Pharmaceutical compositions comprising mixed antibodies for Anti-CTLA4 and Anti-PD1

Abstract

Provided are uses of a mixed antibody comprising anti-CTLA4 and anti-PD1 in combination with chemotherapeutic drugs, such as carboplatin / cisplatin and etoposide, for the treatment of small cell lung cancer.

Description

Pharmaceutical composition comprising mixed antibodies of anti-CTLA4 and anti-PD1 and therapeutic use thereof Technical Field

[0001] The present disclosure relates to the treatment of cancer, particularly small cell lung cancer, including immunotherapy and combination therapy. More specifically, the present disclosure relates to the use of a pharmaceutical composition comprising a mixed antibody of anti-CTLA4 and anti-PD1 for the treatment of small cell lung cancer. Background Art

[0002] According to GLOBOCAN 2020 data, lung cancer ranks second in cancer incidence worldwide, with 2.2 million cases, and ranks first in mortality, with 1.8 million deaths worldwide. In China, both incidence and mortality rates rank first, with 820,000 new cases and 710,000 deaths from lung cancer, respectively.

[0003] Small cell lung cancer (SCLC) accounts for approximately 15% of all lung cancer patients, and approximately two-thirds of SCLC patients present with extensive-stage SCLC (ES-SCLC) at the time of onset. Approximately 110,000 new cases of SCLC are diagnosed in China each year, including over 60,000 cases of ES-SCLC.

[0004] ES-SCLC is sensitive to chemotherapy, with objective response rates as high as 40-70%. However, the duration of response is short, with median PFS <6 months, mOS <12 months, and a five-year survival rate of less than 6%, resulting in an extremely poor prognosis. Although immunotherapy combined with chemotherapy can prolong overall survival in ES-SCLC, efficacy remains suboptimal. Currently, immunosuppressants available in China for the first-line treatment of extensive-stage small cell lung cancer include atezolizumab, durvalumab, and serotonin. However, atezolizumab and durvalumab are expensive and have limited access. Pharmacoeconomic analyses have shown that atezolizumab plus chemotherapy or durvalumab plus chemotherapy do not offer a cost-effectiveness advantage over chemotherapy alone as a first-line treatment for ES-SCLC. Accessible first-line treatments for ES-SCLC in China remain limited, and there is an urgent need to develop more effective drugs to enrich the treatment landscape and prolong patient survival.

[0005] ZPML265 is a hybrid antibody drug formulation, a dual-target immune (abbreviated as dual-immune) therapeutic drug, composed of a recombinant humanized IgG1 monoclonal antibody targeting human CTLA4 and a recombinant humanized IgG4 monoclonal antibody targeting human PD1. These two different antibodies are produced by a single host cell. This hybrid antibody can simultaneously and specifically bind to CTLA4 and PD1, thereby blocking the two immune checkpoint signaling pathways of CTLA-4 and B7-1 / B7-2, and PD-1 and PD-L1. This relieves the inhibitory effects of these two pathways on T lymphocytes, restores their functional activity and anti-tumor immune response, and thus enables the body to fight and kill tumors.

[0006] Although combining chemotherapy with anti-PD-(L)1 immunotherapy can prolong the overall survival of ES-SCLC, the efficacy is still poor and there is still a very urgent clinical need. We hope that more and better drugs can bring longer survival benefits to the majority of patients with advanced SCLC.

[0007] SUMMARY OF THE INVENTION

[0008] The technical problem to be solved by the present disclosure is to provide an immunotherapy to fill the clinical gap of the lack of dual-target immune (dual-immune) therapeutic drugs for small cell lung cancer in the world, thereby solving such unmet clinical needs.

[0009] The present disclosure provides a pharmaceutical composition for treating small cell lung cancer, comprising an effective amount of mixed antibodies of anti-CTLA4 and anti-PD1.

[0010] In some embodiments, the pharmaceutical composition further comprises a pharmaceutically acceptable carrier.

[0011] In some embodiments, the pharmaceutical composition further comprises an additional therapeutic agent, including but not limited to chemotherapeutic agents (chemotherapeutic drugs), cytotoxic agents, radiotherapeutic agents, cancer vaccines, tumor reducing agents, targeted anti-cancer agents, anti-angiogenic agents, biological response modifiers, cytokines, hormones, anti-metastatic agents, and immunotherapeutic agents.

[0012] In some embodiments, the additional therapeutic agent is a chemotherapeutic drug, preferably a combination of carboplatin / cisplatin and etoposide.

[0013] Therefore, the present disclosure also preferably provides a pharmaceutical composition for treating small cell lung cancer, which contains an effective amount of a mixed antibody of anti-CTLA4 and anti-PD1 and a chemotherapeutic drug.

[0014] The present disclosure also particularly preferably provides a pharmaceutical composition for treating small cell lung cancer, which contains an effective amount of a mixed antibody of anti-CTLA4 and anti-PD1, carboplatin / cisplatin and etoposide.

[0015] In some embodiments, the hybrid antibody is produced by a single host cell that contains nucleic acids encoding two different antibodies, anti-CTLA4 and anti-PD1, wherein the sequences of the anti-CTLA4 antibody heavy chain HCDR1, HCDR2 and HCDR3 are shown in SEQ ID NOs: 1, 2, and 3, respectively, the sequences of the anti-CTLA4 antibody light chain LCDR1, LCDR2 and LCDR3 are shown in SEQ ID NOs: 4, 5, and 6, respectively, the sequences of the anti-PD1 antibody heavy chain HCDR1, HCDR2 and HCDR3 are shown in SEQ ID NOs: 9, 10, and 11, respectively, and the sequences of the anti-PD1 antibody light chain LCDR1, LCDR2 and LCDR3 are shown in SEQ ID NOs: 12, 13, and 14, respectively.

