring should continue until the QTcF has stabilized on two consecutive ECGs. If a PK sample is not scheduled at that time, an unscheduled PK sample should be obtained. j If a chest x-ray or chest CT has been performed within the past 3 months with no clinically significant abnormalities observed and no new pulmonary signs or symptoms, a chest x-ray is not required. k Dexamethasone 10 mg orally administered pre-dose, 24 (± 4) hours, and 48 (± 4) hours after mosunetuzumab injection.For non-hospitalized participants, compliance with oral dexamethasone prophylaxis should be monitored at clinic visits 24 (± 4) and 48 (± 4) hours after mosunetuzumab administration, at ambulatory care visits, or at telephone check-in. OCS administration should occur on the days dexamethasone is administered as premedication. l Medications (e.g., prescriptions, over-the-counter medications, vaccines, herbal or homeopathic remedies, dietary supplements) are used by patients in addition to protocol-mandated treatments from 7 days prior to study drug initiation until the final SFU or early study discontinuation visit. m After informed consent is obtained but before study drug initiation, only serious adverse events caused by protocol-mandated interventions will be reported. After study drug initiation, all adverse events will be reported until the final SFU visit. If the investigator becomes aware of any serious adverse events that appear to be related to previous exposure to the study drug after this period, the sponsor should be notified (see 5.6 (Example)). n The PGI-S will be self-administered before patients receive information about their disease status, before non-PRO assessments are performed, and before study treatment is administered. o PGAs will be completed by a clinician after the physical examination but before study treatment is administered. If a visit is performed by mobile nursing staff without a physician, PGAs will not be assessed at that visit. p Hematology includes complete blood count, including red blood cell count, hemoglobin, hematocrit, platelet count, white blood cell count, ANC, absolute lymphocyte count, and other cells. q For all serious infectious adverse events, a CBC with differentiation, quantitative immunoglobulins, and flow cytometry should be obtained within 1 week of onset. r Chemistry panel (serum or plasma) includes bicarbonate or total carbon dioxide (if considered standard of care for the area), sodium, potassium, chloride, glucose, BUN or urea, creatinine, total protein, albumin, phosphate, calcium, magnesium, total and direct bilirubin, ALP, ALT, AST, gamma-glutamyltransferase (GGT), uric acid, and LDH. s Choice of Sb testing (skin or blood tests) is determined according to local clinical practice.t Routine coagulation panel (aPTT, PT, and INR) should be taken at scheduled times. Fibrinogen should be added if monitoring for HLH and / or severe CRS events. u All women of childbearing potential will have a serum pregnancy test at screening. A urine pregnancy test should be performed prior to mosunetuzumab injection. If the urine pregnancy test is positive, it should be confirmed by a serum pregnancy test. v Includes dipstick (pH, specific gravity, glucose, protein, ketones, and blood) and microscopy (sediment, red blood cells, white blood cells, casts, crystals, epithelial cells, and bacteria). w HBV serology: HBsAg, HBsAb, and HBcAb for all participants. HCV serology: HCV antibody for all participants. Participants with negative HBsAg and HBsAb tests and positive HBcAb tests are ineligible. x HIV-1 and HIV-2 antibody testing. y EBV and CMV by quantitative PCR using peripheral blood samples. If local laboratory evaluation is not available for quantitative PCR detection of active EBV and CMV, samples may be analyzed at a central laboratory. z For eligibility screening only, if no eligibility testing has been documented within 12 months prior to screening, samples for ANA, anti-dsDNA, and anti-Sm should be collected and analyzed at a local laboratory. aa For eligibility screening, samples for B cell count (CD19+) should be collected and analyzed at a local laboratory. If testing is not available at a local laboratory, samples may be analyzed at a central laboratory. bb Autoantibodies include ANA, anti-dsDNA, anti-Sm, anti-SSA (Ro), anti-SSB (La), and anti-RNP. cc ​​Mumps, rubella, varicella, tetanus, influenza, and pneumococcus. dd Collect samples at 6 months only. ee If patient discontinues study before 6 months. ff CRS-associated biomarkers: may include but are not limited to IL-2, IL-8, IFN-γ, and TNF-α.gg Samples will be collected at month 12 only.hh A validated assay for mosunetuzumab will be used.ii Studies may include extraction of DNA and RNA for analysis of non-inherited BCR and TCR sequences and genomic profiling using NGS of a comprehensive gene panel. NGS methods do not include WGS or WES. [Figure 6A]

[0018] Showing schedule of activities: Fractionated cohorts. [Figure 6B]

[0018] Showing the schedule of activities: Fractionated cohorts. [Figure 6C]

[0018] Showing the schedule of activities: Segregated cohorts. Note: On treatment days, all assessments must occur prior to dosing unless otherwise noted. For participants at participating sites who provided written informed consent to participate in mobile care visits, mobile care may be used for evaluations that do not require administration of study treatment or planned treatment changes. Mobile care is not permitted for screening, injection visits, unscheduled visits, early discontinuation visits, or in lieu of protocol-mandated hospitalization. ADA=anti-drug antibodies, BCR=B cell receptor, CD=cluster of differentiation, CMV=cytomegalovirus, CRP=C-reactive protein, CRS=cytokine release syndrome, CT=computed tomography, DSC=discontinuation, dsDNA=double-stranded DNA, EBV=Epstein-Barr virus; eCRF=electronic Case Report Form; HBsAg=hepatitis B surface antigen; HBsAb=hepatitis B surface antibody; HBcAb=total hepatitis B core antibody; HBV=hepatitis B virus; HCV=hepatitis C virus; LPI=last patient enrolled; NA=not applicable; NGS=next generation sequencing; OCS=oral corticosteroids; PGA=physician global assessment; PGI-S=patient global impression of severity; PK=pharmacokinetic; Pt=participant; QTcF=QT interval corrected using Fridericia's formula; RBR=Research Biosample Repository; RNP = ribonucleoprotein, SFU = safety follow-up, Sm = Smith antigen, TBNK = T, B, and natural killer cells, TCR = T cell receptor, WES = whole exome sequencing, WGS = whole genome sequencing, (x) = if clinically indicated or in specific cases in the respective footnotes. Notes for Figure 6: a Results of standard of care assessments within 28 days prior to Day 1, performed before obtaining informed consent, may be used; such assessments do not need to be repeated for screening. Patients who do not meet the entry criteria for this study may be eligible for three rescreening opportunities (for a total of four screens per patient) as described in 3.1.1 (Examples).b SFU will be performed at Month 12 and then every 6 months until B-cell recovery or end of study, whichever occurs first. c Participants who discontinue / withdraw early from the study will return to the clinic for a final participant early withdrawal visit. Reasons for participant discontinuation from the study are described in 4.6.2 (Examples). d Informed consent must be documented before study-specific screening procedures are performed and can be obtained more than 28 days prior to the start of study treatment. e Include respiratory rate, pulse (heart rate), and systolic and diastolic blood pressure in a sitting position, and temperature at all visits, as well as oxygen saturation (pulse oximetry) at visits during the DLT assessment period. f Vital signs will be recorded (within 30 minutes) prior to injection and every 15 (± 10) minutes for 1 hour after mosunetuzumab SC injection. After this hour, vital signs will be recorded every 30 (± 15) minutes for 4 hours after injection. Vital signs should then be monitored every 4 (± 1) hours until discharge. For participants who tolerate the Day 1 injection without developing CRS, at the Day 8 injection, assess vital signs prior to injection (within 30 minutes) and every 60 minutes (± 30 minutes) for 4 hours after injection. For participants who experience CRS with the Day 1 injection, assess vital signs prior to injection (within 30 minutes) and every 30 minutes (± 15 minutes) for 4 hours after injection on Day 8. Vital signs should be monitored every 4 (± 1) hours thereafter until discharge. g Includes evaluation of the head, eyes, ears, nose, throat, and cardiovascular, respiratory, neurological, gastrointestinal, musculoskeletal, and dermatological systems; genitourinary examination may be performed if clinically indicated. h Conduct targeted symptom-directed examinations at designated or clinically indicated times. At a minimum, targeted examinations include evaluation of the primary relevant systems (e.g., cardiovascular, respiratory, neurological). i If at a particular post-dose time point, the mean QTcF is >500 ms and / or >60 ms longer than the baseline value, another ECG should be recorded, ideally within the next 5 minutes, and ECG monitoring should continue until the QTcF has stabilized on two consecutive ECGs. If a PK sample is not scheduled at that time, an unscheduled PK sample should be obtained.j Chest x-ray is not required if a chest x-ray or chest CT scan has been performed within the past 3 months and shows no clinically significant abnormalities and no new pulmonary signs or symptoms. k Dexamethasone 10 mg is given orally prior to dosing and 24 (± 4) and 48 (± 4) hours after each mosunetuzumab injection. For non-hospitalized participants, compliance with oral dexamethasone prophylaxis should be monitored at clinic visits, ambulatory care visits, or telephone check-in 24 (± 4) and 48 (± 4) hours after mosunetuzumab administration. OCS administration should occur on days when dexamethasone is administered as premedication. l Medications (e.g., prescriptions, over-the-counter medications, vaccines, herbal or homeopathic remedies, dietary supplements) are used by patients in addition to protocol-mandated treatment from 7 days prior to the start of study drug until the final SFU or early discontinuation visit. m After informed consent is obtained but before initiation of study drug, only serious adverse events caused by protocol-mandated interventions will be reported. After initiation of study drug, all adverse events will be reported until the final SFU visit. After this period, if the investigator becomes aware of any serious adverse events that appear to be related to previous exposure to the study drug, the sponsor should be notified (see 5.6 (Example)). n PGIs will be self-administered before patients receive information on disease status, before non-PRO assessments are performed, and before administration of study treatment. o PGAs will be completed by a clinician after the physical examination but before administration of study treatment. If the visit is performed by mobile nursing staff without a physician, PGAs will not be assessed at that visit. p Hematology includes complete blood count, including red blood cell count, hemoglobin, hematocrit, platelet count, white blood cell count, ANC, absolute lymphocyte count, and other cells. q For all serious infectious adverse events, CBC with differentiation, quantitative immunoglobulins, and flow cytometry should be obtained within 1 week of onset.r Chemistry panel (serum or plasma) includes bicarbonate or total carbon dioxide (if considered standard of care for the area), sodium, potassium, chloride, glucose, BUN or urea, creatinine, total protein, albumin, phosphate, calcium, magnesium, total and direct bilirubin, ALP, ALT, AST, gamma-glutamyltransferase (GGT), uric acid, and LDH. s Selection of Sb testing (skin or blood tests) will be determined according to local clinical practice. t Routine coagulation panel (aPTT, PT, and INR) should be taken at scheduled time points. Fibrinogen should be added if monitoring for HLH and / or severe CRS events. u All women of childbearing potential will have a serum pregnancy test at screening. A urine pregnancy test should be performed before each mosunetuzumab injection. If the urine pregnancy test is positive, it must be confirmed by a serum pregnancy test. v Includes dipstick (pH, specific gravity, glucose, protein, ketones, and blood) and microscopy (sediment, red blood cells, white blood cells, casts, crystals, epithelial cells, and bacteria). w HBV serology: HBsAg, HBsAb, and HBcAb for all participants. HCV serology: HCV antibody for all participants. Participants with negative HBsAg and HBsAb tests and positive HBcAb tests are ineligible. x HIV-1 and HIV-2 antibody testing. y EBV and CMV by quantitative PCR using peripheral blood samples. If local laboratory evaluation is not available for quantitative PCR detection of active EBV and CMV, samples may be analyzed at a central laboratory. z For eligibility screening only, if no eligibility testing has been documented within 12 months prior to screening, samples for ANA, anti-dsDNA, and anti-Sm should be collected and analyzed at a local laboratory. aa For eligibility screening, a sample for B cell count (CD19+) must be taken and analyzed by a local laboratory. If the test is not available at a local laboratory, it can be analyzed at a central laboratory. bb Samples are taken on day 1 only, not day 8.cc Autoantibodies include ANA, anti-dsDNA, anti-Sm, anti-SSA (Ro), anti-SSB (La), and anti-RNP. dd Mumps, rubella, varicella, tetanus, influenza, and pneumococcus. ee Samples collected at 6 months only. ff If patient discontinues study before 6 months. gg CRS-associated biomarkers: may include but are not limited to IL-2, IL-8, IFN-γ, TNF-α. hh Samples collected at 12 months only. ii Use a validated assay for mosnetuzumab. jj Studies may include DNA and RNA extraction for analysis of non-inherited BCR and TCR sequences and genomic profiling using NGS of a comprehensive gene panel. NGS methods do not include WGS or WES. [Figure 7]

[0019] The 2019 European League Against Rheumatism (EULAR) / American College of Rheumatology (ACR) classification criteria for systemic lupus erythematosus are shown. [Figure 8]

[0020] 1 shows B cell depletion in fractionated cohorts as disclosed in the Examples. The lower limit of quantification was ≦0.441 cells / μL. [Figure 9]

[0021] 1 shows anti-double stranded (dsDNA) antibody (IgG) levels in patients treated according to the examples. [Figure 10]

[0022] 1 shows a summary of safety dates related to transient lymphopenia associated with mosunetuzumab in patients treated according to the Examples. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] I. General Techniques

[0023] The techniques and procedures described or referenced herein are generally well understood and commonly employed by those of skill in the art using conventional methodologies, such as, for example, the widely used methodologies described in the following documents: Sambrook et al., Molecular Cloning: A Laboratory Manual 3d edition (2001) Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY; Current Protocols in Molecular Biology (FMA Usubel, et al. eds., (2003)); the series Methods in Enzymology (Academic Press, Inc.): PCR 2: A Practical Approach (MJ MacPherson, BD Hames and GR Taylor eds. (1995)), Harlow and Lane, eds. (1988) Antibodies, A Laboratory Manual, and Animal Cell Culture (RI Freshney, ed. (1987)); Oligonucleotide Synthesis (MJ Gait, ed., 1984); Methods in Molecular Biology, Humana Press; Cell Biology: A Laboratory Notebook (JECellis, ed., 1998) Academic Press; Animal Cell Culture (RIFreshney), ed., 1987); Introduction to Cell and Tissue Culture (JP Mather and PE Roberts, 1998) Plenum Press; DG Newell, eds., 1993-8) J. Wiley and Sons; Handbook of Experimental Immunology (DM3)), the series Methods in Enzymology (Academic Press, Inc.): Weir and CC Blackwell, eds.); Gene Transfer Vectors for Mammalian Cells (JM. Miller and MPCalos, eds., 1987); PCR: The Polymerase Chain Reaction, (Mullis et al., eds., 1994); Current Protocols in Immunology (JEColigan et al. al., eds., 1991); Short Protocols in Molecular Biology (Wiley and Sons, 1999); Immunobiology (CA Janeway and P. Travers, 1997); Antibodies (P. Finch, 1997); Antibodies: A Practical Approach (D. Catty., ed., IRL Press, 1988-1989); Monoclonal Antibodies: A Practical Approach (P. Shepherd and C. Dean, eds., Oxford University Press, 2000); Using Antibodies: A Laboratory Manual (E. Harlow and D. Lane (Cold Spring Harbor Laboratory Press, 1999); The Antibodies (M. Zanetti and JD Capra, eds., Harwood Academic Publishers, 1995); and Cancer: Principles and Practice of Oncology (VTDeVita et al., eds., JBLippincott Company, 1993).

[0015] II. Definition

[0024] It is understood that the aspects and embodiments of the invention described herein include "comprising," "consisting," and "consisting essentially of" aspects and embodiments.

[0016]

[0025] As used herein, the singular forms "a," "an," and "the" include plurals unless otherwise indicated.

[0017]

[0026] As used herein, the term "about" refers to the normal range of error for the respective value, which is readily understood by one of ordinary skill in the art. Reference herein to a value or parameter preceded by "about" includes (and describes) embodiments that are directed to that value or parameter itself.

[0018]

[0027] A "disorder" is any condition that would benefit from treatment, including, but not limited to, chronic and acute disorders or diseases, including pathological conditions that predispose a mammal to the disorder in question.

[0019]

[0028] Systemic lupus erythematosus refers to an autoimmune rheumatic disease that occurs primarily in women of childbearing age. Systemic lupus erythematosus is characterized by multiorgan involvement and immunological abnormalities, including B-cell and T-cell dysfunction. Much of the tissue damage is thought to result from autoantibody formation and immune complex deposition, but the underlying cause is unknown. Lupus nephritis is the most common target organ manifestation. "SLE" refers to systemic lupus erythematosus.

[0020]

[0029] "Lupus-related neuropsychiatric disorders" include, but are not limited to, meningitis, retinitis, cerebral vasculitis, myelopathy, demyelinating syndromes, acute confusional states, psychosis, acute stroke or stroke syndromes, cranial neuropathy, status epilepticus or seizures, cerebellar ataxia, and multiple mononeuritis.

[0021]

[0030] "Overlap syndrome" refers to inflammatory rheumatic conditions. The most common overlap syndromes are rheumatoid arthritis, scleroderma, lupus, and myositis. "Mixed connective tissue disease" refers to a condition of overlap syndrome defined by anti-U1 ribonucleoprotein autoimmunity with features of at least two of the following conditions: rheumatoid arthritis, lupus, scleroderma, and myositis.

[0022]

[0031] "Antiphospholipid overlap syndrome" refers to an autoimmune disease in which anti-autophospholipid antibodies attack phospholipids. Symptoms vary and can include blood clots, miscarriages, rashes, chronic headaches, dementia, and seizures. "Severe antiphospholipid overlap syndrome" refers to antiphospholipid overlap syndrome that is difficult to treat with conventional therapies. "Fulminant antiphospholipid overlap syndrome" refers to a rare form of antiphospholipid overlap syndrome in which multiple blood clots form throughout the body in a short period of time, often leading to organ failure if untreated. Antiphospholipid overlap syndrome is often treated with anticoagulant therapy.

[0023]

[0032] "Anticoagulant therapy" may include, for example, (oral) vitamin K antagonists (e.g., warfarin) and direct oral anticoagulants (such as rivaroxaban, apixaban, and dabigatran).

[0024]

[0033] "CD19" refers to "cluster of differentiation 19," which is expressed throughout the B lineage from pro-B cells to mature B cells, is not shed, is uniformly expressed in all lymphoma cells, and is not present in stem cells. "Anti-CD19 antibody therapy" refers to a therapy in which an anti-CD19 antibody is administered to a patient. One example of such a treatment is the administration of blinatumab.

[0025]

[0034] "Janus kinase inhibitor" refers to a compound that inhibits the activity of Janus kinases ("JAK"), such as JAK1, JAK2, JAK3, and TYK2 (tyrosine kinase 2). Common Janus kinase inhibitors include baricitinib, tofacitinib, upadacitinib, filgotinib, ibrutinib, or fenebrutinib.

[0026]

[0035] "Bruton's tyrosine kinase inhibitors" refers to inhibitors of Bruton's tyrosine kinase activity, such as ibrutinib, acalabrutinib, and zanubrutinib.

[0027]

[0036] As used herein, "treatment" (and grammatical variations thereof, such as "treat" or "treating") refers to a clinical intervention that attempts to alter the natural course of the patient being treated, and can be performed prophylactically or during the course of clinical pathology. Desirable effects of treatment include, but are not limited to, prevention of disease onset or recurrence, alleviation of symptoms, diminishment of any direct or indirect pathological consequences of the disease, slowing the rate of disease progression, amelioration or improvement of the disease state, and remission or improvement of prognosis. In some embodiments, the antibodies are used to delay the onset of the disease or slow the progression of the disease.

[0028]

[0037] As used herein, "delaying the progression" of a disease or disorder refers to putting off, preventing, delaying, impeding, stabilizing, and / or postponing the onset of a disease or disorder (e.g., systemic lupus erythematosus). This delay can be of varying lengths of time depending on the history of the disease and / or the patient being treated. As will be apparent to one of skill in the art, a sufficient or significant delay can, in effect, encompass prevention, in that the patient does not develop the disease.

[0029]

[0038] By "reduce" or "inhibit" is meant the ability to cause an overall reduction, for example, of 20%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 85%, 90%, 95% or more. For clarity, the term also includes reduction to zero (or below the detection limit of the analytical method), i.e., complete resolution or elimination. In certain embodiments, reduction or inhibition refers to a reduction or inhibition of undesirable events, such as cytokine-driven toxicity (e.g., cytokine release syndrome (CRS)), infusion-related reactions (IRR), macrophage activation syndrome (MAS), neurotoxicity, severe tumor lysis syndrome (TLS), neutropenia, thrombocytopenia, elevated liver enzymes, and / or central nervous system (CNS) toxicity following treatment with an anti-CD20 / anti-CD3 bispecific antibody. In other embodiments, reducing or inhibiting may refer to antibody effector functions mediated by the antibody Fc region, specifically including complement dependent cytotoxicity (CDC), antibody dependent cellular cytotoxicity (ADCC), and antibody dependent cellular phagocytosis (ADCP). In other embodiments, reducing or inhibiting may refer to symptoms of systemic lupus erythematosus.

[0030]

[0039] As used herein, "administering" refers to a method of providing a dosage of a compound (e.g., a bispecific antibody) or composition (e.g., a pharmaceutical composition, e.g., a pharmaceutical composition comprising a bispecific antibody) to a patient. Compounds and / or compositions utilized in the methods described herein may be administered intravenously (e.g., by intravenous infusion).

[0031] A "fixed dose" or "flat dose" refers to a dose of a therapeutic agent (e.g., a bispecific antibody) described herein that is administered to a patient without regard to the patient's weight or body surface area (BSA). Thus, the fixed dose or flat dose is expressed as a mg / kg dose or a mg / m 2 It is not specified as a dose, but rather as an absolute amount (eg, mg) of therapeutic agent.

[0032]

[0041] A "stable dose" refers to a constant dose of a drug for a period of time, e.g., 40 mg / day for 7 days. That period can be as short as a few days or as long as many years. The opposite is an "adjustable dose."

[0033]

[0042] A "patient" is a mammal. Mammals include, but are not limited to, primates (e.g., humans and non-human primates, such as monkeys), livestock (e.g., cows, sheep, cats, dogs and horses), rabbits, and rodents (e.g., mice and rats). In certain embodiments, the patient or subjects are human.

[0034]

[0043] "Patient response" or "response" refers to a response that may be assessed using any endpoint that indicates benefit to the patient, including, but not limited to, some inhibition of disease progression. Response to a systemic lupus erythematosus therapy or treatment may be assessed, for example, using the following: Patient Global Impression of Severity (PGI-S), Physician Global Assessment (PGA), -Changes in antinuclear antibody (ANA) titers, Changes in the titer of anti-double-stranded DNA (dsDNA) antibodies, Alterations in complement C3, and / or - Alterations in complement C4.

[0035]

[0044] "Patient Global Impression of Severity" or "PGI-S" refers to a single-item question that asks patients how they rate their overall lupus severity over the past week. The form asks, "Please select the response that best describes the severity of your lupus over the past week." There are five response categories: (1) none, (2) mild, (3) moderate, (4) severe, and (5) very severe. An example is shown in Figure 3.

[0036]

[0045] "Physician Global Assessment" or "PGA" refers to an assessment instrument used by physicians in assessing patients for their systemic lupus erythematosus. The form asks, "Please answer the following questions by placing a vertical mark on the line," where the "lines" represent a scale subdivided from none (0) to 3 (severe). The question is, "On the line below, where would you rate the subject's SLE over the past 28 days?" An example is shown in Figure 4.

[0037]

[0046] "Antinuclear antibodies" (ANA) refer to a diverse group of autoantibodies that recognize nuclear macromolecules and their complexes. ANA are important biomarkers in the evaluation of rheumatic diseases such as systemic lupus erythematosus.

[0038]

[0047] The term "anti-double-stranded DNA (dsDNA) antibody" refers to a group of autoantibodies that recognize double-stranded DNA (dsDNA).

[0039]

[0048] An "effective amount" is at least the minimum concentration required to achieve a measurable improvement or prevention of a particular disorder. The effective amount herein may vary depending on factors such as the disease state, age, sex, and weight of the patient, and the ability of the antibody to elicit a desired response in an individual. An effective amount is also an amount in which the therapeutically beneficial effects outweigh any toxic or adverse effects of the treatment. In the case of prophylactic use, beneficial or desired results include results such as eliminating or reducing the risk of the disease, reducing the severity of the disease, or delaying the onset of the disease, including the biochemical, histological, and / or behavioral symptoms of the disease, its complications, and intermediate pathological phenotypes that appear during the development of the disease. In the case of therapeutic use, beneficial or desired results include clinical results such as reducing one or more symptoms caused by the disease, improving the quality of life of the person suffering from the disease, reducing the dose of other drugs required to treat the disease, enhancing the effect of another drug (e.g., by targeting), delaying the progression of the disease, and / or prolonging survival. In the case of lupus nephritis, an effective amount of the drug may be effective and / or provide some relief to one or more symptoms associated with the disease. An effective amount may be administered in one or more doses. In the present invention, an effective amount of a drug, compound, or pharmaceutical composition is an amount sufficient to directly or indirectly achieve a prophylactic or therapeutic treatment. As understood in the clinical field, an effective amount of a drug, compound, or pharmaceutical composition may or may not be achieved in conjunction with another drug, compound, or pharmaceutical composition. Thus, an "effective amount" may be considered in relation to administering one or more therapeutic agents, and a single agent may be considered to be administered in an effective amount when a desired result can or is achieved in combination with one or more other agents.

[0040]

[0049] An "effective subject response" or patient "responsiveness" to treatment with a pharmaceutical agent and similar words refer to a clinical or therapeutic benefit conferred on a patient at risk for or suffering from a disease or disorder, such as systemic lupus erythematosus. In one embodiment, such benefit includes the reduction or elimination of symptoms of systemic lupus erythematosus, or a change in a biomarker associated with systemic lupus erythematosus toward or achieving a healthy value.

[0041]

[0050] A patient who "does not respond effectively to treatment" refers to a patient whose signs or symptoms of systemic lupus erythematosus do not improve.

[0042] The term "antibody" herein is used in the broadest sense and encompasses a variety of antibody structures, including, but not limited to, monoclonal antibodies, polyclonal antibodies, multispecific antibodies (e.g., bispecific antibodies), and antibody fragments, so long as they exhibit the desired antigen-binding activity.

[0043]

[0052] "Antibody fragment" refers to a molecule other than an intact antibody that contains a portion of an intact antibody that binds to the antigen to which the intact antibody binds. Examples of antibody fragments include, but are not limited to, Fv, Fab, Fab', Fab'-SH, F(ab')2; diabodies; linear antibodies; single-chain antibody molecules (e.g., scFv); and multispecific antibodies formed from antibody fragments.

[0044]

[0053] The terms "full length antibody," "intact antibody," and "whole antibody" are used interchangeably herein to refer to an antibody having a structure substantially similar to a native antibody structure or an antibody having a heavy chain that includes an Fc region as defined herein.

[0045]

[0054] "Binding domain" refers to a portion of a compound or molecule that specifically binds to a target epitope, antigen, ligand, or receptor. Binding domains include, but are not limited to, antibodies (e.g., monoclonal, polyclonal, recombinant, humanized, and chimeric antibodies), antibody fragments or portions thereof (e.g., Fab fragments, Fab'2, scFv antibodies, SMIPs, domain antibodies, diabodies, minibodies, scFv-Fc, affibodies, nanobodies, and VH and / or VL domains of antibodies), receptors, ligands, aptamers, and other molecules with identified binding partners.

[0046]

[0055] The term "Fc region" is used herein to define a C-terminal region of an immunoglobulin heavy chain that contains at least a portion of a constant region. This term includes native sequence Fc regions and variant Fc regions. In one embodiment, a human IgG heavy chain Fc region extends from Cys226, or from Pro230, to the carboxyl terminus of the heavy chain. However, the C-terminal lysine (Lys447) of the Fc region may or may not be present. Unless otherwise specified herein, the numbering of amino acid residues in an Fc region or constant region is according to the EU numbering system, also referred to as the EU index, as described in Kabat et al. (1991).

[0047]

[0056] The "class" of an antibody refers to the type of constant domain or region carried by its heavy chain. There are five major classes of antibodies, namely IgA, IgD, IgE, IgG, and IgM, and several of these can be further divided into subclasses (isotypes), e.g., IgG1, IgG2, IgG3, IgG4, IgA1, and IgA2. The heavy chain constant domains that correspond to the different classes of immunoglobulins are called a, d, e, g, and m, respectively.

[0048]

[0057] The term IgG "isotype" or "subclass" as used herein means any of the subclasses of immunoglobulins defined by the chemical and antigenic properties of their constant regions.

[0049]

[0058] "Framework" or "FR" refers to variable domain residues other than hypervariable region (HVR) residues. The FR of a variable domain generally consists of four FR domains: FR1, FR2, FR3, and FR4. Thus, the HVR and FR sequences generally appear in the following order in a VH (or VL): FR1-H1(L1)-FR2-H2(L2)-FR3-H3(L3)-FR4.

[0050]

[0059] A "human consensus framework" is a framework that represents the most commonly occurring amino acid residues in a selection of human immunoglobulin VL or VH framework sequences. Generally, the selection of human immunoglobulin VL or VH sequences is from a subgroup of variable domain sequences. Generally, the subgroup of sequences is a subgroup as in Kabat et al., Sequences of Proteins of Immunological Interest, Fifth Edition, NIH Publication 91-3242, Bethesda MD (1991), vols. 1-3. In one embodiment, for VL, the subgroup is subgroup kappa I in Kabat et al. (see above). In one embodiment, for VH, the subgroup is subgroup III in Kabat et al. (see above).

[0051]

[0060] For purposes herein, an "acceptor human framework" is a framework that comprises the amino acid sequence of a light chain variable domain (VL) framework or a heavy chain variable domain (VH) framework derived from a human immunoglobulin framework or a human consensus framework, as defined below. An acceptor human framework "derived from" a human immunoglobulin framework or a human consensus framework may comprise its identical amino acid sequence or may contain amino acid sequence changes. In some embodiments, the number of amino acid changes is 10 or less, 9 or less, 8 or less, 7 or less, 6 or less, 5 or less, 4 or less, 3 or less, or 2 or less. In some embodiments, the VL acceptor human framework is identical in sequence to the VL human immunoglobulin framework sequence or the human consensus framework sequence.

[0052]

[0061] A "humanized" antibody refers to a chimeric antibody that comprises amino acid residues from non-human HVRs and amino acid residues from human FRs. In certain embodiments, a humanized antibody comprises substantially all of at least one, and typically two, variable domains, in which all or substantially all of the HVRs (e.g., CDRs) correspond to a non-human antibody and all or substantially all of the FRs correspond to a human antibody. A humanized antibody may optionally comprise at least a portion of an antibody constant region derived from a human antibody. A "humanized form" of an antibody, e.g., a non-human antibody, refers to an antibody that has undergone humanization.

[0053]

[0062] A "human antibody" is an antibody having an amino acid sequence that corresponds to the amino acid sequence of an antibody produced by a human or human cell, or of an antibody derived from a non-human source utilizing a human antibody repertoire, or to a sequence encoding another human antibody. This definition of a human antibody specifically excludes humanized antibodies that contain non-human antigen-binding residues. Human antibodies can be generated using a variety of techniques known in the art, including phage display libraries. Hoogenboom and Winter, J. Mol. Biol., 227:381 (1991); Marks et al., J. Mol. Biol., 222:581 (1991). Human monoclonal antibodies can also be prepared using the methods described in Cole et al., Monoclonal Antibodies and Cancer Therapy, Alan R. Liss, p.77 (1985); Boerner et al., J. Immunol., 147(1):86-95 (1991). See also van Dijk and van de Winkel, Curr. Opin. Pharmacol., 5:368-74 (2001). Human antibodies can be prepared by administering antigen to transgenic animals, e.g., immunized Xenomouse, which have been modified to produce such antibodies in response to antigen challenge, but whose endogenous loci have been invalidated (e.g., XENOMOUSE TM(See U.S. Patent Nos. 6,075,181 and 6,150,584 for related technology.) See also, e.g., Li et al., Proc. Natl. Acad. Sci. USA, 103:3557-3562 (2006) for human antibodies produced by human B cell hybridoma technology.

