United Therapeutics Commences Litigation to Ensure Fairness in the Drug Review Process

United Therapeutics Corporation (Nasdaq: UTHR) announced today the commencement of litigation with the United States Food and Drug Administration (FDA). In the litigation, United Therapeutics alleges that the FDA mistakenly permitted Liquidia Corporation (Liquidia) to skirt longstanding FDA rules, precedents, and procedures on how pending drug approval applications are handled by the agency. In doing so, the FDA inappropriately denied United Therapeutics its right to obtain a stay of Liquidia’s final approval until United Therapeutics’ pending patent infringement claim against Liquidia can be resolved.

This litigation addresses the FDA’s handling of Liquidia’s unlawful amendment to a pending new drug application (NDA) seeking to add a second indication, pulmonary hypertension associated with interstitial lung disease (PH-ILD), to the label of its proposed inhaled dry powder treprostinil product. United Therapeutics alleges in the litigation that the FDA’s rules, precedents, and procedures require that Liquidia seek approval for this second indication by filing a new NDA rather than filing an amendment to a pending NDA. United Therapeutics believes this distinction is critical to ensure the proper review and approval of new drug applications in a fair, equitable manner consistent with the FDA’s prior practices with which industry has complied for decades.

Before 2021, every clinical trial of drugs approved for the treatment of pulmonary hypertension that were studied for the treatment of PH-ILD failed. Some approved PH therapies worsened patients’ pulmonary hypertension, and PH-ILD remained a disease for which there were no approved therapies.

Notwithstanding this clear record of failure by others in PH-ILD, United Therapeutics took the bold step at considerable expense to conduct an innovative pivotal trial of Tyvaso (treprostinil) Inhalation Solution for the treatment of PH-ILD. This trial, called INCREASE, was the largest and most comprehensive completed study of patients with PH-ILD, and its successful results led the FDA to approve Tyvaso as the first ever treatment for PH-ILD in March 2021. The results of the INCREASE study were published in The New England Journal of Medicine in January 2021.