[0016] In some embodiments, the heavy chain variable region sequence of the anti-CTLA4 antibody is shown in SEQ ID NO: 7, the light chain variable region sequence of the anti-CTLA4 antibody is shown in SEQ ID NO: 8, the heavy chain variable region sequence of the anti-PD1 antibody is shown in SEQ ID NO: 15, and the light chain variable region sequence of the anti-PD1 antibody is shown in SEQ ID NO: 16.

[0017] In some embodiments, the heavy chain sequence of the anti-CTLA4 antibody is shown in SEQ ID NO: 17, the light chain sequence of the anti-CTLA4 antibody is shown in SEQ ID NO: 18, the heavy chain sequence of the anti-PD1 antibody is shown in SEQ ID NO: 19, and the light chain sequence of the anti-PD1 antibody is shown in SEQ ID NO: 20.

[0018] Preferably, the small cell lung cancer is extensive-stage small cell lung cancer.

[0019] The dosage of the mixed antibody is 5 mg / kg, administered once every three weeks, by intravenous infusion on the first day, and a cycle of 21 days.

[0020] and chemotherapy drugs carboplatin at a target AUC of 5 mg / min / mL or cisplatin at a dose of 75 mg / m 2 , administered by intravenous infusion on day 1; etoposide dose was 100 mg / m 2 , administered by intravenous infusion on days 1, 2, and 3, with a cycle of 21 days.

[0021] Furthermore, after 4-6 treatment cycles, the mixed antibody is still used for maintenance treatment once every 3 weeks, with a dose of 5 mg / kg, administered by intravenous infusion on the first day, with a cycle of 21 days until disease progression.

[0022] At the same time, the present disclosure also provides a method for treating small cell lung cancer, which comprises administering a pharmaceutical composition to a subject, wherein the pharmaceutical composition is the aforementioned mixed antibody comprising an effective amount of anti-CTLA4 and anti-PD1.

[0023] The present disclosure also preferably provides a method for treating small cell lung cancer, comprising administering to a subject a pharmaceutical composition, wherein the pharmaceutical composition is the aforementioned mixed antibody comprising an effective amount of anti-CTLA4 and anti-PD1 and a chemotherapy drug.

[0024] The present disclosure also particularly preferably provides a method for treating small cell lung cancer, comprising administering to a subject a pharmaceutical composition, wherein the pharmaceutical composition is the aforementioned mixed antibody comprising an effective amount of anti-CTLA4 and anti-PD1, carboplatin / cisplatin, and etoposide.

[0025] The results of a phase I clinical study of the hybrid antibody disclosed herein as a single drug showed that the efficacy of the 26 patients with small cell lung cancer enrolled was definite and the safety was good. At the same time, the clinical study of the hybrid antibody of the present disclosure combined with chemotherapy in small cell lung cancer that has been carried out has also preliminarily shown a synergistic anti-tumor effect and demonstrated a better clinical efficacy. Therefore, the hybrid antibody or the combination of the hybrid antibody and chemotherapy drugs (such as carboplatin / cisplatin + etoposide) provided by the present disclosure is expected to have controllable safety and good patient compliance for the medical treatment of extensive-stage small cell lung cancer, and can largely fill the gap in the international approval of dual-target immunotherapy drugs for small cell lung cancer, and solve the urgent unmet clinical needs. DETAILED DESCRIPTION

[0026] the term

[0027] All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference.

[0028] Before describing the present disclosure in detail below, it should be understood that the present disclosure is not limited to the specific methodologies, protocols and reagents described herein, as these may vary. It should also be understood that the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of the present disclosure. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present disclosure belongs.

[0029] Certain embodiments disclosed herein include numerical ranges, and certain aspects of the present disclosure may be described in terms of ranges. Unless otherwise stated, it should be understood that numerical ranges or descriptions in terms of ranges are intended for simplicity and convenience and should not be considered as strict limitations on the scope of the present disclosure. Therefore, descriptions in terms of ranges should be considered to specifically disclose all possible subranges and all possible specific numerical points within the range, as these subranges and numerical points have been clearly stated herein. Regardless of the width of the numerical value, the above principles apply equally. When describing in terms of ranges, the range includes the endpoints of the range.

[0030] When referring to a measurable value such as an amount, a temporal duration, etc., the term "about" is meant to include variations of ±20%, or in some cases ±10%, or in some cases ±5%, or in some cases ±1%, or in some cases ±0.1% of the specified value.

[0031] As used herein, the three-letter and one-letter codes for amino acids are as described in J. Biol. Chem, 243, p3558 (1968).

[0032] The term "antibody" as used herein typically refers to a Y-shaped tetrameric protein comprising two heavy (H) polypeptide chains (HC) and two light (L) polypeptide chains (LC) held together by covalent disulfide bonds and non-covalent interactions. Natural IgG antibodies have this structure. Each light chain consists of a variable domain (VL) and a constant domain (CL). Each heavy chain comprises a variable domain (VH) and a constant region (CH).

[0033] Five major classes of antibodies are known in the art: IgA, IgD, IgE, IgG, and IgM. The corresponding heavy chain constant domains are called α, δ, ε, γ, and μ, respectively. IgG and IgA can be further divided into different subclasses, for example, IgG can be divided into IgG1, IgG2, IgG3, and IgG4, and IgA can be divided into IgA1 and IgA2. The light chains of antibodies from any vertebrate species can be assigned to one of two clearly distinct types, called κ and λ, based on the amino acid sequence of their constant domains.

