HUTCHMED (NASDAQ:HCM) shares gained 2.4% in premarket trading on Friday after the company unveiled encouraging Phase III clinical trial results for sovleplenib in patients with warm antibody autoimmune hemolytic anemia (wAIHA) at the European Hematology Association (EHA) Congress.
The findings were presented on Thursday at the EHA meeting in Stockholm, Sweden, and were selected for inclusion in the organisation’s official press programme.
Phase III Study Achieves Primary Endpoint
The Phase III ESLIM-02 trial successfully met its primary endpoint, with sovleplenib delivering a durable response rate of 66% between weeks five and 24 of treatment, compared with 15% for patients receiving placebo.
The study enrolled 90 patients in China who had relapsed or were refractory to at least one prior standard treatment for warm antibody autoimmune hemolytic anemia.
Strong Improvements Across Multiple Clinical Measures
Beyond the primary endpoint, sovleplenib demonstrated notable benefits across several secondary efficacy measures.
The overall response rate reached 70% in the treatment arm, significantly higher than the 22% reported in the placebo group.
Patients receiving sovleplenib were also less likely to require rescue therapy, with usage falling to 16% compared with 54% among placebo-treated patients.
Similarly, only 11% of patients in the sovleplenib group required red blood cell transfusions, versus 43% in the placebo arm.
Faster and More Durable Responses Observed
The treatment also produced faster clinical responses.
Median time to response was 3.1 weeks for patients receiving sovleplenib, compared with 6.3 weeks for those receiving placebo.
Among patients who responded to treatment, the median cumulative duration of response reached 16.1 weeks, substantially longer than the 6.1 weeks recorded in the placebo group.
Regulatory Momentum Builds in China
HUTCHMED continues to make regulatory progress with sovleplenib in China.
In April, the China National Medical Products Administration (NMPA) accepted the company’s New Drug Application for review and granted the treatment priority review status.
The application covers adult patients with warm antibody autoimmune hemolytic anemia who have shown an insufficient response to at least one prior glucocorticoid therapy.
Earlier, in March, the NMPA awarded sovleplenib Breakthrough Therapy Designation for the same indication, highlighting the drug’s potential to address a significant unmet medical need.
Safety Profile Remains Favorable
The study also produced encouraging safety data.
Grade 3 or higher treatment-emergent adverse events were reported in 43% of patients treated with sovleplenib, compared with 59% of those receiving placebo.
Importantly, no treatment-related deaths were reported during the trial, and no patients discontinued treatment due to treatment-related adverse events in the sovleplenib arm.
The positive efficacy and safety results strengthen HUTCHMED’s case for regulatory approval and position sovleplenib as a potential new treatment option for patients with warm antibody autoimmune hemolytic anemia who have limited alternatives after standard therapies fail.