[0054]

[0063] The term "variable region" or "variable domain" refers to the domain of an antibody heavy or light chain that is involved in binding the antibody to an antigen. The heavy and light chain variable domains (VH and VL, respectively) of natural antibodies generally have a similar structure, and each domain contains four conserved framework regions (FR) and three hypervariable regions (HVR). (See, for example, Kindt et al. Kuby Immunology, 6 th ed., W. H. Freeman and Co., page 91 (2007). A single VH or VL domain may be sufficient to confer antigen-binding specificity. Antibodies that bind to a specific antigen can be isolated by using a VH or VL domain from an antibody that binds the antigen to screen a library of complementary VL or VH domains, respectively. See, e.g., Portolano et al., J. Immunol. 150:880-887 (1993); Clarkson et al., Nature 352:624-628 (1991).

[0055]

[0064] The term "hypervariable region" or "HVR" as used herein refers to each of the regions of an antibody variable domain that are hypervariable in sequence ("complementarity determining regions" or "CDRs") and / or that structurally form defined loops ("hypervariable loops") and / or contain residues that contact the antigen ("antigen contacts"). Generally, antibodies contain six HVRs, three in the VH (H1, H2, H3) and three in the VL (L1, L2, L3). Exemplary HVRs herein include the following: 1. The hypervariable loops occurring at amino acid residues 26-32 (L1), 50-52 (L2), 91-96 (L3), 26-32 (H1), 53-55 (H2), and 96-101 (H3) (Chothia and Lesk, J. Mol. Biol. 196:901-917 (1987)); 2. CDRs occurring at amino acid residues 24-34 (L1), 50-56 (L2), 89-97 (L3), 31-35b (H1), 50-65 (H2), and 95-102 (H3) (Kabat et al., Sequences of Proteins of Immunological Interest, 5th Ed. Public Health Service, National Institutes of Health, Bethesda, MD (1991)); 3. Antigen contacts occurring at amino acid residues 27c-36 (L1), 46-55 (L2), 89-96 (L3), 30-35b (H1), 47-58 (H2), and 93-101 (H3) (MacCallum et al. J. Mol. Biol. 262:732-745 (1996)); and 4. Combinations of (1), (2), and / or (3), comprising HVR amino acid residues 46-56 (L2), 47-56 (L2), 48-56 (L2), 49-56 (L2), 26-35 (H1), 26-35b (H1), 49-65 (H2), 93-102 (H3), and 94-102 (H3).

[0056]

[0065] Unless otherwise indicated, HVR residues and other residues in the variable domain (e.g., FR residues) are numbered herein according to Kabat et al., supra.

[0057]

[0066] The term "isolated antibody", as used to describe the various antibodies disclosed herein, refers to an antibody that has been identified and separated and / or recovered from the cell or cell culture in which it is expressed. Contaminant components of its natural environment are materials that would typically interfere with diagnostic or therapeutic uses of the polypeptide and may include enzymes, hormones, and other proteinaceous or non-proteinaceous solutes. In some embodiments, the antibody is purified to greater than 95% or greater than 99% purity, as determined, for example, by electrophoresis (e.g., SDS-PAGE, isoelectric focusing (IEF), capillary electrophoresis) or chromatography (e.g., ion exchange or reverse-phase HPLC). For a review of methods for assessing antibody purity, see, e.g., Flatman et al., J. Chromatogr. B 848:79-87 (2007). In a preferred embodiment, the antibody is purified (1) sufficiently to obtain at least 15 residues of N-terminal or internal amino acid sequence using a spinning cup sequenator, or (2) to homogeneity by SDS-PAGE under non-reducing or reducing conditions using Coomassie blue or, preferably, silver stain. Isolated antibody includes antibody in situ, within recombinant cells, since at least one component of the polypeptide's natural environment will not be present. Ordinarily, however, an isolated polypeptide will be prepared by at least one purification step.

[0058]

[0067] The term "monoclonal antibody" as used herein refers to an antibody obtained from a population of substantially homogeneous antibodies, i.e., the patient antibodies comprising the population are identical and / or bind to the same epitope, with the exception of possible variant antibodies that contain, for example, naturally occurring mutations or arise during the production of the monoclonal antibody preparation, such variants being generally present in minor amounts. In contrast to polyclonal antibody preparations, which typically contain different antibodies against different determinants (epitopes), each monoclonal antibody of a monoclonal antibody preparation is directed against a single determinant on the antigen. Thus, the modifier "monoclonal" indicates the character of the antibody as being obtained from a substantially homogeneous population of antibodies, and should not be construed as requiring production of the antibody by any particular method. For example, monoclonal antibodies used in accordance with the present invention may be produced by a variety of techniques, including, but not limited to, hybridoma methods, recombinant DNA methods, phage display methods, and methods utilizing transgenic animals containing all or part of the human immunoglobulin loci, and such methods and other exemplary methods for producing monoclonal antibodies are described herein.

[0059]

[0068] "Affinity" refers to the strength of the sum of non-covalent interactions between a single binding site of a molecule (e.g., an antibody) and its binding partner (e.g., an antigen). Unless otherwise indicated, as used herein, "binding affinity" refers to the intrinsic binding affinity that reflects a 1:1 interaction between members of a binding pair (e.g., an antibody and an antigen). The affinity of a molecule X for its partner Y can generally be represented by a dissociation constant (Kd). Affinity can be measured by methods common in the art, including those described herein. Specific illustrative and exemplary embodiments for measuring binding affinity are described below.

[0060]

[0069] An "affinity matured" antibody refers to an antibody that has one or more alterations in one or more hypervariable regions (HVRs), which improve the affinity of the antibody for antigen, compared to a parent antibody that does not possess the alterations.

[0061]

[0070] The terms "anti-CD3 antibody" and "antibody that binds to CD3" refer to an antibody that is capable of binding to CD3 with sufficient affinity such that the antibody is useful as a diagnostic and / or therapeutic agent in targeting CD3. In one embodiment, the extent of binding of an anti-CD3 antibody to unrelated non-CD3 proteins is less than about 10% of the binding of the antibody to CD3, as measured, for example, by radioimmunoassay (RIA). In certain embodiments, an antibody that binds to CD3 has an affinity of 1 μM or less, 100 nM or less, 10 nM or less, 1 nM or less, 0.1 nM or less, 0.01 nM or less, or 0.001 nM or less (e.g., 10 -8 M or less, e.g. 10 -8 M~10 -13 M, for example 10 -9 M~10 -13 Dissociation constant (K D In certain embodiments, the anti-CD3 antibody binds to an epitope of CD3 that is conserved among CD3 of different species.

[0062]

[0071] The term "cluster of differentiation 3" or "CD3", as used herein, unless otherwise indicated, refers to any native CD3 from any vertebrate source, including mammals such as primates (e.g., humans) and rodents (e.g., mice and rats), including, for example, the CD3ε, CD3γ, CD3α, and CD3β chains. The term encompasses "full-length" native CD3 (e.g., native or unmodified CD3ε or CD3γ), as well as any form of CD3 resulting from processing within a cell. The term also encompasses naturally occurring variants of CD3, including, for example, splice variants or allelic variants. CD3 includes, for example, the human CD3ε protein, which is 207 amino acids long (NCBI Reference SEQ ID NO: NP_000724), and the human CD3γ protein, which is 182 amino acids long (NCBI Reference SEQ ID NO: NP_000064).

[0063]

[0072] The terms "anti-CD20 antibody" and "antibody that binds to CD20" refer to an antibody that is capable of binding to CD20 with sufficient affinity such that the antibody is useful as a diagnostic and / or therapeutic agent in targeting CD20. In one embodiment, the binding of an anti-CD20 antibody to an unrelated, non-CD20 protein is less than about 10% of the binding of the antibody to CD20, as measured, for example, by radioimmunoassay (RIA). In certain embodiments, an antibody that binds to CD20 has an affinity of 1 μM or less, 100 nM or less, 10 nM or less, 1 nM or less, 0.1 nM or less, 0.01 nM or less, or 0.001 nM or less (e.g., 10 -8 M or less, e.g. 10 -8 M~10 -13 M, for example 10 -9 M~10 -13 M) in which the antibody binds to an epitope of CD20 that is conserved among CD20 from different species.

[0064]

[0073] The term "cluster of differentiation 20" or "CD20", as used herein, unless otherwise indicated, refers to any native CD20 from any vertebrate source, including mammals such as primates (e.g., humans) and rodents (e.g., mice and rats). The term encompasses "full-length" unprocessed, unprocessed CD20, as well as any form of CD20 resulting from processing within a cell. The term also encompasses naturally occurring variants of CD20, including, for example, splice variants or allelic variants. CD20 includes, for example, the human CD20 protein (see, for example, NCBI Reference SEQ ID NOs. NP_068769.2 and NP_690605.1), which may be produced, for example, from a variant mRNA transcript that is, for example, 297 amino acids long and lacks, for example, a portion of the 5' UTR (see, for example, NCBI Reference SEQ ID NO. NM_021950.3), or a longer mutant mRNA transcript (see, for example, NCBI Reference SEQ ID NO. NM_152866.2).

[0065]

[0074] "Anti-CD20 monoclonal antibody therapy" refers to the administration of anti-CD20 monoclonal antibodies to a patient. Examples include obinutuzumab, rituximab, ocrelizumab, and ofatumumab.

[0066]

[0075] The terms "anti-CD20 / anti-CD3 bispecific antibody", "bispecific anti-CD20 / anti-CD3 antibody" and "antibody that binds CD20 and CD3" or variants thereof refer to a multispecific antibody (e.g., a bispecific antibody) that is capable of binding to CD20 and CD3 with sufficient affinity such that the antibody is useful as a diagnostic and / or therapeutic agent in targeting CD20 and / or CD3. In one embodiment, the degree of binding of a bispecific antibody that binds CD20 and CD3 to unrelated non-CD3 and / or non-CD20 proteins is less than about 10% of the binding of the antibody to CD3 and / or CD20, as measured, for example, by radioimmunoassay (RIA). In certain embodiments, a bispecific antibody that binds CD20 and CD3 has an affinity of 1 μM or less, 100 nM or less, 10 nM or less, 1 nM or less, 0.1 nM or less, 0.01 nM or less, or 0.001 nM or less (e.g., 10 -8 M or less, e.g. 10 -8 M~10 -13 M, for example 10 -9 M~10 -13 In certain embodiments, the bispecific antibody that binds CD20 and CD3 binds to an epitope of CD3 that is conserved among CD3 from different species and / or an epitope of CD20 that is conserved among CD20 from different species. In one embodiment, the bispecific antibody binds monovalently to CD20 and monovalently to CD3. In one embodiment, the bispecific antibody that binds CD20 and CD3 is mosunetuzumab.

[0067]

[0076] As used herein, the term "mosunetuzumab" refers to an anti-CD20 / anti-CD3 bispecific antibody having the International Nonproprietary Name (INN) List 117 (WHO Drug Information, Vol. 31, No. 2, 2017, p. 303) or CAS Registry Number 1905409-39-3.

[0068]

[0077] As used herein, the terms "bind", "specifically bind to", or "specific for" refer to a measurable and reproducible interaction, such as binding between a target and an antibody, that is determinative of the presence of a target in the presence of a heterogeneous population of molecules, including biomolecules. For example, an antibody that specifically binds to a target (which may be an epitope) is an antibody that binds to this target with higher affinity, avidity, more readily, and / or with longer duration than it binds to other targets. In one embodiment, the degree of binding of the antibody to an unrelated target is less than about 10% of the binding of the antibody to the target, as measured, for example, by radioimmunoassay (RIA). In certain embodiments, an antibody that specifically binds to a target has a dissociation constant (K) of 1 μM or less, 100 nM or less, 10 nM or less, 1 nM or less, or 0.1 nM or less. D In certain embodiments, the antibody specifically binds to an epitope on a protein that is conserved among proteins from different species. In other embodiments, specific binding can include, but is not required to include, exclusive binding. The term as used herein includes, for example, -4 M or less, or 10 -5 M or less, or 10 -6 M or less, or 10 -7 M or less, or 10 -8 M or less, or 10 -9 M or less, or 10 -10 M or less, or 10 -11 M or less, or 10 -12 K against targets smaller than M D , or 10 -4 M~10 -6 M or 10 -6 M~10 -10 M or 10 -7M~10 -9 K in the M range D As will be appreciated by those of skill in the art, affinity and K D The values ​​are inversely correlated. A high affinity for the antigen corresponds to a low K D In one embodiment, the term "specific binding" refers to binding when a molecule binds to a particular polypeptide or an epitope on a particular polypeptide without substantially binding to any other polypeptides or polypeptide epitopes.

[0069]

[0078] "Percent (%) amino acid sequence identity" with respect to a reference polypeptide sequence is defined as the percentage of amino acid residues in a candidate sequence that are identical to the amino acid residues in the reference polypeptide sequence after sequence alignment and, if necessary, introduction of gaps to achieve the maximum percent sequence identity, without considering any conservative substitutions as part of the sequence identity. Alignment to determine percent amino acid sequence identity can be accomplished using a variety of methods within the skill of the art, such as publicly available computer software, such as BLAST, BLAST-2, ALIGN, or MEGALIGN® (DNASTAR®) software. Those skilled in the art can determine appropriate parameters for sequence alignment, including any algorithms required to achieve maximum alignment over the entire length of the sequences being compared. However, for purposes herein, percent amino acid sequence identity values ​​are generated using the sequence comparison computer program ALIGN-2. The ALIGN-2 sequence comparison computer program was written by Genentech, Inc., and the source code, together with user documentation, has been filed with the U.S. Copyright Office, Washington DC, 20559, where it is registered under U.S. Copyright Registration No. TXU510087. The ALIGN-2 program is publicly available from Genentech, Inc., South San Francisco, California, or may be compiled from its source code. The ALIGN-2 program should be compiled for use on UNIX operating systems, including digital UNIX V4.0D. All sequence comparison parameters are set by the ALIGN-2 program and do not vary.

[0070]

[0079] In situations where ALIGN-2 is used for amino acid sequence comparisons, the % amino acid sequence identity of a given amino acid sequence A to, with, or relative to a given amino acid sequence B (alternatively, it may be written as a given amino acid sequence A having or containing a particular % amino acid sequence identity to, with, or relative to a given amino acid sequence B) is calculated as follows: 100 x fraction X / Y where X is the number of amino acid residues scored as identical by the sequence alignment program ALIGN-2 in that program's alignment of A and B, and Y is the total number of amino acid residues in B. It will be understood that if the length of amino acid sequence A is not equal to the length of amino acid sequence B, then the % amino acid sequence identity of A to B will not be equal to the % amino acid sequence identity of B to A. Unless otherwise specified, all % amino acid sequence identity values ​​used herein are obtained as described in the immediately preceding paragraph using the ALIGN-2 computer program.

[0071]

[0080] The term "pharmaceutical formulation" refers to a preparation that is in a form such that the biological activity of the active ingredient contained in the preparation is effective and does not contain any additional components that are unacceptably toxic to the patient to whom the formulation will be administered.

[0072]

[0081] "Pharmaceutically acceptable carrier" refers to an ingredient in a pharmaceutical formulation, other than an active ingredient, that is non-toxic to a patient. Pharmaceutically acceptable carriers include, but are not limited to, buffers, additives, stabilizers, or preservatives.

[0073]

[0082] The term "package insert" is used to refer to instructions typically included in commercial packaging of a therapeutic product that contain information about the indications, usage, dosage, administration, concomitant therapy, contraindications and / or warnings for the use of such therapeutic product.

[0074] III. Treatment method

[0083] Provided herein is a method of treating a patient with systemic lupus erythematosus comprising administering a regimen of mosunetuzumab.

[0075] A. Characteristics of systemic lupus erythematosus

[0084] Systemic lupus erythematosus is an unpredictable disease characterized by alternating periods of remission and a wide variety of clinical manifestations that can affect any organ (Fortuna G, Brennan MT. Systemic lupus erythematosus: epidemiology, pathophysiology, manifestations, and management. Dent Clin North Am. 2013;57(4):631-655). It is therefore divided into two main categories: (1) constitutional and (2) organ signs / symptoms. The remainder of this section refers to Fortuna and Brennan (ibid.).

[0076]

[0085] The constitutional category includes fatigue (80-100% of all patients), which seems to correlate with depression, stress, anemia, smoking habits, sedentary lifestyle, sleep, and comorbid fibromyalgia. In addition, fever is present in about 50% of patients with systemic lupus erythematosus, which may be the result of the disease, drug reactions, or systemic lupus erythematosus-inducing infections. Finally, weight loss is often observed before the diagnosis of systemic lupus erythematosus. Weight gain observed after diagnosis seems to be related to the side effects of corticosteroid treatment.

[0077]

[0086] There are more organ signs / symptoms. These include:

[0087] Musculoskeletal system: Arthralgia (often migratory), arthritis (often migratory), osteonecrosis, vascular necrosis of bone and myopathy.

[0078]

[0088] Renal: From direct damage to the kidneys by systemic lupus erythematosus. These include lupus nephritis, which causes significant morbidity and mortality. Forms of lupus nephritis include glomerulonephritis, and other lesions include renal amyloidosis, focal segmental glomerulosclerosis, IgA and IgM nephropathy, and necrotizing glomerulitis.

[0079]

[0089] Gastrointestinal: Mesenteric vasculitis and thrombosis; protein-losing enteropathy, intestinal pseudo-obstruction, and acute pancreatitis; and rarely, celiac disease, inflammatory bowel disease, eosinophilic enteritis, and pneumatosis cystoides intestinalis.

[0080]

[0090] Pulmonary: Pleuritis is most common; occasionally, pneumonia, acute dyspnea, diffuse alveolar hemorrhage, chronic interstitial pneumonia, and shrinking (vanishing) lung syndrome are observed. More rare are acute reversible hypoxemia, pulmonary embolism, pulmonary arterial hypertension, airway disease obstructive pulmonary disease, and upper respiratory tract disease.

[0081]

[0091] Cardiovascular: Valvular heart disease associated with Libman-Sacks lesions, sterile vegetations, serositis associated with pericardial disease, and venous and arterial thrombosis associated with antiphospholipid antibodies may be observed.

[0082]

[0092] Neuropsychiatric: Stroke and cerebrovascular disease (stroke, transient ischemic attack, sinus thrombosis, etc.), psychiatric symptoms include depression and cognitive impairment. In addition, symptoms such as headache, mood disorders, acute confusional states, and anxiety may occur.

[0083]

[0093] Hematological: Cytopenia and thrombosis. Patients with systemic lupus erythematosus may also present with anemia, thrombocytopenia, neutropenia, and leukopenia.

[0084]

[0094] Eyes: Approximately one-third of patients with systemic lupus erythematosus have ocular involvement, including optic nerve, periorbital, and ocular adnexal lesions, the most common being keratoconjunctivitis sicca. Eye damage can adversely affect vision.

[0085]

[0095] Cutaneous: 85% of patients with systemic lupus erythematosus have cutaneous manifestations, which may be the only organ involved. There can be three groups of mucocutaneous manifestations: (1) chronic cutaneous lupus erythematosus (CCLE), (2) subacute cutaneous lupus erythematosus (SCLE), and (3) acute cutaneous lupus erythematosus (ACLE).

[0086]

[0096] Cutaneous manifestations include malar rash, discoid lesions (localized or generalized), photosensitivity, papular / macular lesions with slight scaling, alopecia, deep nodular induration or subcutaneous nodules, white atrophy, and livedo reticularis.

[0087]

[0097] Oropharyngeal: In addition to lesions, oral candidiasis, dysphagia, and (possibly) xerostomia.

[0088]

[0098] Immunologic: Antinuclear antibody (ANA) titers are abnormal, either above the laboratory reference range or as determined by immunofluorescence or equivalent assays. Antibodies that recognize native (ds) DNA assays will give results above the laboratory reference range (for ELISA, twice the laboratory reference range is usually used). Presence of antibodies against SM nuclear antigen (anti-SM antibodies). Antiphospholipid antibodies (which may be determined by lupus anticoagulation test), false positive test for syphilis, anticardiolipin antibodies (at least twice normal or mid-high titer); anti-b2 glycoprotein 1. Low levels of complement C3, C4, or CH50 may also be present. And, in the absence of hemolytic anemia, a direct Coombs test will be positive.

[0089]

[0099] "Reducing at least one symptom of systemic lupus erythematosus" refers to partially reducing any of the symptoms listed above, whether constitutional or organ signs / symptoms.

[0090] B. Therapeutic Methods for Administration of Anti-CD20 / Anti-CD3 Bispecific Antibodies (e.g., Mosunetuzumab)

[0100] The present invention provides methods for treating a patient or population of patients with systemic lupus erythematosus comprising administering to the patient an anti-CD20 / anti-CD3 bispecific antibody (e.g., mosunetuzumab). Such treatment with an anti-CD20 / anti-CD3 bispecific antibody, such as mosunetuzumab, may be administered following administration of a corticosteroid (such as an oral corticosteroid), an antimalarial agent, or an immunosuppressant to the patient.

[0091]

[0101] Examples of corticosteroids include, for example, hydrocortisone, cortisone acetate, prednisolone, dexamethasone, betamethasone, triamcinolone, beclomethasone, methylprednisolone, or prednisone.

[0092]

[0102] Examples of anti-malarials include, for example, hydroxychloroquine.

[0093]

[0103] Examples of common immunosuppressants include azathiprine, mycophenolate, mofetil, methotrexate, cyclophosphamide, cyclosporine, tacrolimus, and sirolimus (rapamycin).

[0094]

[0104] The disclosed methods can also include cases where the patient does not have a lupus-related neuropsychiatric disorder.

[0095]

[0105] The disclosed methods can also include where the patient does not have an active overlap syndrome with mixed connective tissue disease or systemic sclerosis within one year of being administered an effective amount of mosunetuzumab.

[0096]

[0106] The disclosed methods can also include where the patient does not have fulminant or severe antiphospholipid syndrome within one year of being administered an effective amount of mosunetuzumab, except where severe antiphospholipid syndrome has been adequately controlled by administering anticoagulant therapy to a patient who has been administered an effective amount of mosunetuzumab for at least three months.

[0097]

[0107] The disclosed methods can also include where the patient has not been administered a biologic therapy for at least 12 months during which the patient is administered an effective amount of mosunetuzumab anti-CD19 antibody therapy or anti-CD20 monoclonal antibody therapy.

[0098]

[0108] The disclosed methods may also include administering an effective amount of mosunetuzumab to: (a) a patient who has not been administered an anti-CD19 antibody therapy or an anti-CD20 monoclonal antibody therapy at least 12 months prior to being administered an effective amount of mosunetuzumab; or (b) a patient who has not been administered (i) a kinase inhibitor of Janus kinase (JAK) kinase, Bruton's tyrosine kinase, or tyrosine kinase 2, or (ii) tacrolimus, cyclosporine, or voclosporin at least 30 days prior to being administered an effective amount of mosunetuzumab; or (c) a patient who has not been administered (i) cyclophosphamide, or (ii) a biologic therapy at least 2 months prior to being administered an effective amount of mosunetuzumab.

[0099]

[0109] The disclosed methods can also include cases where the patient does not have significant lupus-related kidney disease or significant kidney impairment.

[0100]

[0110] The disclosed methods may also include when the patient does not have one laboratory parameter selected from the group consisting of: (a) total bilirubin >1.5 x ULN; (b) ANC <1.5 x 109 / L (<1500 / mm3); (c) platelet count <100 x 109 / L (100,000 / mm3); (d) hemoglobin <100 g / L; (e) estimated glomerular filtration rate (eGFR) <30 ml / min / 1.73 m2 calculated according to the Chronic Kidney Disease Epidemiology Collaboration formula; and (f) positive serum human chorionic gonadotropin.

[0101]

[0111] The disclosed methods can also include where at least one symptom of SLE is reduced.

[0102]

[0112] The disclosed methods relate to methods in which administering an effective amount of mosunetuzumab comprises administering mosunetuzumab according to a dosing regimen comprising at least a first dosing cycle, wherein the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, wherein C1D1 is less than C1D2, C1D1 is between about 1.6 mg and about 5 mg, and C1D2 is between about 15 mg and about 60 mg.

[0103]

[0113] The method can also include where mosunetuzumab is administered subcutaneously.

[0104]

[0114] In one embodiment, a method of treating a patient is provided, the method comprising administering an effective amount of mosunetuzumab to the patient, where (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is between about 1.6 mg and about 5 mg on day 1 of the cycle and C1D2 is between about 15 mg and about 60 mg on day 8 of the cycle.

[0105]

[0115] In another embodiment, a method of treating a patient is provided, the method comprising administering an effective amount of mosunetuzumab to the patient, where (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is about 1.6 mg on day 1 of the cycle and C1D2 is between about 15 mg and about 60 mg on day 8 of the cycle.

[0106]

[0116] In another embodiment, a method of treating a patient is provided, the method comprising administering an effective amount of mosunetuzumab to the patient, where (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is about 1.6 mg on day 1 of the cycle and C1D2 is about 15 mg on day 8 of the cycle.

[0107]

[0117] In another embodiment, a method of treating a patient is provided, the method comprising administering an effective amount of mosunetuzumab to the patient, where (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is about 1.6 mg on day 1 of the cycle and C1D2 is about 45 mg on day 8 of the cycle.

[0108]

[0118] In another embodiment, a method of treating a patient is provided, the method comprising administering an effective amount of mosunetuzumab to the patient, where (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is about 1.6 mg on day 1 of the cycle and C1D2 is about 60 mg on day 8 of the cycle.

[0109]

[0119] In another embodiment, a method of treating a patient is provided, the method comprising administering an effective amount of mosunetuzumab to the patient, where (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is about 5 mg on day 1 of the cycle and C1D2 is between about 15 mg and about 60 mg on day 8 of the cycle.

[0110]

[0120] In another embodiment, a method of treating a patient is provided, the method comprising administering an effective amount of mosunetuzumab to the patient, where (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is about 5 mg on day 1 of the cycle and C1D2 is about 15 mg on day 8 of the cycle.

[0111]

[0121] In another embodiment, a method of treating a patient is provided, the method comprising administering an effective amount of mosunetuzumab to the patient, where (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is about 5 mg on day 1 of the cycle and C1D2 is about 45 mg on day 8 of the cycle.

[0112]

[0122] In another embodiment, a method of treating a patient is provided, the method comprising administering an effective amount of mosunetuzumab to the patient, where (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is about 5 mg on day 1 of the cycle and C1D2 is about 60 mg on day 8 of the cycle.

[0113]

[0123] In all embodiments, mosunetuzumab may be administered subcutaneously. In some implementations, mosunetuzumab may be administered intravenously.

[0114]

[0124] In all embodiments, at least one symptom of systemic lupus erythematosus is reduced, and the reduction in symptoms can be measured, for example, using Patient Global Impression of Severity (PGI-S), Physician Global Assessment (PGA), reduction in antinuclear antibody (ANA) titer, reduction in anti-double-stranded DNA (dsDNA) antibody (IgG) titer, increase in complement C3 level, or increase in complement C4 level. In some examples, the reduction in symptoms of systemic lupus erythematosus is measured using PGI-S, and the change is from "very severe" to "severe," "severe" to "moderate," "moderate" to "mild," or "mild" to "none," or even a larger change (e.g., "very severe" to "none" being extreme examples). In other embodiments, the change is measured using PGA performed by a medical provider or other appropriately trained person, and the change is a reduction from a previous assessment using PGA.

[0115]

[0125] In some embodiments, if the patient experiences cytokine release syndrome (CRS), the patient is further administered tocilizumab. In yet other embodiments, the disclosed method further comprises administering to the patient a corticosteroid, cyclophosphamide, B cell depletion therapy, or a calcineurin inhibitor. Exemplary corticosteroid examples include hydrocortisone, cortisone acetate, prednisolone, dexamethasone, betamethasone, triamcinolone, beclomethasone, methylprednisolone, or prednisone. Exemplary cell depletion therapy includes administration of rituximab, ocrelizumab, ofatumumab, or obinutuzumab. Exemplary calcineurin inhibitors include cyclosporine, tacrolimus, or bocolosporine.

[0116]

[0126] The method may also include where the patient has been receiving a stable dose of at least 40 mg / day of prednisone (or equivalent) for at least 7 days prior to receiving the effective amount of mosunetuzumab.

[0117]

[0127] The method may also include where the patient has been receiving a stable dose of an antimalarial agent for at least four weeks prior to receiving the effective amount of mosunetuzumab.

[0118]

[0128] The method may also include where the patient has been receiving a stable dose of an immunosuppressant for at least four weeks prior to receiving the effective amount of mosunetuzumab, and the immunosuppressant may be azathioprine, mycophenolate mofetil, mycophenolic acid, or methotrexate.

[0119]

[0129] The methods can also include cases where the patient does not have lupus-associated neuropsychiatric disorders such as meningitis, retinitis, cerebral vasculitis, myelopathy, demyelinating syndrome, acute confusional state, psychosis, acute stroke or stroke syndrome, cranial neuropathy, status epilepticus or seizures, cerebellar ataxia, and mononeuritis multiplex.

[0120]

[0130] The methods may also include cases where the patient has been naive to an anti-CD19 therapy, such as blinatumomab, or has been naive to an anti-CD20 therapy, such as obinutuzumab, rituximab, ocrelizumab, or ofatumumab, or has been naive to a kinase inhibitor, such as baricitinib, tofacitinib, upadacitinib, filgotinib, ibrutinib, or fenebrutinib, or has been naive to a biologic therapy, such as belimumab, ustekinumab, anifrolumab, secukinumab, or atacicept.

[0121]

[0131] The methods may also include where a reduction in at least one symptom of SLE is measured using Patient Global Impression of Severity (PGI-S), Physician Global Assessment (PGA), reduced antinuclear antibody (ANA) titer, reduced anti-double stranded DNA (dsDNA) antibody (IgG) titer, increased complement C3 levels, or increased complement C4 levels.

[0122]

[0132] The method may also include where the reduction in at least one symptom is a change in at least one step response on the PGI-S from a previous response, the change being one of "very severe" to "severe," "severe" to "moderate," "moderate" to "mild," or "mild" to "none."

[0123]

[0133] The method may also include where the reduction in at least one symptom is a change in an assessment by a health care provider or other appropriately trained professional using a PGA, where the change is a reduction from a previous assessment using the PGA.

[0124]

[0134] The method can include where the first administration cycle is for about 8 days.

[0125]

[0135] The method can include where a C1D2 dose of mosunetuzumab is administered on about day 8 of the cycle.

[0126]

[0136] In some examples, a method of treating a patient population with systemic lupus erythematosus is provided that includes administering an effective amount of mosunetuzumab.

[0127]

[0137] The disclosed methods can also include cases where the patient population does not have a lupus-related neuropsychiatric disorder.

[0128]

[0138] The disclosed methods can also include where the patient population does not have an active overlap syndrome with mixed connective tissue disease or systemic sclerosis within one year of receiving an effective amount of mosunetuzumab.

[0129]

[0139] The disclosed methods can also include where the patient population does not have fulminant or severe antiphospholipid syndrome within one year of receiving an effective amount of mosunetuzumab, except where severe antiphospholipid syndrome has been adequately controlled by administering anticoagulant therapy to patients who have been receiving an effective amount of mosunetuzumab for at least three months.

[0130]

[0140] The disclosed methods can also include where the patient has not received a biologic therapy for at least 12 months prior to receiving an effective amount of mosunetuzumab anti-CD19 antibody therapy or anti-CD20 monoclonal antibody therapy.

