If cleared by federal regulators, nebulized Tyvaso (treprostinil) Inhalation Solution would become the first inhaled option designed to treat idiopathic pulmonary fibrosis (IPF).
RT’s Three Key Takeaways:
- Regulatory Review: The FDA has accepted a supplemental New Drug Application (sNDA) for nebulized Tyvaso (treprostinil) Inhalation Solution to treat idiopathic pulmonary fibrosis (IPF), with an anticipated decision date in late April 2027.
- Primary Endpoint Success: In combined analyses of two phase 3 registration trials, nebulized Tyvaso demonstrated a statistically significant 111.8 mL improvement in absolute forced vital capacity compared with placebo over 52 weeks in patients receiving standard background therapy, the company reported.
- Secondary Outcome Benefits: Trial data showed that the therapy achieved statistical significance for key secondary measures, including lowering the risk of clinical worsening events, reducing acute disease exacerbations, and improving patient-reported quality of life.
The FDA has accepted an sNDA for nebulized Tyvaso (treprostinil) Inhalation Solution for the treatment of IPF, according to United Therapeutics Corp. The company stated that it anticipates the agency will complete its review in late April 2027. If approved, nebulized Tyvaso will be the first and only inhaled anti-fibrotic therapy for IPF in the US, where it currently remains investigational.
“Nebulized Tyvaso combines direct lung delivery with multimodal activity across fibrotic, vascular, and inflammatory pathways that are central to IPF, with the potential to help address a significant unmet need for this life-threatening disease,” said Martine Rothblatt, PhD, chairperson and chief executive officer of United Therapeutics, in a news release. “We’re galvanized by the FDA’s acceptance of the nebulized Tyvaso sNDA for review and believe the strength and rigor of our TETON clinical program support an approvable application for this differentiated multi-pathway treatment for patients managing this life-threatening disease.”
Phase 3 TETON Clinical Results
According to United Therapeutics, the regulatory submission was based on results from the phase 3 TETON-1 and TETON-2 registration studies, which evaluated the safety and efficacy of nebulized Tyvaso in patients with IPF over 52 weeks. The multicenter, randomized, double-blind, placebo-controlled trials enrolled distinct patient cohorts, with TETON-1 conducted in the US and Canada, and TETON-2 conducted internationally outside the US and Canada.
In combined analyses across both trials, nebulized Tyvaso met the primary efficacy endpoint, demonstrating statistically significant superiority over placebo in the change in absolute forced vital capacity (FVC) by 111.8 mL (Hodges-Lehmann estimate; 95% confidence interval, 79.7 to 144.0 mL; P < .0001) from baseline to week 52 in an IPF population broadly receiving background therapy, the company reported.
Secondary Endpoints and Safety Data
Combined trial findings also showed that nebulized Tyvaso achieved statistical significance for most key secondary endpoints, according to data presented at the 2026 American Thoracic Society (ATS) annual meeting and published in The New England Journal of Medicine. These included a reduced risk of a clinical worsening event, a reduced risk of an acute IPF exacerbation, and improvements in percent of predicted FVC, the King’s Brief Interstitial Lung Disease (K-BILD) quality of life questionnaire, and diffusion capacity of lungs for carbon monoxide (DLCO).
Safety monitoring throughout the trials evaluated adverse events, serious adverse events, vital signs, clinical laboratory parameters, and electrocardiogram parameters, according to the manufacturer. Participants who completed either trial were eligible to enroll in TETON-OLE, an ongoing open-label extension study assessing long-term safety and tolerability in patients with fibrotic lung disease.
Investigational Status and Program Background
According to United Therapeutics, the TETON clinical program was established after a post-hoc analysis of the INCREASE study in patients with pulmonary hypertension associated with interstitial lung disease (PH-ILD) indicated that nebulized Tyvaso was associated with a significant improvement in FVC. The company has also completed patient enrollment in TETON-PPF, a global study evaluating nebulized Tyvaso in progressive pulmonary fibrosis (PPF).
Both the FDA and the European Medicines Agency have granted orphan designation for treprostinil to treat IPF, according to the company. United Therapeutics emphasized that nebulized Tyvaso has not received FDA approval for IPF or PPF and remains investigational for both indications.
