Quality of life and functional improvements with efanesoctocog alfa in patients with moderate-to-severe Hemophilia A: A real-world survey

Abstract Background: Hemophilia A (HA) is a rare X-linked bleeding disorder characterized by deficiency or dysfunction of clotting factor VIII (FVIII), resulting in breakthrough bleeding that can cause joint damage and impair patients' quality of life (QoL). Efanesoctocog alfa (Efa) is a first-in-class high-sustained FVIII replacement therapy designed to decouple FVIII from endogenous von Willebrand factor to increase its half-life. It was approved in the United States (US) in February 2023 for once weekly prophylaxis of bleeds in patients with HA without inhibitors. Real-world data on patient experience with prophylactic Efa are emerging. Aim: To assess real-world, patient-reported experiences with prophylactic Efa in individuals with moderate-to-severe HA without inhibitors. Methods: This study used data from the Adelphi Real World Hemophilia Patient Survey, a cross-sectional survey of people with HA receiving Efa, collected between December 2024 and February 2025. Eligible participants were adult males (≥18 years) in the US with moderate-to-severe HA (based on baseline clotting factor levels), who had been receiving Efa prophylaxis for ≥6 months at the time of survey completion. The survey captured patient demographics, clinical and humanistic burden, treatment satisfaction, and treatment patterns. Descriptive analyses were used for continuous and categorical variables. Where applicable, symmetry tests or McNemar tests were used to compare outcomes before and after initiating Efa (significance threshold: p<0.05). Results: Thirty-one patients were included. The mean (SD) patient age was 40.2 (15.5) years, and the mean (SD) body mass index was 28.3 (6.8) kg/m². Most patients were White (80.6%), worked full-time (61.3%), commercially insured (54.8%), and had severe HA (74.2%). The majority (83.9%) of patients reported never having inhibitors. The most recent treatments prescribed prior to Efa were standard half-life products (64.5%), extended half-life products (45.2%), emicizumab (32.3%), and others (6.5%) (groups exceed 100% as multiple treatments were used either prophylactically or on-demand). The median (IQR) duration of Efa use was 388.0 (266.0–557.0) days, and the mean (SD) proportion of doses reportedly taken as prescribed was 95.0% (7.3%). Most patients reported being “completely satisfied” or “satisfied” with Efa in terms of overall experience (93.5%), bleed prevention (96.8%), and improvement in patients' ability to perform physical activity (79.3%) (n=29). When comparing Efa to prior therapies for hemophilia control, 83.9% rated it as better, 9.7% as comparable, and 6.5% as worse. After Efa initiation, relative improvements were observed in daily functioning and physical activity. A greater proportion of patients reported no difficulty with any activities of daily living after receiving Efa (51.6% pre- to 67.7% post-switch; p=0.1250). The proportion of patients reporting difficulty with walking decreased following switching (35.5% pre- to 16.1% post-switch; p=0.0312). The number of patients who often avoided physical activity was higher pre-switch than post switch; (38.7% pre to 16.1% post-switch; p=0.0186). Since starting Efa, a significantly higher proportion of patients reported no longer taking preventive measures (i.e., increasing the regular dose of prophylactic treatment, taking an extra dose of factor, or other), increasing from 19.4% pre- to 58.1% post-switch; p=0.0005. Although not statistically significant, fewer patients reported increasing their regular prophylactic doses or taking extra factor doses ahead of physical activity after switching (22.6% pre- to 6.5% post-switch; p=0.0625, and 32.3% pre- to 19.4% post-switch; p=0.1250, respectively). Conclusions: This is the first real-world, patient-reported outcomes study of prophylactic Efa use among patients with moderate-to-severe HA. Most patients rated Efa more favorably for hemophilia control compared to previous regimens. Improvements were observed in daily functioning, participation in physical activity, and a reduced need for preventive measures and additional prophylactic doses.