The designation allows expedited development and FDA review of the gene therapy currently undergoing a Phase 1/2 trial as a potential one-time therapy. The trial is recruiting patients.
Spark Therapeutics, a gene therapy company, developed the SPK-FIX program which focuses on the development of potential therapeutic solutions for Hemophilia B. The company entered a collaboration with Pfizer in December 2014, to develop and commercialize the product’s candidates.
SPK-9001 is a novel engineered adeno-associated virus (AAV), which in nature causes no disease and is consistently used for gene delivery. It expresses an optimized human factor IX variant, the deficient protein that causes haemophilia B which leads to deficient blood coagulation and an increased risk of bleeding.
According to data presented at the 21stCongress European Hematology Association (EHA) in June by trial investigator Dr. Spencer Sullivan, of the University of Mississippi Medical Center, four patients in the study who received the one-time therapy showed consistent and sustained factor IX activity levels. After a combined 58 weeks of observation, none of the patients needed regular infusions of factor IX concentrates to prevent bleeding events, and none experienced negative side effects.
A final report on primary outcome measures is expected in September 2018.
“We are extremely pleased to have been granted breakthrough therapy designation for SPK-9001, which has shown early promise in achieving our goal of eliminating the need for regular infusions to control and prevent bleeding episodes in patients with hemophilia B through a potentially one-time, intravenous administration of a highly optimized gene therapy,” Jeffrey Marrazzo, chief executive officer of Spark Therapeutics said in a press release. “Together with Pfizer, we look forward to working closely with the FDA to bring SPK-9001 to patients as quickly and responsibly as possible.”