[0131]

[0141] The disclosed methods may also include administering an effective amount of mosunetuzumab to: (a) a patient who has not been administered an anti-CD19 antibody therapy or an anti-CD20 monoclonal antibody therapy at least 12 months prior to being administered an effective amount of mosunetuzumab; or (b) a patient who has not been administered (i) a kinase inhibitor of Janus kinase (JAK) kinase, Bruton's tyrosine kinase, or tyrosine kinase 2, or (ii) tacrolimus, cyclosporine, or voclosporin at least 30 days prior to being administered an effective amount of mosunetuzumab; or (c) a patient who has not been administered (i) cyclophosphamide, or (ii) a biologic therapy at least 2 months prior to being administered an effective amount of mosunetuzumab.

[0132]

[0142] The disclosed methods can also include cases where the patient population does not have significant lupus-related kidney disease or significant kidney impairment.

[0133]

[0143] The disclosed methods may also include where the patient population does not have one laboratory parameter selected from the group consisting of: (a) total bilirubin >1.5 x ULN; (b) ANC <1.5 x 109 / L (<1500 / mm3); (c) platelet count <100 x 109 / L (100,000 / mm3); (d) hemoglobin <100 g / L; (e) estimated glomerular filtration rate (eGFR) <30 ml / min / 1.73 m2 calculated according to the Chronic Kidney Disease Epidemiology Collaboration formula; and (f) positive serum human chorionic gonadotropin.

[0134]

[0144] The disclosed methods can also include where at least one symptom of SLE is reduced in a patient population.

[0135]

[0145] The disclosed methods relate to methods in which administering an effective amount of mosunetuzumab comprises administering mosunetuzumab according to a dosing regimen comprising at least a first dosing cycle, wherein the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, wherein C1D1 is less than C1D2, C1D1 is between about 1.6 mg and about 5 mg, and C1D2 is between about 15 mg and about 60 mg.

[0136]

[0146] The method can also include where mosunetuzumab is administered subcutaneously.

[0137]

[0147] In one embodiment, a method of treating a patient population is provided, the method comprising administering an effective amount of mosunetuzumab to a patient, where (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is between about 1.6 mg and about 5 mg on day 1 of the cycle and C1D2 is between about 15 mg and about 60 mg on day 8 of the cycle.

[0138]

[0148] In another embodiment, a method of treating a patient population is provided, the method comprising administering an effective amount of mosunetuzumab to a patient, where (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is about 1.6 mg on day 1 of the cycle and C1D2 is between about 15 mg and about 60 mg on day 8 of the cycle.

[0139]

[0149] In another embodiment, a method of treating a patient population is provided, the method comprising administering an effective amount of mosunetuzumab to a patient, where (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is about 1.6 mg on day 1 of the cycle and C1D2 is about 15 mg on day 8 of the cycle.

[0140]

[0150] In another embodiment, a method of treating a patient population is provided, the method comprising administering an effective amount of mosunetuzumab to a patient, where (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is about 1.6 mg on day 1 of the cycle and C1D2 is about 45 mg on day 8 of the cycle.

[0141]

[0151] In another embodiment, a method of treating a patient population is provided, the method comprising administering an effective amount of mosunetuzumab to a patient, where (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is about 1.6 mg on day 1 of the cycle and C1D2 is about 60 mg on day 8 of the cycle.

[0142]

[0152] In another embodiment, a method of treating a patient population is provided, the method comprising administering an effective amount of mosunetuzumab to a patient, where (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is about 5 mg on day 1 of the cycle and C1D2 is between about 15 mg and about 60 mg on day 8 of the cycle.

[0143]

[0153] In another embodiment, a method of treating a patient population is provided, the method comprising administering an effective amount of mosunetuzumab to a patient, where (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is about 5 mg on day 1 of the cycle and C1D2 is about 15 mg on day 8 of the cycle.

[0144]

[0154] In another embodiment, a method of treating a patient population is provided, the method comprising administering an effective amount of mosunetuzumab to a patient, where (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is about 5 mg on day 1 of the cycle and C1D2 is about 45 mg on day 8 of the cycle.

[0145]

[0155] In another embodiment, a method of treating a patient population is provided, the method comprising administering an effective amount of mosunetuzumab to a patient, where (a) the patient has systemic lupus erythematosus, and (b) the mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, where the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, where C1D1 is about 5 mg on day 1 of the cycle and C1D2 is about 60 mg on day 8 of the cycle.

[0146]

[0156] In all embodiments, mosunetuzumab may be administered subcutaneously. In some implementations, mosunetuzumab may be administered intravenously.

[0147]

[0157] In all embodiments, at least one symptom of systemic lupus erythematosus is reduced, and the reduction in symptoms can be measured, for example, using Patient Global Impression of Severity (PGI-S), Physician Global Assessment (PGA), reduction in antinuclear antibody (ANA) titer, reduction in anti-double-stranded DNA (dsDNA) antibody (IgG) titer, increase in complement C3 level, or increase in complement C4 level. In some examples, the reduction in symptoms of systemic lupus erythematosus is measured using PGI-S, and the change is from "very severe" to "severe," "severe" to "moderate," "moderate" to "mild," or "mild" to "none," or even a larger change (e.g., from "very severe" to "moderate"). In other embodiments, the change is measured using PGA performed by a health care provider or other appropriately trained person, and the change is a reduction from a previous assessment using PGA.

[0148]

[0158] In some embodiments, patients in the patient population may further be administered tocilizumab if the patient experiences cytokine release syndrome (CRS). In yet other embodiments, the disclosed methods further comprise administering to the patient a corticosteroid, cyclophosphamide, B cell depletion therapy, or a calcineurin inhibitor. Exemplary corticosteroid examples include hydrocortisone, cortisone acetate, prednisolone, dexamethasone, betamethasone, triamcinolone, beclomethasone, methylprednisolone, or prednisone. Exemplary cell depletion therapy includes administration of rituximab, ocrelizumab, ofatumumab, or obinutuzumab. Exemplary calcineurin inhibitors include cyclosporine, tacrolimus, or bocolosporine.

[0149]

[0159] The methods may also include where a patient in the patient population has been receiving a stable dose of at least 40 mg / day of prednisone (or equivalent) for at least 7 days prior to receiving the effective amount of mosunetuzumab.

[0150]

[0160] The methods may also include where patients in the patient population have been receiving a stable dose of an antimalarial agent for at least four weeks prior to receiving the effective amount of mosunetuzumab.

[0151]

[0161] The methods may also include where a patient in the patient population has been receiving a stable dose of an immunosuppressant for at least four weeks prior to receiving the effective amount of mosunetuzumab, where the immunosuppressant may be azathioprine, mycophenolate mofetil, mycophenolic acid, or methotrexate.

[0152]

[0162] The methods can also include cases where the patients in the patient population do not have lupus-associated neuropsychiatric disorders, such as meningitis, retinitis, cerebral vasculitis, myelopathy, demyelinating syndrome, acute confusional state, psychosis, acute stroke or stroke syndrome, cranial neuropathy, status epilepticus or seizures, cerebellar ataxia, and mononeuritis multiplex.

[0153]

[0163] The methods may also include where patients in the patient population have been naive to an anti-CD19 therapy, such as blinatumomab, or have been naive to an anti-CD20 therapy, such as obinutuzumab, rituximab, ocrelizumab, or ofatumumab, or have been naive to a kinase inhibitor, such as baricitinib, tofacitinib, upadacitinib, filgotinib, ibrutinib, or fenebrutinib, or have been naive to a biologic therapy, such as belimumab, ustekinumab, anifrolumab, secukinumab, or atacicept.

[0154]

[0164] The method may also include a reduction in at least one symptom of SLE, measured using a Patient Global Impression of Severity (PGI-S), a Physician's Global Assessment (PGA), a reduction in antinuclear antibody (ANA) titer, a reduction in anti-double stranded DNA (dsDNA) antibody (IgG) titer, an increase in complement C3 levels, or an increase in complement C4 levels.

[0155]

[0165] The method may also include where the reduction in at least one symptom is a change in at least one step response on the PGI-S from a previous response, the change being one of "very severe" to "severe," "severe" to "moderate," "moderate" to "mild," or "mild" to "none."

[0156]

[0166] The method may also include where the reduction in at least one symptom is a change in an assessment by a health care provider or other appropriately trained professional using a PGA, where the change is a reduction from a previous assessment using the PGA.

[0157]

[0167] The method can include where the first administration cycle is for about 8 days.

[0158]

[0168] The method can include where a C1D2 dose of mosunetuzumab is administered on about day 8 of the cycle.

[0159]

[0169] Any of the methods described herein may include monitoring the patient for cytokine release syndrome (CRS) (e.g., a CRS event following initiation of any of the above methods). Current clinical responses are focused on treating the patient's signs and symptoms, providing supportive care, and attempting to attenuate the inflammatory response using high doses of corticosteroids. However, this approach is not always successful, especially in cases of late intervention. The CRS grading criteria used by the methods described herein have been published by the American Society for Transplantation and Cellular Therapy (ASTCT) to define mild, moderate, severe, or life-threatening CRS and to harmonize reporting across clinical trials to allow for rapid recognition and treatment of CRS (Lee et al. Biology of Blood and Marrow Transplantation. 25(4):625-638, 2019). The ASTCT criteria are intended to be objective, easy to apply, and to more accurately classify the severity of CRS. This CRS grading system is shown in Table 1 below. TIFF2024543509000002.tif172170

[0160]

[0170] Fever is defined as a temperature of 38°C or higher not attributable to other causes. In patients with CRS who receive antipyretic or anticytokine therapy, such as tocilizumab or steroids, fever is no longer required to grade the severity of subsequent CRS. In this case, the grading of CRS is determined by hypotension and / or hypoxia.

[0161]

[0171] The CRS grade is determined by the more severe event, hypotension or hypoxia not attributable to other causes. For example, a patient with a temperature of 39.5°C, hypotension requiring one vasopressor, and hypoxia requiring a low-flow nasal cannula is classified as having grade 3 CRS.

[0162]

[0172] Low-flow nasal cannulae are defined as oxygen delivered at ≤6 L / min. Low-flow also includes blow-by oxygen supplies sometimes used in pediatrics. High-flow nasal cannulae are defined as oxygen delivered at >6 L / min.

[0163]

[0173] CRS is associated with increases in a variety of cytokines, including marked increases in IFN-g, IL-6, and TNF-a levels. Emerging evidence specifically implicates CRS and IL-6 as a central mediator. IL-6 is a proinflammatory, multifunctional cytokine produced by a variety of cell types that has been shown to be involved in a wide variety of physiological processes, including T cell activation. Regardless of the precipitating factor, CRS is associated with high IL-6 levels (Nagorsen et al. Cytokine. 25(1):31-5, 2004; Lee et al. Blood. 124(2):188-95, 2014; Doesegger et al. Clin. Transl. Immunology. 4(7):e39, 2015), and IL-6 correlates with CRS severity, with patients who experience grade 4 or 5 CRS events having much higher IL-6 levels compared to patients who do not experience CRS or who experience milder CRS (grades 0-3) (Chen et al. J. Immunol. Methods. 434:1-8, 2016).

[0164]

[0174] Therefore, blocking the inflammatory effects of IL-6 using agents that inhibit IL-6-mediated signaling to manage CRS observed in patients during a two-phase, fractionated, dose-escalating dosing regimen is an alternative to steroid treatment that is not expected to adversely affect T cell function or reduce the efficacy or clinical benefit of anti-CD20 / anti-CD3 bispecific antibody therapy in the treatment of CD20 positive cell proliferative disorders (e.g., B cell proliferative disorders).

[0165]

[0175] Tocilizumab (ACTEMRA® / RoACTEMRA®) is a recombinant, humanized, anti-human monoclonal antibody against the soluble membrane-bound IL-6R that inhibits IL-6-mediated signaling (see, e.g., WO 1992 / 019579, which is incorporated by reference in its entirety).

[0166]

[0176] If the patient has a cytokine release syndrome (CRS) event following administration of the bispecific antibody, the method may further include administering to the patient an effective amount of an interleukin-6 receptor (IL-6R) antagonist (e.g., an anti-IL-6R antibody, e.g., tocilizumab (ACTEMRA® / RoACTEMRA®)) to manage the event. In some examples, tocilizumab is administered intravenously to the patient as a single dose of about 8 mg / kg. In some examples, each dose of tocilizumab does not exceed 800 mg / dose. Other anti-IL-6R antibodies that may be used in place of or in combination with tocilizumab include sarilumab, bovalilizumab (ALX-0061), satralizumab (SA-237), and variants thereof.

[0167]

[0177] If the patient has a CRS event that does not resolve or worsen within 24 hours of administering an IL-6R antagonist to treat the symptoms of the CRS event, the method may further include administering one or more additional doses of an IL-6R antagonist (e.g., an anti-IL-6R antibody, e.g., tocilizumab) to the patient to manage the CRS event. If the CRS event is not managed through administration of an IL-6R antagonist, the patient may be administered a corticosteroid, such as methylprednisolone or dexamethasone.

[0168]

[0178] Management of the CRS event may be adjusted based on the stage of CRS and the presence of comorbidities. For example, if after administration of the bispecific antibody, the patient has a grade 2 cytokine release syndrome (CRS) event in the absence or presence of minimal comorbidities, the method may further include treating the symptoms of the grade 2 CRS event while withholding treatment with the bispecific antibody. If the grade 2 CRS event resolves to a grade ≦1 CRS event for at least three consecutive days, the method may further include resuming treatment with the bispecific antibody at the same dose. On the other hand, if the grade 2 CRS event does not resolve or deteriorate to a grade ≧3 CRS event within 24 hours of treating the symptoms of the grade 2 CRS event, the method may further include administering to the patient an effective amount of an interleukin-6 receptor (IL-6R) antagonist (e.g., an anti-IL-6R antibody, e.g., tocilizumab (ACTEMRA® / RoACTEMRA®)) to manage the grade 2 or grade ≧3 CRS event. In some examples, tocilizumab is administered intravenously to the patient as a single dose of about 8 mg / kg. In some examples, each dose of tocilizumab does not exceed 800 mg / dose. Other anti-IL-6R antibodies that may be used instead of or in combination with tocilizumab include sarilumab, bovalilizumab (ALX-0061), satralizumab (SA-237), and variants thereof.

[0169]

[0179] If the subject has a grade 2, 3 or 4 CRS event in the presence of extensive comorbidities after administration of the bispecific antibody, the method may further include an art-recognized method for alleviating the CRS event, such as administering an initial dose of an IL-6R antagonist (e.g., an anti-IL-6R antibody, e.g., tocilizumab (ACTEMRA® / RoACTEMRA®)) to the patient to manage the CRS event while withholding treatment with the bispecific antibody. Other anti-IL-6R antibodies that may be used in place of or in combination with tocilizumab include sarilumab, bovalilizumab (ALX-0061), satralizumab (SA-237), and variants thereof. In some examples, the method further includes administering an effective amount of a corticosteroid, e.g., methylprednisolone or dexamethasone, to the patient.

[0170]

[0180] In some examples, treating a patient population with previously untreated (1L) diffuse large B-cell lymphoma using the dosing regimen provided by the methods of the present invention results in a patient population with a cytokine release syndrome of grade 3 or higher (as defined by American Society for Transplantation and Cellular Therapy, 2018; ASTCT) of less than 5% (e.g., less than 4%, less than 3%, less than 2%, or less than 1%; e.g., 4%, 3%, 2%, 1%, or 0%). In some examples, the rate of cytokine release syndrome of grade 3 or higher (as defined by ASTCT) is less than 3%. In some examples, the rate of cytokine release syndrome of grade 3 or higher (as defined by ASTCT) is less than 1%. In some examples, the rate of cytokine release syndrome of grade 3 or higher (as defined by ASTCT) is 5%. In some examples, the rate of cytokine release syndrome of grade 3 or higher (as defined by ASTCT) is 3%. In some examples, the rate of cytokine release syndrome of grade 3 or higher (as defined by ASTCT) is 1%. In some instances, the rate of cytokine release syndrome grade 3 or higher (as defined by ASTCT) is 0%.

[0171] C. Bispecific antibodies that bind to CD20 and CD3

[0181] The present invention provides bispecific antibodies that bind to CD20 and CD3 (ie, anti-CD20 / anti-CD3 antibodies) that are useful in the treatment of systemic lupus erythematosus.

[0172]

[0182] In some examples, the invention provides a bispecific antibody comprising an anti-CD20 arm having a first binding domain comprising at least one, two, three, four, five or six hypervariable regions (HVRs) selected from: (a) an HVR-H1 comprising the amino acid sequence of GYTFTSYNMH (SEQ ID NO: 1); (b) an HVR-H2 comprising the amino acid sequence of AIYPGNGDTSYNQKFKG (SEQ ID NO: 2); (c) an HVR-H3 comprising the amino acid sequence of VVYYSNSYWYFDV (SEQ ID NO: 3); (d) an HVR-L1 comprising the amino acid sequence of RASSSVSYMH (SEQ ID NO: 4); (e) an HVR-L2 comprising the amino acid sequence of APSNLAS (SEQ ID NO: 5); and (f) an HVR-L3 comprising the amino acid sequence of QQWSFNPPT (SEQ ID NO: 6). In some examples, the anti-CD20 / anti-CD3 bispecific antibody comprises at least one (e.g., one, two, three, or four) of the heavy chain framework regions FR-H1, FR-H2, FR-H3, and FR-H4 comprising the sequences of SEQ ID NOs: 17-20, respectively, and / or at least one (e.g., one, two, three, or four) of the light chain framework regions FR-L1, FR-L2, FR-L3, and FR-L4 comprising the sequences of SEQ ID NOs: 21-24, respectively. In some examples, the bispecific antibody comprises: (a) a heavy chain variable (VH) domain having at least 90% sequence identity (e.g., at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% sequence identity) to SEQ ID NO: 7, or comprising the amino acid sequence of SEQ ID NO: 7; (b) a light chain variable (VL) domain having at least 90% sequence identity (e.g., at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% sequence identity) to SEQ ID NO: 8, or comprising the amino acid sequence of SEQ ID NO: 8; or (c) an anti-CD20 arm comprising a first binding domain comprising a VH domain as in (a) and a VL domain as in (b). Thus, in some examples, the first binding domain comprises a VH domain comprising the amino acid sequence of SEQ ID NO: 7, and a VL domain comprising the amino acid sequence of SEQ ID NO: 8.

[0173]

[0183] In some examples, the invention provides a bispecific antibody comprising an anti-CD3 arm having a second binding domain comprising at least one, two, three, four, five or six HVRs selected from: (a) HVR-H1 comprising the amino acid sequence of NYYIH (SEQ ID NO: 9); (b) HVR-H2 comprising the amino acid sequence of WIYPGDGNTKYNEKFKG (SEQ ID NO: 10); (c) HVR-H3 comprising the amino acid sequence of DSYSNYYFDY (SEQ ID NO: 11); (d) HVR-L1 comprising the amino acid sequence of KSSQSLLNSRTRKNYLA (SEQ ID NO: 12); (e) HVR-L2 comprising the amino acid sequence of WASTRES (SEQ ID NO: 13); (f) HVR-L3 comprising the amino acid sequence of TQSFILRT (SEQ ID NO: 14). In some examples, the anti-CD20 / anti-CD3 bispecific antibody comprises at least one (e.g., one, two, three, or four) of the heavy chain framework regions FR-H1, FR-H2, FR-H3, and FR-H4 comprising the sequences of SEQ ID NOs:25-28, respectively, and / or at least one (e.g., one, two, three, or four) of the light chain framework regions FR-L1, FR-L2, FR-L3, and FR-L4 comprising the sequences of SEQ ID NOs:29-32, respectively. In some examples, the bispecific antibody comprises: (a) a VH domain having at least 90% sequence identity (e.g., at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% sequence identity) to SEQ ID NO: 15, or the amino acid sequence of SEQ ID NO: 15; (b) a VL domain having at least 90% sequence identity (e.g., at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% sequence identity) to SEQ ID NO: 16, or the amino acid sequence of SEQ ID NO: 16; or (c) an anti-CD3 arm comprising a second binding domain comprising a VH domain as in (a) and a VL domain as in (b). Thus, in some examples, the second binding domain comprises a VH domain comprising the amino acid sequence of SEQ ID NO: 15 and a VL domain comprising the amino acid sequence of SEQ ID NO: 16.

[0174]

[0184] In some examples, the present invention provides an HVR-H1 comprising an amino acid sequence of GYTFTSYNMH (SEQ ID NO: 1); (b) an HVR-H2 comprising an amino acid sequence of AIYPGNGDTSYNQKFKG (SEQ ID NO: 2); (c) an HVR-H3 comprising an amino acid sequence of VVYYSNSYWYFDV (SEQ ID NO: 3); (d) an HVR-L1 comprising an amino acid sequence of RASSSVSYMH (SEQ ID NO: 4); (e) an HVR-L2 comprising an amino acid sequence of APSNLAS (SEQ ID NO: 5); and (f) an HVR-L3 comprising an amino acid sequence of QQWSFNPPT (SEQ ID NO: 6). and (2) an anti-CD20 arm having a first binding domain comprising at least one, two, three, four, five or six HVRs selected from the group consisting of (a) an HVR-H1 having an amino acid sequence of NYYIH (SEQ ID NO: 9); (b) an HVR-H2 having an amino acid sequence of WIYPGDGNTKYNEKFKG (SEQ ID NO: 10); (c) an HVR-H3 having an amino acid sequence of DSYSNYYFDY (SEQ ID NO: 11); (d) an HVR-L1 having an amino acid sequence of KSSQSLLNSRTRKNYLA (SEQ ID NO: 12); (e) an HVR-L2 having an amino acid sequence of WASTRES (SEQ ID NO: 13). and (f) HVR-L3 comprising the amino acid sequence of TQSFILRT (SEQ ID NO: 14). In some examples, the anti-CD20 / anti-CD3 bispecific antibody comprises an anti-CD3 arm having a second binding domain comprising at least one, two, three, four, five or six HVRs selected from (1) at least one (e.g., 1, 2, 3, or 4) of the heavy chain framework regions FR-H1, FR-H2, FR-H3 and FR-H4 comprising the sequences of SEQ ID NOs: 17-20, respectively, and / or (c) at least one (e.g., 1, 2, 3, or 4) of the heavy chain framework regions FR-H1, FR-H2, FR-H3 and FR-H4 comprising the amino acid sequence of SEQ ID NOs: 17-20, respectively. and (2) at least one (e.g., 1, 2, 3, or 4) of the light chain framework regions FR-L1, FR-L2, FR-L3, and FR-L4 comprising the sequences of SEQ ID NOs: 21 to 24, and at least one (e.g., 1, 2, 3, or 4) of the heavy chain framework regions FR-H1, FR-H2, FR-H3, and FR-H4 comprising the sequences of SEQ ID NOs: 25 to 28, respectively, and / or at least one (e.g., 1, 2, 3, or 4) of the light chain framework regions FR-L1, FR-L2, FR-L3, and FR-L4 comprising the sequences of SEQ ID NOs: 29 to 32, respectively.In some examples, the anti-CD20 / anti-CD3 bispecific antibody comprises: (1) (a) a VH domain having at least 90% sequence identity (e.g., at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity) to SEQ ID NO:7, or the amino acid sequence of SEQ ID NO:7; (b) a VL domain having at least 90% sequence identity (e.g., at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity) to SEQ ID NO:8, or the amino acid sequence of SEQ ID NO:8; (c) a first binding domain comprising a VH as in (a) and a VL as in (b). an anti-CD20 arm and (2) (a) a VH domain having an amino acid sequence having at least 90% sequence identity (e.g., at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% sequence identity) to SEQ ID NO: 15, or the amino acid sequence of SEQ ID NO: 15; (b) a VL domain having at least 90% sequence identity (e.g., at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% sequence identity) to SEQ ID NO: 16, or the amino acid sequence of SEQ ID NO: 16; or (c) an anti-CD3 arm comprising a second binding domain comprising a VH as in (a) and a VL as in (b). In some examples, the anti-CD20 / anti-CD3 bispecific antibody comprises (1) a first binding domain comprising a VH domain comprising the amino acid sequence of SEQ ID NO:7 and a VL domain comprising the amino acid sequence of SEQ ID NO:8, and (2) a second binding domain comprising a VH domain comprising the amino acid sequence of SEQ ID NO:15 and a VL domain comprising the amino acid sequence of SEQ ID NO:16.

[0175]

[0185] In some examples, the anti-CD20 / anti-CD3 bispecific antibody is mosunetuzumab, which has International Nonproprietary Name (INN) List 117 (WHO Drug Information, Vol. 31, No. 2, 2017, p. 303) or CAS Registry Number 1905409-39-3, and has (1) an anti-CD20 arm comprising the heavy and light chain sequences of SEQ ID NOs: 33 and 34, respectively, and (2) an anti-CD3 arm comprising the heavy and light chain sequences of SEQ ID NOs: 35 and 36, respectively. In some examples, the anti-CD20 / anti-CD3 bispecific antibody comprises: (1) a heavy chain comprising: (a) an amino acid sequence having at least 90% sequence identity (e.g., at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% sequence identity) to SEQ ID NO: 33, or the amino acid sequence of SEQ ID NO: 33; (b) a light chain comprising an amino acid sequence having at least 90% sequence identity (e.g., at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% sequence identity) to SEQ ID NO: 34, or the amino acid sequence of SEQ ID NO: 34; (c) a heavy chain as in (a) and a light chain as in (b). and (2) an anti-CD20 arm comprising: (a) a heavy chain comprising an amino acid sequence having at least 90% sequence identity (e.g., at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% sequence identity) to SEQ ID NO: 35, or the amino acid sequence of SEQ ID NO: 35; (b) a light chain comprising an amino acid sequence having at least 90% sequence identity (e.g., at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% sequence identity) to SEQ ID NO: 36, or the amino acid sequence of SEQ ID NO: 36; or (c) an anti-CD3 arm comprising a second binding domain comprising a heavy chain as in (a) and a light chain as in (b). In some examples, the anti-CD20 / anti-CD3 bispecific antibody comprises (1) an anti-CD20 arm comprising a first binding domain comprising a heavy chain comprising the amino acid sequence of SEQ ID NO:33 and a light chain comprising the amino acid sequence of SEQ ID NO:34, and (2) an anti-CD3 arm comprising a second binding domain comprising a heavy chain comprising the amino acid sequence of SEQ ID NO:35 and a light chain comprising the amino acid sequence of SEQ ID NO:36.

[0176]

[0186] The amino acid sequence of mosunetuzumab is summarized in Table 2 below. TIFF2024543509000003.tif71170

[0177]

[0187] Anti-CD20 / anti-CD3 bispecific antibodies can be produced using recombinant methods and compositions, for example, as described in US Pat. No. 4,816,567.

[0178]

[0188] In some examples, an anti-CD20 / anti-CD3 bispecific antibody according to any of the above embodiments may incorporate any of the features, either alone or in combination, as described in Section C below.

[0179] D. Antibody Formats and Characteristics

[0189] The methods described herein may further include any of the antibodies described above, where the antibody comprises any of the characteristics as described below, either alone or in combination.

[0180]

[0190] 1. Antibody affinity

[0191] In certain instances, the anti-CD20 / anti-CD3 bispecific antibody has a concentration of ≦1 μM, ≦100 nM, ≦10 nM, ≦1 nM, ≦0.1 nM, ≦0.01 nM, or ≦0.001 nM (e.g., 10 -8 M or less, e.g. 10 -8 M~10 -13 M, for example 10 -9 M~10 -13 Dissociation constant (K D ).

[0181]

[0192] In one example, K D is measured by radiolabeled antigen binding assay (RIA). In one example, an RIA is performed using an antibody of interest and a Fab version of its antigen. For example, the solution binding affinity of a Fab for an antigen is determined by the minimum concentration of ( 125I) labeled antigen and then captured the bound antigen on a plate coated with anti-Fab antibody (see, e.g., Chen et al., J. Mol. Biol. 293:865-881 (1999)). To establish conditions for the assay, MICROTITER® multiwell plates (Thermo Scientific) are coated overnight with 5 μg / ml of capture anti-Fab antibody (Cappel Labs) in 50 mM sodium carbonate (pH 9.6), followed by blocking with 2% (1 / v) bovine serum albumin in PBS for 2-5 hours at room temperature (approximately 23° C.). In non-adsorbent plates (Nunc #269620), 100 pM or 26 pM [ 125 I]-antigen is mixed with serial dilutions of the Fab of interest (e.g., consistent with the evaluation of anti-VEGF antibody Fab-12 in Presta et al., Cancer Res. 57:4593-4599 (1997)). The Fab of interest is then incubated overnight, however, incubation may continue for longer periods (e.g., about 65 hours) to ensure equilibrium is reached. The mixture is then transferred to a capture plate for incubation at room temperature (e.g., 1 hour). The solution is then removed and the plate is washed 8 times with 0.1% polysorbate 20 (TWEEN-20®) in PBS. When the plate is dry, 150 μL / well of scintillant (MICROSCINT-20®; Packard) is added and the plate is counted in a TOPCOUNT® gamma counter (Packard) for 10 minutes. The concentration of Fab that results in 20% or less of maximum binding is selected for use in competitive binding assays.

[0182]

[0193] According to another example, K Dis measured using a BIACORE® surface plasmon resonance assay. For example, assays using a BIACORE®-2000 or BIACORE®-3000 (BIACORE®, Inc., Piscataway, NJ) are performed at 25° C. using an immobilized antigen CM5 chip at about 10 response units (RU). In one example, a carboxymethylated dextran biosensor chip (CM5, BIACORE®, Inc.) is activated with N-ethyl-N'-(3-dimethylaminopropyl)-carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) according to the supplier's instructions. Antigen is diluted to 5 μg / ml (about 0.2 μM) with 10 mM sodium acetate (pH 4.8) and then injected at a flow rate of 5 μl / min to reach about 10 response units (RU) of bound protein. After injection of antigen, 1 M ethanolamine is injected to block unreacted groups. For kinetic measurements, two-fold serial dilutions of Fab (0.78 nM to 500 nM) are injected in PBS containing 0.05% polysorbate 20 (TWEEN-20®) surfactant (PBST) at 25° C. with a flow rate of approximately 25 μl / min. Association rates (k on ) and dissociation rate (k off ) is calculated using a simple one-to-one Langmuir binding model (BIACORE® Evaluation Software version 3.2) by simultaneously fitting the association and dissociation sensorgrams. D ) is k off / k on The on rate is calculated as a ratio of 10 to 10. See, for example, Chen et al., J. Mol. Biol. 293:865-881 (1999). 6 M- 1 s- 1If the on rate exceeds 100%, the on rate can be determined using a fluorescence quenching technique that measures the increase or decrease in fluorescence emission intensity (excitation = 295 nm, emission = 340 nm, 16 nm band pass) of 20 nM anti-antigen antibody (Fab type) in PBS (pH 7.2) at 25°C in the presence of increasing antigen concentrations as measured in a spectrometer such as a spectrophotometer equipped with stopped flow (Aviv Instruments) or an 8000 series SLM-AMINCO™ spectrophotometer (ThermoSpectronic) equipped with a stirred cuvette.

[0183]

[0194] 2. Antibody fragment

[0195] In certain examples, the anti-CD20 / anti-CD3 bispecific antibodies provided herein are antibody fragments. Antibody fragments include, but are not limited to, Fab, Fab', Fab'-SH, F(ab')2, Fv, and scFv fragments, as well as other fragments described below. For a review of certain antibody fragments, see Hudson et al. Nat. Med. 9:129-134 (2003). For a review of scFv fragments, see, e.g., Pluckthun, The Pharmacology of Monoclonal Antibodies, vol. 113, Rosenburg and Moore eds., (Springer-Verlag, New York), pp. 269-315 (1994). See also WO 93 / 16185, and U.S. Pat. Nos. 5,571,894 and 5,587,458. See US Pat. No. 5,869,046 for a discussion of Fab and F(ab')2 fragments that comprise salvage receptor binding epitope residues and have increased in vivo half-lives.

