ViroPharma falls as FDA approves Vancocin generics

ViroPharma Inc. (NASDAQ:VPHM) fell $6.17 (22%) to $22.44 on Tuesday after FDA approved three generic versions of the company's oral antibiotic Vancocin vancomycin. The agency also denied ViroPharma's Citizen's Petition seeking to delay approval of any generics and require their sponsors to use in vivo clinical data to establish bioequivalence. ViroPharma said it plans to file a complaint against FDA in the U.S. District Court for the District of Columbia seeking an injunction to overturn FDA's approval of the generics. ViroPharma said it plans to launch an authorized generic of vancomycin soon.

In a letter denying the petition, FDA upheld the validity of 2008 draft guidance recommending in vitro dissolution studies to establish bioequivalence (see BioCentury, Aug. 2, 2010). ...