Safety of Luspatercept in Pediatric Beta-Thalassemia Comparable With Adults

A phase IIA study is currently underway to evaluate safety and dosing for luspatercept in both transfusion-dependent (TD) and nondependent pediatric β-thalassemia. Investigators presented data from this ongoing study at the European Hematology Association (EHA) 2024 Hybrid Congress in Madrid and reported that the safety profile for this agent in pediatric patients with TD disease is comparable with the safety profile in adult patients.

Lead study author Antonis Kattamis, MD, of National and Kapodistrian University in Athens, Greece, wrote of “an unmet need among pediatric [patients] with β-thalassemia for treatments that reduce anemia, minimize chronic [red blood cell] transfusions, and mitigate secondary iron overload.” He then highlighted that luspatercept has shown benefit in adults with either TD or nondependent disease.

At EHA 2024, the investigators reported safety data from the first part of the two-part study, specifically regarding patients with TD β-thalassemia who were younger than 18 but no younger than 12 years of age. These data were from 12 patients who had received at least four transfusions in the 24 weeks pre-enrollment.

The 12 patients were divided into two cohorts of six patients each. Both cohorts received subcutaneous luspatercept, one at 0.75 mg/kg (cohort 1) and the other at 1.0 mg/kg (cohort 2) every three weeks for up to four cycles. The median treatment duration was 651.5 days in cohort 1 and 219.0 days in cohort 2, and patients received a median of 31.0 and 10.5 doses, respectively. Both cohorts—four patients in cohort 1 and one in cohort 2— had dose titrations of up to 1.25 mg/kg.

Regarding safety results, all 12 patients reported treatment-emergent adverse events (TEAEs), and TEAEs related to luspatercept were experienced by two patients in cohort 1 and four in cohort 2. However, no patients in either cohort experienced grade 3 or 4 TEAEs related to the agent, and there were no TEAEs that led to treatment discontinuation. There were also no dose-limiting toxicities reported by either cohort.

Reference

Kattamis A, Musallam KM, Perrotta S, et al. Safety data from the dose-finding cohorts: a phase 2A study of luspatercept in pediatric patients with beta-thalassemia. Abstract P1516. Presented at the European Hematology Association 2024 Hybrid Congress; June 13-16, 2024; Madrid, Spain.