United Therapeutics (NASDAQ:UTHR), a public benefit corporation, today announced that its pivotal TETON-1 study evaluating nebulized Tyvaso® (treprostinil) for the treatment of idiopathic pulmonary fibrosis (IPF) met its primary efficacy endpoint.
The study demonstrated a statistically significant improvement in absolute forced vital capacity (FVC) compared to placebo, marking a major milestone for a disease characterized by progressive, irreversible lung scarring.
In the 598-patient randomized Phase 3 study, nebulized Tyvaso showed a 130.1 mL superiority over placebo in the change of absolute FVC from baseline to week 52 (p < 0.0001).
These results were further strengthened by an integrated analysis of the TETON-1 and TETON-2 studies, which showed a combined treatment effect of 111.8 mL (p<0.0001).
The efficacy was consistent across all patient subgroups, including those already on background anti-fibrotic therapies such as nintedanib or pirfenidone.
Beyond the primary endpoint, Tyvaso achieved statistical significance in reducing the risk of clinical worsening and showed numerical improvements in several key secondary metrics.
These included the time to first acute exacerbation of IPF, quality of life scores measured by the K-BILD questionnaire, and carbon monoxide diffusion capacity (DLCO).
While overall survival at week 52 trended in favor of the Tyvaso group, it did not reach statistical significance at this stage.
Meanwhile, the safety profile of nebulized Tyvaso remained consistent with previous studies, with no new safety signals identified.
Common adverse events were primarily related to known prostacyclin effects, and the treatment was generally well-tolerated over the 52-week period.
United Therapeutics plans to submit a supplemental New Drug Application (sNDA) to the U.S. Food and Drug Administration (FDA) by the end of this summer, seeking to expand Tyvaso's label to include IPF.
The company also intends to seek priority review for the application.
If approved, Tyvaso would become the first inhaled therapy specifically indicated to improve lung function in patients with this devastating respiratory condition.