Sanofi is already a player in the hemophilia A market, but the company is developing another therapy that could better rival Roche’s blockbuster product.Encouraging release of experimental Sanofi therapy preliminary data In a pivotal study, the pharmaceutical giant is now planning to submit an application to seek regulatory approval.
Hemophilia A is a bleeding disorder in which a genetic mutation causes insufficient levels of factor VIII, a blood protein important for blood clotting. Low levels of this protein make it difficult to stop blood flow to a wound. Patients with severe hemophilia A may experience spontaneous bleeding events that affect muscles and joints.
Treatment of severe hemophilia A includes frequent infusions of biological therapy designed to replace factor VIII or its function as a means of preventing bleeding events. Sanofi already sells one such product, Eloctate. Approved by the FDA in 2014, the therapy was developed to be administered every three to five days. Sanofi’s experimental hemophilia A treatment, efanesoctocog alfa, is designed to extend the dosing interval to once a week.
Efanesoctocog alfa is an engineered version of Factor VIII. The therapy uses Amunix’s technology to enable once-weekly dosing, extending the duration of the therapy in circulation. The clinical trial results, released Wednesday, came from a phase 3 study that enrolled 159 patients with severe hemophilia A who had previously received factor VIII replacement therapy. The open-label study design had two arms. One group received a weekly prophylactic dose of Sanofi’s experimental treatment for 52 weeks. The other group received “on-demand” treatment as needed for 26 weeks, followed by weekly preventive treatment for 26 weeks. The primary objective was to measure the annual bleeding rate in the prophylaxis group.
Sanofi and partner Swedish Orphan Biovitrum (Sobi) reported Wednesday that the median annualized bleeding rate for patients in the study was zero. Comparing the experimental treatment with previous prophylactic factor VIII replacement therapy is one of the secondary goals. By this measure, Sanofi reported that its treatments showed a significant reduction in annual bleeding rates. One complication of factor VIII therapy is the immune response, in which the body sees the biological therapy as foreign and produces antibodies against it. Treatment for hemophilia A was well tolerated, with no detectable factor VIII antibodies, Sanofi said.
Sanofi’s experimental hemophilia A therapy has a higher annualized bleeding rate than Eloctate, which had sales of 563 million euros last year, according to the company’s annual report. But Sanofi may be looking at how its experimental hemophilia A therapy might match up with Roche’s Hemlibra. Approved by the FDA in 2017, this bispecific antibody is designed to bind to two coagulation proteins to replace the function of factor VIII. Hemlibra was developed for weekly, two-week or four-week dosing, depending on the severity of the disease. Roche reported 2021 sales of the drug at 3 billion Swiss francs, up 41 percent from the previous year. The company said the drug has a strong market presence, especially in the U.S. and Europe. However, Hemlibra’s label carries a boxed warning about risks such as dangerous cardiovascular problems.
Phase 3 results for efanesoctocog alfa will be presented at a future medical meeting, Anders Ullman, Sobi’s head of research and development and chief medical officer, said in a prepared statement. Sanofi and Soib said the data will form the basis for a regulatory submission the company plans to begin later this year. A submission to the EU is expected when paediatric study data become available in 2023. Deitmar Berger, global head of development and chief medical officer at Sanofi, said in a statement that the positive preliminary data suggest the experimental therapy has transformative potential for hemophilia A therapy.
“We believe efanesoctocog alfa can provide increased protection over a longer period of time and reduce the therapeutic burden of once-weekly dosing, and we look forward to working with regulatory agencies to bring this therapy to patients as quickly as possible,” Berger said.
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