[0034] The term "variable region" or "variable domain" shows significant changes in the amino acid composition from one antibody to another, and is primarily responsible for antigen recognition and binding. The variable region of each light chain / heavy chain pair forms an antibody binding site, so that a complete IgG antibody has two binding sites (i.e., it is bivalent). The variable region (VH) of the heavy chain and the variable region (VL) of the light chain each contain three regions with extreme variability, referred to as hypervariable regions (HVRs), or more generally, referred to as complementary determining regions (CDRs). VH and VL each have four skeleton regions FR (or framework regions), represented by FR1, FR2, FR3, and FR4, respectively. Therefore, CDR and FR sequences typically appear in the following sequence of a heavy chain variable domain (VH) (or light chain variable domain (VL)): FR1-HCDR1 (LCDR1)-FR2-HCDR2 (LCDR2)-FR3-HCDR3 (LCDR3)-FR4.

[0035] The types of "antibodies" in a broad sense may include polyclonal antibodies, monoclonal antibodies, chimeric antibodies, humanized antibodies and primatized antibodies, CDR-grafted antibodies, human antibodies (including recombinantly produced human antibodies), recombinantly produced antibodies, intracellular antibodies, multispecific antibodies, bispecific antibodies, single-chain antibodies, monovalent antibodies, multivalent antibodies, single-domain antibodies, nanobodies, synthetic antibodies (including muteins and variants thereof), etc.

[0036] The term "monoclonal antibody" (or "mAb") refers to a substantially homogeneous antibody produced by a single cell clone that is directed against a specific antigenic epitope. Monoclonal antibodies can be prepared using a variety of techniques known in the art, including hybridoma technology, recombinant technology, phage display technology, transgenic animals, synthetic technology, or a combination of these techniques.

[0037] It should be noted that the division of the CDRs and FRs in the antibody variable regions of the present disclosure is determined according to the Kabat definition. Other naming and numbering systems, such as Chothia, IMGT, or AHo, are also known to those skilled in the art. Therefore, humanized antibodies containing one or more CDRs derived from any naming system based on the antibody sequences of the present disclosure are clearly within the scope of the present disclosure.

[0038] The term "antigen" refers to a substance that is recognized and specifically bound by an antibody or antibody binding fragment. In a broad sense, an antigen can include any immunogenic fragment or determinant of a selected target, including a single epitope, multiple epitopes, a single domain, multiple domains, or a complete extracellular domain (ECD) or protein.

[0039] The terms "polypeptide," "peptide," and "protein" are used interchangeably herein to refer to polymers of amino acids of any length. The polymer may be linear, cyclic, or branched, it may contain modified amino acids, particularly conservatively modified amino acids, and it may be interrupted by non-amino acids. The term also includes amino acid polymers that have been modified, for example, by glycosylation, lipidation, acetylation, phosphorylation, methylation, and the like.

[0040] As used herein, the term "hybrid antibody" refers to an antibody containing a limited number of primary antibody species, optionally no more than two, three, four, five, six, seven, eight, nine, or ten, produced from host cells (optionally cells from a single host cell line) that have been transfected with DNA encoding at least two different antibodies (optionally full-length primate IgG antibodies) with different binding specificities. In some embodiments, DNA encoding at least two different heavy chains (HCs) and at least two different light chains (LCs) can be introduced into the same host cell. For example, a host cell can be transfected with DNA encoding at least two but no more than four different antibodies with different binding specificities. In some embodiments, the sequences of all transfected DNA encoding HCs and LCs can be mutated to alter the amino acid sequence of the antibody, thereby disfavoring non-homologous HC / LC pairing and strongly favoring homologous HC / LC pairing. In the case of introducing two different HCs into the host cell, one or both of the two different HCs can be optionally altered to disfavor heterodimer formation. In some embodiments, only one heavy chain is altered to prevent heterodimer formation. In some embodiments, when DNA encoding only two different antibodies is introduced into a host cell, only one of the antibodies encoded by the DNA comprises one or more partner-directed changes that favor cognate HC / LC pairing, while the other antibody does not comprise such changes. In some embodiments, the host cell produces only two major antibody species, wherein each HC predominantly pairs with its cognate LC, and most antibodies are tetramers containing two heavy chains having the same amino acid sequence and two light chains having the same amino acid sequence (see PCT / US2017 / 030676).

[0041] The term "pharmaceutical composition" refers to a formulation or combination of formulations containing one, two, or more active ingredients, which allows the active ingredients contained therein to exist in a biologically effective form and does not contain additional ingredients that are unacceptably toxic to the subject to which the formulation is administered. When a "pharmaceutical composition" is present as a combination of separate formulations containing two or more different active ingredients, they can be administered simultaneously, sequentially, separately, or at intervals, with the goal of exerting the biological activities of the multiple active ingredients for combined treatment of a disease.

[0042] The term "pharmaceutical carrier" or "pharmaceutically acceptable carrier" refers to a diluent, adjuvant (eg, Freund's adjuvant (complete and incomplete)), excipient, or vehicle with which the therapeutic agent is administered.

[0043] The term "effective amount" refers to a dose of a pharmaceutical formulation comprising an active ingredient of the present disclosure that produces the desired effect in a treated patient after administration to the patient in a single or multiple doses. The effective amount can be readily determined by the attending physician, who is skilled in the art, by considering a variety of factors such as ethnic differences; weight, age, and health status; the specific disease involved; the severity of the disease; the response of the individual patient; the specific antibody administered; the mode of administration; the bioavailability characteristics of the administered formulation; the selected dosing regimen; and the use of any concomitant therapy.

