TETON-2, a placebo-controlled phase 3 study, demonstrated that inhaled treprostinil (Tyvaso) significantly slowed the decline in lung function in patients with idiopathic pulmonary fibrosis (IPF).[1][2] The primary study objective was met: Tyvaso improved absolute forced vital capacity (FVC) by 95.6 mL versus placebo (Hodges-Lehmann estimate, p < 0.0001) from baseline to week 52.[1][3] The study included 597 adult patients over the age of 40 with IPF who received Tyvaso or placebo daily by inhalation through a nebulizer.[2] Tyvaso benefits were seen across all subgroups, including use of adjunctive therapy (nintedanib, pirfenidone, or none), smoking, and oxygen use.[1] Time to first acute exacerbation of IPF and overall survival at week 52 were not statistically significant but trended in favor of Tyvaso.[1] Tyvaso treatment was well tolerated, with a safety profile consistent with previous studies and known adverse effects of prostacyclin, with no new safety signals.[1][2] United Therapeutics plans to use the results from TETON-2 and another TETON study to apply for approval of Tyvaso for IPF.[2]