Sanofi recently shared positive data from the Phase 3 XTEND-Kids study, which is currently evaluating once weekly prophylaxis with ALTUVIIIO™ in previously treated patients younger than 12 years of age with severe hemophilia A.

ALTUVIIIO is Sanofi’s recombinant factor VIII therapy (rFVIII), developed with proprietary Fc fusion technologies to extend the half-life of the rFVIII, allowing for more sustained protection from bleeds per infusion. The product first received U.S. Food and Drug Administration (FDA) approval in February 2023 for routine prophylaxis and on-demand treatment to control bleeding episodes, as well as perioperative management (surgery) for adults and children with hemophilia A.

Key results from Phase 3 XTEND-Kids were presented during a late-breaking session at the June Annual Meeting of the International Society on Thrombosis and Haemostasis (ISTH) in Montreal, Canada. The data reported during the presentation were based on trial participants who were administered ALTUVIIIO once weekly, for 52 weeks. A new Sanofi press release highlighted the results: 64% of the participants had zero bleeding episodes, 82% experienced zero joint bleeds, and 88% had zero spontaneous bleeds; there were no inhibitors to factor VIII detected; median and mean annualized bleeding rates were 0.00 and 0.89 respectively.

In addition, the company reported the therapy to be well tolerated, with a safety profile comparable to those in the XTEND-1 adult trials. No serious allergic reactions, anaphylaxis, or embolic or thrombotic events were reported. The most common treatment-emergent adverse events (more than 10%) were SARS-CoV-2 test positive, upper respiratory tract infection and fever. No adverse events necessitated a discontinuation of treatment with ALTUVIIIO.

“The results from XTEND-Kids mark an important  breakthrough as we strive for optimized bleed protection as the standard of care. Achieving high-sustained factor activity with once weekly dosing means a freedom from the tradeoffs between treatment burden and efficacy we often see in treating severe hemophilia A, said Lynn Malec, MD, Medical Director of Comprehensive Center for Bleeding Disorders and Associate Investigator at The Versiti Blood Research Institute, and Associate Professor of Medicine and Pediatrics at The Medical College of Wisconsin. “The reliable and consistent bleed protection ALTUVIIIO provides offers confidence for children living with hemophilia and their families to manage hemophilia with less worry.”

View the ALTUVIIIO product page on the FDA website.

Source: Sanofi press release dated June 25, 2023