(Reuters) -Texas Attorney General Ken Paxton sued Bristol Myers Squibb and Sanofi, accusing the drugmakers of failing to disclose that Plavix, which is used to prevent blood clots, does not work effectively for many patients.

Paxton said on Thursday the lack of disclosure caused patients to be prescribed a “substantially inadequate or inappropriate” medication, violating the Texas Health Care Program Fraud Prevention Act.

(Reporting by Jonathan Stempel in New York, Editing by Franklin Paul)

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