Patient-Reported Outcomes With Luspatercept Through 5 Years of Treatment in Patients With Non-Transfusion-Dependent β-Thalassemia Treated in the BEYOND Trial.

In the phase 2, double-blind, randomized controlled BEYOND trial (NCT03342404), luspatercept increased hemoglobin levels in patients with non-transfusion-dependent β-thalassemia (NTDT). This study assessed long-term effects of luspatercept on patient-reported outcomes (PROs), using data from BEYOND and patients who continued luspatercept treatment in the phase 3b long-term follow-up (LTFU) study (NCT04064060). In BEYOND, patients received luspatercept or placebo Q3W for ≥ 48 weeks. PRO instruments included NTDT-PRO (BEYOND only), Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F), and 36-Item Short Form Survey (SF-36). Mixed-effects models with repeated measures estimated least squares mean changes from baseline in PROs. PROs were evaluable in 144 patients (luspatercept 95, placebo 49) from BEYOND and 58 (luspatercept) from LTFU. Luspatercept improved NTDT-PRO tiredness/weakness and shortness of breath domain, FACIT-F fatigue subscale, and SF-36 vitality scores versus placebo through double-blind treatment (generally maintained through week 96). In LTFU patients, significant, meaningful improvements from baseline in FACIT-F fatigue subscale and SF-36 vitality scores were observed within 12 weeks of treatment initiation and maintained for up to 5 years. Other FACIT-F and SF-36 domains improved or were maintained throughout LTFU. Luspatercept offers rapid and durable benefits by improving anemia-related symptoms and quality of life in patients with NTDT. Trial Registration: ClinicalTrials.gov Identifier: NCT03342404; NCT04064060.