United Therapeutics Corporation (NASDAQ:UTHR) shares are up during Monday’s premarket session following the announcement that the TETON-1 Phase 3 pivotal study of nebulized Tyvaso (treprostinil) has met its primary endpoint.

Tyvaso Meets Primary Endpoint

The study demonstrated that nebulized Tyvaso (treprostinil) significantly improved forced vital capacity (FVC) by 130.1 mL compared to placebo.

The drug also reduced the risk of clinical worsening in patients with idiopathic pulmonary fibrosis (IPF).

IPF is a chronic, progressive lung disease characterized by irreversible scarring of lung tissue, leading to severe breathing difficulties. ‘Idiopathic’ means the cause is unknown.

Secondary Endpoints And Survival Data Offer Mixed Signals

Integrated analyses of the TETON-1 and TETON-2 studies showed statistically significant treatment effects across most secondary efficacy endpoints.

Overall survival at week 52 trended in favor of Tyvaso but did not meet statistical significance.

The treatment was well-tolerated, with no new safety signals reported, reinforcing the robustness of the findings across various patient subgroups.

United Therapeutics Regulatory Pathway And Upcoming Data Presentation

United Therapeutics plans to seek priority review of a supplemental New Drug Application, to be submitted to the U.S. Food and Drug Administration (FDA) by the end of this summer, to add IPF to the labeled indications based on data from the TETON-1 and TETON-2 studies.

Additional TETON-1 study results and data from the integrated analyses of TETON-1 and TETON-2 will be presented at the American Thoracic Society Annual Meeting in May 2026.

Ongoing Studies Expand Tyvaso’s Potential Use

TETON-PPF is evaluating the use of nebulized Tyvaso in progressive pulmonary fibrosis (PPF) in patients globally, and enrollment is ongoing.

The FDA has approved Tyvaso (treprostinil) Inhalation for pulmonary arterial hypertension.

United Therapeutics Lung/Heart Disease Data

Earlier in March, United Therapeutics shared positive news regarding its drug ralinepag, which achieved a significant milestone in clinical trials.

The phase 3 ADVANCE OUTCOMES study of ralinepag met its primary endpoint.

The study showed a 55% reduction in the risk of clinical worsening events in patients with pulmonary arterial hypertension (PAH).

The study showed that ralinepag increased the odds of clinical improvement by 47% in predominantly pre-treated patients. The company plans to submit a New Drug Application (NDA) to the FDA by the second half of 2026.

UTHR Stock Price Activity: United Therapeutics shares were up 16.5% at $608.84 during premarket trading on Monday, according to Benzinga Pro data.

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