Sangamo Therapeutics and Pfizer announced the European Medicines Agency (EMA) has granted orphan medicinal product designation (OMPD) to SB-525, a clinical stage cDNA gene therapy candidate for hemophilia A. The EMA's OMPD is granted to medicines intended for the treatment, prevention or diagnosis of life-threatening or chronically debilitating conditions that are rare and affect less than five in 10,000 persons in the European Union (EU). The designation provides incentives to advance the development and commercialization of orphan medicines, which include access to the EU centralized authorization procedure and potential for market exclusivity for a period of up to ten years.
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 being investigated as a single-treatment strategy intended to provide continuous, therapeutic expression of Factor VIII protein.
In May 2017, Sangamo and Pfizer entered into an exclusive, global collaboration and license agreement to develop and commercialize gene therapy programs for hemophilia A, including SB-525. The U.S. Food and Drug Administration (FDA) has already granted Orphan Drug and Fast Track designation to SB-525 for the treatment of hemophilia A. The FDA has also cleared an Investigational New Drug application for this program, and a Phase 1/2 clinical trial evaluating SB-525 in adults with hemophilia A is now open and screening subjects for enrollment. Initial data from this study are expected in late 2017 or early 2018. Under the collaboration and license agreement between the two companies, Pfizer will be responsible for any subsequent clinical trials and the commercialization of SB-525.
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 U.S. living with the disorder.