A new phase 2 clinical trial testing an experimental antihuman CD38 monoclonal antibody for the treatment of immune thrombocytopenia (ITP) is now open.

The prospective, 1-arm, open trial will assess the safety and efficacy of the experimental treatment called CM313 in an estimated 20 patients, who are at least 18 years of age and who have not responded adequately or relapsed after first-line treatment and at least 1 second-line therapy including rituximab and/or a thrombopoietin receptor agonist.

Read more about experimental therapies for ITP

During the trial, participants will receive intravenous CM313 once a week for 8 weeks. 

The primary outcome measure will be the proportion of patients with a platelet count of 50 × 109/L or more at week 8 without rescue therapy or a dose increment of thrombopoietin receptor agonist or corticosteroids during the study period. Another primary outcome measure will be safety as measured by the incidence, severity, and relationship of treatment-emergent adverse events following treatment.

Secondary outcome measures include the response rate of the treatment, the duration from the start of treatment to achieving a platelet count of at least 50×109/L, the number of patients with clinically significant bleeding, and the levels of autoantibodies against platelet glycoprotein.

The trial will take place at the Chinese Academy of Medical Science and Blood Disease Hospital in Tianjin, China, but is not yet recruiting participants. The estimated completion date of the trial is December 30, 2024.

Patients who have received any treatment with antiCD38 antibody drugs in the past are not eligible to participate in the trial. 

CM313 is a new type of monoclonal antibody targeting CD38. Research has shown that it also has good therapeutic effects in multiple myeloma.

ITP is an autoimmune disease characterized by low platelet count and skin and mucosal bleeding.


A prospective, one-arm and open clinical study of CM313 in the treatment of immune thrombocytopenia (2022-CM313-ITP). US National Library of Medicine. Updated January 23, 2023. Accessed January 27, 2023.