[0184]

[0196] Diabodies are antibody fragments with two antigen-binding sites that can be bivalent or bispecific. See, e.g., EP 404,097, WO 1993 / 01161, Hudson et al. Nat. Med. 9:129-134 (2003); and Hollinger et al. Proc. Natl. Acad. Sci. USA 90:6444-6448 (1993). Triabodies and tetrabodies are also described in Hudson et al., Nat. Med. 9:129-134 (2003).

[0185]

[0197] A single domain antibody is an antibody fragment that contains all or a portion of the heavy chain variable domain or all or a portion of the light chain variable domain of an antibody. In certain instances, a single domain antibody is a human single domain antibody (Domantis, Inc., Waltham, MA; see, e.g., U.S. Patent No. 6,248,516 B1).

[0186]

[0198] Antibody fragments may be produced by a variety of techniques, including, but not limited to, proteolytic digestion of intact antibodies and production by recombinant host cells (e.g., E. coli or phages), as described herein.

[0187]

[0199] 3. Chimeric and humanized antibodies

[0200] In certain examples, the anti-CD20 / anti-CD3 bispecific antibodies provided herein are chimeric antibodies. Certain chimeric antibodies are described, for example, in U.S. Patent No. 4,816,567; and Morrison et al. Proc. Natl. Acad. Sci. USA, 81:6851-6855 (1984). In one example, the chimeric antibody comprises a non-human variable region (e.g., a variable region derived from a non-human primate, such as a mouse, rat, hamster, rabbit, or monkey) and a human constant region. In a further example, the chimeric antibody is a "class-switched" antibody whose class or subclass has been changed from that of the parent antibody. The chimeric antibody includes an antigen-binding fragment thereof.

[0188]

[0201] In certain instances, a chimeric antibody is a humanized antibody. Typically, a non-human antibody is humanized to reduce immunogenicity to humans while retaining the specificity and affinity of the parent non-human antibody. In general, a humanized antibody comprises one or more variable domains in which the HVRs, e.g., CDRs (or portions thereof) are derived from a non-human antibody and the FRs (or portions thereof) are derived from a human antibody sequence. The humanized antibody also optionally comprises at least a portion of a human constant region. In some instances, some FR residues of the humanized antibody are replaced with the corresponding residues from the non-human antibody (e.g., the antibody from which the HVR residues are derived), e.g., to restore or improve antibody specificity or affinity.

[0189]

[0202] Humanized antibodies and methods for making them are reviewed in Almagro and Fransson, Front. Biosci. 13:1619-1633 (2008) and further described, for example, in Riechmann et al., Nature 332:323-329 (1988); Queen et al., Proc. Natl Acad. Sci. USA 86:10029-10033 (1989); U.S. Patent Nos. 5,821,337, 7,527,791, 6,982,321, and 7,087,409; Kashmiri et al., Methods 36:25-34(2005)) (describing specificity determining region (SDR) grafting); Padlan, Mol. Immunol. 28:489-498(1991) (describing "resurfacing"); Dall'Acqua et al., Methods 36:43-60(2005) (describing "FR shuffling"; and Osbourn et al., Methods 36:61-68(2005) and Klimka et al., Br. J. Cancer, 83:252-260(2000) (describing a "guided selection" approach to FR shuffling).

[0190]

[0203] Human framework regions that can be used for humanization include, but are not limited to, framework regions selected using the "best-fit" method (see, e.g., Sims et al., J. Immunol. 151:2296 (1993)); framework regions derived from consensus sequences of human antibodies of a particular subgroup of light or heavy chain variable regions (see, e.g., Carter et al., Proc. Natl. Acad. Sci. USA, 89:4285 (1992); and Presta et al., J. Immunol., 151:2623 (1993)); human mature (somatically mutated) framework regions or human germline framework regions (see, e.g., Almagro and Fransson, Front. Biosci. 13:1619-1633 (2008)); and framework regions derived from screening of FR libraries (see, e.g., Baca et al., J. Immunol. 13:1619-1633 (2008)). al., J. Biol. Chem. 272:10678-10684 (1997) and Rosok et al., J. Biol. Chem. 271:22611-22618 (1996).

[0191]

[0204] 4. Human antibodies

[0205] In certain examples, the anti-CD20 / anti-CD3 bispecific antibody is a human antibody. Human antibodies can be produced using a variety of techniques known in the art. Human antibodies are generally described in van Dijk and van de Winkel, Curr. Opin. Pharmacol. 5:368-74 (2001) and Lonberg, Curr. Opin. Immunol. 20:450-459 (2008).

[0192]

[0206] Human antibodies may be prepared by administering immunogens to transgenic animals that have been modified to produce intact human antibodies or intact antibodies with human variable regions in response to antigenic challenge. Such animals typically contain all or part of the human immunoglobulin loci, which either replace endogenous immunoglobulin loci or are present extrachromosomally or randomly integrated into the animal's chromosomes. In such transgenic mice, the endogenous immunoglobulin loci are generally inactivated. For a review of methods for obtaining human antibodies from transgenic animals, see Lonberg, Nat. Biotech. 23:1117-1125 (2005). See also, e.g., XENOMOUSE. TM (See also U.S. Patent Nos. 6,075,181 and 6,150,584, which describe HuMab® technology; U.S. Patent No. 5,770,429, which describes HuMab® technology; U.S. Patent No. 7,041,870, which describes KM MOUSE® technology, and U.S. Patent Application Publication No. 2007 / 0061900, which describes VelociMouse® technology.) The human variable regions from intact antibodies produced by such animals may be further modified by combining with different human constant regions.

[0193]

[0207] Human antibodies can also be produced by hybridoma-based methods. Human myeloma cell lines and mouse-human heteromyeloma cell lines for the production of human monoclonal antibodies have been described (see, for example, Kozbor J.Immunol., 133:3001 (1984); Brodeur et al., Monoclonal Antibody Production Techniques and Applications, pp.51-63 (Marcel Dekker, Inc., New York, 1987); and Boerner et al., J.Immunol., 147:86 (1991)). Human antibodies generated via human B-cell hybridoma technology are also described in Li et al., Proc.Natl.Acad.Sci.USA, 103:3557-3562 (2006). Additional methods include, for example, U.S. Patent No. 7,189,826 (describing the production of monoclonal human IgM antibodies from hybridoma cell lines) and Ni, Xiandai Mianyixue, 26(4):265-268 (2006) (describing human-human hybridomas). Human hybridoma technology (trioma technology) is also described in Vollmers and Brandlein, Histology and Histopathology, 20(3):927-937 (2005) and Vollmers and Brandlein, Methods and Findings in Experimental and Clinical Pharmacology, 27(3):185-91 (2005).

[0194]

[0208] Human antibodies may also be generated by isolating Fv clone variable domain sequences selected from a human-derived phage display library. Such variable domain sequences may then be combined with the desired human constant domains. Techniques for selecting human antibodies from antibody libraries are described below.

[0195]

[0209] 5. Library-derived antibodies

[0210] Anti-CD20 / anti-CD3 bispecific antibodies of the invention can be isolated by screening combinatorial libraries of antibodies having the desired activity or activities. For example, various methods are known in the art for generating phage display libraries and screening such libraries for antibodies possessing the desired binding properties. Reviews of such methods can be found in, e.g., Hoogenboom et al., Methods in Molecular Biology 178:1-37 (O'Brien et al., ed., Human Press, Totowa, NJ, 2001), as well as in, e.g., McCafferty et al., Nature 348:552-554; Clackson et al., Nature 352:624-628 (1991); Marks et al., J. Mol. Biol. 222:581-597 (1992); Marks and Bradbury, Methods in Molecular Biology 248:161-175 (Lo, ed., Human Press, Totowa, NJ, 2003); Sidhu et al., J. Mol. Biol. 338(2):299-310 (2004); Lee et al. al., J. Mol. Biol. 340(5):1073-1093 (2004); Fellouse, Proc. Natl. Acad. Sci. USA 101(34):12467-12472 (2004); and Lee et al., J. Immunol. Methods 284(1-2):119-132 (2004).

[0196]

[0211] In a particular phage display method, repertoires of VH and VL genes can be cloned separately by polymerase chain reaction (PCR), randomly recombined in a phage library, and then screened for antigen-binding phage as described in Winter et al., Ann. Rev. Immunol Immunol. 12:433-455 (1994). Phages typically display antibody fragments, either as single-chain Fv (scFv) fragments or as Fab fragments. Libraries from immunized sources provide high affinity antibodies to the immunogen without the need to construct hybridomas. Alternatively, naive repertoires can be cloned (e.g., from humans) to provide a single source of antibodies against a wide range of non-self and self antigens without immunization, as described in Griffiths et al., EMBO J, 12:725-734 (1993). Finally, naive libraries can also be synthetically generated by cloning unrearranged V gene segments from stem cells and using PCR primers containing random sequences to encode the highly variable CDR3 regions and achieve rearrangement in vitro, as described in Hoogenboom and Winter, J. Mol. Biol., 227:381-388 (1992). Patent publications describing human antibody phage display include, for example, U.S. Patent No. 5,750,373, and U.S. Patent Publication Nos. 2005 / 0079574, 2005 / 0119455, 2005 / 0266000, 2007 / 0117126, 2007 / 0160598, 2007 / 0237764, 2007 / 0292936, and 2009 / 0002360.

[0197]

[0212] Anti-CD20 / anti-CD3 bispecific antibodies or antibody fragments isolated from a human antibody library are considered herein to be human antibodies or human antibody fragments.

[0198]

[0213] 6. Antibody variants

[0214] In certain instances, amino acid sequence variants of the anti-CD20 / anti-CD3 bispecific antibodies of the invention are contemplated. For example, it may be desirable to improve the binding affinity and / or other biological properties of the antibody. Amino acid sequence variants of the antibody may be prepared by introducing appropriate modifications into the nucleotide sequence encoding the antibody or by peptide synthesis. Such modifications include, for example, but are not limited to, deletions of, and / or insertions into, and / or substitutions of, residues within the amino acid sequences of the antibody. Any combination of deletions, insertions, and substitutions can be made to arrive at the final construct, provided that the final construct exhibits the desired properties, e.g., antigen binding.

[0199]

[0215] Substitution, insertion, and deletion variants

[0216] In certain examples, anti-CD20 / anti-CD3 bispecific antibody variants are provided that have one or more amino acid substitutions. Target sites for substitution mutagenesis include HVRs and FRs. Conservative substitutions are provided in Table 3 under the heading of "preferred substitutions." More substantial changes are provided in Table 3 under the heading of "exemplary substitutions," and as further described below with respect to amino acid side chain classes. Amino acid substitutions can be introduced into the antibody of interest, and the products can be screened for the desired activity, e.g., retained / improved antigen binding, reduced immunogenicity, or improved ADCC or CDC. TIFF2024543509000004.tif115170

[0200]

[0217] Amino acids can be grouped according to common side chain properties: (1) Hydrophobic: Norleucine, Met, Ala, Val, Leu, Ile; (2) Neutral and hydrophilic: Cys, Ser, Thr, Asn, Gln; (3) Acidic: Asp, Glu; (4) Basic: His, Lys, Arg; (5) Residues that affect chain orientation: Gly, Pro; (6) Aromatic: Trp, Tyr, Phe.

[0201]

[0218] Non-conservative substitutions involve exchanging a member of one of these classes for another class.

[0202]

[0219] Certain substitutional variants involve substituting one or more hypervariable region residues of a parent antibody (e.g., a humanized or human antibody). Generally, the resulting variants selected for further testing have a modified (e.g., improved) certain biological property (e.g., increased affinity, decreased immunogenicity) compared to the parent antibody and / or substantially retain certain biological property of the parent antibody. An exemplary substitutional variant is an affinity matured antibody, which may be conveniently generated, for example, using phage display-based affinity maturation techniques as described herein. Briefly, one or more HVR residues are mutated and variant antibodies displayed on phage are screened for a particular biological activity (e.g., binding affinity).

[0203]

[0220] Alterations (e.g., substitutions) can be made in the HVRs, for example, to improve antibody affinity. Such alterations may be made in "hot spots" of the HVRs, i.e., residues encoded by codons that undergo frequent mutation during somatic maturation (see, e.g., Chowdhury, Methods Mol. Biol. 207:179-196 (2008)), and / or in antigen-facing residues, and the resulting variants VH or VL are tested for binding affinity. Affinity maturation by construction of and reselection from secondary libraries is described, for example, in Hoogenboom et al. in Methods in Molecular Biology 178:1-37 (O'Brien et al., ed., Human Press, Totowa, NJ, (2001)). In some examples of affinity maturation, diversity is introduced into the variable genes selected for maturation by any of a variety of methods (e.g., error-prone PCR, chain shuffling, or oligonucleotide-directed mutagenesis). A secondary library is then generated. The library is then screened to identify variants with the desired affinity. Another method for introducing diversity involves an HVR-directed approach, in which several HVR residues (e.g., 4-6 residues at a time) are randomized. HVR residues involved in antigen binding may be specifically identified, for example, using alanine scanning mutagenesis or modeling. In particular, CDR-H3 and CDR-L3 are often targeted.

[0204]

[0221] In certain instances, substitutions, insertions, or deletions may occur within one or more HVRs, so long as such changes do not substantially reduce the ability of the antibody to bind to the antigen. For example, conservative changes (e.g., conservative substitutions) that do not substantially reduce binding affinity may be made in the HVRs. Such changes may, for example, be outside of the antigen contact residues in the HVRs. In certain instances of the variant VH and VL sequences described above, each HVR is either unaltered or contains no more than one, two, or three amino acid substitutions.

[0205]

[0222] A useful method for identifying antibody residues or regions that can be targeted for mutagenesis is called "alanine scanning mutagenesis" as described in Cunningham and Wells (1989) Science, 244:1081-1085. In this method, a residue or group of target residues (e.g., charged residues, e.g., Arg, Asp, His, Lys, and Glu) is identified and replaced by neutral or negatively charged amino acids (e.g., alanine or polyalanine) to determine whether the antibody-antigen interaction is affected. Further substitutions may be introduced at amino acid positions that show functional sensitivity to the initial substitution. Alternatively, or additionally, contact points between the antibody and the antigen are identified from a crystal structure of the antigen-antibody complex. Such contact and adjacent residues may be targeted or eliminated as candidates for substitution. The variants may be screened to determine whether they are mobile and contain the desired properties.

[0206]

[0223] Amino acid sequence insertions include amino- and / or carboxy-terminal fusions ranging in length from one residue to polypeptides containing 100 or more residues, as well as intrasequence insertions of single or multiple amino acid residues. An example of a terminal insertion includes an antibody with an N-terminal methionyl residue. Other insertional variants of the antibody molecule include the fusion to the N- or C-terminus of the antibody to an enzyme (e.g., for ADEPT) or a polypeptide which increases the serum half-life of the antibody.

[0207]

[0224] B. Glycosylation variants

[0225] In certain instances, the anti-CD20 / anti-CD3 bispecific antibodies of the invention can be altered to increase or decrease the extent to which the antibody is glycosylated. Addition or deletion of glycosylation sites to an anti-CD20 / anti-CD3 bispecific antibody of the invention can be conveniently accomplished by altering the amino acid sequence to create or remove one or more glycosylation sites.

[0208]

[0226] If the antibody comprises an Fc region, the carbohydrate attached thereto may be altered. Typically, natural antibodies produced by mammalian cells contain a branched, biantennary oligosaccharide that is usually attached by an N-linkage to Asn297 in the CH2 domain of the Fc region. See, for example, Wright et al. TIBTECH 15:26-32 (1997). The oligosaccharide may contain a variety of carbohydrates, such as mannose, N-acetylglucosamine (GlcNAc), galactose and sialic acid, as well as fucose attached to the GlcNAc in the "stem" of the biantennary oligosaccharide structure. In some instances, modifications of the oligosaccharides in the antibodies of the invention are made to generate antibody variants with improved specific properties.

[0209]

[0227] In one example, anti-CD20 / anti-CD3 bispecific antibody variants are provided that have carbohydrate structures attached (directly or indirectly) to the Fc region that lack fucose. For example, the amount of fucose in such antibodies may be 1%-80%, 1%-65%, 5%-65% or 20%-40%. The amount of fucose is determined by calculating the average amount of fucose in the glycan at Asn297 relative to the sum of all glycan structures attached to Asn297 (e.g., complex structures, hybrid structures, and high mannose structures) measured by MALDI-TOF mass spectrometry, e.g., as described in WO 2008 / 077546. Asn297 refers to an asparagine residue located at about position 297 (Fc region residues in EU numbering) in the Fc region, although Asn297 may also be located ±3 amino acids upstream or downstream from position 297, i.e., between positions 294 and 300, due to minor sequence variance in antibodies. Such fucosylation variants may have improved ADCC function. See, e.g., U.S. Patent Application Publication Nos. 2003 / 0157108 (Presta, L.); 2004 / 0093621 (Kyowa Hakko Co., Ltd.). Examples of publications relating to "defucosylated" or "fucose-deficient" antibody variants include U.S. Patent Application Publication Nos. 2003 / 0157108; WO 2000 / 61739; WO 2001 / 29246; U.S. Patent Application Publication Nos. 2003 / 0115614; 2002 / 0164328; 2004 / 0093621; and 2004 / 0093622. 132140; WO 2004 / 0110704; WO 2004 / 0110282; WO 2004 / 0109865; WO 2003 / 085119; WO 2003 / 084570; WO 2005 / 035586; WO 2005 / 035778; WO 2005 / 053742; WO 2002 / 031140; Okazaki et al. J. Mol. Biol. 336:1239-1249 (2004); Yamane-Ohnuki et al. Biotech. Bioeng. 87:614 (2004).Examples of cell lines capable of producing defucosylated antibodies include Lec13 CHO cells, which are deficient in protein fucosylation (Ripka et al. Arch. Biochem. Biophys. 249:533-545 (1986); US Patent Application Publication No. 2003 / 0157108 A1, Presta, L; and WO 2004 / 056312 A1, Adams et al., especially Example 11), and knockout cell lines, such as α-1,6-fucosyltransferase gene, FUT8, knockout CHO cells (see, for example, Yamane-Ohnuki et al. Biotech. Bioeng. 87:614 (2004); Kanda, Y. et al., Biotechnol. Bioeng., 94(4):680-688 (2006); and WO 2003 / 085107).

[0210]

[0228] In view of the above, in some examples, the method of the invention comprises administering to a patient a variant of an anti-CD20 / anti-CD3 bispecific antibody comprising an aglycosylation site mutation in the context of a split-dose escalation regimen. In some examples, the aglycosylation site mutation reduces an effector function of the antibody. In some examples, the aglycosylation site mutation is a substitution mutation. In some examples, the antibody comprises a substitution mutation in the Fc region that reduces an effector function. In some examples, the substitution mutation is at amino acid residues N297, L234, L235, and / or D265 (EU numbering). In some examples, the substitution mutation is selected from the group consisting of N297G, N297A, L234A, L235A, D265A, and P329G (EU numbering). In some examples, the substitution mutation is at amino acid residue N297 (EU numbering). In a preferred example, the substitution mutation is N297A (EU numbering). In some embodiments, the anti-CD20 arm of the anti-CD20 / anti-CD3 bispecific antibody further comprises the following substitution mutations (EU numbering): T366W and N297G. In some embodiments, the anti-CD3 arm of the anti-CD20 / anti-CD3 bispecific antibody further comprises the following substitution mutations (EU numbering): T366S, L368A, Y407V and N297G. In some embodiments, (a) the anti-CD20 arm further comprises the following substitution mutations (EU numbering): T366W and N297G, and (b) the anti-CD3 arm further comprises the following substitution mutations (EU numbering): T366S, L368A, Y407V and N297G.

[0211]

[0229] Further provided are anti-CD20 / anti-CD3 bispecific antibody variants with bisected oligosaccharides, e.g., biantennary oligosaccharides attached to the Fc region of the antibody are bisected by GlcNAc. Such antibody variants may have reduced fucosylation and / or improved ADCC function. Examples of such antibody variants are described, for example, in WO 2003 / 011878 (Jean-Mairet et al.); U.S. Pat. No. 6,602,684 (Umana et al.); and U.S. Pat. App. Pub. No. 2005 / 0123546 (Umana et al.). Also provided are antibody variants with at least one galactose residue in the oligosaccharide attached to the Fc region. Such antibody variants may have improved CDC function. Such antibody variants are described, for example, in WO 1997 / 30087 (Patel et al.); WO 1998 / 58964 (Raju, S.); and WO 1999 / 22764 (Raju, S.).

[0212]

[0230] c. Fc region variants

[0231] In certain examples, one or more amino acid modifications are introduced into the Fc region of an anti-CD20 / anti-CD3 bispecific antibody of the invention, thereby generating an Fc region variant (see, e.g., U.S. Patent Application Publication No. 2012 / 0251531). The Fc region variant may comprise a human Fc region sequence (e.g., a human IgG1, IgG2, IgG3, or IgG4 Fc region) that comprises an amino acid modification (e.g., a substitution) at one or more amino acid positions.

[0213]

[0232] In certain instances, the present invention contemplates anti-CD20 / anti-CD3 bispecific antibody variants that retain some, but not all, effector functions, making them desirable candidates for applications where antibody half-life in vivo is important, but where certain effector functions (such as complement and ADCC) are unnecessary or deleterious. In vitro and / or in vivo cytotoxicity assays can be performed to confirm reduced / depleted CDC and / or ADCC activity. For example, Fc receptor (FcR) binding assays can be performed to ensure that the antibody lacks FcgR binding (and thus likely lacks ADCC activity) but retains FcRn binding ability. NK cells, the primary cells for mediating ADCC, express only Fc(RIII, whereas monocytes express Fc(RI, Fc(RII, and Fc(RIII). FcR expression on hematopoietic cells is summarized in Table 3 on page 464 of Ravetch and Kinet, Annu. Rev. Immunol. 9:457-492 (1991). Non-limiting examples of in vitro assays to assess ADCC activity of a molecule of interest include those described in U.S. Pat. No. 5,500,362 (see, e.g., Hellstrom, I. et al. Proc. Natl Acad. Sci. USA 83:7059-7063 (1986)) and Hellstrom, I. et al., Proc. Natl Acad. Sci. USA 82:1499-1502 (1985); 5,821,337 (see Bruggemann, M. et al., Proc. Natl Acad. Sci. USA 82:1499-1502 (1985); al., J. Exp. Med. 166:1351-1361 (1987). Alternatively, non-radioactive assay methods may be used (see, e.g., ACTI™ non-radioactive cytotoxicity assay for flow cytometry (CellTechnology, Inc., Mountain View, Calif.; and CYTOTOX 96® non-radioactive cytotoxicity assay (PROMEGA®, Madison, Wis.)). Effector cells useful for such assays include peripheral blood mononuclear cells (PBMC) and natural killer (NK) cells.Alternatively or additionally, the ADCC activity of the molecule of interest can be assessed in vivo, for example in an animal model as disclosed in Clynes et al. Proc. Natl Acad. Sci. USA 95:652-656 (1998). C1q binding assays can also be performed to confirm that the antibody is unable to bind C1q and thus lacks CDC activity. See, for example, C1q and C3c binding ELISAs in WO 2006 / 029879 and WO 2005 / 100402. To assess complement activation, a CDC assay may be performed (see, e.g., Gazzano-Santoro et al. J. Immunol. Methods 202:163 (1996); Cragg, MS et al. Blood. 101:1045-1052 (2003); and Cragg, MS and MJ Glennie Blood. 103:2738-2743 (2004)). FcRn binding and in vivo clearance / half-life determinations can also be performed using methods known in the art (see, e.g., Petkova, SB et al. Int'l. Immunol. 18(12):1759-1769 (2006)).

[0214]

[0233] Antibodies with reduced effector function include antibodies with substitutions at one or more of Fc region residues 238, 265, 269, 270, 297, 327, and 329 (U.S. Patent Nos. 6,737,056 and 8,219,149). Such Fc variants include Fc variants with substitutions at two or more of amino acid positions 265, 269, 270, 297, and 327, including the so-called "DANA" Fc variant in which residues 265 and 297 are substituted with alanine (U.S. Patent Nos. 7,332,581 and 8,219,149).

[0215]

[0234] In certain instances, the proline at position 329 of the wild-type human Fc region in the antibody is substituted with an amino acid residue large enough to disrupt the proline sandwich in the Fc / Fc.gamma receptor interface formed between proline 329 of Fc and tryptophan residues Trp87 and Trp110 of FcgRIII, or with glycine or arginine (Sondermann et al.: Nature 406, 267-273 (20 Jul. 2000)). In certain instances, the antibody comprises at least one additional amino acid substitution. In one example, the additional amino acid substitution is S228P, E233P, L234A, L235A, L235E, N297A, N297D, or P331S; in yet another example, the at least one additional amino acid substitution is L234A and L235A in a human IgG1 Fc region, or S228P and L235E in a human IgG4 Fc region (see, e.g., U.S. Patent Application Publication No. 2012 / 0251531); and in yet another example, the at least one additional amino acid substitution is L234A and L235A and P329G in a human IgG1 Fc region.

[0216] Certain antibody variants have been described with improved or diminished binding to FcRs (see, e.g., U.S. Pat. No. 6,737,056; WO 2004 / 056312; and Shields et al., J. Biol. Chem. 9(2):6591-6604 (2001)).

[0236] In certain examples, the antibody variant comprises an Fc region with one or more amino acid substitutions that improve ADCC, e.g., substitutions at positions 298, 333, and / or 334 (EU numbering of residues) of the Fc region.

[0217]

[0237] In some instances, alterations are made in the Fc region that result in altered (i.e., either improved or decreased) C1q binding and / or complement dependent cytotoxicity (CDC), e.g., as described in U.S. Pat. No. 6,194,551, WO 99 / 51642, and Idusogie et al. J. Immunol. 164:4178-4184 (2000).

[0218]

[0238] Antibodies with increased half-lives and improved binding to the neonatal Fc receptor (FcRn), which is responsible for transfer of maternal IgG to the fetus (Guyer et al., J. Immunol. 117:587 (1976) and Kim et al., J. Immunol. 24:249 (1994)), have been described in U.S. Patent Application Publication No. 2005 / 0014934A1 (Hinton et al.). These antibodies comprise an Fc region with one or more substitutions therein that improve binding of the Fc region to FcRn. Such Fc variants include variants having a substitution at one or more of Fc region residues: 238, 256, 265, 272, 286, 303, 305, 307, 311, 312, 317, 340, 356, 360, 362, 376, 378, 380, 382, ​​413, 424 or 434, for example, a substitution at Fc region residue 434 (U.S. Patent No. 7,371,826).

[0219]

[0239] For other examples of Fc region variants, see also Duncan & Winter, Nature 322:738-40 (1988), U.S. Patent No. 5,648,260, U.S. Patent No. 5,624,821, and WO 94 / 29351.

[0220]

[0240] In some embodiments, the anti-CD20 / anti-CD3 bispecific antibody comprises an Fc region that comprises a N297G mutation (EU numbering).

[0221]

[0241] In some examples, the anti-CD20 / anti-CD3 bispecific antibody comprises one or more heavy chain constant domains, the one or more heavy chain constant domains being selected from a first CH1 (CH11) domain, a first CH2 (CH21) domain, a first CH3 (CH31) domain, a second CH1 (CH12) domain, a second CH2 (CH22) domain, and a second CH3 (CH32) domain. In some examples, at least one of the one or more heavy chain constant domains is paired with another heavy chain constant domain. In some examples, the CH31 domain and the CH32 domain each comprise a protrusion or a cavity, and the protrusion or cavity in the CH31 domain can be positioned within the cavity or protrusion in the CH32 domain, respectively. In some examples, the CH31 domain and the CH32 domain meet at the interface between the protrusion and the cavity. In some examples, the CH21 domain and the CH22 domain each comprise a protrusion or a cavity, and the protrusion or cavity in the CH21 domain is positionable within the cavity or protrusion in the CH22 domain, respectively. In other examples, the CH21 domain and the CH22 domain meet at an interface between the protrusion and the cavity. In some examples, the anti-CD20 / anti-CD3 bispecific antibody is an IgG1 antibody.

[0222]

[0242] d. Cysteine ​​Engineered Antibody Variants

[0243] In certain instances, it is desirable to generate cysteine ​​engineered anti-CD20 / anti-CD3 bispecific antibodies, e.g., "thioMAbs," in which one or more residues of the antibody are replaced with cysteine ​​residues. In certain instances, the replaced residues occur at accessible sites of the antibody. By replacing those residues with cysteine, reactive thiol groups are positioned at accessible sites of the antibody, which can be used to conjugate the antibody to other moieties, such as drug moieties or linker-drug moieties, to generate immunoconjugates, as further described herein. In certain instances, any one or more of the following residues are replaced with cysteine: V205 (Kabat numbering) of the light chain; A118 (EU numbering) of the heavy chain; and S400 (EU numbering) of the heavy chain Fc region. Cysteine ​​engineered antibodies can be generated, for example, as described in U.S. Pat. No. 7,521,541.

[0223]

[0244] e. Antibody derivative

[0245] In certain instances, the anti-CD20 / anti-CD3 bispecific antibodies provided herein are further modified to include additional non-proteinaceous moieties that are known in the art and readily available. Moieties suitable for derivatization of antibodies include, but are not limited to, water-soluble polymers. Non-limiting examples of water-soluble polymers include, but are not limited to, polyethylene glycol (PEG), ethylene glycol / propylene glycol copolymers, carboxymethylcellulose, dextran, polyvinyl alcohol, polyvinylpyrrolidone, poly-1,3-dioxolane, poly-1,3,6-trioxane, ethylene / maleic anhydride copolymers, polyamino acids (either homopolymers or random copolymers), and dextran or poly(n-vinylpyrrolidone) polyethylene glycol, polypropylene glycol homopolymer, polypropylene oxide / ethylene oxide copolymer, polyoxyethylated polyols (e.g., glycerol), polyvinyl alcohol, and mixtures thereof. Polyethylene glycol propionaldehyde may have advantages during manufacturing due to its stability in water. The polymer may be of any molecular weight, and may be branched or unbranched. The number of polymers attached to the antibody may vary, and when multiple polymers are attached, the polymers may be the same or different molecules. In general, the number and / or type of polymers used for derivatization may be determined based on considerations including, but not limited to, the particular property or function of the antibody to be improved, whether the antibody derivative will be used under defined conditions, etc.

[0224]

[0246] In another example, a conjugate of an antibody and a non-proteinaceous moiety is provided that can be selectively heated by exposure to radiation. In one example, the non-proteinaceous moiety is a carbon nanotube (Kam et al., Proc. Natl. Acad. Sci. USA 102:11600-11605 (2005)). The radiation can be of any wavelength, including but not limited to wavelengths that are not harmful to normal cells but heat the non-proteinaceous moiety to a temperature that kills cells proximal to the antibody-non-proteinaceous moiety.

[0225]

[0247] 7. Recombinant Production Methods

[0248] Anti-CD20 / anti-CD3 bispecific antibodies can be produced using recombinant methods and compositions, for example, as described in US Pat. No. 4,816,567, incorporated herein by reference.

[0226]

[0249] For recombinant production of anti-CD20 / anti-CD3 bispecific antibodies, nucleic acids encoding the antibodies are isolated and inserted into one or more vectors for further cloning and / or expression in host cells. Such nucleic acids can be readily isolated and sequenced using conventional procedures (e.g., by using oligonucleotide probes capable of specifically binding to genes encoding the heavy and light chains of the antibody).

[0227]

[0250] Suitable host cells for cloning or expressing antibody-encoding vectors include prokaryotic or eukaryotic cells as described herein. For example, antibodies can be produced in bacteria, particularly if glycosylation and effector functions are not required. For expression of antibody fragments and polypeptides in bacteria, see, e.g., U.S. Patent Nos. 5,648,237, 5,789,199, and 5,840,523. (See also Charlton, Methods in Molecular Biology, Vol. 248 (BKC Lo, ed., Humana Press, Totowa, NJ, 2003), pp. 245-254, which describes the expression of antibody fragments in E. coli.) After expression, the antibody may be isolated from the bacterial cell paste as a soluble fraction and further purified.

