Lung-Disease Drug Fight Exposes Fault Lines in Patent System

United Therapeutics Corp. is taking its founder’s ethos to “make generic barbaric” to heart as it fights a multifront battle against a rival’s potential competitor to the blockbuster lung-disease treatment Tyvaso.

Martine Rothblatt has said she launched the biotech company in 1996 to find a cure for her daughter’s rare, life-threatening disease that causes high blood pressure in the lungs, pulmonary arterial hypertension. UTC, she’s said, wanted to improve the convenience or efficiency of a patient’s treatment—and zealously defend those innovations with new patents extending decades beyond the life of the active ingredient’s original patent—to render cheaper copies of its ...