An Open, Exploratory Clinical Study of CM336 in the Treatment of Immune Thrombocytopenia

Inclusion Criteria:

• Age 18 and above, male or female;

• Conform to the diagnostic criteria of persistent or chronic immune thrombocytopenia (ITP);

• Failure of previous glucocorticoid therapy;

• In the second-line treatment phase, eligible subjects must meet any of the followingcriteria: (1) Demonstrate no response to treatment with at least one thrombopoietinreceptor agonist (including but not limited to recombinant human thrombopoietin [rhTPO], eltrombopag, hetrombopag, avatrombopag, or romiplostim); Fail to achievesustained response (manifested as non-response, loss of response, or diseaserelapse) following anti-CD20 monoclonal antibody therapy (e.g., rituximab) oranti-CD38 monoclonal antibody therapy; (2) Exhibit no therapeutic response orexperience disease relapse after splenectomy.

• The platelet count was <30×109/L within 48 hours before the first administration;

• ECOG physical state score ≤ 2 points;

• Patients receiving maintenance treatment (including corticosteroids (less than orequal to 20mg prednisone), TPO receptor agonists, etc.) must have a stable dose atleast 4 weeks before the first administration;

• Signed and dated written informed consent;

Exclusion Criteria:

• Received any treatment of anti-BCMA antibody drug;

• Accompanied by autoimmune hemolytic anemia, or various secondary and hereditarythrombocytopenia;

• History of any thrombotic or embolic events in the 12 months prior to the first doseor accompanied by extensive and severe bleeding, such as hemoptysis, uppergastrointestinal hemorrhage, intracranial hemorrhage, etc;

• Participated in any other study drug or exposure to other study drugs within 4 weeksor 5 half-lives before the first dose (whichever is longer);

• Use of anticoagulants or any drug with antiplatelet effects (such as aspirin) within 3 weeks before the first dose;

• Treatment with ITP (methylprednisolone, platelet, gamma-globulin infusion or TPOreceptor agonist therapy) within 2 weeks before the first dose;

• Splenectomy was performed within 6 months before the first dose;

• Patients who received azathioprine, danazol, cyclosporine A, tacrolimus, sirolimus,etc., within 4 weeks prior to the first dose; or received treatments such as CD20monoclonal antibodies (e.g., rituximab), CD38 monoclonal antibodies,cyclophosphamide, or vindesine within 3 months prior to the first dose；

• Received a live vaccine within 4 weeks before the first dose, or planned to receiveany live vaccine during the clinical trial;

• Those who have received allogeneic stem cell transplantation or organtransplantation in the past;

• Other serious diseases that may limit the subject's participation in this trial (such as diabetes; Hepatic and renal insufficiency; Severe cardiac insufficiency;Myocardial obstruction or unstable arrhythmia or unstable angina pectoris in recent 6 months; Gastric ulcer, etc.);

• Patients with malignant tumors within 5 years before the screening;

• A history of severe recurrent or chronic infection;

• A known or suspected history of immunosuppression, including a history of invasiveopportunistic infections;

• Clinically significant laboratory abnormalities at the time of screening;

• HIV antibody or syphilis antibody positive;

• Accompanied by uncontrollable active infection, including hepatitis B, hepatitis C;Pregnant women, suspected pregnancies (positive pregnancy test for human chorionicgonadotropin in urine at screening) and lactating patients;

• Patients with mental disorders who cannot normally obtain informed consent andconduct trials and follow-up;

• Patients whose symptoms of toxicity from pre-trial treatment have not resolved;

• Any other ineligibility for subjects in the study was assessed by the investigator.