Efanesoctocog alfa prevents bleeding episodes in haemophilia A patients

Factor VII - Efanesoctocog alfa is a novel and investigational recombinant factor VIII therapy that is designed to extend protection from bleeds with once-weekly prophylactic dosing for people with haemophilia A.

Sanofi and Sobi have announced positive topline results from the Xtend-1 Phase III study evaluating the safety, efficacy and pharmacokinetics of efanesoctocog alfa (BIVV001) in previously treated patients up to 12 years of age with severe haemophilia A.

The study met the primary endpoint, showing a clinically meaningful prevention of bleeds in people with severe haemophilia A receiving weekly prophylaxis with efanesoctocog alfa over a period of 52 weeks. The median annualised bleeding rate (ABR) was 0 with a mean ABR of 0.71. The key secondary endpoint was also met, demonstrating once-weekly efanesoctocog alfa was superior to prior prophylactic factor VIII replacement therapy, showing a statistically significant reduction in ABR based on intra-patient comparison. Efanesoctocog alfa was well-tolerated, and inhibitor development to factor VIII was not detected. The most common treatment-emergent adverse events (less than five percent of participants overall) were headache, arthralgia, fall and back pain.

“While advances have been made in the treatment of haemophilia, unmet medical needs still exist,” commented Dr Dietmar Berger, Global Head of Development and Chief Medical Officer, Sanofi. “These positive topline data, showing a very low annualised bleeding rate, enhance efanesoctocog alfa’s potential to transform haemophilia A therapy. We believe efanesoctocog alfa provides higher protection for longer duration with reduced treatment burden of once-weekly dosing, and we look forward to working with regulators to bring this therapy to patients as soon as possible.”

Haemophilia A is a rare, genetic disorder in which the ability of a person’s blood to clot is impaired due to a lack of factor VIII. Haemophilia A occurs in about one in 5,000 male births annually, and more rarely in females. People with haemophilia can experience bleeding episodes that can cause pain, irreversible joint damage and life-threatening haemorrhages.

Efanesoctocog alfa is a novel and investigational recombinant factor VIII therapy that is designed to extend protection from bleeds with once-weekly prophylactic dosing for people with haemophilia A. It builds on the innovative Fc fusion technology by adding a region of von Willebrand factor and XTEN^® polypeptides to extend its time in circulation. It is the first investigational factor VIII therapy that has been shown to break through the von Willebrand factor ceiling, which imposes a half-life limitation on current factor VIII therapies.

“We believe once-weekly efanesoctocog alfa has the potential to represent a new class of factor VIII therapy designed to provide high sustained factor VIII levels near normal for the majority of the week,” stated Dr Anders Ullman, Head of R&D and Chief Medical Officer, Sobi.

The data will be the basis for submission to regulatory authorities around the globe beginning this year.