US FDA grants efanesoctocog alfa breakthrough therapy designation for hemophilia A

The US Food and Drug Administration (FDA) has granted breakthrough therapy designation to efanesoctocog alfa (BIVV001) for the treatment of people with hemophilia A, a rare and life-threatening bleeding disorder, based on data from the pivotal Xtend-1 phase-III study. Sanofi and Sobi collaborate on the development and commercialisation of efanesoctocog alfa, a statement from Sanofi notified.

Topline results from the pivotal Xtend-1 phase-III study demonstrate efanesoctocog alfa met the primary endpoint, showing a clinically meaningful prevention of bleeds in people with severe hemophilia A over a 52-week period. Importantly, the key secondary endpoint was also met, demonstrating that efanesoctocog alfa was superior to prior prophylactic factor-VIII replacement therapy in preventing bleeding events based on an intra-patient comparison. Efanesoctocog alfa was well-tolerated, and inhibitor development to factor-VIII was not detected. The most common treatment-emergent adverse events (>5% of participants overall) were headache, arthralgia, fall and back pain.

Data from the Xtend-1 phase-III study are expected to be shared at an upcoming medical meeting, and those data will serve as the basis for submission to FDA mid-year 2022. The FDA granted efanesoctocog alfa orphan drug designation in August 2017 and fast track designation in February 2021. The European Commission also granted efanesoctocog alfa orphan drug designation in June 2019. Regulatory submission in the EU will follow availability of data from the ongoing Xtend-Kids paediatric study, expected in 2023, the statement concluded.