A Novel Approach to Treating Refractory Immune Thrombocytopenia

CM313 is a novel (non–FDA-approved) anti-CD38 monoclonal antibody designed to deplete plasma cells and other immune cells involved in the pathogenesis of immune thrombocytopenic purpura (ITP). This phase 1/2, open-label study from China evaluated safety and efficacy of intravenous CM313 (16 mg/kg weekly for 8 weeks) in 22 adult patients with primary ITP refractory to at least one prior therapy (platelet count, <30 x 10⁹/L). Concomitant ITP therapies, including steroids, were allowed, and posttreatment follow-up lasted 16 weeks.

CM313 was generally well-tolerated, with infusion-related reactions being the most common adverse events, occurring in seven patients. Regarding efficacy, 21 patients achieved the desired platelet response (≥2 consecu…