Merck & Co. ( MRK ) lost another round in its effort to block a competing generic copy of its Nasonex allergy nasal spray from entering the U.S. market. The U.S. Food and Drug Administration this month denied Merck’s petition asking the agency not to approve applications by generic drug makers to sell certain proposed generic forms of Nasonex. Merck, of Whitehouse Station, N.J., had argued the FDA shouldn’t approve any proposed generic copy that has a different formulation than Nasonex. The FDA denial of Merck’s petition follows a federal court ruling earlier this year finding that Apotex Corp.'s proposed generic version of Nasonex doesn’t violate a Merck patent for the drug. Merck has appealed that patent ruling. Both developments remove some obstacles to the market entry of competing generic versions of Nasonex before patent protection expires in 2018, which would hurt sales of the branded drug. The drug, which Merck obtained in its 2009 purchase of Schering-Plough, generated $960 million in sales for the first nine months of 2012. Canada’sApotex wants to sell a generic version of Nasonex that is slightly different from the original. The proposed Apotex product would have the same active ingredient, mometasone furoate, but in a non-water formulation, whereas Merck’s product has a water component. In 2009, Merck filed a patent-infringement lawsuit against Apotex in response to Apotex’s application to market the generic product. Apotex argued that its proposed product wouldn’t infringe upon Merck’s patent because it would be a non-water formulation of mometasone furoate.
