Executive Summary

The January 2010 approval for Acorda Therapeutics Inc.'s oral multiple sclerosis therapy Ampyra (dalfampridine) is an impressive accomplishment - by any account. The company took a drug that failed one development program and resurrected it so that it ultimately won FDA approval and is fast becoming a commercial success. Every drug and indication has its challenges, and gaining FDA approval is never simple. But Acorda's challenges were greater than most. MS causes demyelination, which leads to slower nerve conduction; gait problems are one of its most common symptoms. Acorda was first to tackle the walking problem, and it faced the challenge of proving a novel benefit in a disease that is highly debilitating, progressive, and variable. Patients can feel better one day, worse another, for reasons no one entirely understands, making it difficult to discern a drug's impact. Along the way, Acorda also had to contend with the usual complications: development setbacks, edgy investors and negotiations with FDA. To demonstrate that its new drug for walking impairment was efficacious, Acorda devised an innovative responder rate analysis, which used a novel endpoint and an unusual statistical analysis to identify subsets of responders.