China-based Hutchison China Meditech (HutchMed; NASDAQ: HCM, HKG: 0013) has announced the initiation of a Phase II/III study for its sovleplenib (HMPL-523) in adult patients with warm antibody autoimmune hemolytic anemia (wAIHA) in China. The first patient was dosed on September 30. This marks a significant step forward in the development of innovative treatments for this rare autoimmune disorder.
Sovleplenib: Drug Profile and Mechanism
Sovleplenib is a novel, investigational, selective small molecule inhibitor for oral administration targeting the spleen tyrosine kinase (Syk). Syk is a major component in B-cell receptor and Fc receptor signaling and is an established target for the treatment of multiple subtypes of B-cell lymphomas and autoimmune disorders. HutchMed owns all global rights to the drug.
Disease Background
AIHA is an autoimmune disorder characterized by the destruction of red blood cells (RBCs) due to the production of antibodies against RBCs. The incidence of AIHA is estimated to be 0.8-3.0/100,000 adults per year, with an estimated prevalence of 17 per 100,000 adults and a death rate of 8-11%. wAIHA is the most common of the autoimmune hemolytic diseases, accounting for about 75-80% of all adult AIHA cases.
Clinical Trial Design
The trial is a randomized, double-blind, placebo-controlled study. The Phase II stage will evaluate the safety and preliminary efficacy of sovleplenib in adult patients with wAIHA. If the results of the Phase II stage are positive, the Phase III stage will be initiated to confirm such efficacy and safety. The primary endpoint for the Phase II study is the proportion of patients with overall hemoglobin (Hb) response by Week 24, while the primary endpoint for the Phase III study would be the proportion of patients who achieve a durable Hb response by Week 24. Approximately 110 patients are expected to be enrolled.
Future Outlook
The initiation of the Phase II/III study for sovleplenib underscores HutchMed’s commitment to advancing innovative treatments for rare autoimmune disorders. By targeting Syk, sovleplenib aims to address significant unmet medical needs and improve patient outcomes in wAIHA.-Fineline Info & Tech
