Once weekly efanesoctocog alfa provides superior bleeding prevention to prestudy prophylaxis for patients with severe hemophilia A, according to a study published in the Jan. 26 issue of the New England Journal of Medicine.

Annette von Drygalski, M.D., Pharm.D., from the University of California in San Diego, and colleagues conducted a phase 3 study involving patients aged 12 years or older with severe hemophilia A. Group A (133 patients) received once-weekly prophylaxis with efanesoctocog alfa for 52 weeks and group B (26 patients) received on-demand treatment with efanesoctocog alfa for 26 weeks, followed by once-weekly prophylaxis with efanesoctocog alfa for 26 weeks.

The researchers found that the median annualized bleeding rate was 0 and estimated mean annualized bleeding rate was 0.71 in group A. There was a decrease observed in the mean annualized bleeding rate from 2.96 to 0.69, which showed superiority over prestudy factor VIII prophylaxis. In the overall population, 97 percent of bleeding episodes resolved with one injection of efanesoctocog alfa.

Mean factor VIII activity >40 IU/dL for the majority of the week and 15 IU/dL at day seven was seen with weekly prophylaxis of efanesoctocog alfa. Physical health, pain intensity, and joint health were improved significantly with efanesoctocog alfa prophylaxis for 52 weeks (group A). Efanesoctocog alfa had an acceptable side-effect profile in the overall study population; development of inhibitors to factor VIII was not identified.

“Collectively, these results show that by maintaining high sustained factor VIII activity, once-weekly efanesoctocog alfa provided substantial improvements in clinical outcomes and quality of life for patients with severe hemophilia A,” the authors write.

The study was funded by Sanofi and Sobi, the manufacturers of efanesoctocog alfa.

More information: Annette von Drygalski et al, Efanesoctocog Alfa Prophylaxis for Patients with Severe Hemophilia A, New England Journal of Medicine (2023). DOI: 10.1056/NEJMoa2209226

Cindy Leissinger, Another Victory for Patients with Hemophilia, New England Journal of Medicine (2023). DOI: 10.1056/NEJMe2216176

Journal information: New England Journal of Medicine