With a second phase 3 win for Tyvaso in idiopathic pulmonary fibrosis (IPF), United Therapeutics is padding the case for an expansion and putting more color on its filing plans with the FDA.
In the wake of the “overwhelmingly positive” pair of late-stage readouts, multiple analysts are sharing in United’s optimism that Tyvaso (treprostinil) could change the treatment landscape in the lung scarring disease, which is estimated to affect more than 100,000 people in the U.S.
In the late-stage TETON-1 trial, nebulized Tyvaso bested placebo on changes in forced vital capacity (FVC)—measuring the amount of air a patient can forcefully exhale after a deep breath—from baseline to the study’s one-year mark. This allowed the study to meet its primary efficacy endpoint and comes after another positive readout for Tyvaso in IPF in the TETON-2 study late last summer, United Therapeutics said Monday.
United’s drug won out on multiple fronts in the topline showing from TETON-1, demonstrating benefits across “all subgroups” of patients, regardless of smoking status and including those who used background therapy or supplemental oxygen, the company said in its release.
Moreover, the inhaled prostacyclin analog also hit statistical significance when it came to curbing the risk of clinical worsening and showed numerical improvements in other endpoints versus placebo—such as time to first acute IPF exacerbation and scoring on a lung disease quality-of-life questionnaire.
Multiple analysts were enthusiastic about the news, with the team at Jefferies writing in a March 30 note that the topline readout from TETON-1 “hits even better than TETON-2” and supports a “new IPF standard.”
The sentiment was much the same from the team at Leerink Partners, which opined that the “best-case data” from Tyvaso’s latest phase 3 trial positions the drug to escape competitor dynamics in its inaugural pulmonary arterial hypertension indication for the “more ‘green field’ blockbuster opportunity of idiopathic pulmonary fibrosis.”
The Jefferies team suggested that Tyvaso could be looking at a potential $5 billion to $10 billion opportunity in IPF as a mounting body of evidence positions the drug to become “part of [the] future standard of care,” either alone or as part of a combination therapy.
The analysts added that the TETON-1 data, on top of the earlier results from TETON-2, confirm that the prior study readout was not a “one-off,” suggesting that it “reinforces a reproducible magnitude that is competitive in the modern IPF landscape.”
Investors seem to be responding well to the data drop, too: United Therapeutics’ stock was trading up some 13% as of 2:30 p.m. EDT on Monday, March 30.
Looking at the two late-stage wins together via an integrated analysis, United noted that Tyvaso demonstrated statistical significance over placebo on the change in FVC endpoint, plus “most secondary endpoints” at the 52-week mark, adding that overall survival at one year trended in favor of its drug but fell short of statistical significance.
Now, United says it plans to seek FDA priority review for Tyvaso in IPF by the end of the summer. Both the U.S. FDA and the European Medicines Agency have blessed Tyvaso with orphan drug designation in the indication.
IPF is a scarring disease of the lungs, the cause of which is unknown. It constitutes the most common of the idiopathic interstitial pneumonias and is characterized by the progressive loss of the lungs’ ability to transfer oxygen to the blood, which ultimately leads to respiratory failure and death.
The condition rarely manifests before the age of 50 and can be associated with cigarette smoking and “certain genetic dispositions,” according to United.
Tyvaso, for its part, was initially approved back in 2009 to treat pulmonary arterial hypertension. In more recent years, the drug has extended its staying power in the indication with green lights for a new formulation and delivery device, plus a nod to treat PAH associated with interstitial lung disease.
Reflecting on the latest IPF data, the team at Leerink said they are confident that Tyvaso could represent the “‘next contender’” in the indication and suggested that the strong showing from United’s drug could open the window for “greater clinician enthusiasm around new mechanism entrants to the IPF space overall.”
In the IPF treatment landscape, Boehringer Ingelheim recently scored a U.S. green light with last October’s FDA nod for its PDE4 inhibitor Jascayd, which represented the first new IPF approval in more than a decade. Boehringer’s own Ofev and Roche’s Esbriet form the remaining backbone of IPF treatment in the U.S., with both of those drugs scoring approvals in 2014.