The use of luspatercept for thalassemia in adults

Luspatercept is an activin receptor ligand trap that has been shown to enhance late-stage erythropoiesis in animal models of beta-thalassemia. A multicenter, international, phase 2 dose-finding study was initiated in adult patients with beta-thalassemia, either non-transfusion-dependent thalassemia (NTDT) or transfusion-dependent thalassemia (TDT). Positive results of the phase 2 study paved the way to a randomized phase 3 clinical trial (BELIEVE) to assess the efficacy and safety of luspatercept. The BELIEVE trial is a randomized, double-blind, placebo-controlled phase 3 trial. Three hundred thirty-six patients aged >= 18 years with TDT (regularly transfused, 6-20 red blood cell units within 24 weeks before randomization) were included in the trial. Patients received luspatercept or placebo subcutaneously every 21 days for >= 48weeks and best supportive care. Forty-eight of 224 patients (21.4%) in the luspatercept group achieved the primary end points (>= 33% reduction in transfusion burden) compared with those in the placebo group (4.5%; P < .001). Moreover, more patients had a >= 33% reduction in transfusion burden during any rolling 12-week interval (70.5% vs 29.5%) or any 24-week interval (41.1% vs 2.7%) with luspatercept than with the placebo. Transfusion independence was achieved by 11% of patients in the luspatercept group. Transient adverse events were more frequent with luspatercept than with placebo, but were manageable. Luspatercept was approved by the US Food and Drug Administration in 2019 and by the European Medicines Agency in 2020. The luspatercept trial is registered onwww.clinicaltrials.gov at #NCT01749540 and the BELIEVE trial at #NCT02604433.

Automated summary

Luspatercept, an activin receptor ligand trap, has shown efficacy in enhancing late-stage erythropoiesis in patients with beta-thalassemia, leading to significant reduction in transfusion burden and even achieving transfusion independence in some cases. This drug has been approved by regulatory agencies in the US and Europe after positive results from phase 2 and phase 3 trials.