Bristol Myers Squibb has announced positive top-line results from an ongoing ex-US Phase II registrational study evaluating Reblozyl (luspatercept-aamt) in adults with alpha-thalassemia–related anaemia.

The trial met its primary endpoints in both Non-Transfusion-Dependent (NTD) and Transfusion-Dependent (TD) patient cohorts. In NTD patients, Reblozyl demonstrated a statistically significant and clinically meaningful increase in haemoglobin levels compared with placebo. In the TD cohort, the therapy achieved a statistically significant and clinically meaningful reduction in Red Blood Cell (RBC) transfusion burden.

The study also met all key secondary endpoints and the safety profile of Reblozyl was consistent with its established safety data in thalassemia.

Cristian Massacesi, Executive Vice President, Chief Medical Officer and Head of Development at Bristol Myers Squibb, said the findings further support the medicine’s global potential. He noted that the study is the first registrational Phase II trial specifically designed to address the needs of patients with alpha-thalassemia, particularly in China, where treatment options remain limited for this lifelong and potentially serious condition.

The data will be presented at an upcoming medical congress and discussed with China’s Centre for Drug Evaluation.

The Phase II study is assessing the efficacy and safety of luspatercept in combination with best supportive care versus placebo in adults and adolescents with alpha-thalassemia. For the NTD cohort, the primary endpoint measured an increase of at least 1 g/dL in mean haemoglobin levels over a continuous 12-week period without RBC transfusion. For the TD cohort, the primary endpoint assessed a 50 percent or greater reduction in RBC transfusion burden, with a minimum reduction of two units over any continuous 12-week interval. Adolescent cohorts in both groups are ongoing.

Reblozyl, a first-in-class erythroid maturation agent, promotes late-stage red blood cell maturation. The therapy is being developed and commercialised globally in collaboration with Merck since November 2021.

In the United States, Reblozyl is approved for the treatment of anaemia in adult patients with beta-thalassemia requiring regular RBC transfusions, as well as certain lower-risk Myelodysplastic Syndromes (MDS). It is not indicated as a substitute for immediate RBC transfusions or for patients with non-transfusion-dependent beta-thalassemia in the US.