FDA Grants Priority Review to Hemlibra for Treatment of Hemophilia A Without Factor VIII Inhibitors

Hemlibra (emicizumab-kxwh) was recently granted priority review status by the U.S. Food and Drug Administration following the agency’s acceptance of Genentech’s supplemental biologics license application (sBLA) for the treatment for people with hemophilia A without factor VIII inhibitors.

Priority review status is granted to therapies that could potentially improve the treatment, prevention, or diagnosis of a serious condition. A final decision on approval is expected by Oct. 4.

Hemlibra is a prescription medicine used for routine preventive treatment to reduce the frequency of bleeding episodes in adults and children with hemophilia A with factor VIII inhibitors.

“People with hemophilia A can face significant challenges in managing their condition and may need to adapt their daily lives to avoid bleeds and accommodate treatment,” Sandra Horning, MD, chief medical officer and head of global product development at Genentech, said in a press release.

“We believe the FDA’s decision to grant Priority Review to Hemlibra underscores its potential to improve the standard of care for people without factor VIII inhibitors and to help reduce treatment burden by offering more flexible subcutaneous dosing options. We look forward to working with the FDA to hopefully bring Hemlibra to all people with hemophilia A as quickly as possible.”

FDA approval of the sBLA is based on data from the Phase 3 HAVEN clinical trial (NCT02847637), a study designed to evaluate the effectiveness, safety, and properties of preventive treatment with Hemlibra versus no preventive treatment in people with hemophilia A without factor VIII inhibitors.

It included 152 patients with hemophilia A, ages 12 and older, who were previously treated with factor VIII therapy either as needed or for prevention.

Results from the HAVEN 3 trial, presented at the World Federation of Hemophilia 2018 World Congress in May, showed a 96% reduction in treated bleeds in those on weekly treatment (1.5 mg/kg), and a 97% reduction in patients treated every two weeks (3 mg/kg) compared with patients in the control group, who only got treatment on an as-needed basis.

Moreover, a subgroup of patients who had been enrolled in a previous prospective, non-interventional study had a 68% reduction in number of bleeds, compared with prior factor VIII preventive therapy.

Hemlibra was approved for routine prevention to reduce the frequency of bleeding episodes in adults and children with hemophilia A with factor VIII inhibitors in the United States in November 2017, based on results from the HAVEN1 (NCT02622321) trial in adolescents and adults, and HAVEN2 (NCT02795767) in children.

In Europe, Hemlibra was approved for routine prevention of bleeding episodes in people with hemophilia A with factor VIII inhibitors in February.

Hemlibra was also granted breakthrough therapy designation by the FDA in April, based on HAVEN 3 results. This status grants the therapy expedited development and review.

The HAVEN program also includes HAVEN 4 (NCT03020160), the most recent results of which showed that 56.1% had zero bleeds, and 90.2% had three or fewer bleeds over at least 24 weeks of treatment, regardless of inhibitor status.

In a recent special story by Hemophilia News Today, Gallia Levy, a hematologist and associate group medical director for Genentech, detailed the program’s results, adding that “all research was focused on prolonging the half-life of factor VIII therapies … there was very little research focused at the inhibitor population, which is the population really with the highest unmet need in hemophilia.”

“The ultimate goal for the development program, when we started, was to have Hemlibra approved for hemophilia A patients with and without inhibitors, with three dosing schedules: every week, every two weeks, and every four weeks,” she said.