The suit comes as the company, United Therapeutics, faces new competition from other firms trying to sell similar treatments on the generic market.
Silver Spring-based United Therapeutics filed suit Aug. 4 in U.S. District Court for the District of Columbia, alleging the firm is entitled to a seven-year period of exclusive sale of the drug’s oral formulation.
Media representatives from the Food and Drug Administration and the Department of Health and Human Services declined to comment, citing policies against speaking about on pending litigation.
The case is based on the Orphan Drug Act, a 1983 law meant to give pharmaceutical companies a stronger financial incentive to pursue cures for rare diseases. The law gives drug manufacturers a seven-year period to sell the drug free of competition, with the hope that the period of monopoly status will make the market for these rare drugs more attractive to drugmakers.
United Therapeutics’ drug is an orally administered treatment called Orenitram, which treats the rare blood-pressure disease pulmonary arterial hypertension. The often-fatal condition is estimated to affect less than 0.01 percent of the population.