[0228]

[0251] In addition to prokaryotes, eukaryotic microbes such as filamentous fungi or yeast are suitable cloning or expression hosts for antibody-encoding vectors, including fungal and yeast strains that have been "humanized" in their glycosylation pathways to produce antibodies with partial or fully human glycosylation patterns. See Gerngross, Nat. Biotech. 22:1409-1414 (2004) and Li et al., Nat. Biotech. 24:210-215 (2006).

[0229]

[0252] Suitable host cells for the expression of glycosylated antibodies are also derived from multicellular organisms (invertebrates and vertebrates). Examples of invertebrate cells include plant cells and insect cells. Many baculovirus strains have been identified and can be used in conjunction with insect cells, particularly for transfection of Spodoptera frugiperda cells.

[0230] Plant cell cultures can also be used as hosts. See, e.g., U.S. Patent Nos. 5,959,177, 6,040,498, 6,420,548, 7,125,978, and 6,417,429 (PLANTIBODIES FOR PRODUCING ANTIBODIES IN TRANSGENIC PLANTS). TM See (describe the technique).

[0231] Vertebrate cells may also be used as hosts. For example, mammalian cell lines adapted to grow in suspension may be useful. Other examples of useful mammalian host cell lines include SV40 transformed monkey kidney CV1 line (COS-7); human embryonic kidney lines (e.g., 293 or 293 cells as described in Graham et al., J. Gen Virol. 36:59 (1977)); baby hamster kidney cells (BHK); mouse Sertoli cells (e.g., TM4 cells as described in Mather, Biol. Reprod. 23:243-251 (1980)); monkey kidney cells (CV1); African green monkey kidney cells (VERO-76); human cervical carcinoma cells (HELA); canine kidney cells (MDCK); buffalo rat hepatocytes (BRL 3A); human lung cells (W138); human hepatocytes (Hep G2); mouse mammary tumor (MMT 060562); TRI cells, e.g., as described in Mather et al., Annals NYAcad. Sci. 383:44-68 (1982); MRC Other useful mammalian host cell lines include DHFR 5 cells; and FS4 cells. - Chinese hamster ovary (CHO) cells, including CHO cells (Urlaub et al., Proc. Natl. Acad. Sci. USA 77:4216 (1980)); and myeloma cell lines such as Y0, NS0 and Sp2 / 0. For a review of certain mammalian host cells suitable for antibody production, see, e.g., Yazaki and Wu, Methods in Molecular Biology, Vol. 248 (BKC Lo, ed., Humana Press, Totowa, NJ), pp. 255-268 (2003).

[0232] E. Additional Therapeutic Agents

[0255] In some examples, the methods described herein include administering a bispecific anti-CD20 / anti-CD3 antibody in combination with one or more additional therapeutic agents.

[0233]

[0256] In some examples, the one or more additional therapeutic agents may reduce the rate or severity of cytokine release syndrome (CRS). In some examples, the one or more additional therapeutic agents may prevent symptoms associated with CRS. In certain examples, the additional therapeutic agent used to reduce the rate or severity of CRS or prevent symptoms associated with CRS is a corticosteroid (e.g., dexamethasone (CAS#: 50-02-2), prednisone (CAS#: 53-03-2), prednisolone (CAS#: 50-42-8), or methylprednisolone (CAS#: 83-43-2)), or an IL-6R antagonist (e.g., tocilizumab, sarilumab, bovalizumab (ALX-0061), satralizumab (SA-237), and variants thereof). In some examples, the additional therapeutic agent is dexamethasone. In some examples, the additional therapeutic agent is prednisone. In some instances, the additional therapeutic agent is tocilizumab.

[0234]

[0257] In some examples, additional therapeutic agents useful in the present invention include corticosteroids, cyclophosphamide, B cell depletion therapy, and calcineurin inhibitors. Examples of corticosteroids include hydrocortisone, cortisone acetate, prednisolone, dexamethasone, betamethasone, triamcinolone, beclomethasone, methylprednisolone, and prednisone. Exemplary cell depletion therapy includes rituximab, ocrelizumab, ofatumumab, and obinutuzumab. Exemplary calcineurin inhibitors include cyclosporine, tacrolimus, and bocolosporine.

[0235] IV. Pharmaceutical Compositions and Formulations

[0258] Any of the antibodies (e.g., anti-CD20 / anti-CD3 bispecific antibodies) described herein can be used in pharmaceutical compositions and formulations. Pharmaceutical compositions and formulations of the antibodies and / or other agents described herein can be prepared by mixing one, two, or all three agents with the desired purity with one or more optional pharma- ceutically acceptable carriers (Remington's Pharmaceutical Sciences 16th edition, Osol, A. Ed. (1980)) in the form of a lyophilized formulation or an aqueous solution. Pharmaceutically acceptable carriers are typically non-toxic to recipients at the dosages and concentrations employed and include, but are not limited to, buffers, such as phosphates, citrates, and other organic acids; antioxidants including ascorbic acid and methionine; preservatives (e.g., octadecyldimethylbenzylammonium chloride; hexamethonium chloride; benzalkonium chloride; benzethonium chloride; phenol, butyl, or benzyl alcohol; alkyl parabens, such as methylparaben or propylparaben; catechol; resorcinol; cyclohexanol; 3-pentanol; and m-cresol); low molecular weight (about 10 residues) amines, such as ethylparaben, ... Polypeptides (less than 1000 mg); proteins, such as serum albumin, gelatin or immunoglobulins; hydrophilic polymers, such as polyvinylpyrrolidone; amino acids, such as glycine, glutamine, asparagine, histidine, arginine or lysine; monosaccharides, disaccharides and other carbohydrates, including glucose, mannose or dextrin; chelating agents, such as EDTA; sugars, such as sucrose, mannitol, trehalose or sorbitol; counterions, such as sodium, that form salts; metal complexes (e.g., Zn-protein complexes); and / or non-ionic surfactants, such as polyethylene glycol (PEG). Exemplary pharmacologic carriers herein further include interstitial drug dispersing agents, such as soluble neutral active hyaluronidase glycoproteins (sHASEGPs), such as human soluble PH-20 hyaluronidase glycoproteins, such as rHuPH20 (HYLENEX®, Baxter International, Inc.).Certain exemplary sHASEGPs and methods of use, including rHuPH20, are described in U.S. Patent Publication Nos. 2005 / 0260186 and 2006 / 0104968. In one aspect, the sHASEGP is combined with one or more additional glycosaminoglycanases (e.g., chondroitinases).

[0236]

[0259] Exemplary lyophilized antibody formulations are described in U.S. Patent No. 6,267,958. Aqueous antibody formulations include those described in U.S. Patent No. 6,171,586 and WO 2006 / 044908, the latter formulations including a histidine acetate buffer.

[0237]

[0260] The formulations herein may also contain multiple active ingredients as necessary for the particular indication being treated, preferably those with complementary activities that do not adversely affect each other. For example, it may be desirable to further provide additional therapeutic agents (e.g., chemotherapeutic agents, cytotoxic agents, growth inhibitory agents, and / or antihormonal agents, such as those described herein above). Such active ingredients are suitably present in combination in amounts effective for the intended purpose.

[0238]

[0261] The active ingredient may be encapsulated in microcapsules prepared, for example, by coacervation techniques or by interfacial polymerization (e.g., hydroxymethylcellulose or gelatin microcapsules and poly-(methyl methacrylate) microcapsules, respectively), in colloidal drug delivery systems (e.g., liposomes, albumin microspheres, microemulsions, nanoparticles and nanocapsules), or in macroemulsions. Such techniques are disclosed in Remington's Pharmaceutical Sciences 16th edition, Osol, A. Ed. (1980).

[0239]

[0262] Sustained-release preparations may be prepared. Suitable examples of sustained-release preparations include semipermeable matrices of solid hydrophobic polymers containing the antibody, which matrices are in the form of shaped articles, e.g., films, or microcapsules.

[0240]

[0263] Formulations to be used for in vivo administration are generally sterile. Sterility may be readily accomplished, for example, by filtration through sterile filtration membranes.

[0241] V. KITS AND PRODUCTS

[0264] In another aspect of the invention, a kit or article of manufacture is provided that contains materials useful for the treatment, prevention, and / or diagnosis of the above-mentioned disorders. The kit or article of manufacture includes a container and a label or package insert on or associated with the container. Suitable containers include, for example, bottles, vials, syringes, IV solution bags, and the like. The container can be formed from a variety of materials, such as glass or plastic. The container holds the composition by itself or in combination with another composition effective for the treatment, prevention, and / or diagnosis of a condition, and may have a sterile access port (e.g., the container may be a vial with a stopper pierceable by a hypodermic needle). At least one active agent in the composition is an anti-CD20 / anti-CD3 bispecific antibody as described herein. The label or package insert indicates that the composition is used to treat a selected, previously untreated condition (e.g., a previously untreated B-cell proliferative disorder, e.g., high-grade B-cell lymphoma (HGBL) or non-Hodgkin's lymphoma (NHL), e.g., diffuse large B-cell lymphoma (DLBCL)) and further includes information relating to at least one of the dosing regimens described herein. Additionally, the kit or article of manufacture may include a first container in which (a) the composition is placed, the composition comprising an anti-CD20 / anti-CD3 bispecific antibody described herein, and a second container in which (b) the composition is placed, the composition comprising an additional cytotoxic or other therapeutic agent. Alternatively or additionally, the kit or article of manufacture may further include a second (or third) container comprising a pharma- ceutical acceptable buffer, such as bacteriostatic water for injection (BWFI), phosphate buffered saline, Ringer's solution, dextrose solution, and the like. It may further include other materials desirable from a commercial and user standpoint, including other buffers, diluents, filters, needles, and syringes.

[0242]

[0265] In one aspect, the kit comprises (a) a first container comprising mosunetuzumab; and (b) a package insert comprising instructions for providing treatment to a patient with systemic lupus erythematosus, wherein mosunetuzumab is administered subcutaneously and according to a dosing regimen comprising at least a first dosing cycle, wherein the first dosing cycle comprises a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, wherein C1D1 is between about 1.6 mg and about 5 mg and is administered on day 1 of the cycle, and C1D2 is between about 15 mg and about 60 mg and is administered on day 8 of the cycle.

[0243]

[0266] The kit may also contain 1.6 mg of C1D1 and 15 mg of C1D2.

[0244]

[0267] The kit may also contain 1.6 mg of C1D1 and 45 mg of C1D2.

[0245]

[0268] The kit may also contain 1.6 mg of C1D1 and 60 mg of C1D2.

[0246]

[0269] The kit may also contain 5 mg of C1D1 and 15 mg of C1D2.

[0247]

[0270] The kit may also contain 5 mg of C1D1 and 45 mg of C1D2.

[0248]

[0271] The kit may also contain 5 mg of C1D1 and 60 mg of C1D2.

[0249]

[0272] Each dose may be provided in one or more containers. In some embodiments, the kit includes a container of mosunetuzumab sufficient to administer the indicated dose. In other embodiments, the kit includes a container for each dose; for example, a container with mosunetuzumab sufficient to administer C1D1 and another container for C1D2. For example, in an example where the kit provides C1D1 at 5 mg and C1D2 at 60 mg, one container is dedicated to C1D1 and contains mosunetuzumab in an amount sufficient to deliver 5 mg, and a second container contains mosunetuzumab in an amount sufficient to deliver 60 mg.

[0250]

[0273] In some embodiments, the mosunetuzumab is contained within at least one injection device, such as a prefilled syringe or an autoinjector.

[0251]

[0274] Other technical features will be readily apparent to those skilled in the art from the following drawings, specifications, and claims.

[0252] VI. Measurement of changes in systemic lupus erythematosus

[0275] Provided herein is a method for treating a patient with systemic lupus erythematosus by administering an effective amount of mosunetuzumab, a bispecific antibody that binds to CD3 and CD20. In treating a patient, any tool available to a person skilled in the art may be used to evaluate changes in symptoms of systemic lupus erythematosus. The tools may be used alone or in combination. The following are examples of such tools:

[0253]

[0276] One tool is known as the Patient Global Impression of Severity (PGI-S). This is a simple tool, shown in Figure 3, that asks patients to describe the severity of their lupus over the past week by selecting from the categories "none," "mild," "moderate," "severe," and "very severe." A reduction in systemic lupus symptoms is a PGI-S result moving from anything other than "none" toward "none."

[0254]

[0277] Another tool is the Physician Global Assessment (PGA) (Figure 4). The PGA is a visual analog scale from 0 to 10 cm, anchored at 0 (none) and 3 (severe), with a midline at 1 (mild) and 2 (moderate), designed to allow physicians to indicate a subject's overall disease activity at a particular visit (Petri et al. 1999). When assessing a participant's disease activity, the patient's medical history, physical examination results, and appropriate laboratory values ​​are taken into account. Each PGA measurement can be linearly transformed (×3 / 10) to obtain a value between 0.00 and 3.00. A reduction in systemic lupus erythematosus symptoms is a PGA rating moving from "severe (3)" toward "none (0)."

[0255]

[0278] As mentioned above, the change in antinuclear antibody (ANA) titer is often elevated in systemic lupus erythematosus. ANA can be determined using standard assays, including assays using immunofluorescence. In one embodiment, the ANA titer is a positive test of more than or equal to 1:80 in HEp-2 cells, which indicates symptoms of systemic lupus erythematosus. In one embodiment, a decrease in the ANA titer indicates an improvement in systemic lupus erythematosus.

[0256]

[0279] Changes in anti-double stranded DNA (dsDNA) antibody (IgG) titers may also be used. Standard assay methods may be used to detect and quantify dsDNA. In one embodiment, a decrease in dsDNA antibody (IgG) titers indicates improvement of systemic lupus erythematosus.

[0257]

[0280] In patients with systemic lupus erythematosus, the levels of complement C3 and / or complement C4 are often decreased. Changes in these levels can be assessed using standard assays to quantify the changes. An increase in complement C3 and / or complement C4 indicates improvement of systemic lupus erythematosus.

[0258]

[0281] The above list of tools, and others that may be selected by one of skill in the art, may be used and interpreted with reference to an expected average value for a patient. Additionally, changes may be interpreted relative to a baseline established by an initial test or assay. These changes are detected by repeating the same test or assay over time and comparing the resulting values ​​to the observed baseline.

[0259] VII. Implementation

[0282] Embodiment 1. A method of treating a patient, comprising administering to the patient an effective amount of mosunetuzumab, wherein the patient has systemic lupus erythematosus.

[0260]

[0283] Embodiment 2. The method of embodiment 1, wherein the patient is receiving an oral corticosteroid, an antimalarial, or an immunosuppressant prior to receiving the effective amount of mosunetuzumab.

[0261]

[0284] Embodiment 3. The method of embodiment 2, wherein the patient has received a stable dose of at least 40 mg / day of prednisone (or equivalent) for at least 7 days prior to receiving the effective amount of mosunetuzumab.

[0262]

[0285] Embodiment 4. The method of embodiment 2, wherein the patient has received a stable dose of an antimalarial agent for at least 4 weeks prior to receiving the effective amount of mosunetuzumab.

[0263]

[0286] Embodiment 5. The method of embodiment 2, wherein the patient has received a stable dose of an immunosuppressant for at least 4 weeks prior to receiving the effective amount of mosunetuzumab.

[0264]

[0287] Embodiment 6. The method of embodiment 5, wherein the immunosuppressant is azathioprine, mycophenolate mofetil, mycophenolic acid, or methotrexate.

[0265]

[0288] Embodiment 7. The method of embodiment 1, wherein the patient does not have a lupus-associated neuropsychiatric disorder.

[0266]

[0289] Embodiment 8. The method of embodiment 7, wherein the lupus-associated neuropsychiatric disorder is meningitis, retinitis, cerebral vasculitis, myelopathy, demyelinating syndrome, acute confusional state, psychosis, acute stroke or stroke syndrome, cranial neuropathy, status epilepticus or seizures, cerebellar ataxia, or multiple mononeuritis.

[0267]

[0290] Embodiment 9. The method of embodiment 1, wherein the patient does not have an active overlap syndrome with mixed connective tissue disease or systemic sclerosis within one year of receiving an effective amount of mosunetuzumab.

[0268]

[0291] Embodiment 10. The method of claim 1, wherein the patient does not have fulminant or severe antiphospholipid syndrome within one year of receiving an effective amount of mosunetuzumab, except when severe antiphospholipid syndrome has been adequately controlled by administering anticoagulant therapy to a patient who has been receiving an effective amount of mosunetuzumab for at least three months.

[0269]

[0292] Embodiment 11. A patient comprising: (a) At least 12 months prior to receiving an effective amount of mosunetuzumab: (i) anti-CD19 antibody therapy, or (ii) Anti-CD20 monoclonal antibody therapy or (b) At least 30 days prior to receiving an effective amount of mosunetuzumab: (i) a kinase inhibitor of Janus kinase (JAK) kinase, Bruton's tyrosine kinase, or tyrosine kinase 2, or (ii) tacrolimus, cyclosporine, or voclosporin; or (c) For at least 2 months after receiving an effective dose of mosunetuzumab: (i) cyclophosphamide, or (ii) Biological therapy 2. The method of embodiment 1, wherein the patient is not administered

[0270]

[0293] Embodiment 12.(a) the anti-CD19 therapy is blinatumomab; (b) whether the anti-CD20 therapy was obinutuzumab, rituximab, ocrelizumab, or ofatumumab; (c) the kinase inhibitor is baricitinib, tofacitinib, upadacitinib, filgotinib, ibrutinib, or fenebrutinib; or (d) the biologic therapy is belimumab, ustekinumab, anifrolumab, secukinumab, or atacicept; The method of embodiment 11.

[0271]

[0294] Embodiment 13. The method of embodiment 1, wherein the patient does not have significant lupus-related renal disease or significant renal impairment.

[0272]

[0295] Embodiment 14. A patient comprising: (a) total bilirubin >1.5 × ULN; (b) ANC<1.5×10 9 / L(<1500 / mm 3 ), (c) Platelet count<100×10 9 / L(100,000 / mm 3 ), (d) hemoglobin < 100 g / L; (e) estimated glomerular filtration rate (eGFR) < 30 ml / min / 1.73 m calculated according to the Chronic Kidney Disease Epidemiology Collaboration formula 2 , and (f) Positive serum human chorionic gonadotropin The method of claim 1, wherein the clinical test does not include one parameter selected from the group consisting of:

[0273]

[0296] Embodiment 15. The method of embodiment 1, wherein at least one symptom of SLE is reduced.

[0274]

[0297] Embodiment 16. The method of embodiment 15, wherein the reduction in at least one symptom of SLE is measured using Patient Global Impression of Severity (PGI-S), Physician Global Assessment (PGA), a reduction in antinuclear antibody (ANA) titer, a reduction in anti-double stranded DNA (dsDNA) antibody (IgG) titer, an increase in complement C3 levels, or an increase in complement C4 levels.

[0275]

[0298] Embodiment 17. The method of embodiment 16, wherein the reduction in at least one symptom is a change in at least one step response on the PGI-S from a previous response, the change being one of: from "very severe" to "severe", "severe" to "moderate", "moderate" to "mild", or "mild" to "none".

[0276]

[0299] 18. The method of embodiment 16, wherein the reduction in at least one symptom is a change in a rating by a health care provider using a PGA, and the change is a reduction from a rating prior to using the PGA.

[0277]

[0300] Embodiment 19. The method of embodiment 18, wherein the reduction from the previous assessment using a PGA is ≧0.3 points from baseline.

[0278]

[0301] Embodiment 20. The method of claim 1, wherein administering an effective amount of mosunetuzumab comprises administering mosunetuzumab according to a dosing regimen comprising at least a first dosing cycle, the first dosing cycle comprising a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, wherein C1D1 is less than C1D2, C1D1 is between about 1.6 mg and about 5 mg, and C1D2 is between about 15 mg and about 60 mg.

[0279]

[0302] Embodiment 21. The method of embodiment 20, wherein C1D2 is 15 mg, 45 mg, or 60 mg.

[0280]

[0303] Embodiment 22. The method of embodiment 20, wherein the first administration cycle is about 8 days.

[0281]

[0304] Embodiment 23. The method of embodiment 22, wherein the C1D1 dose of mosunetuzumab is administered on about day 1 of the cycle.

[0282]

[0305] Embodiment 24. The method of embodiment 22, wherein the C1D2 dose of mosunetuzumab is administered on about day 8 of the cycle.

[0283]

[0306] Embodiment 25. The method of embodiment 1, wherein mosunetuzumab is administered subcutaneously.

[0284]

[0307] Embodiment 26. The method of embodiment 1, wherein the patient is further administered tocilizumab if the patient experiences cytokine release syndrome (CRS).

[0285]

[0308] Embodiment 27. The method of embodiment 1, further comprising administering to the patient a corticosteroid, cyclophosphamide, B cell depletion therapy, or a calcineurin inhibitor.

[0286]

[0309] Embodiment 28. The method of embodiment 27, wherein the corticosteroid comprises hydrocortisone, cortisone acetate, prednisolone, dexamethasone, betamethasone, triamcinolone, beclomethasone, methylprednisolone or prednisone; the B cell depletion therapy comprises administering rituximab, ocrelizumab, ofatumumab, or obinutuzumab, or the calcineurin inhibitor comprises cyclosporine, tacrolimus, or bocolosporine.

[0287]

[0310] Embodiment 29. The method of embodiment 16, wherein the ANA is an initial titer of 1:80 or greater in a positive test on HEp-2 cells or equivalent.

[0288]

[0311] Embodiment 30. The method of embodiment 16, wherein the ANA is a titer of less than 1:80 in a positive test on HEp-2 cells or equivalent.

[0289]

[0312] Embodiment 31. A method of treating a patient, comprising administering to the patient an effective amount of mosunetuzumab, (a) the patient has systemic lupus erythematosus; (b) mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, the first dosing cycle comprising a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, wherein C1D1 is between about 1.6 mg and about 5 mg on day 1 of the cycle and C1D2 is between about 15 mg and about 60 mg on day 8 of the cycle; (c) Mosunetuzumab is administered subcutaneously; method.

[0290]

[0313] Embodiment 32. The method of embodiment 31, wherein C1D1 is 1.6 mg.

[0291]

[0314] Embodiment 33. The method of embodiment 31, wherein C1D1 is 5 mg.

[0292]

[0315] Embodiment 34. The method of embodiment 31, wherein C1D2 is 15 mg.

[0293]

[0316] Embodiment 35. The method of embodiment 31, wherein C1D2 is 45 mg.

[0294]

[0317] Embodiment 36. The method of embodiment 31, wherein C1D2 is 60 mg.

[0295]

[0318] Embodiment 37. The method according to embodiment 31, wherein C1D1 is 1.6 mg and C1D2 is 15 mg.

[0296]

[0319] Embodiment 38. The method according to embodiment 31, wherein C1D1 is 1.6 mg and C1D2 is 45 mg.

[0297]

[0320] Embodiment 39. The method according to embodiment 31, wherein C1D1 is 1.6 mg and C1D2 is 60 mg.

[0298]

[0321] Embodiment 40. The method according to embodiment 31, wherein C1D1 is 5 mg and C1D2 is 15 mg.

[0299]

[0322] Embodiment 41. The method according to embodiment 31, wherein C1D1 is 5 mg and C1D2 is 45 mg.

[0300]

[0323] Embodiment 42. The method according to embodiment 31, wherein C1D1 is 5 mg and C1D2 is 60 mg.

[0301]

[0324] Embodiment 43. The method of embodiment 31, wherein at least one symptom of SLE is reduced.

[0302]

[0325] Embodiment 44. The method of embodiment 43, wherein the reduction in at least one symptom of SLE is measured using Patient Global Impression of Severity (PGI-S), Physician Global Assessment (PGA), a reduction in antinuclear antibody (ANA) titer, a reduction in anti-double stranded DNA (dsDNA) antibody (IgG) titer, an increase in complement C3 levels, or an increase in complement C4 levels.

[0303]

[0326] Embodiment 45. The method of embodiment 44, wherein the reduction in at least one symptom is a change in at least one step response on the PGI-S from a previous response, the change being one of: from "very severe" to "severe", "severe" to "moderate", "moderate" to "mild", or "mild" to "none".

[0304]

[0327] 46. ​​The method of embodiment 44, wherein the reduction in at least one symptom is a change in a rating by a health care provider using a PGA, and the change is a reduction from a rating prior to using the PGA.

[0305]

[0328] Embodiment 47. The method of embodiment 46, wherein the reduction from the previous assessment using a PGA is ≧0.3 points from baseline.

[0306]

[0329] Embodiment 48. The method of embodiment 31, wherein mosunetuzumab is administered subcutaneously.

[0307]

[0330] Embodiment 49. The method of embodiment 31, wherein the patient is further administered tocilizumab if the patient experiences cytokine release syndrome (CRS).

[0308]

[0331] Embodiment 50. The method of embodiment 31, further comprising administering to the patient a corticosteroid, cyclophosphamide, B cell depletion therapy, or a calcineurin inhibitor.

[0309]

[0332] Embodiment 51. The method of embodiment 50, wherein the corticosteroid comprises hydrocortisone, cortisone acetate, prednisolone, dexamethasone, betamethasone, triamcinolone, beclomethasone, methylprednisolone or prednisone; the B cell depletion therapy comprises administering rituximab, ocrelizumab, ofatumumab, or obinutuzumab, or the calcineurin inhibitor comprises cyclosporine, tacrolimus, or bocolosporine.

[0310]

[0333] Embodiment 52. The method of embodiment 44, wherein the ANA is an initial titer of 1:80 or greater in a positive test on HEp-2 cells or equivalent.

[0311]

[0334] Embodiment 53. The method of embodiment 44, wherein the ANA is a titer of less than 1:80 in a positive test on HEp-2 cells or equivalent.

[0312]

[0335] Embodiment 54. A method of treating patients who are part of a patient population, comprising administering to the patients an effective amount of mosunetuzumab, wherein each patient of the patient population has systemic lupus erythematosus.

[0313]

[0336] Embodiment 55. The method of embodiment 54, wherein the patient is receiving an oral corticosteroid, an antimalarial, or an immunosuppressant prior to receiving the effective amount of mosunetuzumab.

[0314]

[0337] Embodiment 56. The method of embodiment 55, wherein the patient has received a stable dose of at least 40 mg / day of prednisone (or equivalent) for at least 7 days prior to receiving the effective amount of mosunetuzumab.

[0315]

[0338] Embodiment 57. The method of embodiment 55, wherein the patient has received a stable dose of an antimalarial agent for at least 4 weeks prior to receiving the effective amount of mosunetuzumab.

[0316]

[0339] Embodiment 58. The method of embodiment 55, wherein the patient has received a stable dose of an immunosuppressant for at least 4 weeks prior to receiving an effective amount of mosunetuzumab.

[0317]

[0340] Embodiment 59. The method of embodiment 58, wherein the immunosuppressant is azathioprine, mycophenolate mofetil, mycophenolic acid, or methotrexate.

[0318]

[0341] Embodiment 60. The method of embodiment 54, wherein the patient does not have a lupus-associated neuropsychiatric disorder.

[0319]

[0342] Embodiment 61. The method of embodiment 60, wherein the lupus-associated neuropsychiatric disorder is meningitis, retinitis, cerebral vasculitis, myelopathy, demyelinating syndrome, acute confusional state, psychosis, acute stroke or stroke syndrome, cranial neuropathy, status epilepticus or seizures, cerebellar ataxia, or multiple mononeuritis.

[0320]

[0343] Embodiment 62. The method of embodiment 54, wherein the patient does not have an active overlap syndrome with mixed connective tissue disease or systemic sclerosis within one year of receiving an effective amount of mosunetuzumab.

[0321]

[0344] Embodiment 63. The method of embodiment 54, wherein the patient does not have fulminant or severe antiphospholipid syndrome within one year of being administered an effective amount of mosunetuzumab, except in cases where severe antiphospholipid syndrome has been adequately controlled by administering anticoagulant therapy to a patient who has been administered an effective amount of mosunetuzumab for at least 3 months.

[0322]

[0345] Embodiment 64. A patient comprising: (a) At least 12 months prior to receiving an effective amount of mosunetuzumab: (i) anti-CD19 antibody therapy, or (ii) Anti-CD20 monoclonal antibody therapy or (b) At least 30 days prior to receiving an effective amount of mosunetuzumab: (i) a kinase inhibitor of Janus kinase (JAK) kinase, Bruton's tyrosine kinase, or tyrosine kinase 2, or (ii) tacrolimus, cyclosporine, or voclosporin; or (c) For at least 2 months after receiving an effective dose of mosunetuzumab: (i) cyclophosphamide, or (ii) Biological therapy 55. The method of embodiment 54, wherein the patient is not administered

[0323]

[0346] Embodiment 65. (a) the anti-CD19 therapy is blinatumomab; (b) whether the anti-CD20 therapy was obinutuzumab, rituximab, ocrelizumab, or ofatumumab; (c) the kinase inhibitor is baricitinib, tofacitinib, upadacitinib, filgotinib, ibrutinib, or fenebrutinib; or (d) the biologic therapy is belimumab, ustekinumab, anifrolumab, secukinumab, or atacicept; The method of embodiment 64.

[0324]

[0347] Embodiment 66. The method according to embodiment 54, wherein the patient does not have significant lupus-related renal disease or significant renal impairment.

[0325]

[0348] Embodiment 67. A patient comprising: (a) total bilirubin >1.5 × ULN; (b) ANC<1.5×10 9 / L(<1500 / mm 3 ), (c) Platelet count<100×10 9 / L(100,000 / mm 3 ), (d) hemoglobin < 100 g / L; (e) estimated glomerular filtration rate (eGFR) < 30 ml / min / 1.73 m calculated according to the Chronic Kidney Disease Epidemiology Collaboration formula 2 , and (f) Positive serum human chorionic gonadotropin 55. The method of claim 54, wherein the assay does not include one clinical test parameter selected from the group consisting of:

[0326]

[0349] Embodiment 68. The method of embodiment 54, wherein at least one symptom of SLE is reduced in at least one patient in the patient population.

[0327]

[0350] Embodiment 69. The method of embodiment 68, wherein the reduction in at least one symptom of SLE is measured using Patient Global Impression of Severity (PGI-S), Physician Global Assessment (PGA), a reduction in antinuclear antibody (ANA) titer, a reduction in anti-double stranded DNA (dsDNA) antibody (IgG) titer, an increase in complement C3 levels, or an increase in complement C4 levels.

[0328]

[0351] Embodiment 70. The method of embodiment 69, wherein the reduction in at least one symptom is a change in at least one step response on the PGI-S from a previous response, the change being one of the following: from "very severe" to "severe", "severe" to "moderate", "moderate" to "mild", or "mild" to "none".

[0329]

[0352] 71. The method of embodiment 69, wherein the reduction in at least one symptom is a change in a rating by a health care provider using a PGA, and the change is a reduction from a rating prior to using the PGA.

[0330]

[0353] Embodiment 72. The method of embodiment 71, wherein the reduction from the previous assessment using a PGA is ≧0.3 points from baseline.

[0331]

[0354] Embodiment 73. The method of claim 54, wherein administering an effective amount of mosunetuzumab comprises administering mosunetuzumab according to a dosing regimen comprising at least a first dosing cycle, the first dosing cycle comprising a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, wherein C1D1 is less than C1D2, C1D1 is between about 1.6 mg and about 5 mg, and C1D2 is between about 15 mg and about 60 mg.

[0332]

[0355] Embodiment 74. The method of embodiment 73, wherein C1D2 is 15 mg, 45 mg, or 60 mg.

[0333]

[0356] Embodiment 75. The method of embodiment 73, wherein the first administration cycle is about 8 days.