[0044] The terms "host cell," "host cell line," and "host cell culture" are used interchangeably and refer to cells into which exogenous nucleic acid has been introduced, including the progeny of such cells. Host cells include "transformants" and "transformed cells," which include the primary transformed cell and progeny derived therefrom, without regard to the number of passages. Progeny may not be completely identical in nucleic acid content to the parent cell, but may contain mutations. Mutant progeny that have the same function or biological activity as screened or selected for in the originally transformed cell are included herein.

[0045] The term "transfection" as used herein refers to the introduction of exogenous nucleic acid into eukaryotic cells. Transfection can be achieved by various means known in the art, including electroporation, microinjection, liposome fusion, etc.

[0046] The terms "nucleic acid molecule encoding," "coding DNA sequence," and "coding DNA" refer to the order of deoxyribonucleotides along a deoxyribonucleic acid chain. The order of these deoxyribonucleotides determines the order of amino acids along a polypeptide (protein) chain. Thus, a nucleic acid sequence encodes an amino acid sequence.

[0047] Methods for producing and purifying antibodies and antigen-binding fragments are well known and can be found in the prior art, such as the Cold Spring Harbor Manual of Antibody Laboratory Techniques, Chapters 5-8 and 15. The engineered antibodies or antigen-binding fragments thereof disclosed herein can be prepared and purified using conventional methods. For example, cDNA sequences encoding heavy and light chains can be cloned and recombined into expression vectors. The recombinant immunoglobulin expression vector can be stably transfected into CHO cells. Stable clones are obtained by expressing antibodies that specifically bind to human antigens. Positive clones are expanded in serum-free culture medium in a bioreactor to produce antibodies. The culture fluid that secretes the antibodies can be purified and collected using conventional techniques. The antibodies can be filtered and concentrated using conventional methods. Soluble mixtures and polymers can also be removed using conventional methods, such as molecular sieves and ion exchange.

[0048] As used herein, the term "individual" or "subject" refers to any animal, such as a mammal or marsupial. Individuals of the present disclosure include, but are not limited to, humans, non-human primates (e.g., cynomolgus or rhesus monkeys or other types of macaques), mice, pigs, horses, donkeys, cattle, sheep, rats, and any type of poultry.

[0049] As used herein, the terms "disease," "condition," or "disorder" refer to any change or disorder that damages or interferes with the normal function of a cell, tissue, or organ. For example, "disease" includes, but is not limited to, tumors, pathogen infection, autoimmune diseases, T-cell dysfunction, or immune tolerance deficiency (e.g., transplant rejection).

[0050] As used herein, the term "tumor" refers to a disease characterized by the pathological proliferation of cells or tissues, and their subsequent migration or invasion of other tissues or organs. Tumor growth is typically uncontrolled and progressive, without inducing or inhibiting normal cell proliferation. Tumor includes "cancer" and refers broadly to all malignant tumors.

[0051] As used herein, the term "treatment" refers to clinical intervention aimed at altering the course of a disease in an individual or cell, and can be either preventative or interventional in the clinical pathological process. Therapeutic effects include, but are not limited to, preventing the onset or recurrence of a disease, alleviating symptoms, reducing any direct or indirect pathological consequences of a disease, preventing metastasis, slowing the progression of a disease, improving or relieving the condition, and alleviating or improving the prognosis.

[0052] The term "combination" as used herein refers to a treatment regimen that provides at least two or more different therapies to achieve a specified therapeutic effect. The therapies can be physical, such as radiotherapy, or chemical, such as administering a drug to a subject, and the drug also includes a combination drug. "Combination drug" refers to a combination of two or more pharmaceutical preparations, each of which has an active ingredient, that need to be used in combination when administered to a subject. The active ingredients can be mixed together to form a single dosing unit, or they can be independently administered as dosing units and used separately; when administered, different pharmaceutical preparations can be administered essentially synchronously, simultaneously or sequentially.

[0053] Overall survival (OS) is defined as the time from the start of study treatment to death from any cause. Patients who were still in follow-up at the cut-off date were censored based on the analysis cut-off date. Subjects lost to follow-up were censored based on the date of last contact.

[0054] Progression-free survival (PFS) refers to the time from the start of study treatment to the first imaging assessment of disease progression or death from any cause (whichever occurs first).

[0055] The objective response rate (ORR) was defined as the best confirmed ORR during the study period, including both complete responses (CR) and partial responses (PR). According to RECIST v1.1, additional imaging was required to confirm the first occurrence of a PR or CR at ≥4 weeks.

[0056] Disease control rate (DCR) refers to the percentage of cases with the best efficacy evaluation as "CR+PR+SD".

[0057] Complete remission (CR): All target lesions disappear and the short diameter of all pathological lymph nodes (including target nodules and non-target nodules) must be reduced to <10mm.

[0058] Partial response (PR): The sum of the target lesion diameters decreased by at least 30% compared with the baseline level.

[0059] Disease progression (PD): The minimum value of the sum of all target lesion diameters measured during the entire experimental study is used as a reference, and the relative increase in the diameter sum is at least 20% (if the baseline measurement value is the minimum, the baseline value is used as a reference); in addition, the absolute value of the diameter sum must increase by at least 5 mm (the appearance of one or more new lesions is also considered as disease progression).

[0060] Stable disease (SD): The target lesion has not decreased to the level of PR, nor increased to the level of PD, but is somewhere in between. The minimum sum of the diameters can be used as a reference for research.

