Regulatory Updates, In Brief

FDA approves Acorda's MS drug: FDA approved Ampyra (dalfampridine) with the novel indication of improvement in walking ability in adults with multiple sclerosis, despite a questionably meaningful responder rate and increased risk of seizure. The Jan. 22 approval is a huge win for Acorda, which took a risk developing a MS drug with an indication that had never before been studied and for which there is no target for treatment. The approval also showcases FDA's confidence that the drug will provide a clinical benefit to some patients - a point of contention during Ampyra's advisory committee review. Despite showing that Ampyra patients had statistically significant faster walking speeds than those on placebo, FDA briefing documents noted that the magnitude of improvement was small and clinical significance was uncertain (1"The Pink Sheet," Oct. 26, 2009). Adding to the uncertainty was the drug's increased risk of seizures - a widely acknowledged safety signal for 4-aminopyridine and other pyridine compounds