[0334]

[0357] Embodiment 76. The method of embodiment 75, wherein the C1D1 dose of mosunetuzumab is administered on about day 1 of the cycle.

[0335]

[0358] Embodiment 77. The method according to embodiment 75, wherein the C1D2 dose of mosunetuzumab is administered on about day 8 of the cycle.

[0336]

[0359] Embodiment 78. The method according to embodiment 54, wherein mosunetuzumab is administered subcutaneously.

[0337]

[0360] Embodiment 79. The method of embodiment 54, wherein the patient is further administered tocilizumab if the patient experiences cytokine release syndrome (CRS).

[0338]

[0361] Embodiment 80. The method of embodiment 54, further comprising administering to the patient a corticosteroid, cyclophosphamide, B cell depletion therapy, or a calcineurin inhibitor.

[0339]

[0362] Embodiment 81. The method of embodiment 80, wherein the corticosteroid comprises hydrocortisone, cortisone acetate, prednisolone, dexamethasone, betamethasone, triamcinolone, beclomethasone, methylprednisolone or prednisone; the B cell depletion therapy comprises administering rituximab, ocrelizumab, ofatumumab, or obinutuzumab, or the calcineurin inhibitor comprises cyclosporine, tacrolimus, or bocolosporine.

[0340]

[0363] Embodiment 82. The method of embodiment 69, wherein the ANA is an initial titer of 1:80 or greater in a positive test on HEp-2 cells or equivalent.

[0341]

[0364] Embodiment 83. The method of embodiment 69, wherein the ANA is a titer of less than 1:80 in a positive test on HEp-2 cells or equivalent.

[0342]

[0365] Embodiment 84. A method of treating a patient from a patient population, comprising administering to the patient an effective amount of mosunetuzumab, (a) the patient population has systemic lupus erythematosus; (b) mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, the first dosing cycle comprising a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, wherein C1D1 is between about 1.6 mg and about 5 mg on day 1 of the cycle and C1D2 is between about 15 mg and about 60 mg on day 8 of the cycle; (c) Mosunetuzumab is administered subcutaneously; method.

[0343]

[0366] Embodiment 85. The method of embodiment 84, wherein C1D1 is 1.6 mg.

[0344]

[0367] Embodiment 86. The method of embodiment 84, wherein C1D1 is 5 mg.

[0345]

[0368] Embodiment 87. The method of embodiment 84, wherein C1D2 is 15 mg.

[0346]

[0369] Embodiment 88. The method of embodiment 84, wherein C1D2 is 45 mg.

[0347]

[0370] Embodiment 89. The method of embodiment 84, wherein C1D2 is 60 mg.

[0348]

[0371] Embodiment 90. The method according to embodiment 84, wherein C1D1 is 1.6 mg and C1D2 is 15 mg.

[0349]

[0372] Embodiment 91. The method according to embodiment 84, wherein C1D1 is 1.6 mg and C1D2 is 45 mg.

[0350]

[0373] Embodiment 92. The method according to embodiment 84, wherein C1D1 is 1.6 mg and C1D2 is 60 mg.

[0351]

[0374] Embodiment 93. The method according to embodiment 84, wherein C1D1 is 5 mg and C1D2 is 15 mg.

[0352]

[0375] Embodiment 94. The method according to embodiment 84, wherein C1D1 is 5 mg and C1D2 is 45 mg.

[0353]

[0376] Embodiment 95. The method according to embodiment 84, wherein C1D1 is 5 mg and C1D2 is 60 mg.

[0354]

[0377] Embodiment 96. The method of embodiment 84, wherein at least one symptom of SLE is reduced.

[0355]

[0378] Embodiment 97. The method of embodiment 96, wherein the reduction in at least one symptom of SLE is measured using Patient Global Impression of Severity (PGI-S), Physician Global Assessment (PGA), a reduction in antinuclear antibody (ANA) titer, a reduction in anti-double stranded DNA (dsDNA) antibody (IgG) titer, an increase in complement C3 levels, or an increase in complement C4 levels.

[0356]

[0379] Embodiment 98. The method of embodiment 97, wherein the reduction in at least one symptom is a change in the response of at least one step on the PGI-S from a previous response, the change being one of the following: from "very severe" to "severe", "severe" to "moderate", "moderate" to "mild", or "mild" to "none".

[0357]

[0380] 99. The method of embodiment 97, wherein the reduction in at least one symptom is a change in a rating by a health care provider using a PGA, and the change is a reduction from a rating prior to using the PGA.

[0358]

[0381] Embodiment 100. The method of embodiment 99, wherein the reduction from the previous assessment using a PGA is ≧0.3 points from baseline.

[0359]

[0382] Embodiment 101. The method according to embodiment 84, wherein mosunetuzumab is administered subcutaneously.

[0360]

[0383] Embodiment 102. The method of embodiment 84, wherein the patient is further administered tocilizumab if the patient experiences cytokine release syndrome (CRS).

[0361]

[0384] Embodiment 103. The method of embodiment 84, further comprising administering to the patient a corticosteroid, cyclophosphamide, B cell depletion therapy, or a calcineurin inhibitor.

[0362]

[0385] Embodiment 104. The method of embodiment 103, wherein the corticosteroid comprises hydrocortisone, cortisone acetate, prednisolone, dexamethasone, betamethasone, triamcinolone, beclomethasone, methylprednisolone or prednisone; the B cell depletion therapy comprises administering rituximab, ocrelizumab, ofatumumab, or obinutuzumab, or the calcineurin inhibitor comprises cyclosporine, tacrolimus, or bocolosporine.

[0363]

[0386] Embodiment 105. The method of embodiment 97, wherein the ANA is an initial titer of 1:80 or greater in a positive test on HEp-2 cells or equivalent.

[0364]

[0387] Embodiment 106. The method of embodiment 97, wherein the ANA is a titer of less than 1:80 in a positive test on HEp-2 cells or equivalent.

[0365]

[0388] Embodiment 107. A kit comprising: (a) a first container containing mosunetuzumab; (b) a package insert comprising instructions for providing treatment to a patient with systemic lupus erythematosus, wherein mosunetuzumab is administered subcutaneously and according to a dosing regimen comprising at least a first dosing cycle, the first dosing cycle comprising a first dose (C1D1) and a second dose (C1D2) of mosunetuzumab, wherein C1D1 is between about 1.6 mg and about 5 mg and is administered on day 1 of the cycle, and C1D2 is between about 15 mg and about 60 mg and is administered on day 8 of the cycle; and Including the kit.

[0366]

[0389] Embodiment 108. A kit according to embodiment 107, wherein C1D1 is 1.6 mg and C1D2 is 15 mg.

[0367]

[0390] Embodiment 109. A kit according to embodiment 107, wherein C1D1 is 1.6 mg and C1D2 is 45 mg.

[0368]

[0391] Embodiment 110. A kit according to embodiment 107, wherein C1D1 is 1.6 mg and C1D2 is 60 mg.

[0369]

[0392] Embodiment 111. The kit described in embodiment 107, wherein C1D1 is 5 mg and C1D2 is 15 mg.

[0370]

[0393] Embodiment 112. The kit according to embodiment 107, wherein C1D1 is 5 mg and C1D2 is 45 mg.

[0371]

[0394] Embodiment 113. The kit according to embodiment 107, wherein C1D1 is 5 mg and C1D2 is 60 mg.

[0372]

[0395] Embodiment 114. The kit according to embodiment 107, wherein the mosunetuzumab is contained within an injection device.

[0373]

[0396] Embodiment 115. The kit according to embodiment 114, wherein the injection device is a syringe or an automatic injector.

[0374]

[0397] Embodiment 116. The kit described in embodiment 107, further comprising a second container.

[0375]

[0398] Embodiment 117. The kit described in embodiment 116, wherein the first container includes an injection device containing sufficient mosunetuzumab to deliver a first dose, and the second container includes an injection device containing sufficient mosunetuzumab to deliver a second dose.

[0376]

[0399] Embodiment 118. The kit described in embodiment 116, further comprising at least a third container.

[0377]

[0400] Embodiment 119. The kit described in embodiment 118, wherein the third container contains a medicament and the instructions further provide instructions for administering the medicament.

[0378]

[0401] Embodiment 120. The kit of embodiment 119, wherein the medicament comprises a corticosteroid, cyclophosphamide, B cell depletion therapy, or a calcineurin inhibitor.

[0379]

[0402] Embodiment 121. The kit of embodiment 120, wherein the corticosteroid comprises hydrocortisone, cortisone acetate, prednisolone, dexamethasone, betamethasone, triamcinolone, beclomethasone, methylprednisolone or prednisone; the B cell depletion therapy comprises rituximab, ocrelizumab, ofatumumab, or obinutuzumab, and the calcineurin inhibitor comprises cyclosporine, tacrolimus, or bocolosporine. EXAMPLES

[0380] VIII. Examples

[0403] The following examples are not to be construed as limiting the invention in any way.

[0381] Example 1. Study rationale and benefit-risk assessment (desk)

[0404] The objective of this Phase 1b study is to evaluate the safety and tolerability, pharmacokinetics, and pharmacodynamics of escalating doses of mosunetuzumab in patients with SLE to inform dose selection for subsequent studies of mosunetuzumab in patients with lupus nephritis (LN) and extrarenal SLE, as well as studies in other autoimmune diseases.

[0382]

[0405] B cells play an active role in the pathogenesis of SLE. Autoreactive B cells recognize and present self-antigens, produce autoantibodies, secrete inflammatory cytokines, and participate in T cell costimulation. For this reason, autoreactive B cells are an attractive therapeutic target for SLE, but numerous trials evaluating agents targeting B cells, B cell activation, or B cell survival factors have failed, including randomized controlled trials of the type I anti-CD20 monoclonal antibody rituximab for the treatment of SLE (study U2971g [EXPLORER]) and severe LN (study U2970g [LUNAR]). These past failures may be due in part to B cell dysregulation in SLE associated with resistance to depletion (Yap 2019). Recently, an association between the degree and duration of B cell depletion in SLE, particularly in LNs, and the degree of clinical benefit has been demonstrated in multiple cohorts, giving rise to the hypothesis that higher levels of B cell depletion may be necessary to achieve efficacy (Md Yusof et al. 2017; Gomez Mendez et al. 2018; Furie et al. 2020).

[0383]

[0406] This hypothesis was the rationale for testing mosunetuzumab in the treatment of SLE: compared with other anti-CD20 molecules, mosunetuzumab, based on a T cell-dependent mechanism, may be able to kill tissue-infiltrating B cells more extensively and kill cells with very low levels of CD20 expression more efficiently, thereby allowing a greater degree of B cell depletion and therefore improved efficacy.

[0384]

[0407] Overall, the nonclinical data and data from prior and ongoing clinical trials in oncology indications support the initiation of this Phase 1b study in participants with SLE. Potential safety issues associated with administration of mosunetuzumab are expected to be clinically monitorable and manageable, and measures are being taken to avoid or minimize such toxicities in the study.

[0385]

[0408] According to its currently known mechanism of action, mosunetuzumab simultaneously binds to CD3 on T cells and CD20 on B cells, leading to T cell activation and subsequent T cell-mediated killing of B cells. The proposed clinical starting dose, maximum clinical dose, and SC administration route of mosunetuzumab were selected based on several factors, including currently available safety and efficacy data from oncology clinical trials, the molecular properties of mosunetuzumab, its mechanism of action, and nonclinical safety data in cynomolgus monkeys.

[0386]

[0409] Based on currently available clinical safety data and benefit-risk considerations for the patient population in this study, the first mosunetuzumab dose to be tested is 1.6 mg SC, a pharmacologically active dose level previously determined to be safe and tolerated in humans in an SC formulation (Study GO29781, Group D). The dose escalation factor from cohort to cohort is approximately 3-fold (see 3.1 and Figure 1 for dose titration and dose escalation doses).

[0387]

[0410] CRS is the main acute toxicity of concern and is associated with cytokine exposure. Baseline circulating B- and T-cell counts may provide information about potential CRS risk. Currently available clinical data suggest that baseline B- and T-cell count ranges in patients with SLE (Study U2971g) are similar to those seen in patients with previously untreated B-cell non-Hodgkin lymphoma (NHL) (Study GO29044) and elderly patients with previously untreated diffuse large B-cell lymphoma (Cohort B) compared with patients with relapsed or refractory (R / R) B-cell NHL (Study GO29365), suggesting a lower risk of CRS. In the phase I / II study GO40554 (cohort B, n=40) in older patients with previously untreated diffuse large B-cell lymphoma, IV mosunetuzumab showed a tolerable safety profile: in the 1 / 2 / 13.5 mg cohort (1 mg on day 1 of cycle 1, 2 mg on day 8 of cycle 1, 13.5 mg on day 15 of cycle 1, followed by 13.5 mg on day 1 of subsequent cycles (Q3W)), 25% of participants had grade 1 CRS, and in the 1 / 2 / 30 mg cohort (CCOD, 15 January 2021), 12.5% ​​had grade 1 and 9.4% had grade 2. SC administration may help reduce the risk of CRS compared to IV administration due to a reduction in the maximum concentration (Cmax) observed in serum associated with CRS, while the area under the concentration-time curve (AUC) remains comparable. SC administration of mosunetuzumab is currently being investigated in study GO29781 in patients with R / R non-Hodgkin lymphoma, which also showed a tolerable safety profile. In a recent analysis of group D (SC fixed-dose escalation) of this study (Matasar et al. 2020), participants received single-agent mosunetuzumab every 3 weeks (Q3W) for 8 cycles. As of January 23, 2021, 48 participants had received SC mosunetuzumab at a fixed dose between 1.6 mg and 20 mg. CRS occurred in 29.2% (n=14) of participants.Most CRS events (graded according to the ASTCT Consensus Grading Criteria (Lee et al. 2019)) occurred during cycle 1 (93%), and all events were grade 1 (n=11, 22.9%) or grade 2 (n=3, 6.3%). In participants receiving SC mosunetuzumab, one CRS event was treated with tocilizumab and two participants were treated with low-flow oxygen. No intensive care unit admission or use of high-flow oxygen or vasopressors was required. Of note, the SC formulation of mosunetuzumab had a lower frequency of grade 2 CRS events than the IV fixed-dose group, despite the dose level being 7-fold higher. The data suggest a manageable safety profile of mosunetuzumab SC doses of 1.6–20 mg in patients with R / R NHL (see mosunetuzumab investigator's brochure). Step-up split dosing may further minimize the rate and severity of CRS events by decreasing Cmax while maintaining AUC. A step-up dosing regimen is being evaluated in Group F of study GO29781 in patients with NHL. As of January 23, 2021, the first 5 / 15 / 45mg cohort (Cycle 1 of 5 / 15 / 45mg, step-up doses on days 1 / 8 / 15, respectively, followed by Q3W dosing) has been cleared and the maximum tolerated dose (MTD) was not reached. Of the eight participants treated with step-up 5 / 15 / 45mg SC mosunetuzumab in cycle 1, CRS was reported in three patients (37.5%). All were grade 1 (n=1, 12.5%) or grade 2 (n=2, 25.0%). Two participants treated with tocilizumab required oxygen support, vasopressors, or intensive care unit admission. Maximum IV step-up clinical doses of 1 / 2 / 60 mg have been tested in cancer patients. To further support a maximum dose level of 60 mg, an exploratory quantitative systems pharmacology (QSP) model was used to simulate the time course of systemic B cell dynamics for 60 days after administration of mosunetuzumab.Systemic B cell depletion and rebound in the QSP model was implemented and validated based on preclinical data of mosunetuzumab in cynomolgus monkeys (Hosseini et al.). To predict the dynamics of circulating B cells in SLE patients, the model representation was first converted from cynomolgus monkeys to humans by changing the physiological parameters (i.e., tissue compartment volumes and cell numbers in each compartment) and the PK properties of mosunetuzumab to human values. Secondly, baseline circulating B and T cells of SLE patients obtained from study U2971g were applied to the peripheral blood compartment. Model-based simulations of planned doses up to 60 mg suggested a dose-dependent increase in the duration of B cell depletion (<5 cells / μL), with more than 90% of simulated patients able to maintain B cell depletion after 60 days at 60 mg.

[0388] Example 2. Objectives and Endpoints (Decorative)

[0411] This clinical trial is designed to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of mosunetuzumab in participants with systemic lupus erythematosus. For exploratory activity objectives, the clinical response of mosunetuzumab in patients with SLE was evaluated based on the following endpoints:

[0389]

[0412] 2.1 Primary safety goals

[0413] The safety objective of the study is to evaluate the safety of mosunetuzumab, including the dosing schedule and tolerability of doses, and the profile of dose-limiting toxicities (DLTs), based on the following endpoints: Incidence and severity of adverse events, including DLTs. Severity will be determined according to the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) v5.0, and severity of Cytokine Release Syndrome (CRS) will be determined according to the 2019 American Society for Transplantation and Cellular Therapy (ASTCT) CRS Consensus Classification Criteria. Change from baseline in vital signs of interest. -Changes from baseline in clinical laboratory test results of interest.

[0390]

[0414] 2.2 Pharmacokinetic Goals

[0415] The pharmacokinetic (PK) objective of this study is to characterize the PK profiles of fractionated and non-fractionated single doses of mosunetuzumab based on the following endpoints: Serum concentrations of mosunetuzumab at specified time points PK parameters of mosunetuzumab

[0391]

[0416] The exploratory PK objectives of this study are to evaluate the potential relationships between drug exposure, pharmacodynamics, and safety of mosunetuzumab based on the following endpoints: Relationship between serum concentrations or PK parameters of mosunetuzumab, pharmacodynamics, and safety endpoints

[0392]

[0417] 2.3 Pharmacodynamic goals

[0418] The pharmacodynamic (PD) objective of this study is to characterize the PD effect of mosunetuzumab in participants with SLE based on the following endpoints: Peripheral B cell counts at the indicated time points. Duration of B cell depletion

[0393]

[0419] 2.4 Immunogenicity goals

[0420] The immunogenicity goal of this study is to evaluate the immune response to mosunetuzumab based on the following endpoints: Prevalence of anti-drug antibodies (ADA) at baseline and incidence of ADA during the study. The goal of this exploratory immunogenicity study is to evaluate the potential impact of ADA. Based on the following endpoints: Relationship of ADA status to safety, PK, and biomarker endpoints.

[0394]

[0421] 2.5 Exploratory activation goals Patient Global Impression of Severity (PGI-S). · Physician Global Assessment (PGA). Changes from baseline titers in antinuclear antibody (ANA) and anti-double-stranded DNA (dsDNA) antibody (IgG) titers. Change from baseline in complement C3. Change from baseline in complement C4.

[0395]

[0422] 2.6 Exploratory Biomarker Goals

[0423] The exploratory biomarker goal of this study is to identify and / or evaluate biomarkers that are associated with susceptibility to developing adverse events or that may lead to improved monitoring or surveillance of adverse events (i.e., safety biomarkers), that may provide evidence of mosunetuzumab activity (i.e., PD biomarkers), or that may increase knowledge and understanding of disease biology and drug safety based on the following endpoints: - Relationships between blood, plasma, and serum biomarkers and PD, safety, PK, or other outcomes Biomarker endpoints -Biomarkers in blood, plasma, and serum and their relationship to mechanisms ·Effects of Mosunetuzumab Changes in autoantibody titers (anti-Smith antigen [Sm], anti-Sjögren's syndrome-related -antigen A [SSA], anti-Sjögren's syndrome-related antigen B [SSB], and anti-ribonucleoprotein [RNP] at designated time points after administration of mosunetuzumab -Changes in CRS-related biomarkers at specified time points after administration of mosunetuzumab Changes in T cell subsets at designated time points after mosunetuzumab administration

[0396]

[0424] 2.7 Other Exploratory Goals

[0425] An additional exploratory objective was to evaluate the efficacy of tocilizumab in treating severe cytokine release syndrome (CRS) after mosunetuzumab treatment based on the following endpoints: Outcome of CRS events and duration of events. Changes in cytokine levels, CRS-related biomarkers, and clinical laboratory values ​​following administration of tocilizumab for the treatment of CRS.

[0397] Example 3 Study Design (Desktop)

[0426] 3.1 Test Description

[0427] The study is a Phase Ib, multicenter, open-label, dose-escalation study to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of mosunetuzumab in participants with SLE. The study is expected to enroll up to 50 participants with SLE at approximately 15 investigational sites worldwide. Approximately 13-25 participants will be enrolled during the dose-finding and dose-escalation periods. Participants who withdraw for any reason other than DLT during the DLT evaluation period (see 3.1.7.2) will be replaced. During the dose expansion period, additional participants may be added to replace participants who have discontinued prematurely, to expand existing dose cohorts, to fill cohorts with modified doses, or to evaluate specific target subgroups (e.g., participants receiving specific permitted SLE background therapy). Figures 1 and 2 provide an overview of the study design.

[0398]

[0428] The study will consist of the following study periods: Screening, Dose-finding, Dose-escalation, Dose-expansion, and Safety Follow-up (SFU). Participants in the non-fractionated / dose-finding cohort will receive non-fractionated doses of mosunetuzumab on day 1, while participants in the fractionated / dose-finding cohort will receive split doses on days 1 and 8. The duration of the SFU will be a minimum of 12 months or longer, depending on participants' time to B-cell replacement.

[0399]

[0429] screening

[0430] Consenting participants will enter a screening period of up to 28 days to be assessed for eligibility.

[0400]

[0431] Patients who do not meet the criteria for inclusion in this study (screening failures) may be eligible for three opportunities to rescreen (for a total of four screens per patient). The investigator will document the reason for ineligibility in the screening record.

[0401]

[0432] 3.1.2 Dosage setting

[0433] The study's non-split / dose-finding cohort will consist of one participant assigned to receive a single dose of 1.6 mg mosunetuzumab followed by one participant receiving a single dose of 5 mg mosunetuzumab. The 5 mg cohort will be conducted using a 3+3 design with at least three and up to six participants total. If the first two participants in the 5 mg cohort experience DLTs, only two participants will be enrolled in the 5 mg cohort.

[0402]

[0434] To assess for severe, unexpected acute drug or injection-related toxicity, participant dosing will be staggered by at least 72 hours and all participants will be hospitalized for 72 hours.

[0403]

[0435] The step dose used as the Day 1 dose during the dose escalation period will be informed by the totality of clinical data obtained during the dose finding period.

[0404]

[0436] 3.1.3 Dose escalation

[0437] For dose escalation, split dosing is planned on days 1 and 8. Participants will receive a step dose (determined by the titration period) on day 1, followed by a 15 mg, 45 mg, or 60 mg dose on day 8 in each split / escalation cohort. Dose escalation will be performed for each split cohort using a 3+3 design with at least three and up to a total of six participants. In each split cohort, each participant's day 1 dose must be separated by at least 72 hours from the previous participant's day 1 dose.

[0405]

[0438] In this study, there will be an interval of at least 7 days between the last participant in the non-fractionated dose-finding cohort and the first participant in the first fractionated dose-escalation cohort to allow for completion of the DLT evaluation period in the non-fractionated dose-finding cohort and review of the data by the Internal Monitoring Committee (IMC). Similarly, subsequent dose-escalation cohorts will have an interval of at least 7 days from the last dose of the last patient in the preceding cohort to allow for completion of the DLT evaluation period and review of the data by the IMC.

[0406]

[0439] Similar to the non-fractionated titration cohort, participant dosing will be staggered by at least 72 hours, and all participants will be hospitalized for 72 hours after dosing on Days 1 and 8. As more safety, PK, and PD information becomes available from participants receiving split doses through dose escalation, hospitalization requirements will be reevaluated periodically by the IMC.

[0407]

[0440] After completion of the DLT evaluation period (7-14 days), all participants will be closely monitored for adverse events during the study and SFU. Adverse events will be graded according to the NCI CTCAE v5.0 and CRS will be graded according to the ASTCT 2019 CRS Consensus Grading Criteria.

[0408]

[0441] The IMC reviews safety data and makes recommendations regarding dose escalation and overall study conduct to ensure the safety of participants while receiving study treatment.

[0409]

[0442] 3.1.3.1 Dose Titration Rules

[0443] All dose escalation decisions are made based on the recommendation of the IMC. Safety information, including relevant adverse events and laboratory data, is reviewed prior to each dose escalation decision. Dose escalation may be stopped or modified if deemed appropriate by the sponsor based on review of real-time clinical data.

[0410]

[0444] During the dose escalation period, the decision to proceed to the next higher dose will be made according to the following rules based on a 3+3 dose escalation design: A minimum of three participants will be enrolled in the cohort unless the first two participants experience a DLT, in which case enrollment in the cohort will close. If none of the first 3 DLT-evaluable participants develop a DLT, then upon completion of the DLT evaluation period and confirmation of IMC, enrollment of the next dose escalation cohort may proceed. If 1 of the first 3 DLT-evaluable participants experiences a DLT, the cohort will be expanded to at least 6 participants. All participants will be evaluated for DLT before deciding on dose escalation. o If a DLT is observed in 17% of participants in a cohort (e.g., 1 of 6 DLT-evaluable participants experience a DLT), enrollment in the next dose escalation cohort may proceed. If a DLT is observed in 17% of participants in a cohort, further enrollment and dose escalation will be discontinued at that dose level.

[0411]

[0445] Available PK and PD data (e.g., evidence of a dose-dependent increase in plasma IL-6 levels following administration of mosunetuzumab) may also be considered by the IMC as supportive data to aid in the interpretation of the clinical data, when relevant.

[0412]

[0446] 3.1.4 Dose expansion

[0447] The dose expansion period is designed to obtain additional information on safety, tolerability, PK, and PD for doses up to and including the highest dose level approved by the IMC. In addition to the planned 13-25 participants in the dose-finding and dose-escalation cohorts, additional participants may be enrolled in existing cohorts at the sponsor's discretion, based on the recommendation of the IMC. Alternatively, additional participants may be enrolled to obtain more information on specific participant subpopulations or to evaluate additional dose cohorts evaluating intermediate dose levels between the two dose levels.

[0413]

[0448] Dose expansion may begin at any time during the study, provided that the dose of mosunetuzumab administered does not exceed the maximum dose level approved by the IMC. Up to 50 participants in total may be enrolled in the study.

[0414]

[0449] Administration of the Day 1 doses to each participant in the dose expansion will be staggered by at least 24 hours. Hospitalization requirements during dose expansion will be based on available safety, PK, and PD data, and the recommendation of the IMC. Dose staggering and hospitalization requirements may be further modified based on the recommendation of the IMC. The sponsor must receive confirmation of the status of the previous participant before the next participant receives study drug.

[0415]

[0450] 3.1.5 Safety Follow-up

[0451] All participants who receive any dose of mosunetuzumab will be followed for safety for at least 12 months after receiving mosunetuzumab.

[0416]

[0452] If a participant's B-cell count recovers to pre-treatment nadir or lower limit of normal (LLN), whichever is lower, by the 12-month SFU visit, no further SFU is required.

[0417]

[0453] If the participant's B-cell count has not recovered to pre-treatment nadir or LLN, whichever is lower, by the 12-month SFU visit and the participant has not received subsequent therapy associated with peripheral B-cell depletion (including, but not limited to, rituximab, cyclophosphamide, obinutuzumab, ofatumumab, or belimumab), SFU will continue every 6 months until one of the following occurs: ·Peripheral differentiation antigen group 19 + (CD19 + ) B cells return to pre-treatment nadir or to LLN, whichever is lower. -Receiving treatment associated with peripheral B cell depletion. -Exam completed.

[0418]

[0454] If treatment associated with peripheral B-cell depletion is planned during SFU beyond the 12th month, a final SFU visit should be performed before receiving this treatment.

[0419]

[0455] 3.1.6 Internal Monitoring Committee

[0456] The IMC will be used during the study to make recommendations regarding the conduct of the study based on study safety data, PK and PD information to ensure the safety of participants.

[0420]

[0457] The IMC will consist of an IMC Medical Monitor Chair, external to the project, and representatives from clinical science, safety science, and biostatistics. The IMC may request the participation of additional sponsor representatives (e.g., clinical pharmacology or biomarker scientists) in data analysis and / or dose escalation or modification decisions.

[0421]

[0458] The IMC will review all cumulative data, including but not limited to the incidence and nature of adverse events, serious adverse events, deaths, grade 3 adverse events, and adverse events of special interest. The IMC will make decisions regarding dose escalation and make recommendations regarding enrollment into expansion cohorts.

[0422]

[0459] The IMC may make further recommendations regarding the conduct of the study, including, but not limited to, conducting additional safety analyses, changing hospitalization and premedication requirements, amending the study protocol, holding participant enrollment pending further safety evaluations, enrolling additional participants at a particular dose level and schedule to obtain additional safety data, withholding or discontinuing study drug, or terminating the study.

[0423]

[0460] The IMC will be convened after all patients in the dose-finding cohort have completed the DLT evaluation period and prior to dose escalation of any mosunetuzumab dose cohort ≥ 5 mg.

[0424]

[0461] The IMC may also be convened on an ad-hoc basis and at the request of the Medical Monitor.

[0425]

[0462] 3.1.7 Dose-limiting toxicity

[0463] 3.1.7.1 Definition of Dose-Limiting Toxicity Any of the following adverse events occurring during the DLT evaluation period (defined in 3.1.7.2) will be defined as a DLT: Grade ≥3 CRS (per ASTCT CRS grading criteria) with the following exceptions: o Treatment-responsive grade 3 CRS (i.e., clinical improvement within 8-12 hours of tocilizumab / corticosteroid administration) with symptomatic improvement to grade ≤1 for 3 consecutive days. Drug-related grade ≥ 3 hematological adverse events in the absence of any other clearly identifiable cause, with the following exceptions: Non-febrile grade 3 or 4 neutropenia (i.e., ANC < 1.0 × 10 9 / L without: o A single temperature of ≥38.3°C or a temperature of ≥38.0°C [100.4°F] lasting ≥1 hour) with no delay to next dose >3 days, and / or grade ≤2 (i.e., ANC ≥1.0 x 10) within the DLT evaluation period 9 / L). Grade 3 or 4 thrombocytopenia (i.e., platelet count <50 × 10 9 / L) to improve grade o1 or good (i.e., platelet count ≥ 75 × 10 9 / L) without a delay of more than 3 days to the next dose and / or without platelet transfusion within the DLT evaluation period and without any bleeding events deemed clinically significant by the investigator. Grade 3 or 4 anemia (i.e., hemoglobin < 8.0 g / dL) with improvement to Grade ≤ 2 (i.e., hemoglobin ≥ 8.0 g / dL) within the DLT evaluation period with no delay of more than 3 days to the next dose and / or no need for urgent transfusion. o Lymphopenia and / or leukopenia due to depletion of B cells, monocytes, T cells, and natural killer (NK) cells are not considered DLTs as these are expected PD outcomes of SC mosunetuzumab treatment. Drug-related grade ≥3 non-hematologic adverse events that the investigator did not consider to be attributable to other clearly identifiable causes, with the following exceptions: CRS occurring in association with grade ≤2 CRS (per ASTCT CRS Consensus Grading Criteria) and lasting ≥3 days 1 Signs and symptoms in patients with grade 3 (according to NCI CTCAE v5.0). Patients with Grade 3 laboratory values ​​with elevated AST or ALT and / or total bilirubin 2 (per NCI CTCAE v5.0) and associated with Grade ≤2 CRS (per ASTCT CRS Grading Criteria) with no delay of the next dose >3 days and / or Grade 1 or better within the DLT evaluation period 3 Something that improves. o Grade 3 laboratory abnormalities that are asymptomatic and deemed by the investigator to be clinically insignificant or not relevant. Hy's Law: An event with early evidence of cholestasis (elevated serum ALP) or an elevation of AST or ALT >3x the upper limit of normal (ULN) in combination with either an elevation of total bilirubin >2x the ULN or clinical jaundice in the absence of other causes such as pre-existing or acute liver disease, concomitant exposure to known hepatotoxic agents, documented infectious etiology (e.g., HIV, Hepatitis B virus [HBV], and Hepatitis C virus [HCV]) or CRS. Hy's law indicates possible drug-induced liver injury and is considered a DLT (see 5.3.5.11).

