(HealthDay)—For patients with transfusion-dependent β-thalassemia, significantly more have a reduction in transfusion burden with receipt of luspatercept versus placebo, according to a study published in the March 26 issue of the New England Journal of Medicine.

M. Domenica Cappellini, M.D., from the University of Milan, and colleagues randomly assigned adults with transfusion-dependent β-thalassemia to receive either best supportive care plus luspatercept (224 patients) or (112 patients) for at least 48 weeks in a phase 3 trial. In both groups, luspatercept or placebo was administered for a median of about 64 weeks.

The researchers found that compared with the placebo group, in the luspatercept group, a significantly higher percentage of patients had a reduction in transfusion burden of at least 33 percent from baseline during weeks 13 through 24 plus a reduction of at least two red-cell units during this 12-week interval (21.4 versus 4.5 percent). The percentage of who had a reduction in transfusion burden of at least 33 percent was greater in the luspatercept versus during any 12-week interval (70.5 versus 29.5 percent), as was the percentage with a reduction of at least 50 percent (40.2 versus 6.3 percent).

"A five-year open-label extension phase is under way to provide long-term data on the safety of luspatercept and its effects on the transfusion burden and iron outcomes," the authors write.

Several authors disclosed to , including Celgene, the manufacturer of luspatercept, which funded the study in collaboration with Acceleron Pharma.