[0061] Duration of response (DOR) was defined as the time from the first tumor assessment as CR or PR (whichever was recorded first) to the first assessment as PD or death.

[0062] Treatment-emergent adverse events (TEAEs) refer to adverse events that occur during treatment.

[0063] Treatment-related adverse events (TRAEs) are adverse events related to study drugs that occur during treatment.

[0064] A serious adverse event (SAE) refers to an adverse medical event such as death, life-threatening, permanent or severe disability or loss of function, the need for hospitalization or prolonged hospitalization, and congenital anomalies or birth defects that occurs in a subject after receiving an investigational drug.

[0065] Example

[0066] The present disclosure is further described below with reference to specific examples. It should be understood that these examples are only used to illustrate the present disclosure and are not intended to limit the scope of the present disclosure.

[0067] Example 1 Obtaining the hybrid antibody ZPML265

[0068] A hybrid antibody produced by a single host cell line was prepared (see PCT / US2017 / 030676). The hybrid antibody contains two active ingredients: a recombinant humanized IgG1 monoclonal antibody targeting human CTLA4 and a recombinant humanized IgG4 monoclonal antibody targeting human PD1. The hybrid antibody can specifically bind to both human CTLA4 and PD1. After the two antibodies are simultaneously expressed in a single host cell line, they are collected, purified, and combined with a pharmaceutically acceptable carrier to form a single hybrid antibody pharmaceutical preparation, ZPML265. The amino acid sequences of the anti-CTLA4 antibody and the anti-PD1 antibody are shown in Table 1 below.

[0069] Table 1 Amino acid sequences of the components of the mixed antibody ZPML265

[0070] Example 2 Efficacy and safety of ZPML265 monotherapy in the treatment of extensive-stage small cell lung cancer

[0071] Dosage:

[0072] In a Phase I clinical study conducted in China, 26 patients with pathologically confirmed extensive-stage small cell lung cancer were enrolled. The patients were over 18 years old, had an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, and had an expected survival of 3 months or more. The functional level of vital organs before the first use of the investigational drug was:

[0073] 1) Absolute neutrophil count ≥1.5×10 9 / L;

[0074] 2) Platelets ≥75×10 9 / L;

[0075] 3) Hemoglobin ≥90 g / L;

[0076] 4) serum albumin ≥30 g / L;

[0077] 5) Alanine aminotransferase (AST) and aspartate aminotransferase (ALT) ≤ 2.5 × upper limit of normal reference value (ULN) (for patients with liver cancer or liver metastasis, ≤ 5 × ULN is allowed);

[0078] 6) Total bilirubin ≤1.5×ULN (≤3×ULN is allowed for patients with Gilbert syndrome);

[0079] 7) International normalized ratio (INR) ≤ 1.5; activated partial thromboplastin time (APTT) ≤ 1.5 × ULN;

[0080] 8) Serum creatinine ≤ 1.5 × ULN. If the subject's creatinine level is > 1.5 × ULN, creatinine clearance (CrCl) ≥ 50 mL / min (calculated according to the Cockcroft-Gault formula);

[0081] 9) Left ventricular ejection fraction (LVEF)>50%.

[0082] Dosage regimen: ZPML265 is administered at a dose of 5 mg / kg via intravenous infusion once every three weeks.

[0083] Effectiveness Results:

[0084] Efficacy data from ZPML265 monotherapy in 26 patients with extensive-stage small cell lung cancer showed a confirmed ORR of 23.1% and a DCR of 34.6%. Among 12 patients with SCLC who had received ≥1 line of prior therapy and no immunotherapy, 3 achieved a PR as their best response assessment, while 2 had SD. The confirmed ORR was 25.0% and the confirmed DCR was 41.7%. Among 11 patients with SCLC who had received ≥1 line of prior therapy and immunotherapy, 2 achieved a PR as their best response assessment, while 1 had SD. The confirmed ORR was 18.2% and the confirmed DCR was 27.3%. This study demonstrates the promising therapeutic effect of ZPML265 monotherapy in the treatment of SCLC.

[0085] Safety results:

[0086] Safety data were compiled from 609 subjects treated with ZPML265. As of May 31, 2022, 546 (89.7%) patients experienced TEAEs and 451 (74.1%) patients experienced TEAEs related to ZPML265. Grade ≥3 TEAEs and SAEs were reported in 187 (30.7%) and 156 (25.6%) patients, respectively, and Grade ≥3 TEAEs related to ZPML265 and SAEs related to ZPML265 were reported in 102 (16.7%) and 75 (12.3%) patients, respectively.

[0087] TRAEs with an incidence of ≥10% included rash (17.6%), pruritus (12.3%), hypothyroidism (11.3%), hyperthyroidism (10.3%), anemia (10%), and increased aspartate aminotransferase (10%). Grade ≥3 TRAEs occurred in 16.7% of patients, and TRAEs with an incidence of ≥1% included anemia (2.3%), increased aspartate aminotransferase (1.1%), and increased alanine aminotransferase (1.0%).

[0088] Compared with ZPML265 monotherapy, another meta-analysis that summarized 2,664 cases of Nivolumab combined with Ipilimumab showed that the overall incidence of treatment-related serious adverse events was 29.6%, and the incidence of grade ≥3 TRAE was 39.9%, which were higher than the relevant data of ZPML265 monotherapy.

[0089] Existing data show that the treatment safety is acceptable and no new safety signals have been found compared with other immunotherapy drugs.

