The FDA has approved Obizur [Antihemophilic Factor (Recombinant), Porcine Sequence] for the treatment of bleeding episodes in adults with acquired hemophilia A (acquired Factor VIII [FVIII] deficiency).

Acquired hemophilia A is a rare but potentially life threatening bleeding disorder caused by the development of antibodies (immune system proteins) directed against the body’s own FVIII, a protein important for blood clotting. When FVIII is inactivated by these autoantibodies, a person’s blood doesn’t clot normally, resulting in excessive bleeding that can occur spontaneously or following an event such as injury or surgery.

Unlike inherited hemophilia, acquired hemophilia A is not a genetic disorder and affects both males and females. The development of acquired hemophilia A has been related to other medical conditions or health states such as pregnancy, cancer or the use of certain medications. However, in about half of the cases, no underlying cause can be found. Diagnosis of this condition can be difficult and the severity of the bleeding can make treatment challenging.

Obizur contains a recombinant analogue of porcine (pig) FVIII. Porcine FVIII is used because it is similar enough to human FVIII to be effective in blood clotting, but is less likely to be affected by the antibodies against human FVIII that are present in people with acquired hemophilia A.

The safety and efficacy of Obizur was evaluated in a clinical trial of 29 adults with acquired hemophilia A who received Obizur to treat a serious bleeding episode. The trial demonstrated the effectiveness of Obizur in the treatment of bleeding episodes. No safety concerns were identified in the trial.

Obizur received Orphan Drug designation by the FDA because the drug is intended for use in treatment of a rare disease or condition. 

Obizur is manufactured by Baxter Healthcare, based in Westlake Village, Calif.