Biopharmaceutical company Acceleron Pharma has commenced a Phase II study to evaluate the safety, tolerability and efficacy of ACE-536 in patients with low-risk or intermediate-1 risk myelodysplastic syndromes (MDS).

ACE-536 is a modified type II activin receptor fusion protein that promotes late-stage erythrocyte precursor cell differentiation, distinct from erythropoietin, which acts during early, proliferative stages of erythropoiesis.

Universitatsklinikum Carl Gustav Carus, Dresden, haematology / oncology outpatient department director and ACE-536 PACE-MDS Phase II study coordinating principal investigator professor Dr Uwe Platzbecker said; "The anemia experienced by patients with MDS is clinically challenging because it is often unresponsive to administration of erythropoietin and many patients ultimately require red blood cell transfusions."

Efficacy measures of the Phase II trial include increase in haemoglobin levels, reduction of red blood cell transfusion burden, and other hematologic parameters, in addition to biomarkers of iron and bone metabolism.

"ACE-536 is a modified type II activin receptor fusion protein that promotes late-stage erythrocyte precursor cell differentiation, distinct from erythropoietin, which acts during early, proliferative stages of erythropoiesis."

ACE-536 produced a dose-dependent increase in red blood cells and haemoglobin levels in a Phase I study conducted in healthy volunteers.

Acceleron chief medical officer Dr Matthew Sherman said ACE-536 is a potent therapy for anemia in MDS.

"Unlike erythropoietin, ACE-536 may target the specific defect in the erythropoietic maturation process in MDS patients and we are optimistic that it could become an important new therapeutic option for this underserved patient population," Sherman said.

Acceleron, which is developing ACE-536 in a global collaboration with Celgene, has earned a $10m milestone payment for the commencement of the study

Under the deal signed between both the companies, Acceleron is eligible for development, regulatory and commercial milestones totalling $200m for the ACE-536 programme.