Study of Efficacy and Safety of Inhaled Treprostinil in Subjects With Idiopathic Pulmonary Fibrosis

Phase 3 Completed 598 enrolled United Therapeutics

RandomizedParallel-groupQuadruple-blindTreatment

Summary

Study RIN-PF-301 is designed to evaluate the superiority of inhaled treprostinil against placebo for the change in absolute forced vital capacity (FVC) from baseline to Week 52.

Timeline

Start: 2021-06-01
Primary completion: 2026-02-02
Completion: 2026-02-02

Outcome

Met primary endpoint

paper with treprostinil and -196.2 ml (95% CI, -227.1 to -155.6) with placebo (difference, 130.1 ml; 95% CI, 82.2 to 178.1; P<0.001). PMID 42149993 ↗

paper In patients with IPF, treatment with inhaled treprostinil led to a smaller decline in FVC PMID 42149993 ↗

release “TETON-1 met its primary efficacy endpoint, with nebulized Tyvaso demonstrating statistically significant improvement in absolute FVC relative to placebo” unither.com ↗

Publications

Nathan SD, Smith P, Deng C, King CS, De Salvo M, Weigt SS, Pandya S, Bandyopadhyay D, Lasky JA, Krishna R, Hambly N, Ramaswamy M, Kebbe J, Ettinger N, Gao J, Rao Y, Breytenbach N, Peterson L, Bell H, Behr J, Cottin V, Flaherty KR; TETON-1 Trial Investigators. Phase 3 Trials of Inhaled Treprostinil for Idiopathic Pulmonary Fibrosis. N Engl J Med. 2026 Jul 9;395(2):115-126. doi: 10.1056/NEJMoa2501488. Epub 2026 May 18.

Drugs

Evaluation	Drug	Modality	Dose	Route
Subject	Treprostinil	Other / unclassified	72 ug	Inhaled