Sotatercept slowed progression of vascular calcification and improved abnormal changes in bone mineral density

Sotatercept produced dose dependent increases in hemoglobin

CAMBRIDGE, MA, USA I November 13, 2014 I Acceleron Pharma Inc. (NASDAQ:XLRN), a clinical stage biopharmaceutical company focused on the discovery, development and commercialization of novel protein therapeutics for cancer and rare diseases, today reported that investigators on the sotatercept program presented interim clinical data demonstrating encouraging effects of sotatercept on vascular calcification, bone mineral density, and hemoglobin levels in patients with end-stage renal disease on hemodialysis. The data were presented at the American Society of Nephrology (ASN) Kidney Week 2014 meeting in Philadelphia, PA. Acceleron’s collaboration partner, Celgene, is conducting the phase 2 clinical trial of sotatercept in patients with end-stage renal disease on hemodialysis.

“The sotatercept data showing a reduction in the rate of vascular calcification suggests a novel potential treatment for patients with end-stage renal disease,” said Matthew L. Sherman, M.D., Chief Medical Officer of Acceleron. “Cardiovascular disease is the leading cause of death in these ESRD patients on hemodialysis and we’re encouraged by the potential of sotatercept to help address this unmet need.”

Vascular Calcification:

Many patients on hemodialysis suffer from rapidly increasing vascular calcification which can lead to serious and often fatal cardiovascular disease. Sotatercept slowed progression of vascular calcification in the abdominal aorta.

  • Dose dependent change from baseline in total Agatston score over approximately 8 months was 58.4%, 24.9%, 17.3% and 3.4% in the placebo, 0.3, 0.5 and 0.7 mg/kg cohorts, respectively.

Renal Osteodystrophy

Hemodialysis patients also suffer from renal osteodystrophy with aberrant bone metabolism characterized by increases in trabecular and decreases in cortical bone mineral density leading to increased risk of fractures. Sotatercept treatment led to decreases in trabecular and increases in cortical bone mineral density over approximately 8 months.

  • Dose dependent decreases in trabecular bone mineral density
    • Changes in the lumbar spine bone mineral density were 12.6%, 8.0%, 0.5% and -2.7% in the placebo, 0.3, 0.5 and 0.7 mg/kg cohorts, respectively.
  • Dose dependent increases in cortical bone mineral density
    • Changes in the femoral neck cortical bone mineral density were -0.9%, -1.4%, 1.6% and 3.0% in the placebo, 0.3, 0.5 and 0.7 mg/kg cohorts, respectively.
    • Changes in the total hip cortical bone mineral density were -0.1%, -1.1%, 0.5% and 2.7% in the placebo, 0.3, 0.5 and 0.7 mg/kg cohorts, respectively.

Anemia

Sotatercept also produced dose dependent increases in hemoglobin in these patients on hemodialysis during the first 28-day dose cycle.

  • A hemoglobin increase of ≥1.0 g/dL was achieved by 13%, 38%, 43% and 60% of the patients in the placebo, 0.3, 0.5 and 0.7 mg/kg cohorts, respectively.
  • Treatment with EPO for hemoglobin levels below 9 g/dL was given to 63%, 25%, 29% and 0% of the patients in the placebo, 0.3, 0.5 and 0.7 mg/kg cohorts, respectively.

Sotatercept was generally well-tolerated and most treatment emergent adverse events were mild or moderate in severity, unrelated to study drug, relatively similar between groups, and generally consistent with subjects’ medical histories. The most common treatment emergent adverse events were fatigue, pain, constipation, nausea, viral infection, hypertension, fall, dizziness and increased blood phosphorus.

The clinical posters containing these and other data are available on Acceleron’s website (www.acceleronpharma.com) in the “Publications” tab.

About Sotatercept

Sotatercept is an activin receptor type IIA 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). Sotatercept 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 sotatercept as part of a global collaboration. Sotatercept is currently in multiple phase 2 clinical trials. For more information, please visit www.clinicaltrials.gov.

About Acceleron

Acceleron is a clinical stage biopharmaceutical company focused on the discovery, development and commercialization of novel protein therapeutics for cancer and rare diseases. The company is a leader in understanding the biology of the Transforming Growth Factor-Beta (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 protein therapeutic candidates have the potential to significantly improve clinical outcomes for patients with cancer and rare diseases.

SOURCE: Acceleron