The Food and Drug Administration (FDA) has granted Fast Track designation to SRP-9001 (AAVrh74.MHCK7.micro-dystrophin; Sarepta Therapeutics) for the treatment of Duchenne muscular dystrophy (DMD).

SRP-9001 is an investigational gene transfer therapy designed to deliver the micro-dystrophin-encoding gene to muscle tissue for the targeted production of the micro-dystrophin protein. 

The Fast Track designation is supported by data from an open-label phase 1/2a study that evaluated the safety and tolerability of SRP-9001 in 4 patients aged 4 to 7 years with DMD. Patients received a single dose of treatment infused through a peripheral limb vein over 1.25-1.5 hours.

Results showed that treatment with SRP-9001 was found to be safe and well tolerated at 1 year, with all adverse events being mild or moderate. Study investigators also reported that micro-dystrophin gene transfer “was associated with robust micro-dystrophin expression, reduced serum creatine kinase levels, and functional improvement as measured by the North Star Ambulatory Assessment.”

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The Company expects results from an ongoing phase 2 study in early 2021.

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1. Sarepta therapeutics receives fast track designation for SRP-9001 micro-dystrophin gene therapy for the treatment of duchenne muscular dystrophy. Published July 24, 2020. Accessed July 28, 2020. 

2. Sarepta therapeutics announces positive safety and efficacy data from the SRP-9001 micro-dystrophin gene therapy trial published in JAMA Neurology. Published June 15, 2020. Accessed July 28, 2020.