CAMBRIDGE, MA, USA I April 30, 2015 I Acceleron Pharma Inc. (NASDAQ:XLRN), a clinical stage biopharmaceutical company focused on the discovery, development and commercialization of novel therapeutic candidates that regulate cellular growth and repair, today announced that Acceleron and its collaboration partner, Celgene Corporation, plan to initiate a Phase 3 program with luspatercept in myelodysplastic syndromes and beta-thalassemia by year-end 2015. The companies will continue to develop sotatercept for patients with chronic kidney disease.

Preliminary data from the ongoing phase 2 clinical trial of luspatercept in patients with lower risk MDS will be presented by Uwe Platzbecker, M.D., University Hospital in Dresden, Germany, in the oral session “Best of Clinical Trials II” at the MDS Foundation 13th International Symposium on Myelodysplastic Syndromes on Saturday May 2, 2015, at 10:30 AM (EDT) at the Washington Marriott Wardman Park Hotel in Washington, D.C.

About Luspatercept

Luspatercept is a modified activin receptor type IIB fusion protein that acts as a ligand trap for members in the Transforming Growth Factor-Beta (TGF-β) superfamily involved in the late stages of erythropoiesis (red blood cell production). Luspatercept regulates late-stage erythrocyte (red blood cell) precursor cell differentiation and maturation. This mechanism of action is distinct from that of erythropoietin (EPO), which stimulates the proliferation of early-stage erythrocyte precursor cells. Acceleron and Celgene are jointly developing luspatercept as part of a global collaboration. Luspatercept is currently in phase 2 clinical trials in patients with beta-thalassemia and in patients with myelodysplastic syndromes. For more information, please visit www.clinicaltrials.gov.

About Myelodysplastic Syndromes

MDS are a heterogeneous group of hematologic malignancies of the bone marrow commonly leading to severe and chronic anemia due to ineffective erythropoiesis. The National Cancer Institute estimates that more than 10,000 people are diagnosed with MDS in the United States each year. Patients with MDS have a hypercellular bone marrow with various dysplastic changes of the cells that are also seen in peripheral blood, resulting in cytopenias (low blood cell counts) and an increased risk of progression to acute myeloid leukemia. Nearly all MDS patients suffer from anemia. The anemia in MDS is characterized by high endogenous levels of EPO driving an abundance of early stage red blood cell precursors and an inability of these precursor cells to properly differentiate into healthy, functional red blood cells. Many patients are therefore unresponsive to the administration of erythropoietin to correct the resulting anemia and instead require red blood cell transfusions, which can increase the risk of infection and iron-overload related toxicities.

About Acceleron

Acceleron is a clinical stage biopharmaceutical company focused on the discovery, development and commercialization of novel therapeutic candidates that regulate cellular growth and repair. The company is a leader in understanding the biology of the TGF-β protein superfamily, a large and diverse group of molecules that are key regulators in the growth and repair of tissues throughout the human body, and in targeting these pathways to develop important new medicines. Acceleron has built a highly productive R&D platform that has generated innovative clinical and preclinical protein therapeutic candidates with novel mechanisms of action. These therapeutic candidates have the potential to significantly improve clinical outcomes for patients with cancer and rare diseases.

SOURCE: Acceleron