What’s the Problem With Elmiron?

In 1985, Elmiron was granted an FDA orphan drug designation, which is defined as “those intended for the safe and effective treatment, diagnosis, or prevention of rare diseases/disorders that affect fewer than 200,000 people in the US or that affect more than 200,000 persons but are not expected to recover the costs of developing and marketing a treatment drug.”  However, in 1993, the FDA issued its first non-approval letter for Elmiron, citing issues with both clinical trial investigators and clinical trial results.  In 1994, the FDA issued its second non-approval letter citing insufficient clinical trial evidence to establish efficiency.  Upon reviewing the clinical trial results, the FDA issued a response that the new drug application Elmiron (NDA) awas NOT approvable.