(224) Real-world experience with efanesoctocog alfa in patients with moderate and severe hemophilia A: Final analysis of the Adelphi hemophilia wave III disease specific programmeTM

Background: : Efanesoctocog alfa is a first-in-class, once-weekly Factor VIII replacement therapy that provides high, sustained factor levels for patients with hemophilia A (PwHA).

Objective: : To describe the clinical outcomes and treatment landscape among PwHA who received efanesoctocog alfa prophylaxis.

Methods: : This retrospective, observational study analyzed data collected between July 2023 and December 2024 from the United States (US)-based real-world Hemophilia Wave III Disease Specific ProgrammeTM. The cross-sectional survey included male PwHA (moderate or severe) receiving efanesoctocog alfa. Data were obtained via physician-completed patient record forms. Patient characteristics and treatment landscape were analyzed for patients receiving prophylactic efanesoctocog alfa for any duration (Group 1), and those receiving for ≥170 days (Group 2). Bleed outcomes were analyzed only for Group 2.

Results: : This analysis included 84 patients in Group 1 and 44 patients in Group 2. Mean (SD) age was 23.4 (13.0) and 24.2 (11.3) years, respectively, with 89.3% and 93.2% never having had inhibitors. Mean (SD) duration since initiating efanesoctocog alfa until data collection was 192.3 (118.4) days in Group 1 and 263.3 (77.3) days in Group 2.
Among Group 2 (n=40), estimated mean (SD) annualized bleed rate (ABR) significantly decreased from 0.97 (2.25) in 12 months prior to initiating efanesoctocog alfa to 0.21 (0.6) post-initiation (p=0.0091). Prior to initiation, 62.5% patients had no bleeds, 22.5% had 1 bleed, and 5% (each) had 2, 3, 5+ bleeds. Following initiation, 87.5% reported no bleeds, 7.5% had 1 bleed, and 5% had 2 bleeds.
In Groups 1 and 2, mean (SD) dosing interval for efanesoctocog alfa was every 7.0 (0.2) and 7.0 (0.3) days, respectively, with mean (SD) dose of 49.7 (2.4) and 49.5 (3.1) IU/kg.
Physicians reported satisfied or completely satisfied with following treatment attributes in Groups 1 and 2, respectively: managing patients’ hemophilia (91.8% and 97.7%), overall safety (96.5% and 97.7%) and efficacy (94.1% and 100%), administration frequency (92.9% and 97.7%) and duration (90.6% and 100%).

Conclusions: : Results from this real-world survey demonstrate that prophylactic efanesoctocog alfa use in PwHA was associated with lower ABRs than in the 12 months prior to treatment initiation. Dose and frequency of efanesoctocog alfa administration were consistent with the US prescribing information. Physicians reported satisfaction with its efficacy, safety, and administration attributes. These findings highlight efanesoctocog alfa as an effective alternative to existing prophylactic treatments for PwHA.

Sponsorship:: Sanofi