The United States Food and Drug Administration (US FDA) has approved Baxter International's Obizur [Antihemophilic Factor (Recombinant), Porcine Sequence] for the treatment of bleeding episodes in adults with acquired haemophilia A (AHA), a very rare and potentially life-threatening acute bleeding disorder. Obizur was granted orphan-drug status by the FDA and its review was prioritised based on AHA's classification as a rare disease and the potential for the treatment to address an important unmet medical need.
Obizur is the first recombinant porcine FVIII treatment approved for AHA that allows physicians to manage the treatment's efficacy and safety by measuring factor VIII activity levels in addition to clinical assessments. Obizur replaces the inhibited human factor VIII with a recombinant porcine sequence factor VIII based on the rationale that it is less susceptible to inactivation by circulating human factor VIII antibodies.
''The approval of Obizur is welcome news for the hemophilia community based on the data from the first clinical trial designed specifically for acquired haemophilia A, which found that all patients responded to treatment within 24 hours,'' said Dr. Rebecca Kruse-Jarres, Director of the Haemophilia Care Programme at Puget Sound Blood Center in Seattle and the clinical trial's principal investigator. ''Importantly, this new option to treat bleeding episodes will enable us to measure factor VIII levels, thus giving us an objective marker of hemostasis that can guide dosing and prevent overdosing.''
The approval is based on a global, prospective, controlled, multi-centre phase 2/3 open-label clinical trial that examined the efficacy of Obizur in the treatment of serious bleeding episodes in adults with AHA (29 patients evaluated for safety, 28 evaluated for efficacy). All patients treated with Obizur (28/28) showed a positive response, meaning an effective or partially effective response with bleeding stopped or reduced and clinical improvement, at 24 hours after the initial infusion. A total of 86 per cent (24/28) had successful treatment of the initial bleeding episode. The overall treatment success was determined by the investigator based on the ability to discontinue or reduce the dose and/or dosing frequency of Obizur. Common adverse reactions observed in greater than five per cent of 29 patients in the clinical trial were development of inhibitors to porcine FVIII.
''As a new treatment option with the ability to measure FVIII activity in the body, Obizur will address important unmet needs for patients with acquired haemophilia A, a potentially life-threatening condition,'' said Brian Goff, head of Baxter's hemophilia franchise. ''This approval reflects Baxter's long-standing commitment to discovering new options for haemophilia patients and adds to our portfolio of treatments that reduce the burden of these diseases.''
Obizur will be commercially available in the United States in the coming months and is currently under regulatory review in Europe and Canada.
Obizur [Antihemophilic Factor (Recombinant), Porcine Sequence] is indicated for the treatment of bleeding episodes in adults with acquired haemophilia A.