Eteplirsen (AVI Biopharma) results in Phase IIb study in Duchenne Muscular Dystrophy

Treatment with eteplirsen from AVI Biopharma met the primary efficacy endpoint in a randomized, double-blind, placebo-controlled Phase IIb study in boys with Duchenne muscular dystrophy (DMD). Eteplirsen administered once weekly at 30mg/kg over 24 weeks resulted in a statistically significant (p ? 0.002) increase in novel dystrophin (22.5% dystrophin-positive fibers as a percentage of normal) compared to no increase in the placebo group. The top line Phase II data showed that eteplirsen produced the protein dystrophin, but did not provide clinical benefits for DMD patients, such as improvements in walking. However the company stated that 24 weeks is not long enough for eteplirsen to provide clinical benefits, such as slowing or stopping disease progression that impairs walking. AVI will conduct longer term studies with patients who took the drug in Phase IIb and move patients who took a placebo to long-term dosing at 30 mg/kg and 50 mg/kg.