Benzinga | Jun 3, 2021 06:05AM EDT

United Therapeutics Announces First Patient Enrolled In Phase 3 TETON Study Of Tyvaso In Patients With Idiopathic Pulmonary Fibrosis

United Therapeutics Corporation (NASDAQ:UTHR) announced today that the first patient has enrolled in the phase 3 TETON study, which is expected to evaluate approximately 396 adult patients with idiopathic pulmonary fibrosis (IPF). This 52-week study will evaluate the impact of Tyvaso on a key prognostic indicator for IPF known as forced vital capacity (FVC). IPF is a progressive lung disease characterized by the loss of the ability of the lungs to absorb oxygen, ultimately resulting in respiratory failure and death. IPF is estimated to affect 100,000 people in the United States.

"Despite the availability of two approved products in the therapeutic category, there remains a critical unmet need in IPF," said Steven Nathan, M.D., the Medical Director of the Advanced Lung Disease and Lung Transplant Program at Inova Fairfax Hospital in Falls Church, Virginia, who is also chair of the TETON trial steering committee. Dr. Nathan further added, "We were pleasantly surprised to note the intriguing post-hoc analysis of safety data collected from the INCREASE study that showed a positive impact of inhaled treprostinil on FVC in IPF patients with pulmonary hypertension. In follow-up to this, the TETON study has been designed to validate the potential antifibrotic effects of inhaled treprostinil in IPF patients."

Tyvaso is currently approved by the U.S. Food and Drug Administration (FDA) to treat both pulmonary arterial hypertension, and pulmonary hypertension (PH) associated with interstitial lung disease (PH-ILD). The PH-ILD indication, which includes patients with PH associated with IPF, was added to the Tyvaso label in March 2021 based on the successful results of the INCREASE study. Tyvaso is not approved for use for IPF patients without documented PH.

"The initiation of the TETON study is an important milestone in potentially bringing an improved treatment option to patients with IPF," said Leigh Peterson, Ph.D., United Therapeutics' Senior Vice President of Global Product Development. "The TETON study is an example of our company's flexible development model to expand beyond PH and will help us to better understand the impact of treprostinil in mitigating the FVC decline seen in IPF patients."

The FDA has granted Tyvaso orphan drug designation for the treatment of IPF. As a result, if the FDA updates Tyvaso's labeling to include an IPF indication following a successful TETON study, the FDA should confer seven years of market exclusivity in the United States following marketing approval by FDA.