[0426]

[0464] Signs and symptoms of SLE, progression of SLE, and recognized complications of the disease are not considered DLTs.

[0427]

[0465] 3.1.7.2 Evaluation Period for Dose-Limiting Toxicity

[0466] For non-split doses (administered as a single dose on Day 1), the DLT evaluation period is defined as Days 1 through 7. In the event of toxicity, recovery will be evaluated within 3 days after the end of the DLT period for the purpose of DLT determination.

[0428]

[0467] For non-split doses (administered on days 1 and 8), the DLT evaluation period is defined as days 1 through 14. If the scheduled day 8 dose is delayed by 3 days or less, the end of the DLT evaluation period will be extended by the respective number of days (up to 3 days) from the day the day 8 dose was administered.

[0429]

[0468] 3.1.7.3 Definition of Dose-Limiting Toxicity – Evaluable

[0469] The determination of whether a participant is assessable for DLT assessment will be made according to the following rules: Participants who receive mosunetuzumab and remain in the study through the DLT evaluation period are considered DLT-evaluable. Participants who experience a DLT during the DLT evaluation period are considered DLT-evaluable. Participants who discontinue study treatment or the study for reasons other than DLT before the end of the DLT evaluation period will be considered inevaluable for DLT assessment and will be replaced with an additional participant. Participants whose scheduled day 8 dose is delayed by more than 3 days due to events other than DLT will discontinue study treatment. These participants will be considered non-DLT evaluable and may be replaced at the discretion of the Medical Monitor.

[0430]

[0470] 3.2 Completion and duration of the study

[0471] The end of the study is defined as the date the Last Participant, Last Visit (LPLV) occurs. LPLV occurs when the last participant completes SFU requirements as outlined in 3.1.4 for up to 18 months after receiving mosunetuzumab. In addition, the sponsor may discontinue the study at any time. The total study duration, from screening of the first participant to study completion, is expected to be approximately 41 months.

[0431] Example 4 Materials and Methods (Desktop)

[0472] 4.1 Participants

[0473] Approximately 13-25 patients with active SLE receiving standard non-biologic treatment for SLE will be enrolled in the dose-finding and dose-escalation periods of the study. Additional participants may be enrolled in the dose-expansion period, at the sponsor's discretion, based on the recommendation of the IMC. Up to 50 participants in total may be enrolled in the study.

[0432]

[0474] 4.1.1 Inclusion Benchmark

[0475] Participants must meet the following criteria for study inclusion: Signed informed consent. -Be between 18 and 75 years of age at the time of signing the informed consent. ·Ability to adhere to clinical trial protocols. - Have been diagnosed with SLE according to the 2019 EULAR / ACR classification criteria (see Figure 6) at least 12 weeks prior to screening. Demonstrated positive ANA (1:160) or anti-dsDNA and / or anti-Sm antibodies above the ULN within the past 12 months or during screening. Active SLE disease at screening by clinical assessment. Currently receiving stable doses of one or more of the following classes of standard therapies for the treatment of SLE: OCS, antimalarials, conventional immunosuppressants. For participants receiving oOCS, treatment with ≤40 mg / day prednisone or equivalent (see Table 4) at a stable dose for at least 7 days prior to Day 1 during Screening. For participants taking antimalarial medication, the medication was on a stable dose ≥ 4 weeks prior to and during screening. o For participants receiving immunosuppressants, treatment with a single immunosuppressant at a stable dose for at least 4 weeks prior to screening and during screening. Conventional immunosuppressants include azathioprine, MMF, mycophenolate, and methotrexate (oral, SC, or intramuscular injection). For women of childbearing potential: Agree to remain abstinent (abstain from heterosexual intercourse) or use a method of contraception defined below: Women must remain abstinent or use a method of contraception with an annualized failure rate of less than 1% during treatment and for 3 months after the last dose of mosunetuzumab and for 3 months after the last dose of tocilizumab. o Women are considered to be of fertility if they are postmenopausal, have not reached the postmenopausal state (amenorrhea for 12 or more consecutive months with no identified cause other than menopause), and are not permanently infertile due to surgery (i.e., removal of the ovaries, fallopian tubes, and / or uterus) or other causes as determined by the investigator (e.g., Müllerian duct aplasia). The definition of fertility may be adapted to local guidelines or regulations. o Examples of contraceptive methods with failure rates of less than 1% per year include bilateral tubal ligation, male sterilization, hormonal contraceptives that suppress ovulation, hormone-releasing intrauterine devices, and copper intrauterine devices. o The reliability of sexual abstinence should be assessed in relation to the duration of the clinical trial and the participants' preferred usual lifestyle. Periodic abstinence (e.g., calendar, ovulation, symptom-thermal, or postovulatory methods) and withdrawal are not adequate contraceptive methods. Where required by local guidelines or regulations, locally accepted appropriate contraceptive methods and information on the reliability of abstinence should be included in the local informed consent form. TIFF2024543509000005.tif74170

[0433]

[0476] 4.1.2 Exclusion criteria

[0477] Participants will be excluded from the study if they meet any of the following criteria: - Pregnant or breastfeeding, or planning to become pregnant during the study or within 3 months after the last dose of mosunetuzumab or within 3 months after the last dose of tocilizumab. Women of childbearing potential must have a negative serum pregnancy test result at screening before starting study drug treatment. Active severe or unstable lupus-related neuropsychiatric disease that may require treatment with a therapy prohibited by the protocol (see 4.4.3). Examples of neuropsychiatric SLE manifestations include, but are not limited to, meningitis, retinitis, cerebral vasculitis, myelopathy, demyelinating syndromes, acute confusional state, psychosis, acute stroke or stroke syndromes, cranial neuropathy, status epilepticus or seizures, cerebellar ataxia, and multiple mononeuritis. · Active overlap syndrome with mixed connective tissue disease or systemic sclerosis within 1 year from Day 1. Fulminant or severe antiphospholipid syndrome within 1 year of Day 1. Antiphospholipid syndrome well controlled with anticoagulant therapy for at least 3 months prior to Day 1 is permitted. ·The presence of significant lupus-related renal disease and / or renal impairment that may require treatment with therapies prohibited by the protocol. Peripheral CD19+ B-cell count <25 cells / μL. -Having received treatment with the investigational drug within 30 days or within 5 drug elimination half-lives (whichever is longer) prior to starting study treatment and during the study. oSARS-CoV-2 vaccines have been approved in the United States through the Emergency Use Authorization process; all other processes in other regions are not considered investigational products for purposes of this exemption. -Having received any of the following exclusionary therapies: o Anti-CD19 or anti-CD20 therapy, such as blinatumomab, obinutuzumab, rituximab, ocrelizumab, or ofatumumab, less than 12 months prior to or during screening. o JAK, Bruton's tyrosine kinase, or tyrosine kinase 2 inhibitors, or investigational drugs, including baricitinib, tofacitinib, upadacitinib, filgotinib, ibrutinib, or fenebrutinib, within 30 days prior to or during Screening. o Tacrolimus, cyclosporine, or voclosporine within 30 days prior to or during screening. o Cyclophosphamide or biologic therapy, including but not limited to belimumab, ustekinumab, anifrolumab, secukinumab, or atacicept, in the 2 months prior to or during screening. o Live or attenuated vaccines within 28 days prior to screening or during screening. SARS-CoV-2 vaccines are permitted as long as they are neither live nor attenuated. Conditions at high risk for clinically significant bleeding or requiring plasmapheresis, IV immune globulin, or acute blood product transfusion. ·Serious or uncontrolled medical illness that would prevent the Participant from participating. · HIV infection (defined as a positive HIV-1 and / or HIV-2 antibody test). Acute or chronic HBV (defined as a positive serologic test for hepatitis B surface antigen [HBsAg] [US Centers for Disease Control and Prevention 2021]). Participants with negative oHBsAg and hepatitis B surface antibody (HBsAb) tests and positive total hepatitis B core antibody (HBcAb) tests were ineligible. Acute or chronic HCV (defined as a positive hepatitis C virus antibody test). ·Tuberculosis (TB) infection. Testing for oTB is performed at the time of screening; the choice of test (skin or blood test) will be made according to local clinical practice. o Latent TB after completion of appropriate treatment is not an exclusion. Known or suspected chronic active Epstein-Barr virus (EBV) infection or cytomegalovirus (CMV) infection. · Active infection of any kind, except fungal infections of the nail bed. A significant infectious episode meeting any of the following criteria: o Requires hospitalization for 8 weeks prior to or during screening. o Requires IV treatment with antibiotics (or anti-infectives) for 8 weeks prior to screening or during screening. o Treatment with oral antibiotics (or anti-infectives) is required for 2 weeks prior to or during screening. Antibiotics or anti-infectives in the absence of significant infectious episodes are not an exclusion. History of serious recurrent or chronic infections. History of progressive multifocal leukoencephalopathy (PML). History of cancer within the past 5 years, including solid cancer, hematologic cancer, and carcinoma in situ. o Participants are eligible if they have treated or excised and cured non-melanoma skin cancer. Major surgery requiring hospitalization within 4 weeks prior to or during screening, or scheduled surgery or procedure requiring hospitalization within 12 weeks after study drug administration. · Current alcohol or drug abuse, or a history of alcohol or drug abuse within 12 months prior to screening or at the time of screening. ·Intolerance or contraindication to the study therapy, including a history of severe allergic or anaphylactic reactions to monoclonal antibodies or known hypersensitivity to any component of mosunetuzumab injection. Any of the following laboratory parameters: oAST or ALT >2.5 × ULN. Total bilirubin >1.5 x ULN. Participants with a documented history of Gilbert's syndrome and elevated total bilirubin accompanied by elevated indirect bilirubin were eligible. oANC<1.5×109 / L(<1500 / mm 3 ) o Platelet count <100×10 9 / L(100,000 / mm 3 ) Hemoglobin < 100 g / L Estimated glomerular filtration rate (eGFR) < 30 ml / min / 1.73 m 2 (Calculated according to the Chronic Kidney Disease Epidemiology Collaboration Equation (Levey et al. 2009 )). o Positive serum human chorionic gonadotropin at screening.

[0434]

[0478] 4.2 Method of treatment allocation

[0479] 4.2.1 Treatment allocation

[0480] This is an open-label study. After initial written informed consent is obtained and all screening procedures and assessments are completed, and participant eligibility is established, the study site will obtain the participant's identification number and cohort allocation via an interactive voice or web-based response system (IxRS).

[0435]

[0481] The study is expected to enroll up to 50 participants with SLE at approximately 15 investigational sites worldwide. Approximately 13-25 participants will be enrolled during the dose-finding and dose-escalation periods. Participants who withdraw for any reason other than DLT during the DLT evaluation period will be replaced. During the dose expansion period, additional participants may be added to replace participants who discontinue prematurely, to expand existing dose cohorts, to fill cohorts at modified doses, or to evaluate specific subject subgroups (e.g., participants receiving specific permitted SLE background therapy).

[0436]

[0482] Target population

[0483] Included Benchmark

[0484] Participants must meet the following criteria for study inclusion:

[0485] Signed informed consent.

[0486] Age ranged from 18 to 75 years at the time of signing informed consent.

[0487] Ability to adhere to clinical trial protocols.

[0437]

[0488] 4.3 Study Treatment and Other Treatments Relevant to Study Design

[0489] The investigational medicinal product (IMP) for this study is mosunetuzumab. Tocilizumab for the treatment of CRS is also considered an IMP. Corticosteroids, immunosuppressants, antimalarials, and prior treatment with mosunetuzumab are considered non-investigational medicinal products (NIMPs).

[0438]

[0490] 4.3.1 Treatment Preparation and Packaging

[0491] 4.3.1.1 Mosunetuzumab for Subcutaneous Administration: Mosunetuzumab for SC administration will be supplied by the Sponsor as a sterile liquid in 2 mL glass vials. Please refer to the Pharmacy Manual and Mosunetuzumab Investigator Brochure for information regarding the formulation, packaging, and handling of mosunetuzumab.

[0439]

[0492] 4.3.1.2 Tocilizumab: Tocilizumab will be supplied by the sponsor as a sterile liquid in 10 mL glass vials. For information regarding the tocilizumab formulation, refer to the Pharmacy Manual and Tocilizumab Investigator Brochure. Tocilizumab may be obtained locally by the investigational site for emergency use, where permitted by local regulations, and will be prepared and handled by healthcare professionals in accordance with local prescribing information. For further instructions regarding recommended storage conditions and packaging, refer to local prescribing information.

[0440]

[0493] 4.3.2 Study Treatment Dose, Administration, and Compliance: Treatment regimens are summarized in 3.1. For detailed instructions regarding drug preparation and administration of mosunetuzumab, please refer to the Pharmacy Manual.

[0441]

[0494] 4.3.2.1 A weight-independent uniform dosing regimen for mosunetuzumab will be used for mosunetuzumab. The dose of mosunetuzumab for each participant will vary by dose level assignment, as detailed in 4.2.1. Mosunetuzumab will be administered to participants by SC injection using a standard medical syringe, with the final volume of mosunetuzumab not exceeding 2.0 mL. Mosunetuzumab will be administered in an environment with ready access to trained intensive care staff and facilities equipped to respond to and manage medical emergencies. Mosunetuzumab will be administered over 30 seconds to 2 minutes by qualified staff. After each SC administration of mosunetuzumab, participants will be observed for fever, chills, rigors, hypotension, nausea, or other signs and symptoms of CRS. Vital signs should be monitored according to the assessment schedule. Recommended management of CRS is detailed in section 5.1.3.3.

[0442]

[0495] 4.3.2.2 Premedication

[0496] All participants will receive the following premedication for each mosunetuzumab injection: Corticosteroid premedication consisting of 10 mg dexamethasone should be administered orally prior to, 24 hours ± 4 hours after, and 48 hours ± 4 hours after each injection of mosunetuzumab, i.e., on days 1, 2, and 3 for the non-split cohort and on days 1, 2, 3 and 8, 9, and 10 for the split cohort. OCS administration should occur on the days that dexamethasone is administered as premedication. Additionally, administer oral acetaminophen (e.g., 500–1000 mg) and oral diphenhydramine (50–100 mg) prior to mosunetuzumab administration. Any decision to modify corticosteroid premedication requirements will be made based on the recommendation of the IMC (see 3.1.6).

[0443]

[0497] 4.3.2.3 Tocilizumab

[0498] Tocilizumab should be administered for the treatment of CRS, if necessary, as described in section 5.1.3.3. Tocilizumab may be obtained locally by the investigational site for emergency use, if permitted by local regulations, and will be prepared and handled by healthcare professionals according to practice. Refer to the local prescribing information for further instructions regarding dosage, administration, recommended storage conditions and packaging. If not permitted by local regulations, tocilizumab will be supplied by the sponsor and information regarding the formulation, handling and administration of tocilizumab will be provided in the Pharmacy Manual. Any overdose or error of tocilizumab should be documented in the Investigational Product Administration electronic case report form (eCRF). Adverse events related to overdose or error of study drug should be recorded in the Adverse Events eCRF.

[0444]

[0499] 4.4 Combination therapy

[0500] Concomitant medications consist of any medications (e.g., prescription or over-the-counter medications, vaccines, herbal or homeopathic remedies, dietary supplements) used by the patient in addition to protocol-mandated treatments from 7 days prior to the start of study medication through the final SFU / Early Discontinuation Visit. All such medications must be reported to the investigator and recorded on the Concomitant Medications eCRF.

[0445]

[0501] Authorized (full marketing authorisation or temporary) SARS-CoV2 vaccines administered during the specified period should be reported as concomitant medications.

[0446]

[0502] 4.4.1 Permitted Therapies

[0503] In general, investigators should manage participants' care with supportive care as clinically indicated, according to local practice. Participants are permitted to use the following therapies during the study: Oral contraceptives (see 4.1.1) Hormone replacement therapy Study entry requires oral prednisone at up to 40 mg / day or equivalent (see Table 4). Patients should strive to maintain a stable dose from screening through the DLT evaluation period. However, on days when dexamethasone is administered as premedication, OCS doses should be maintained. oFollowing the DLT evaluation period, the prednisone dose may be adjusted and tapered if clinically appropriate. Topical corticosteroids (with or without OCS) are permitted as monotherapy. ·Antimalarials (hydroxychloroquine, chloroquine, or quinacrine) and conventional immunosuppressants (i.e., azathioprine, MMF, mycophenolate, or methotrexate [oral, SC, or intramuscular routes]) (see 4.1.1). o During the screening and DLT evaluation periods, the doses of antimalarials and / or oral immunosuppressants may not be adjusted except in the event of one or more drug-related toxicities. ·Nonsteroidal anti-inflammatory drugs (NSAIDs). o Use of NSAIDs at approved doses will be permitted during the study, but initiation of new medications should be avoided, if possible, from screening through completion of the DLT evaluation period. Acetaminophen (paracetamol) Care must be taken to ensure that the total dose of acetaminophen (paracetamol), including the amount administered as a premedication, does not exceed the approved daily dosage range. ·Treatment of CRS according to published recommendations and / or institutional practice. · Calcium and / or Vitamin D supplementation. Anticoagulant or antiplatelet therapy for control of thrombosis risk if started at least 2 months prior to screening. Antihypertensive therapy. Antihypertensive therapy, including angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, is permitted, but initiation of new medications should be avoided if possible from screening until completion of the DLT evaluation period. · Hydroxymethylglutaryl-CoA (HMG-CoA) reductase inhibitors ("statins") and bisphosphonates. o HMG-CoA reductase inhibitors and bisphosphonates are permitted but may not be initiated until the DLT evaluation period is complete. If participants enter the study taking such medications, every effort should be made to keep the dose stable to avoid confounding the study results. Hematopoietic growth factor and blood component transfusions. o Do not initiate transfusions of hematopoietic growth factors and blood components during screening. After study drug initiation, treatment of neutropenia, thrombocytopenia, and anemia should follow published guidelines and / or institutional practice. In general, investigators should manage patient care with supportive care as clinically indicated according to local practice.

[0447]

[0504] 4.4.2 Caution in therapy

[0505] 4.4.2.1 Vaccination

[0506] The efficacy and safety of vaccinations during peripheral B cell depletion have not been fully tested. It is recommended that a careful evaluation of the patient's vaccination record and vaccination needs be performed before receiving mosunetuzumab. For participants who may require vaccinations in the foreseeable future, such as participants planning to travel to countries requiring specific vaccinations or participants who require vaccinations / boosters for professional activities, the required vaccinations / boosters should be given at least 28 days prior to study drug administration. It is recommended that the patient's vaccination status or needs be reviewed prior to study drug administration: tetanus; diphtheria; influenza; pneumococcal polysaccharide; varicella; measles, mumps, and rubella; hepatitis B vaccine; and SARS-CoV-2 vaccine (if available locally, see section 1.3). The safety and efficacy of vaccinations with live or live attenuated vaccines in B cell depleted participants is unknown. For this reason, use of live or attenuated vaccines (e.g., measles, mumps, rubella, oral polio vaccine, Bacillus Calmette-Guerin, typhoid, yellow fever, vaccinia, or other non-licensed vaccines in this category) is specifically excluded from 28 days prior to screening until completion of SFU or B-cell recovery, whichever occurs first.

[0448]

[0507] Vaccines that do not contain live microorganisms (e.g., influenza, Pneumovax®, tetanus, and SARS-CoV-2 vaccines [see 1.3]) are not prohibited, but vaccines administered during peripheral B cell depletion may be ineffective.

[0449]

[0508] 4.4.2.2 Other treatments for systemic lupus erythematosus

[0509] Disease flares may be managed with temporary increases in corticosteroid doses while continuing on study, but efforts should be made to maintain a stable dose from screening through the DLT assessment period. If disease worsens or shows severe activity, the investigator may conclude that additional treatment for SLE is necessary, including: High-dose corticosteroids (IV methylprednisolone ≥ 250 mg or equivalent, or oral prednisone > 40 mg / day or equivalent (for ≥ 4 weeks, see Table 4). Cyclophosphamide. Any B cell depleting therapy, including but not limited to rituximab, ocrelizumab, ofatumumab, and obinutuzumab. ·Calcineurin inhibitors, including cyclosporine, tacrolimus, and bocolosporine. Other biologic or targeted therapies used to treat SLE. The safety of mosunetuzumab in combination with these therapies is unknown, so participants receiving such treatments will not receive additional injections of mosunetuzumab.

[0450]

[0510] 4.4.2.3 Drugs Administered with Caution Due to Cytochrome P450 Enzyme-Related Effects

[0511] Considering the expected pharmacological actions of mosunetuzumab, the transient release of cytokines may inhibit cytochrome P450 (CYP450) enzymes and lead to drug-drug interactions. Preliminary clinical data indicate that SC administration of mosunetuzumab induces a transient increase in plasma IL-6 levels, with peak levels occurring in the majority of patients within 1–3 days of cycle 1 dosing day 1, returning to baseline by 3–4 days. Participants at highest risk for drug-drug interactions are those taking concomitant medications that are both CYP450 substrates and have narrow therapeutic indices (see Table 5). Such concomitant medications should be monitored for toxicity and doses adjusted accordingly (see Table 5). TIFF2024543509000006.tif209170

[0451]

[0512] Hepatic CYP450 enzymes are downregulated by infection and inflammatory stimuli, including cytokines such as IL-6. Inhibition of IL-6 signaling in participants treated with tocilizumab may restore CYP450 activity to higher levels than in participants not treated with tocilizumab, leading to increased metabolism of drugs that are CYP450 substrates. In vitro studies have shown that tocilizumab has the potential to affect the expression of multiple CYP enzymes, including CYP1A2, CY2B6, CYP2C9, CYP2C19, CYP2D6, and CYP3A4. The effect of tocilizumab on CYP2C8 or transporters is unknown. In vivo studies with omeprazole (metabolized by CYP2C19 and CYP3A4) and simvastatin (metabolized by CYP3A4) reduced exposure by up to 28% and 57%, respectively, 1 week after a single dose of tocilizumab.

[0452]

[0513] The effects of tocilizumab on CYP enzymes may be clinically relevant in CYP450 substrates with narrow therapeutic indices (see Table 5), in which case the dose is adjusted individually:

[0514] Upon initiation or discontinuation of tocilizumab in participants treated with these types of medicines, therapeutic monitoring of effect (e.g., warfarin) or drug concentrations (e.g., cyclosporine or theophylline) should be performed and the patient's dose of the medicine adjusted as needed.

[0453]

[0515] Prescribers should use caution when coadministering tocilizumab with CYP3A4 substrate drugs (e.g., oral contraceptives, lovastatin, atorvastatin) where a decrease in efficacy is undesirable. The effects of tocilizumab on CYP450 enzyme activity may persist for several weeks after treatment is discontinued.

[0454]

[0516] 4.4.3 Prohibited Therapies: The following concomitant therapies are prohibited:

[0517] Treatment with any investigational drug (other than protocol-mandated investigational treatment) within 30 days or within 5 drug elimination half-lives (whichever is longer) prior to initiating study treatment and during the study.

[0455]

[0518] herbal therapy from screening through the DLT evaluation period, as the pharmacokinetics, safety profile, and potential drug-drug interactions are largely unknown.

[0456] 4.4.4 Additional Restrictions

[0519] Participants should refrain from:

[0520] Use of illicit drugs or hallucinogenic substances from screening through completion of the study, except for appropriate use of prescribed medications as determined by the investigator.

[0457]

[0521] 4.5 Test evaluation

[0522] The schedule of activities to be performed during the study is described in Figures 5A-5C (Figure 5; non-split cohort) and 6A-6C (Figure 6; split cohort). All activities must be performed and documented for each participant. Participants will be closely monitored for safety and tolerability throughout the study. Participants will be required to undergo toxicity evaluations prior to each dose. Dosing will occur only if clinical evaluations and laboratory values ​​are acceptable.

[0458] Experiment 5: Safety evaluation (desktop)

[0523] 5.1 Safety Plan

[0524] This is the first study to administer the SC formulation of mosunetuzumab to participants with autoimmune diseases, specifically SLE. Therefore, the actual risk in this participant population is unknown. Mosunetuzumab is not currently approved and clinical development of IV and SC formulations of mosunetuzumab in hematology-oncology indications is ongoing. The safety plan for participants in this study is based on clinical experience with mosunetuzumab in ongoing hematology-oncology studies. Important safety risks anticipated for mosunetuzumab are outlined below. Eligibility criteria are designed to exclude participants at high risk of toxicity (see 4.1.2). Enrollment will be staggered such that all participants in the titration and dose escalation cohorts receive a dose on Day 1 72 hours apart (see 3.1 for details). Enrollment of participants during subsequent expansion periods will be staggered by at least 24 hours, which may be further modified by IMC recommendations (see 3.1.4). Hospitalization is required for all participants in the titration cohort. Hospitalization requirements for participants in dose escalation cohorts and during the expansion period will be defined based on emerging PK and safety data and recommendations from the IMC.

[0459]

[0525] An IMC will be in place to ensure the safety of participants during the study (see 3.1.6). Premedication will be used to reduce the frequency and severity of CRS (see 4.3.2.2). Mosunetuzumab will be administered in a clinical setting with ready access to a critical care unit and staff trained to monitor and respond to medical emergencies. Participants will undergo safety monitoring throughout the study, including assessment of the nature, frequency, and severity of adverse events. Additionally, guidelines for managing adverse events, including criteria for interrupting or discontinuing treatment, are provided below.

[0460]

[0526] 5.1.1 Risks Associated with Subcutaneous Mosunetuzumab

[0527] 5.1.1.1 Cytokine Release Syndrome: The mechanism of action of mosunetuzumab is activation of immune cells against CD20 expressing cells. Thus, a spectrum of events may occur including IRR, target mediated cytokine release, and / or hypersensitivity with or without emergent ADA. Other CD20 directed and immunomodulatory therapies are associated with IRR, CRS, and / or hypersensitivity (Rituxan USPI; Gadiva USPI; Blincyto USPI).

[0461]

[0528] CRS has been reported after administration of mosunetuzumab in hematology-oncology clinical trials.

[0462]

[0529] To date, CRS events observed with mosunetuzumab in hematology-oncology clinical trials have mostly been mild to moderate in severity, included symptoms such as fever, headache, and myalgia, and responded to symptomatic treatment with analgesics, antipyretics, and antihistamines as indicated.

[0463]

[0530] Severe or life-threatening symptoms of CRS, such as hypotension, tachycardia, dyspnea, or chest discomfort, should be treated aggressively with supportive and resuscitative care as indicated, including the use of tocilizumab and / or high-dose corticosteroids, IV fluids, and other supportive care, according to institutional practice. Severe CRS may be accompanied by other clinical sequelae, such as disseminated intravascular coagulation, capillary leak syndrome, or may manifest as HLH (see 5.1.1.3). No standard of care has been established for severe or life-threatening CRS resulting from immune-based monoclonal antibody therapy. Case reports and recommendations regarding CD19 CAR-T cell therapy have been published (Teachey et al. 2013; Lee et al. 2014, Maude et al. 2014; Neelapu et al. 2018; Yescarta® USPI; Kymriah USPI; Tecartus® USPI).

[0464]

[0531] To minimize the risk and sequelae of CRS, corticosteroid premedication is indicated as described in 4.3.2.2.

[0465]

[0532] For CRS adverse event reporting procedures, see 5.3.5.1.

[0466]

[0533] See Table 1 for CRS grading according to the ASTCT consensus grading criteria (Lee, 2019).

[0467]

[0534] Guidelines for the management of participants who develop CRS are provided in 5.1.3.3, Table 6.

[0468]

[0535] Guidelines for the management of anaphylaxis:

[0536] These guidelines are intended as a reference and are not intended to replace appropriate local or facility standard operating procedures.

[0469]

[0537] Clinical criteria for diagnosing anaphylaxis Anaphylaxis is likely when any of the following three criteria are met (Sampson et al. 2006): Onset of an acute illness (lasting minutes to hours) affecting the skin, mucosal tissue, or both (e.g., hives, itching or flushing all over the body, swelling of the lips, tongue, or palate) and at least one of the following: o Respiratory problems (e.g., dyspnea, wheezing-bronchospasm, wheezing, decreased peak expiratory flow [PEF], hypoxemia). o Decreased blood pressure (BP) or associated symptoms of peripheral organ dysfunction (e.g., hypotonia [collapse], syncope, incontinence) Two or more of the following that occur rapidly (minutes to hours) after exposure to the person's likely allergen: o Infiltration of mucocutaneous tissues (e.g., generalized hives, itching-flushing, swelling of the lips, tongue, or palate). o Respiratory problems (e.g., dyspnea, wheezing-bronchospasm, wheezing, decreased PEF, hypoxemia). o Decreased BP or associated symptoms (e.g., hypotonia [collapse], syncope, incontinence). Persistent gastrointestinal symptoms (e.g. crampy abdominal pain, vomiting) Decrease in BP (minutes to hours) after exposure to a known allergen for the patient: o Adults: Systolic blood pressure less than or equal to 90mmHg or a decrease of 30% or more from the individual's baseline. Necessary equipment and medications If an anaphylactic reaction is suspected during administration of a study drug in a clinical setting, the following equipment and agents are required: Monitoring devices: ECG monitors, blood pressure monitors, oxygen saturation monitors, and thermometers ·oxygen Administer epinephrine intramuscularly (preferred route), subcutaneously, intravenously, or intratracheally according to institutional guidelines. Antihistamines Corticosteroids Intravenous fluids, tubes, catheters, and tapes Procedure: If an anaphylactic reaction is suspected during administration of an investigational product, the following procedure should be performed: 1. If possible, discontinue administration of the study drug. 2. Request additional medical assistance. 3. Ensure an adequate airway. 4. Ensure adequate surveillance is occurring with continuous electrocardiogram and pulse oximetry monitoring, if possible. 5. Administer antihistamines, epinephrine, or other medications and IV fluids as appropriate for the patient's condition and as directed by the treating physician. 6. Continue to observe the patient and record observations. (Sampson HA, Munoz-Furlong A, Campbell R, et al.Second symposium on the definition and management of anaphylaxis:Summary report-Second National Institute of Allergy and Infectious Disease / Food Allergy and Anaphylaxis Network symposium,J Allergy Clin Immunol.2006;117:391-397).

[0470]

[0538] 5.1.1.2 Neutropenia

[0539] Neutropenia is common in SLE and generally correlates with disease activity. Neutropenia is a known class effect associated with other CD20-directed therapeutics, as well as blinatumomab (Blincyto USPI). Reversible neutropenia was observed after mosunetuzumab treatment in the hematology-oncology study GO29781. Some participants who developed neutropenia received growth factor support and / or temporarily discontinued treatment. For more information, see the mosunetuzumab investigator's brochure. Guidelines for the management of participants who developed neutropenia are provided in 5.1.3.3, Table 7.

