Executive Summary

About two years ago, the FDA began tightening the statistical standard that companies must meet to demonstrate the efficacy of antibiotics in clinical trials. Meeting that heightened burden of proof meant, in certain instances, substantially increasing trial size and duration-leading some drug companies to drop particular development programs, and even pare back on their development of antibacterials altogether. At the time, the FDA's treatment of antibiotics seemed, to many, part of a broader trend towards a more cautious and conservative approach to drug approval. But it turns out that rather than evidencing a concerted agency effort to more closely scrutinize the effectiveness of antimicrobials, the new policy was apparently instituted by a statistical-minded faction within the FDA whose influence shot up in the absence of strong central leadership. Indeed, that intra-agency power balance has now apparently shifted in favor of medically oriented officials who are more sympathetic to the practical problems faced by antibiotic drugmakers. But while pharmaceutical company officials voice optimism that they will be able to work out a reasonable new set of efficacy guidelines with the FDA, there's a lingering concern that the power vacuum at the top of the agency will continue to create uncertainty and unpredictability for an industry whose long-term development cycles make it so dependent on regulatory consistency.