Keymed Biosciences Reports CM313 Results for Immune Thrombocytopenia in NEJM

In CHENGDU, China, on June 20, 2024, Keymed Biosciences Inc. (HKEX: 02162) revealed that a research team led by Lei Zhang and Renchi Yang from the Institute of Hematology, Chinese Academy of Medical Sciences, recently published their findings on a new treatment for Immune Thrombocytopenia (ITP) in the New England Journal of Medicine. The study, titled "A Novel Anti-CD38 Monoclonal Antibody for Treating Immune Thrombocytopenia," explored the safety and initial effectiveness of CM313 in adult patients with primary ITP.

The investigation was a phase I/II, single-arm, open-label study that enrolled 22 participants. One participant dropped out after the first infusion, leaving 21 patients who completed both the 8-week treatment and the subsequent 16-week follow-up. The study's results were promising: 95.5% of the participants (21 out of 22) achieved a platelet count of 50 × 10^9/L or higher during the 8-week treatment period. The median duration of this response was 23 weeks, with an interquartile range of 17 to 24 weeks. Remarkably, the median time to reach a platelet count of 50 × 10^9/L was one week, with a range between one to three weeks. Additionally, the time to achieve a platelet count of 30 × 10^9/L with at least a two-fold increase from baseline was also one week.

Long-term results demonstrated that 63.6% of the patients (14 out of 22) maintained a durable platelet count response, defined as achieving a platelet count of 50 × 10^9/L or higher at least six times out of the last eight measurements. Throughout the study, an overall response, either complete or partial, was seen in 21 patients, with 20 achieving a complete response. There was a significant reduction in the proportion of patients experiencing bleeding, dropping from 68.2% at baseline to just 4.8% at week eight. Most participants were able to stop taking additional medications as their platelet counts returned to normal or safe levels due to the CM313 treatment. The study concluded that CM313 demonstrated rapid and sustained efficacy in 95.5% of ITP patients who had previously undergone multiple therapies, and it was well-tolerated among the participants.

CM313, a humanized monoclonal antibody targeting CD38, is the first domestically-developed anti-CD38 antibody to receive IND approval by the NMPA in China. Previous studies have shown its favorable safety profile and promising efficacy in patients with relapsed/refractory multiple myeloma (RRMM) and primary ITP. Furthermore, CM313 is currently being evaluated for its potential use in treating systemic lupus erythematosus (SLE).

Keymed Biosciences Inc. is dedicated to addressing urgent unmet clinical needs by providing innovative, high-quality, and affordable therapies to patients both in China and internationally. The company has built a fully integrated platform for biological drug development covering all key functions, from target validation to clinical development and manufacturing. This comprehensive approach has enabled Keymed to quickly and efficiently identify, develop, and advance a diverse pipeline of antibody-based therapies, including monoclonal antibodies, antibody-drug conjugates (ADCs), and bispecific antibodies.