FDA fast-tracks Sangamo/Pfizer hemophilia A treatment

WASHINGTON —  Sangamo Therapeutics announced on Tuesday that the Food and Drug Administration has granted Fast Track designation to SB-525, the company's clinical stage cDNA gene therapy candidate for hemophilia A, which is being developed as part of an exclusive, global collaboration and license agreement with Pfizer.

The FDA's Fast Track designation is designed to facilitate the development and expedite the review of drugs and biologics to treat serious conditions and fill an unmet medical need.

SB-525 uses a recombinant adeno-associated virus (rAAV) to deliver a human Factor VIII cDNA construct and proprietary, synthetic liver-specific promoter to the nucleus of liver cells with a single infusion. The therapy is designed as a single treatment strategy intended to provide continuous, therapeutic expression of Factor VIII protein. It has already received Orphan Drug designation from the FDA.

Hemophilia A is a monogenic, rare bleeding disorder in which the blood does not clot normally. It is caused by mutations in the F8 gene which encodes Factor VIII clotting protein that helps the blood clot and stop bleeding when blood vessels are injured. Individuals with this mutation experience bleeding episodes after injuries and spontaneous bleeding episodes that often lead to joint disease such as arthritis. According to the Centers for Disease Control and Prevention, hemophilia occurs in about one of every 5,000 male births, with an estimated 20,000 males in the United States living with the disorder.