Cephalon sues to block generic Fentora sales, citing dangers

Fentora maker Cephalon is fighting back against potential generic competition. It has asked a federal judge to block the sale of Watson Pharmaceuticals' generic version of the drug, alleging it is potentially dangerous because it contains "a novel salt form" never approved by the FDA.

In its suit brought against the government in the U.S. District Court for the District of Columbia, Cephalon maintains that "[b]arring an injunction," the FDA's approval of Watson's product "will usher into the marketplace a generic drug of untested safety and efficacy."

Cephalon filed its suit four days after a federal judge in Delaware ruled the generic made by Watson didn't infringe two patents exclusively licensed to Cephalon. The company said at the time it is reviewing the decision and is weighing its options. Patents on Fentora are due to expire in 2019, according to the FDA's Orange Book.

FDA spokeswoman Karen Riley said the agency doesn't comment on pending litigation, according to Bloomberg. A phone call to the investor relations department at Watson Pharmaceuticals wasn't immediately returned.

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