Acceleron Pharma Inc. announced that the journal Blood has published results from the Phase 2 study of luspatercept in patients with red blood cell (RBC) transfusion-dependent and non-transfusion-dependent beta-thalassemia. Luspatercept is an investigational therapy that is part of a global collaboration between Acceleron and Celgene. In this open-label, Phase 2 study (a three-month initial stage followed by a five-year extension stage), patients were treated with luspatercept subcutaneously once every three weeks. The primary outcome measures were a reduction in RBC transfusion burden—compared with pretreatment—in transfusion-dependent patients, and changes in hemoglobin levels from baseline in non-transfusion-dependent patients. The extension study is ongoing and evaluates the long-term safety and tolerability of luspatercept for up to 5 years. Luspatercept is being evaluated in ongoing studies in patients with non-transfusion-dependent beta-thalassemia (the Phase 2 BEYOND trial) as well as in patients with lower-risk myelodysplastic syndromes (MDS) (the Phase 2 PACE-MDS trial and the Phase 3 MEDALIST and COMMANDS trials) and in a Phase 2 trial in patients with myelofibrosis. Luspatercept is an investigational therapy that is not approved for any use in any country. Celgene and Acceleron are planning submission of marketing applications for luspatercept in the United States and Europe in the first half of 2019.