Sanofi has announced that its efanesoctocog alfa has been awarded breakthrough therapy designation by the US Food and Drug Administration (FDA). According to the pharmaceutical company, the drug candidate is the first factor VIII therapy to be awarded breakthrough therapy designation by the agency.
Hemophilia A is diagnosed in about one in 5,000 male babies born each year, with occurrence much more rarely in females. The lifelong condition impacts the ability of a patient’s blood to clot due to a coagulation factor deficiency.
People diagnosed with hemophilia can experience bleeding episodes that can cause pain, irreversible joint damage, and life-threatening hemorrhages. Unmet medical needs remain for people with hemophilia to strengthen protection, reduce treatment burden, and improve quality of life.
Efanesoctocog alfa is a novel and investigational factor VIII therapy that is intended to offer normal to near-normal factor activity levels for the majority of a patient’s week in a once-weekly prophylactic treatment regimen. This designation is based on the XTEND-1 Phase III study data, which reportedly demonstrated clinically meaningful prevention of bleeds and superiority in the prevention of bleeding episodes compared to prior prophylaxis factor treatment.
John Reed, Sanofi’s global head of research and development, said, “The breakthrough therapy designation highlights efanesoctocog alfa’s potential to transform treatment for people with hemophilia A by providing higher protection for longer duration. This potential new class of factor VIII therapy represents how we are boldly advancing science to address unmet needs for the hemophilia community. We are excited to work with regulatory authorities during the filing and review of this innovative therapy.”
Sanofi has collaborated on the development and commercialization of efanesoctocog alfa with Sobi. Breakthrough therapy designation is designed to expedite the development and review of drugs aimed at serious and life-threatening conditions; in order to qualify for the designation, a treatment candidate must show preliminary clinical evidence that it may offer a substantial improvement on clinically significant endpoints over available therapies.
Anders Ullman, head of research and development and chief medical officer with Sobi, said, “This designation supports the innovation of efanesoctocog alfa and acknowledges its potential to fulfill an unmet medical need for people living with hemophilia A. We are committed to transforming lives for people living with rare diseases, and this is a testament to the medical innovation that science can bring.”
According to the two pharmaceutical companies, topline results from the XTEND-1 Phase III study demonstrate efanesoctocog alfa met the primary endpoint, showing clinically meaningful prevention of bleeds in people with severe hemophilia A over a 52-week period. The key secondary endpoint reportedly was also met, demonstrating that the treatment compared favorably to prior prophylactic factor VIII replacement therapy in preventing bleeding events based on an intra-patient comparison. Efanesoctocog alfa also reportedly 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 Phase III study are expected to be shared at an upcoming medical meeting; those data will serve as the basis for submission to the 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 the availability of data from the ongoing XTEND-Kids pediatric study, expected in 2023.