(Reuters) - United Therapeutics Corp said it filed a lawsuit against Novartis AG's generic unit Sandoz, alleging infringement of the biotechnology company's patent on its pulmonary hypertension drug.
In January, Sandoz filed a marketing application with the Food and Drug Administration to sell a copycat version of United Therapeutics' pulmonary hypertension drug Remodulin.
Since United Therapeutics has responded within 45 days of the receipt of Sandoz's notice, the FDA will automatically stay approval for the generic version for up to 30 months under the Hatch-Waxman Act.
In the lawsuit, United Therapeutics alleged that Sandoz's generic version of Remodulin will infringe three of its patents on the drug.
United Therapeutics filed the lawsuit in the District Court for the district of New Jersey.
United Therapeutics shares closed at $46.55 on Wednesday on the Nasdaq.
(Reporting by Anand Basu in Bangalore; Editing by Sriraj Kalluvila)