Sarepta rockets as eteplirsen seen to significantly benefit Duchenne patients

US RNA-based drug developer Sarepta Therapeutics (Nasdaq: SRPT) saw its shares rocket 200% to $44.93 by close of trading yesterday, when the company said that treatment with its lead exon-skipping compound, eteplirsen, met the primary efficacy endpoint, increase in novel dystrophin, and achieved a significant clinical benefit on the primary clinical outcome, the 6-minute walk test (6MWT) over the placebo/delayed treatment cohort in a Phase IIb extension trial in Duchenne muscular dystrophy (DMD) patients.

Eteplirsen administered once weekly at either 3mg/kg or 50mg/kg for 48 weeks (n=8) resulted in a statistically significant increase (p≤0.001) in dystrophin-positive fibers to 47.0% of normal. The placebo/delayed treatment cohort, which had received 24 weeks of eteplirsen at either 30mg/kg or 50mg/kg following 24 weeks of placebo (n=4), also showed a statistically significant increase in dystrophin-positive fibers to 38.3% of normal (p≤0.009).