[0090] in conclusion:

[0091] Overall, ZPML265 monotherapy has shown promising therapeutic effects in the treatment of extensive-stage small cell lung cancer. In terms of safety, the TRAE incidence is similar to that of anti-PD-(L)1 monotherapy, and lower than that of the dual-drug combination therapy of Nivolumab + Ipilimumab. That is, while ensuring the effectiveness of the drug, the safety is better than the existing clinical solutions in the existing technology.

[0092] Example 3 A Phase II Clinical Study Evaluating ZPML265 Combined with Carboplatin and Etoposide as First-Line Therapy for Extensive-Stage Small Cell Lung Cancer

[0093] A Phase II clinical study of ZPML265 combined with carboplatin and etoposide as the first-line treatment for extensive-stage small cell lung cancer enrolled patients with histologically or cytologically confirmed extensive-stage small cell lung cancer. Patients were aged ≥18 and ≤75 years, regardless of gender. ECOG performance status score was 0-1. Expected survival was ≥12 weeks. Prior to the first dose of the investigational drug, the functional status of vital organs must meet the following requirements:

[0094] 1) Complete blood count (no blood transfusion or use of hematopoietic stimulating factor drugs within 14 days before laboratory examination): white blood cell count ≥ 3.0 × 10 9 / L; absolute neutrophil count ≥1.5×10 9 / L; platelet ≥100×10 9 / L; hemoglobin ≥90g / L;

[0095] 2) Liver function: For subjects without liver metastasis, aspartate aminotransferase ≤ 2.5 × ULN; alanine aminotransferase ≤ 2.5 × ULN; for subjects with liver metastasis, ALT and AST ≤ 5 × ULN; serum total bilirubin ≤ 1.5 × ULN (for Gilbert syndrome, total bilirubin ≤ 3.0 mg / dL);

[0096] 3) Renal function: serum creatinine ≤1.5×ULN or creatinine clearance ≥50 mL / min;

[0097] 4) Coagulation function: international normalized ratio ≤ 1.5 × ULN, activated partial thromboplastin time ≤ 1.5 × ULN (only applicable to patients not currently receiving anticoagulant therapy; patients currently receiving anticoagulant therapy should receive a stable dose of anticoagulant therapy);

[0098] 5) Others: Lipase ≤ 1.5 × ULN (patients with lipase > 1.5 × ULN and no clinical or imaging evidence of pancreatitis can be enrolled); Amylase ≤ 1.5 × ULN (patients with amylase > 1.5 × ULN and no clinical or imaging evidence of pancreatitis can be enrolled); Alkaline phosphatase ≤ 2.5 × ULN; for subjects with liver or bone metastasis, ALP ≤ 5 × ULN.

[0099] Dosage regimen:

[0100] ZPML265 was administered at a dose of 5 mg / kg via intravenous infusion once every three weeks.

[0101] Carboplatin was administered as an intravenous infusion on day 1 with a target AUC of 5 mg / min / mL, and etoposide was administered at a dose of 100 mg / m 2 , administered by intravenous infusion on days 1, 2, and 3, with a cycle of 21 days, and 4-6 cycles of administration.

[0102] Effectiveness Results:

[0103] ZPML265 monotherapy combined with chemotherapy was used to treat 40 patients with extensive-stage small cell lung cancer. The efficacy analysis was based on 39 evaluable patients. As of January 16, 2023, the confirmed ORR was 89.7% (35 / 39), the best overall tumor assessment of 35 subjects (92.1%) was PR, the best overall tumor assessment of 3 subjects (7.7%) was SD, and 1 subject (2.6%) was PD. The overall DCR was 97.4% (38 / 39), the 3-month PFS rate was 94.8%, and the median PFS was 5.7 months (95% confidence interval: 5.4-7.1 months).

[0104] Currently, the ORR of ZPML265 combined with chemotherapy is better than the PD-(L)1 inhibitor + chemotherapy data in similar studies (ATEZILIZUMAB vs. chemotherapy ORR: 60.2%, DURUMAB vs. chemotherapy ORR: 68%).

[0105] Safety results:

[0106] All 40 subjects received at least one dose of ZPML265. As of January 16, 2023, the median duration of ZPML265 treatment was 25.64 weeks (range: 3.0-38.9 weeks). All 40 subjects (100%) who entered the safety analysis set experienced at least one TEAE, of which 80% experienced adverse events related to ZPML265. TRAEs with an incidence of ≥30% were anemia (45%), decreased platelet count (35.0%), decreased neutrophil count (30.0%), decreased white blood cell count (30.0%), and nausea (30.0%). Among them, 15 patients (37.5%) experienced TEAEs of grade 3 or higher, of which TRAEs with an incidence of ≥10% were decreased neutrophil count (20.0%) and decreased platelet count (10.0%). No TRAEs resulted in death.

[0107] No TEAEs led to permanent discontinuation of ZPML265 or chemotherapy.

[0108] Safety data were comparable to those of single-target immunotherapy (single immunotherapy) combined with chemotherapy. Common adverse events were hematologic toxicities, common toxicities associated with the chemotherapy drugs etoposide and carboplatin. The incidence of grade 3-4 events was 90%, similar to the 82.5% incidence of serotonin in the ASTRUM-005 study.

[0109] in conclusion:

[0110] Overall, ZPML265 combined with chemotherapy showed promising therapeutic effects as a first-line treatment for extensive-stage small cell lung cancer. In terms of safety, the incidence of grade 3-4 TRAEs was similar to that of anti-PD-1 monotherapy. That is, while ensuring the effectiveness of the drug, the safety is comparable to existing clinical regimens in the existing technology.