[0471]

[0540] 5.1.1.3 Adult-onset secondary or reactive macrophage activation syndrome (MAS) or hemophagocytic lymphohistiocytosis CRS with features of HLH have been reported with anti-CD19 therapy, blinatumomab, and adoptive CAR-T cell therapy (Blincyto USPI; Teachey et al. 2013; Lee et al. 2014). A fatal case of secondary HLH has been reported in the mosunetuzumab hematology-oncology trial GO29781 in a participant with NHL and chronic active EBV infection (EBV positive by EBV-encoded small RNA in situ hybridization) (see the mosunetuzumab investigator's brochure for more information). Although severe CRS and secondary HLH show overlapping pathology and symptoms, secondary HLH can be triggered by other diseases, such as infections and malignancies, as well as autoimmune diseases (Dhote et al. 2003, Ramos-Casals et al. 2014). Among autoimmune diseases, SLE is the most commonly reported, especially in the setting of disease relapse (Fukaya et al. 2008, Kim et al. 2012). Distinguishing CRS from HLH and identifying the triggers can be difficult. Although active infection with EBV is one of the most common infectious causes of HLH (Hashemi-Sadraei et al. 2015; Schram and Berliner 2015), reactivation of latent EBV can occur in patients with SLE (Jog and James 2021), which in turn can lead to HLH (Lim et al.). CMV has also been associated with the development of secondary HLH. Participants with known or suspected chronic active EBV infection or CMV will be excluded from the study due to their risk of secondary HLH (see 4.1.2). It remains to be seen whether mosunetuzumab treatment further increases the risk of developing HLH in participants with additional risk factors. There are no universally accepted criteria for diagnosing secondary or reactive HLH in the adult population, although proposed criteria have been published (Henter et al. 2007; Fardet et al. 2014; Hejblum et al. 2014).Participants suspected of having HLH should be diagnosed according to published HLH diagnostic criteria (Jordan et al.). Participants should be classified as having HLH if they meet five of the following eight criteria: Fever ≧38.5℃ ·Splenomegaly Peripheral blood cytopenia consisting of at least two of the following: Hemoglobin < 90 g / L (9 g / dL) o Platelet count <100×10 9 / L(100,000 / μL) oANC<1.0×10 9 / L(1000 / μL) Fasting hypertriglyceridemia >2.992 mmol / L (265 mg / dL) and / or hypofibrinogenemia <1.5 g / L (150 mg / dL) Hemophagocytosis in the bone marrow, spleen, lymph nodes, or liver o Low or absent NK cell activity Ferritin >500mg / L (500ng / mL) o Soluble IL-2 receptor (soluble CD25) elevated by ≥2 standard deviations above age-adjusted laboratory-specific baseline values.

[0472]

[0541] In all suspected cases of HLH, the medical monitor should be contacted immediately. Guidelines for the management of participants who develop HLH are provided in 5.1.3.3, Table 8.

[0473]

[0542] 5.1.1.4 Injection site reactions

[0543] Local injection site reactions following SC administration of the anti-CD20 monoclonal antibody rituximab have been observed (Assouline et al. 2016). Most events were mild to moderate in severity (Rituxan Hycela® USPI). Because CD4+ and CD8+ T cells (Mueller et al. 2014) and B cells (Egbuniwe et al. 2015) reside in the skin, local reactions may occur following SC administration of mosunetuzumab, and mild injection site reactions were observed in participants treated with SC mosunetuzumab in the hematology-oncology study GO29781. See 5.3.5.2 for adverse event reporting procedures for injection site reactions.

[0474]

[0544] Guidelines for the management of participants who develop an injection site reaction are provided in 5.1.3.3, Table 9.

[0475]

[0545] 5.1.1.5 Neurological adverse events

[0546] Neurotoxicity was frequently reported in participants treated with blinatumomab and CD19 CAR-T cell therapy, with symptoms including headache, confusion, aphasia, encephalopathy, tremors, seizures, and other neurological events (Blincyto USPI; Kochenderfer et al. 2014; Maude et al. 2014). The etiology of toxicity in this setting is unclear and may not respond to cytokine-directed treatments such as tocilizumab, but typically improves with discontinuation of treatment and corticosteroids (Blincyto USPI; Viardot et al. 2010; Kochenderfer et al. 2014).

[0476]

[0547] Neurotoxicity has been reported in cynomolgus monkeys receiving mosunetuzumab (see the mosunetuzumab investigator's brochure for more information). Encephalopathy has been observed in patients with hematological malignancies in the setting of CRS and / or elevated liver function tests (LFTs) after mosunetuzumab treatment (see the mosunetuzumab investigator's brochure for more information). Based on available clinical data, neurological adverse events observed with mosunetuzumab were early onset and mild in severity. The most frequent neurological events included headache, dizziness, and insomnia (see the mosunetuzumab investigator's brochure for more information).

[0477]

[0548] Guidelines for the management of participants who experience a neurological adverse event are provided in 5.1.3.3, Table 10.

[0478]

[0549] 5.1.1.6 Infectious diseases

[0550] Because of the expected mechanism of action that results in significant B cell depletion, mosunetuzumab may be associated with an increased risk of infection. Infections have been reported in participants receiving other CD20-directed therapies as well as blinatumomab (Blincyto USPI; Gazyva USPI; Rituxan USPI). In addition, participants with SLE may be taking corticosteroids and other traditional immunosuppressants, further increasing the risk of infection. Therefore, mosunetuzumab should not be administered in the presence of active infections, and participants with a history of recurrent or chronic infections should be excluded.

[0479]

[0551] PML has been associated with treatment with CD20-directed therapies, including rituximab and obinutuzumab. The diagnosis of PML should be considered for participants presenting with new-onset neurological symptoms, and a neurologist should be consulted and diagnostic procedures, including brain magnetic resonance imaging (MRI) and lumbar puncture, should be performed as clinically indicated. However, new-onset neurological adverse events following the first dose of mosunetuzumab may more likely be due to the acute effects of mosunetuzumab (see 5.1.1.5), as rituximab-associated PML generally develops after prolonged exposure (Carson et al. 2009).

[0480]

[0552] Reactivation of Hepatitis B has been reported with other CD20-directed therapies. Participants with acute or chronic HBV infection or HCV infection are not eligible for this study (see 4.1.2).

[0481]

[0553] HIV-infected participants are excluded from study participation because signs and symptoms of HIV may confound the assessment of the safety profile of encephalopathy, tremors, seizures, and other neurological events. The etiology of toxicity in this setting is unclear and may not respond to cytokine-directed therapies such as tocilizumab, but typically improves with treatment cessation and corticosteroids (Blincyto USPI; Viardot et al. 2010; Kochenderfer et al. 2014).

[0482]

[0554] Neurotoxicity has been reported in cynomolgus monkeys treated with mosunetuzumab.

[0483]

[0555] Encephalopathy has been observed in the setting of CRS and / or elevated liver function tests (LFTs) following mosunetuzumab treatment in patients with hematological malignancies. Based on available clinical data, neurological adverse events observed with mosunetuzumab were early onset and mild in severity. The most frequent neurological events included headache, dizziness, and insomnia.

[0484]

[0556] Guidelines for the management of participants who experience a neurological adverse event are provided in 5.1.3.3, Table 10.

[0485]

[0557] 5.1.1.6 Infectious diseases

[0558] Because of the expected mechanism of action that results in significant B cell depletion, mosunetuzumab may be associated with an increased risk of infection. Infections have been reported in participants receiving other CD20-directed therapies as well as blinatumomab (Blincyto USPI; Gazyva USPI; Rituxan USPI). In addition, participants with SLE may be taking corticosteroids and other traditional immunosuppressants, further increasing the risk of infection. Therefore, mosunetuzumab should not be administered in the presence of active infections, and participants with a history of recurrent or chronic infections should be excluded.

[0486]

[0559] PML has been associated with treatment with CD20-directed therapies, including rituximab and obinutuzumab. For participants presenting with new-onset neurological symptoms, the diagnosis of PML should be considered, and a neurologist should be consulted and diagnostic procedures, including brain magnetic resonance imaging (MRI) and lumbar puncture, should be performed as clinically indicated. However, new-onset neurological adverse events following the first dose of mosunetuzumab may more likely be due to the acute effects of mosunetuzumab (see 5.1.1.5), as rituximab-associated PML generally develops after prolonged exposure (Carson et al. 2009).

[0487]

[0560] Reactivation of Hepatitis B has been reported with other CD20-directed therapies. Participants with acute or chronic HBV infection or HCV infection are not eligible for this study (see 4.1.2).

[0488]

[0561] HIV-infected participants will be excluded from study participation as signs and symptoms of HIV may confound the evaluation of the safety profile of mosunetuzumab. HIV, active EBV infection, and CMV infection are associated with the development of secondary HLH. Participants with HIV and known or suspected chronic active EBV infection or CMV will be excluded from the study due to their risk of secondary HLH (see 4.1.2).

[0489]

[0562] In the context of a COVID outbreak, screening for COVID prior to and during study participation should be considered according to local / institutional guidelines or applicable professional society (e.g., ACR, EULAR) guidelines.

[0490]

[0563] Guidelines for the management of participants who develop an infectious disease are provided in 5.1.3.3.

[0491]

[0564] 5.1.1.7 Thrombocytopenia

[0565] Thrombocytopenia is associated with other CD20-directed therapeutics, as well as blinatumomab (Blincyto USPI). In the hematology oncology study GO29781, reversible thrombocytopenia was observed after mosunetuzumab treatment. Furthermore, thrombocytopenia is associated with underlying SLE. In nonclinical studies of mosunetuzumab in cynomolgus monkeys, hematological findings included transient decreases in WBC, lymphocyte, monocyte, eosinophil, basophil, and platelet counts within the first day of exposure to mosunetuzumab, followed by recovery or rebound recovery between days 4 and 8. Guidelines for the management of participants who developed thrombocytopenia are provided in 5.1.3.3, Table 11.

[0492]

[0566] 5.1.1.8 Elevated liver enzymes

[0567] Transient grade 3 AST elevations accompanied by grade 2 CRS, grade 3 hepatic encephalopathy, and grade 4 LFT elevations have been observed following mosunetuzumab treatment in hematological-oncology clinical trials.

[0493]

[0568] In nonclinical studies with mosunetuzumab in cynomolgus monkeys, dose-dependent increases in serum total bilirubin were observed along with C-reactive protein (CRP), fibrinogen, PT, and PTT, consistent with mosunetuzumab-induced cytokine release and acute phase protein responses, but activation of the coagulation system was minimal. Potentially drug-related microscopic findings in the liver included single-cell hepatocyte degeneration or necrosis, and immune cell infiltration in the portal venous region. All findings showed evidence of reversibility.

[0494]

[0569] Participants with elevated LFTs at screening will be excluded from the study (see 4.1.2).

[0495]

[0570] Guidelines for the management of participants who develop elevated liver enzymes are provided in 5.1.3.3, Table 12.

[0496]

[0571] 5.1.1.9 Immunogenicity (anti-drug antibodies)

[0572] As with any recombinant antibody, mosunetuzumab may induce an immune response and participants may develop antibodies against the molecule. Participants will be closely monitored for potential immune reactions to mosunetuzumab that may affect the benefit / risk profile. Therefore, a risk-based strategy (Rosenberg and Worobec 2004a, 2004b, 2005, and Koren et al. 2008) will be utilized to detect and characterize ADA responses to mosunetuzumab. For the most up-to-date ADA information, please refer to the mosunetuzumab investigator's brochure.

[0497]

[0573] 5.1.2 Risks associated with tocilizumab

[0574] 5.1.3 Management of participants experiencing adverse events

[0575] 5.1.3.1 Dose Modifications: Dose modifications are not permitted.

[0498]

[0576] 5.1.3.2 Treatment interruptions

[0577] In patients experiencing adverse events, administration of mosunetuzumab may be temporarily interrupted (i.e., the injection on day 8 of the split-dose schedule can be postponed) to allow for improvement of the adverse event (see 5.1.3.3). Mosunetuzumab will only be administered if tolerated by the patient's clinical and laboratory evaluations. All considerations regarding schedule changes should be discussed with the medical monitor. The following guidelines should be followed for schedule changes: Participants who experience a grade 2 or 3 CRS event (2019 ASTCT CRS Consensus Grading Criteria; Table 1) will be allowed to defer the day 8 dose for up to 3 days to recover from toxicity: For Grade 3 CRS; provided that CRS is treatment responsive (i.e., clinical improvement within 8-12 hours of tocilizumab / corticosteroid administration) and symptoms improve to Grade 1 or better for 3 consecutive days, participants may receive the next dose. o For Grade 2 CRS; provided CRS improves to Grade 1 or better for 3 consecutive days, participants may receive the next dose. Participants who experience a Grade ≤ 3 adverse event (by NCI CTCAE v5.0) may skip the 8th dose to allow time for recovery from toxicity. up to 3 days Can be postponed: ■For grade 3 or 4 hematological abnormalities (in the absence of clinically significant symptoms), as well as for anemia and thrombocytopenia, no transfusion is required and participants may receive their next dose provided that their condition improves to grade 2 or less. For adverse events that cannot be attributed to other clear causes such as worsening of SLE, concomitant medications or pre-existing conditions, participants may receive the next dose provided the event has resolved to Grade 1 or better. For a clinically relevant decrease in a laboratory value, the abnormality must improve to the lower limit of Grade 1 or better or return to ≥80% of baseline, whichever is lower. For a clinically relevant increase in a laboratory value, the abnormality must improve to the upper limit of Grade 1 or better or return to ≥120% of baseline, whichever is higher. For the following findings occurring in the setting of grade ≤2 CRS (ASTCT CRS Consensus Grading Criteria; Table 1), participants may receive the following, provided: * Individual signs and symptoms of Grade 3 (per NCI CTCAE v5.0) CRS lasting 3 days or more. *Elevations in AST or ALT and / or total bilirubin that have improved to Grade 1 or better, with no individual laboratory values ​​greater than Grade 3.7 (per NCI CTCAE v5.0). ■Participants who experience a Grade 4 (NCI CTCAE v5.0) non-hematologic adverse event or DLT (see 3.1.7) during divided doses should discontinue further doses (see 4.6.1). If the next dose is delayed for more than 3 days due to toxicity or other reasons, study treatment will be discontinued. If study treatment is discontinued (i.e., the day 8 dose is not administered), the participant will remain in the study and continue study visits and respective evaluations according to the unsplit cohort activity schedule (see Figure 5).

[0499]

[0578] 5.1.3.3 Management guidelines for cytokine release syndrome

[0579] Premedication with corticosteroids, antihistamines, and antipyretics / analgesics is required prior to treatment with mosunetuzumab (see 4.3.1.1).

[0500]

[0580] Given the mechanism of action of mosunetuzumab, systemic infusion-related reactions and CRS may be indistinguishable, and therefore their evaluation and treatment are identical.

[0501]

[0581] Participants were premedicated with corticosteroids, which may blunt the fever response. Therefore, adverse events with fever, hypotension, or hypoxia attributable to mosunetuzumab and consistent with a diagnosis of systemic infusion-related reaction or CRS and not attributable to other causes should be recorded as CRS. CRS events with hypotension and / or hypoxia but without fever should be graded according to the management required for hypotension and / or hypoxia. These types of events correspond to a minimum of ASTCT grade 2 CRS. In the absence of fever, hypotension, or hypoxia, adverse events occurring within 24 hours of mosunetuzumab administration should be reported as separate adverse events, such as headache or chills.

[0502]

[0582] Management of grade ≥3 CRS should be discussed immediately between the investigator and medical monitor. As per Table 6, patients with extensive comorbidities should be closely monitored, even if CRS is moderate, with consideration of admission to the intensive care unit (ICU) and administration of tocilizumab. Severe SARS-CoV-2 infection is associated with CRS, including the proinflammatory cytokines IL-6, IL-10, IL-2, and IFN-γ. If a study patient develops severe CRS, the differential diagnosis should include SARS-CoV-2 and related tests performed at the investigator's discretion. If a diagnosis of COVID-19 is confirmed, it should be managed according to local or institutional guidelines.

[0503]

[0583] In atypical cases of late-onset CRS (onset >72 hours after mosunetuzumab injection) or treatment-refractory CRS, HLH workup should be initiated and all cases of suspected HLH should be discussed immediately with the medical monitor. TIFF2024543509000007.tif251170TIFF2024543509000008.tif251170TIFF2024543509000009.tif181170

[0504]

[0584] Neutropenia

[0585] All participants should be monitored for neutropenia at each visit, and participants experiencing neutropenia should undergo blood count monitoring until resolution of grade ≤2 events. See Table 7. TIFF2024543509000010.tif91170

[0505]

[0586] Hemophagocytic lymphohistiocytosis

[0587] In the setting of T-cell induction therapy, including mosunetuzumab, CRS is much more likely compared with secondary HLH, and given the overlap in symptoms, management of these participants should be primarily focused on treating CRS (see Table 6).

[0506]

[0588] Supportive management of HLH is generally similar to that of CRS. See Table 8.

[0507]

[0589] In all cases of suspected HLH, participants should be hospitalized and the following diagnostic and monitoring measures should be initiated: Frequent (e.g., every 4 hours) vital signs and physical examination (including evaluation for splenomegaly) Continuous (at least daily) monitoring of serum chemistry, CBC, LFTs, ferritin, PT / PTT, fibrinogen, D-dimer, and triglycerides Consideration of bone marrow and / or lymph node biopsy to evaluate for hemophagocytosis and active infection, including evaluation of EBV protein localization in T / B / NK cells. Complete infectious disease work-up including:- Blood cultures (bacterial and fungal) Urine culture and urinalysis o Radiological examination (e.g. chest x-ray or CT scan) Assessment for active viral infections, including but not limited to EBV and CMV Assessment of soluble CD25 and NK cell function. If not available locally, these can be tested at a central laboratory. TIFF2024543509000011.tif93170

[0508]

[0590] Injection site reactions

[0591] Participants who experience local injection site reactions following SC administration of mosunetuzumab should be managed according to the guidelines detailed in Table 9. TIFF2024543509000012.tif120170

[0509]

[0592] Neurological Adverse Events

[0593] Neurological adverse events will be closely monitored during the study. Participants should be regularly assessed for signs or symptoms of neurological adverse events as part of clinical examination during treatment. If new or worsening neurological adverse events are suspected, participants should be referred to a neurologist for further evaluation for possible drug-related neurotoxicity. If neurotoxicity is suspected, treatment with corticosteroids should be considered. Imaging studies (e.g., diffusion-weighted MRI) should be performed if clinically indicated (see Table 10). The decision to continue or withhold study treatment for grade 1 neurological adverse events is at the investigator's discretion. For grade 2 neurological adverse events, study treatment will be withheld until the event has returned to baseline, without medication for at least 3 days. For grades 3 and 4 neurological adverse events, study treatment should be permanently discontinued. For grade ≥ 3 seizures, study treatment will be permanently discontinued.

[0510]

[0594] For participants who develop a neurological adverse event that may affect driving, investigators should advise them to refrain from driving or engaging in hazardous occupations or activities until the event has resolved. Neurological adverse events that may affect cognition or consciousness and may affect driving (neurological events of cognition or consciousness that affect driving) include, but are not limited to, amnesia, aphasia, confusion, delirium, reduced level of consciousness, attention disorder, encephalopathy, hallucinations, hepatic encephalopathy, insomnia, memory impairment, seizures, visual hallucinations, and dizziness.

[0511]

[0595] Participants who develop other neurological adverse events, such as tremor or dizziness, should be evaluated by neurological examination to determine whether the adverse event may impair the participant's ability to drive or engage in hazardous occupations or activities.

[0603] For participants assessed as being at high risk, investigators should advise them to refrain from driving or engaging in hazardous occupations or activities until their condition has improved.

[0512]

[0596] Guidelines for the management of neurologic adverse events are summarized in Table 10. TIFF2024543509000013.tif247170TIFF2024543509000014.tif79170

[0513]

[0597] infectious disease

[0598] Treatment of infectious diseases will follow facility practice.

[0514]

[0599] For all serious infectious adverse events, a CBC with differentiation, quantitative immunoglobulins, and flow cytometry should be obtained within 1 week of onset.

[0515]

[0600] Patients who develop an active grade 1 or 2 infection during the divided dose period should withhold the day 8 injection until the infection has resolved.

[0516]

[0601] Patients who develop an active grade 3 or 4 infection during any of the divided doses will discontinue study treatment.

[0517]

[0602] Participants who show evidence of hepatitis reactivation will discontinue study treatment.

[0518]

[0603] Thrombocytopenia

[0604] All participants should be monitored for thrombocytopenia, and participants experiencing thrombocytopenia should undergo blood count monitoring until the grade 1 event resolves (platelet count ≥ 75,000 / μL). TIFF2024543509000015.tif108170

[0519]

[0605] Elevated liver enzymes and hepatic events

[0606] Participants with right upper quadrant pain and / or unexplained nausea or vomiting should undergo immediate LFTs and be re-evaluated before the next study drug dose.

[0520]

[0607] LFTs should be assessed periodically during the study and managed according to the guidelines in Table 12.

[0521]

[0608] Participants with elevated LFTs should be addressed as appropriate, taking into account concomitant medications, viral hepatitis, and toxic or neoplastic etiologies. TIFF2024543509000016.tif247170

[0522]

[0609] 5.1.3.4 Management of Prolonged QT Interval

[0610] Participants who develop any of the following should discontinue study medication unless there is a clear alternative cause for the change: Sustained (2 ECG measurements at least >30 minutes apart) QTcF (>500ms and >60ms longer than baseline) Sustained absolute QTcF (>515ms) Episodes of ventricular arrhythmia or new ECG findings of clinical concern

[0523]

[0611] If drug-induced arrhythmias, including persistent QTcF prolongation, are suspected based on ECG changes, cardiologist consultation and clinically appropriate management should be instituted. Management of participants with persistent QTcF prolongation should include close monitoring with repeat ECGs at least hourly until two consecutive ECGs show improvement, correction of electrolyte abnormalities, and discontinuation of other concomitant medications known to prolong the QT interval.

[0524]

[0612] 5.2 Safety parameters and definitions

[0613] Safety evaluation consists of monitoring and recording adverse events, including serious adverse events and adverse events of special interest, performing protocol-defined safety clinical evaluations, measuring protocol-defined vital signs, and performing any other protocol-defined tests considered important to the evaluation of the safety of the study.

[0525]

[0614] Certain events require immediate reporting to the sponsor, as outlined in 5.4.

[0526]

[0615] 5.2.1 Adverse Events

[0616] According to the ICH guideline on Good Clinical Practice, an adverse event is an untoward medical occurrence in a clinical trial patient receiving a medicinal product, regardless of attribution of cause. Thus, an adverse event can be any of the following: Any untoward or unexpected sign (including any abnormal clinical findings), symptom or illness temporarily associated with the use of a medicinal product, whether or not related to the medicinal product New or exacerbation of an existing condition (worsening of the character, frequency, or severity of a known condition) (see 5.3.5.9 and 5.3.5.10 for further details) Recurrence of intermittent symptoms (e.g., headaches) that were not present at baseline Deterioration in laboratory values ​​or other clinical studies (e.g., ECG, X-rays) that is related to symptoms or that leads to a change in study treatment or concomitant treatment or to discontinuation of the study drug Adverse events related to protocol-mandated interventions, including those occurring before study treatment allocation (e.g., screening invasive procedures such as biopsy).

[0527]

[0617] 5.2.2 Serious Adverse Events (must be reported immediately to the sponsor)

[0618] A serious adverse event is one that meets any of the following criteria: Fatal (i.e., the adverse event actually causes or leads to death) Life-threatening (i.e., in the investigator's opinion, the adverse event puts the participant at immediate risk of death). This does not include adverse events that could lead to death if they occurred in a more severe form or continued. Requiring or prolonged hospitalization (see 5.3.5.11) · Causes persistent or significant impairment / incapacity (i.e., the adverse event substantially interferes with the participant's ability to carry out normal life functions) Congenital / birth defects in newborns / infants born to mothers exposed to the study drug In the investigator's judgment, it is a serious medical event (e.g., it may put the participant at risk or may require medical / surgical intervention to prevent one of the outcomes listed above)

[0528]

[0619] The terms "severe" and "serious" are not synonymous. Severity refers to the intensity of the adverse event (e.g., rated as mild, moderate, or severe or by NCI CTCAE; see 5.3.3), and the event itself may be of relatively minor medical significance (e.g., severe headache with no further findings).

[0529]

[0620] Each adverse event recorded in the eCRF should be independently assessed for severity and seriousness.

[0530]

[0621] Serious adverse events are required to be reported immediately (i.e., within 24 hours of learning of the event; see 5.4.2 for reporting instructions) by the investigator to the sponsor.

[0531]

[0622] 5.2.3 Notable Adverse Events (those that must be reported immediately to the sponsor)

[0623] Notable adverse events are required to be reported immediately (i.e., within 24 hours of learning of the event; see 5.4.2 for reporting instructions) by the investigator to the sponsor. Notable adverse events in this study are: Potential cases of drug-induced liver injury, as defined by Hy's Law, including elevations in ALT or AST in combination with either elevated bilirubin or clinical jaundice. - Transmission of an infectious agent by the test drug is suspected, as defined below o Any organism, virus, or infectious particle, whether pathogenic or non-pathogenic (e.g., prion protein mediating transmissible spongiform encephalopathies), is considered an infectious agent. Transmission of an infectious agent may be suspected based on clinical signs or findings indicating infection in participants exposed to a medicinal product. This term applies only when contamination of the study drug is suspected. Adverse events meeting protocol-defined criteria for DLT (see 3.1.7.1). Grade ≥2 CRS Grade ≥2 neurological adverse events Grade ≥2 injection site reaction If HLH is suspected Febrile neutropenia (defined as at least grade 3) Grade ≥2 elevation of AST, ALT, or total bilirubin Disseminated intravascular coagulation of any grade (defined as at least grade 2) - Pneumonia or interstitial lung disease of any grade (excluding infectious pneumonia).

[0532]

[0624] 5.3 How and When Safety Parameters Are Obtained and Evaluated

[0625] The Investigator is responsible for ensuring that all Adverse Events (for definition, see 5.2.1) are recorded in the Adverse Events eCRF and reported to the Sponsor according to the instructions in this section and in 5.4-5.6. For each Adverse Event recorded in the Adverse Events eCRF, the Investigator will provide an assessment of severity (for severity criteria, see 5.2.2), severity (see 5.3.3), and causality (see 5.3.4).

[0533]

[0626] 5.3.1 Adverse Event Reporting Period

[0627] The investigator will request information about adverse events at each contact with the participant. All adverse events, whether reported by the participant or noted by study personnel, will be recorded in the participant's medical record and in the Adverse Events eCRF. After informed consent is obtained and before study drug initiation, only serious adverse events resulting from protocol-mandated interventions (e.g., invasive procedures such as biopsy, discontinuation of medication) need to be reported (see 5.4.2 for instructions on reporting serious adverse events). After study drug initiation, all adverse events will be reported until the end of the SFU (see 3.1). Instructions for reporting adverse events occurring after the adverse event reporting period are provided in 5.6.

[0534]

[0628] 5.3.2 Collection of Adverse Event Information

[0629] A consistent methodology of non-prompting questions should be used to collect adverse event information at all participant assessment time points. Examples of non-prompting questions include: · "How have you felt since your last visit?" "Have you had any new or changed health problems since your last visit?"

[0535]

[0630] 5.3.3 Adverse Event Severity Assessment: The Adverse Event Severity Assessment Scale of the NCI CTCAE (v5.0) is used to assess the severity of adverse events and the severity of individual signs and symptoms of CRS. CRS is graded using the ASTCT CRS Consensus Grading Criteria (Lee et al. 2019) (see Table 1). Table 13 is used to assess the severity of adverse events not specifically listed in the NCI CTCAE. TIFF2024543509000017.tif132170

[0536]

[0631] 5.3.4 Assessment of causality of adverse events

[0632] Investigators should use their knowledge of the participant, the circumstances surrounding the event, and their assessment of alternative possible causes to determine whether an adverse event is considered related to the study drug, and indicate "yes" or "no" accordingly. The following guidance should be taken into account (see also Table 14): -Temporal relationship of event onset to study drug initiation Consider the course of events, especially the impact of dose reductions, study drug discontinuation, or study drug reintroduction (if applicable) Known association of the event with the study drug or similar treatment Known association of the event with the disease being studied Participants had risk factors or were taking concomitant medications known to increase the occurrence of the event The presence of factors other than treatment that are known to be associated with the occurrence of the event TIFF2024543509000018.tif79170

[0537]

[0633] Adverse events should be considered related to mosunetuzumab unless they were attributable to other causes clearly identifiable by the investigator (e.g., worsening of documented underlying SLE, concom...

Claims

1. A medicament for treating a patient, comprising an effective amount of mosunetuzumab, (a) the patient has systemic lupus erythematosus; (b) mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, the first dosing cycle comprising a first dose and a second dose of mosunetuzumab, wherein the first dose is between about 1.6 mg and about 5 mg on day 1 of the cycle and the second dose is between about 15 mg and about 60 mg on day 8 of the cycle; (c) mosunetuzumab is administered subcutaneously; Medicine.

2. The pharmaceutical described in claim 1, wherein the first dose is 1.6 mg or 5 mg and the second dose is 15 mg, 45 mg, or 60 mg.

3. The method of claim 1, wherein at least one symptom of SLE is reduced.

4. A reduction in at least one symptom of SLE is measured using a patient's global impression of severity, a physician's global assessment, a reduction in antinuclear antibody titer, a reduction in anti-double-stranded DNA antibody titer, an increase in complement C3 levels, or an increase in complement C4 levels, and the reduction in at least one symptom is (a) a change from a previous response in the response of at least one step on the patient's global impression of severity, wherein the change is: (i) "very severe" to "severe"; (ii) "severe" to "moderate"; (iii) "moderate" to "mild"; or (iv) A change from "mild" to "none," or (b) a change in provider rating using the Physician Global Assessment, wherein the change is a reduction from the previous rating using the Physician Global Assessment, and the reduction from the previous rating using the Physician Global Assessment is ≧0.3 points from baseline; Including changes, The pharmaceutical composition according to claim 3.

5. The method of claim 1, further comprising administering to the patient a corticosteroid, cyclophosphamide, B-cell depletion therapy, or a calcineurin inhibitor.

6. 6. The pharmaceutical composition of claim 5, wherein the corticosteroid comprises hydrocortisone, cortisone acetate, prednisolone, dexamethasone, betamethasone, triamcinolone, beclomethasone, methylprednisolone, or prednisone; the B-cell depletion therapy comprises administering rituximab, ocrelizumab, ofatumumab, or obinutuzumab; or the calcineurin inhibitor comprises cyclosporine, tacrolimus, or vokolosporine.

7. A medicament for treating patients in a patient population, comprising an effective amount of mosunetuzumab; (a) the patient population has systemic lupus erythematosus; (b) mosunetuzumab is administered according to a dosing regimen comprising at least a first dosing cycle of about 8 days, the first dosing cycle comprising a first dose and a second dose of mosunetuzumab, wherein the first dose is between about 1.6 mg and about 5 mg on day 1 of the cycle and the second dose is between about 15 mg and about 60 mg on day 8 of the cycle; (c) mosunetuzumab is administered subcutaneously; Medicine.

8. The pharmaceutical described in claim 7, wherein the first dose is 1.6 mg or 5 mg and the second dose is 15 mg, 45 mg, or 60 mg.

9. The method of claim 7, wherein at least one symptom of SLE is reduced.

10. A reduction in at least one symptom of SLE is measured using a patient's global impression of severity, a physician's global assessment, a reduction in antinuclear antibody titer, a reduction in anti-double-stranded DNA antibody titer, an increase in complement C3 levels, or an increase in complement C4 levels, and the reduction in at least one symptom is (a) a change from a previous response in the response of at least one step on the patient's global impression of severity, wherein the change is: (i) "very severe" to "severe"; (ii) "severe" to "moderate"; (iii) "moderate" to "mild"; or (iv) A change from "mild" to "none," or (b) a change in provider rating using the Physician Global Assessment, wherein the change is a reduction from the previous rating using the Physician Global Assessment, and the reduction from the previous rating using the Physician Global Assessment is ≧0.3 points from baseline; Including changes, The pharmaceutical composition according to claim 9.

11. The method of claim 7, further comprising administering to the patient a corticosteroid, cyclophosphamide, B-cell depletion therapy, or a calcineurin inhibitor.

12. 12. The pharmaceutical composition of claim 11, wherein the corticosteroid comprises hydrocortisone, cortisone acetate, prednisolone, dexamethasone, betamethasone, triamcinolone, beclomethasone, methylprednisolone, or prednisone; the B-cell depletion therapy comprises administering rituximab, ocrelizumab, ofatumumab, or obinutuzumab; or the calcineurin inhibitor comprises cyclosporine, tacrolimus, or vokolosporin.

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