The FDA rejected IntelGenx and RedHill Biopharma's dissolvable migraine treatment VersaFilm due to problems with a third-party manufacturer, the companies said. The two still believe they can sway regulators and get the drug on the U.S. market. The agency's complete response letter takes no issue with VersaFilm's data and demands no additional studies, according to the pair, and the companies figure they can provide an adequate response within a few weeks. The drug is a film formulation of rizatriptan benzoate, the active ingredient in Merck's ($MRK) Maxalt. News