[0111] Example 4: Phase III clinical study evaluating ZPML265 combined with carboplatin / cisplatin and etoposide as first-line treatment for extensive-stage small cell lung cancer

[0112] A Phase III clinical study of ZPML265 in combination with carboplatin / cisplatin and etoposide as the first-line treatment for extensive-stage small cell lung cancer enrolled patients with histologically or cytologically confirmed extensive-stage small cell lung cancer. Patients were aged 18-75 years, male or female, with an ECOG performance status of 0-1. The expected survival was ≥12 weeks. Prior to the first dose of the study drug, the functional status of vital organs must meet the following requirements:

[0113] (1) Routine blood test (no blood transfusion or use of hematopoietic stimulating factor drugs within 14 days before the screening laboratory test):

[0114] a) White blood cell count (WBC) ≥4.0×109 / L;

[0115] b) Absolute neutrophil count (ANC) ≥ 2.0 × 10 9 L;

[0116] c) Platelet (PLT) ≥100×10 9 / L;

[0117] d) Hemoglobin (HGB) ≥9.0 g / dL;

[0118] (2) Liver function: aspartate transferase (AST) ≤ 2.5 × ULN for patients without liver metastasis; alanine aminotransferase (ALT) ≤ 2.5 × ULN; for patients with liver metastasis, ALT and AST ≤ 5 × ULN; serum total bilirubin (TBIL) ≤ 1.5 × ULN (excluding Gilbert syndrome, where total bilirubin ≤ 3.0 mg / dL);

[0119] (3) Renal function: serum creatinine ≤ 1.5 × ULN or creatinine clearance rate (CrCl) ≥ 50 mL / minute, and urine protein < 2+. If urine protein is 2+, additional 24-hour urine protein measurement or random urine sample collection is required to assess the urine protein / creatinine ratio. If the 24-hour urine protein measurement is < 1 g or the urine protein / creatinine ratio is < 2, the patient can be enrolled;

[0120] (4) Coagulation function: international normalized ratio (INR) ≤ 1.5 × ULN, activated partial thromboplastin time (APTT) ≤ 1.5 × ULN (only applicable to patients who are not currently receiving anticoagulant therapy; patients who are currently receiving anticoagulant therapy should receive a stable dose of anticoagulant therapy);

[0121] (5) Others: Alkaline phosphatase (ALP) ≤ 2.5 × ULN; for patients with liver metastasis or bone metastasis, ALP ≤ 5 × ULN.

[0122] Dosage regimen:

[0123] 1) Experimental group: ZPML265 + carboplatin / cisplatin + etoposide:

[0124] The intensive treatment period is 21 days as one treatment cycle, and the treatment lasts for 4-6 cycles;

[0125] ZPML265, 5 mg / kg, day 1 (D1), intravenous (IV) infusion, Q3W;

[0126] Carboplatin AUC 5 or cisplatin 75 mg / m 2 , D1, IV infusion, Q3W;

[0127] Etoposide 100 mg / m 2 , D1, 2, 3, IV infusion, Q3W;

[0128] Patients without disease progression received maintenance treatment with ZPML265 monotherapy, 5 mg / kg, D1, IV infusion, Q3W.

[0129] 2) Control group: Adebelimumab + carboplatin + etoposide:

[0130] The intensive treatment period is 21 days as one treatment cycle, and the treatment lasts for 4-6 cycles;

[0131] Adebelimumab, 20 mg / kg, D1, IV infusion, Q3W;

[0132] Carboplatin AUC 5, D1, IV infusion, Q3W;

[0133] Etoposide 100 mg / m 2 , D1, 2, 3, IV infusion, Q3W;

[0134] Patients without disease progression received maintenance therapy with adebelimumab monotherapy, 20 mg / kg, D1, IV infusion, Q3W.

[0135] In addition, after disease progression, for patients in the trial group, if the researchers believe that continued treatment with ZPML265 may still provide clinical benefit, ZPML265 can be used in combination with second-line chemotherapy. That is, patients can choose to enter the following second-line treatment:

[0136] Experimental group: chemotherapy + ZPML265, 21 days as one treatment cycle

[0137] Control group: chemotherapy, 21 days as a treatment cycle

[0138] The chemotherapy regimen was selected according to the latest CSCO guidelines.

[0139] The embodiments of the present disclosure described above are merely exemplary, and any person skilled in the art will recognize or be able to determine the equivalents of numerous specific compounds, materials, and operations without requiring undue experimentation. All such equivalents are within the scope of the present disclosure and are encompassed by the claims.

Claims

1. A pharmaceutical composition for treating small cell lung cancer, comprising an effective amount of a mixed antibody of anti-CTLA4 and anti-PD1 and a chemotherapeutic drug, wherein the mixed antibody is produced by a single host cell containing nucleic acids encoding two different antibodies, anti-CTLA4 and anti-PD1, wherein: The sequences of the anti-CTLA4 antibody heavy chain HCDR1, HCDR2 and HCDR3 are shown in SEQ ID NOs: 1, 2 and 3, respectively; the sequences of the anti-CTLA4 antibody light chain LCDR1, LCDR2 and LCDR3 are shown in SEQ ID NOs: 4, 5 and 6, respectively; the sequences of the anti-PD1 antibody heavy chain HCDR1, HCDR2 and HCDR3 are shown in SEQ ID NOs: 9, 10 and 11, respectively; and the sequences of the anti-PD1 antibody light chain LCDR1, LCDR2 and LCDR3 are shown in SEQ ID NOs: 12, 13 and 14, respectively.

