FDA has approved luspatercept-aamt (Reblozyl, sponsored by Celgene Corp) for the treatment of anemia failing an erythropoiesis stimulating agent and requiring 2 or more red blood cell units over 8 weeks in adult patients with very low- to intermediate-risk myelodysplastic syndromes with ring sideroblasts or with myelodysplastic/myeloproliferative neoplasm with ring sideroblasts and thrombocytosis.
Efficacy was demonstrated in the MEDALIST trial (NCT02631070), a randomized, multi-center, double-blind, placebo-controlled trial in 229 patients with IPSS-R very low, low, or intermediate-risk myelodysplastic syndromes who had ring sideroblasts and required RBC transfusions (2 or more RBC units over 8 weeks). Patients were randomized 2:1 to luspatercept-aamt or placebo. All patients received best supportive care, which included RBC transfusions.
The main efficacy endpoint in MDS-RS and MDS-RS-T was the proportion of patients who were RBC-transfusion independent, defined as the absence of any RBC transfusion during any consecutive 8-week period between Weeks 1 and 24.
Of the 153 patients who received luspatercept-aamt, 58 (37.9%, 95% CI: 30.2, 46.1) were RBC-TI for at least 8 weeks, compared to 10 patients (13.2%, 95% CI: 6.5, 22.9) who received placebo (treatment difference 24.6% (95% CI: 14.5, 34.6; p<0.0001.)
