Acceleron releases luspatercept MDS results

Acceleron Pharma Inc. (NASDAQ:XLRN) announced preliminary results from a 44-patient, open-label Phase II dose-escalation trial of luspatercept ( ACE-536) to treat lower risk myelodysplastic syndromes (MDS).

In a high-dose group receiving 0.75-1.75 mg/kg every three weeks, 22 (63%) of 35 patients met the primary efficacy endpoint of a hemoglobin increase of ≥1.5 g/dL for ≥2 weeks or a reduction of ≥4 units or ≥50% reduction in transfusions over 8 weeks. In a low-dose group receiving 0.125-0.5 mg/kg, 3 (33%) of 9 patients met the same endpoint. The high-dose group also had a 54% response rate in achieving the International Working Group (IWG) hematologic improvement-erythroid (HI-E) threshold of efficacy, compared to 22% in the low-dose group. Acceleron reported two serious adverse events "possibly related" to treatment: grade 3 muscle pain and grade 3 worsening of general condition. ...