2. The pharmaceutical composition according to claim 1, wherein The heavy chain variable region sequence of the anti-CTLA4 antibody is shown in SEQ ID NO: 7, the light chain variable region sequence of the anti-CTLA4 antibody is shown in SEQ ID NO: 8, the heavy chain variable region sequence of the anti-PD1 antibody is shown in SEQ ID NO: 15, and the light chain variable region sequence of the anti-PD1 antibody is shown in SEQ ID NO:

16.

3. The pharmaceutical composition according to claim 1, wherein The heavy chain sequence of the anti-CTLA4 antibody is shown in SEQ ID NO: 17, the light chain sequence of the anti-CTLA4 antibody is shown in SEQ ID NO: 18, the heavy chain sequence of the anti-PD1 antibody is shown in SEQ ID NO: 19, and the light chain sequence of the anti-PD1 antibody is shown in SEQ ID NO:

20.

4. The pharmaceutical composition according to any one of claims 1 to 3, wherein the small cell lung cancer is extensive-stage small cell lung cancer.

5. The pharmaceutical composition according to claim 4, wherein the chemotherapy drugs are carboplatin / cisplatin and etoposide.

6. The pharmaceutical composition according to claim 5, wherein during the treatment period, the mixed antibody is administered at a dosage of 5 mg / kg, once every three weeks, by intravenous infusion on day 1, with a cycle of 21 days.

7. The pharmaceutical composition according to claim 5, wherein during the treatment period: the dose of carboplatin is a target AUC of 5 mg / min / mL, or the dose of cisplatin is 75 mg / min / mL. 2 , administered by intravenous infusion on day 1; etoposide dose was 100 mg / m 2 , administered by intravenous infusion on days 1, 2, and 3, with a cycle of 21 days.

8. The pharmaceutical composition according to claim 6 or 7, wherein after 4-6 treatment periods, the mixed antibody maintenance treatment is continued, and the mixed antibody is administered at a dose of 5 mg / kg, administered by intravenous infusion on day 1, and administered once every three weeks until disease progression.

9. A method for treating small cell lung cancer, comprising administering to a subject a pharmaceutical composition comprising an effective amount of a mixed antibody of anti-CTLA4 and anti-PD1 and a chemotherapeutic drug, wherein the mixed antibody is produced by a single host cell containing nucleic acids encoding two different antibodies, anti-CTLA4 and anti-PD1, wherein: The sequences of the anti-CTLA4 antibody heavy chain HCDR1, HCDR2 and HCDR3 are shown in SEQ ID NOs: 1, 2 and 3, respectively; the sequences of the anti-CTLA4 antibody light chain LCDR1, LCDR2 and LCDR3 are shown in SEQ ID NOs: 4, 5 and 6, respectively; the sequences of the anti-PD1 antibody heavy chain HCDR1, HCDR2 and HCDR3 are shown in SEQ ID NOs: 9, 10 and 11, respectively; and the sequences of the anti-PD1 antibody light chain LCDR1, LCDR2 and LCDR3 are shown in SEQ ID NOs: 12, 13 and 14, respectively.

10. The method of claim 9, wherein: The heavy chain variable region sequence of the anti-CTLA4 antibody is shown in SEQ ID NO: 7, the light chain variable region sequence of the anti-CTLA4 antibody is shown in SEQ ID NO: 8, the heavy chain variable region sequence of the anti-PD1 antibody is shown in SEQ ID NO: 15, and the light chain variable region sequence of the anti-PD1 antibody is shown in SEQ ID NO:

16.

11. The method of claim 9, wherein: The heavy chain sequence of the anti-CTLA4 antibody is shown in SEQ ID NO: 17, the light chain sequence of the anti-CTLA4 antibody is shown in SEQ ID NO: 18, the heavy chain sequence of the anti-PD1 antibody is shown in SEQ ID NO: 19, and the light chain sequence of the anti-PD1 antibody is shown in SEQ ID NO:

20.

12. The method according to any one of claims 9 to 11, wherein the small cell lung cancer is extensive-stage small cell lung cancer.

13. The method of claim 12, wherein the chemotherapy drugs are carboplatin / cisplatin and etoposide.

14. The method according to claim 13, wherein during the treatment period, the mixed antibody is administered at a dose of 5 mg / kg, once every three weeks, by intravenous infusion on day 1, with a cycle of 21 days.

15. The method of claim 13, wherein during the treatment period: the carboplatin dose is a target AUC of 5 mg / min / mL, or the cisplatin dose is 75 mg / m 2 , administered by intravenous infusion on day 1; etoposide dose was 100 mg / m 2 , administered by intravenous infusion on days 1, 2, and 3, with a cycle of 21 days.

16. The method according to claim 14 or 15, wherein after 4-6 treatment periods, the mixed antibody maintenance treatment is continued, and the mixed antibody is administered at a dose of 5 mg / kg, administered by intravenous infusion on day 1, and administered once every three weeks until disease progression.

17. A pharmaceutical composition for treating extensive-stage small cell lung cancer, comprising an effective amount of a mixed antibody of anti-CTLA4 and anti-PD1, wherein the mixed antibody is produced by a single host cell containing nucleic acids encoding two different antibodies, anti-CTLA4 and anti-PD1, wherein: The heavy chain sequence of the anti-CTLA4 antibody is shown in SEQ ID NO: 17, the light chain sequence of the anti-CTLA4 antibody is shown in SEQ ID NO: 18, the heavy chain sequence of the anti-PD1 antibody is shown in SEQ ID NO: 19, and the light chain sequence of the anti-PD1 antibody is shown in SEQ ID NO: 20.