Bayer files for European approval of hemophilia A drug BAY 81-8973

German pharma major Bayer (BAYN: DE) has filed an application for marketing authorization to the European Medicines Agency for BAY 81-8973, a recombinant Factor VIII (rFVIII) compound, for the treatment of hemophilia A in children and adults. Bayer's shares  gained 3.4% to 120.95 euros on Friday.

BAY 81-8973 is a full-length recombinant factor VIII which has demonstrated clinical evidence of efficacy when used for prophylaxis twice or three times per week, with standard dosages. Bayer Healthcare plans to file BAY 81-8973 for approval in other countries in the coming months. The approval of BAY 81-8973, will supplement Bayer’s portfolio that includes Kogenate FS, which is indicated for the treatment and prevention of bleeding in adults and children with hemophilia A.

“Clinical data from the LEOPOLD trials show that BAY 81-8973 provides bleeding control in people with severe hemophilia A when infused either twice per week or three times per week - with standard dosages,“ said Johannes Oldenburg, a member of the Clinical Study Steering Committee and Head of the University of Bonn’s Institute of Experimental Hematology and Transfusion Medicine. “Flexible dosing gives patients and their doctors greater choice in matching the right treatment regimen to each person’s therapeutic requirements,” he added.

Clinical backing for submission

The submission was based on positive results from three Phase III trials in children, adolescents and adults including a total of 204 subjects. The LEOPOLD II clinical trial demonstrated the superiority of prophylaxis versus on-demand therapy with BAY 81-8973. Results show a 93.3%reduction in median annualized bleeding rate (ABR) in the twice-per-week prophylaxis arm versus on-demand and a 96.7% reduction in the three-times-per-week arm versus on-demand. Patients in this study were randomized between the three treatment arms.

The actual median ABRs observed were four bleeds when treated two times per week and two bleeds when treated three times versus 60 in the on-demand group. Patients treated in both the twice-per-week arm and the three-times-per-week arm maintained adequate bleed control while using 20 to 40 IU/KG. When used on-demand, 95% of bleeds were controlled with one or two infusions. No clinically relevant treatment-related adverse events occurred and no inhibitor formation was observed. In the pediatric trial including 51 pre-treated children <12 years of age, BAY 81-8973 demonstrated good efficacy with twice or three times per week or every other day prophylaxis regimens, and no inhibitors were observed. A clinical study in previously untreated patients is ongoing. Bayer presented the LEOPOLD II results at the World Federation of Hemophilia (WFH) 2014 World Congress in May 2014.