With Tivaso’s second Phase 3 victory in idiopathic pulmonary fibrosis (IPF), United Therapeutics is inflating its expansion lawsuit and adding more color to its plans to file with the FDA.
After a series of “overwhelmingly positive” late-stage results, several analysts echo United’s optimism that Tivaso (treprostinil) has the potential to change the treatment landscape for the lung scarring disease, which is estimated to affect more than 100,000 people in the United States.
In the late-stage TETON-1 trial, nebulized Tivaso outperformed a placebo in terms of change in forced vital capacity (FVC, a measure of the amount of air a patient can force out after taking a deep breath) from baseline to one year into the study. This enabled the study to meet its primary efficacy endpoint, United Therapeutics announced Monday, following new positive results for Tivaso in IPF in the TETON-2 study late last summer.
United’s drug won on multiple fronts for TETON-1’s top line, showing efficacy across “all subgroups” of patients, regardless of smoking status and even those on background therapy or supplemental oxygen, the company said in a release.
In addition, inhaled prostacyclin analogs also showed statistical significance in reducing the risk of clinical worsening, and showed numerical improvements in other endpoints compared to placebo, including time to first acute IPF exacerbation and Lung Disease Quality of Life Questionnaire scores.
Multiple analysts were enthusiastic about the news, with the Jeffries team writing in a March 30 note that top-line measurements from TETON-1 are “even better than TETON-2” and support “the new IPF standard.”
The Leerink Partners team agreed, saying the “best-case data” from Tivaso’s latest Phase 3 trial could allow the drug to avoid competitors in its first pulmonary arterial hypertension indication and capture “a more ‘greenfield’ blockbuster opportunity than in idiopathic pulmonary fibrosis.”
The Jefferies team suggested that Tivaso may be considering a potential $5 billion to $10 billion opportunity in IPF, as there is growing evidence that the drug will become “part of future standard of care” either alone or as part of a combination therapy.
Analysts added that the TETON-1 data, in addition to previous results from TETON-2, confirm that the previous findings are not a “one-off” and suggest it “strengthens competitive and reproducible scale in the modern IPF environment.”
Investors also appear to be reacting well to the data decline, with United Therapeutics stock up about 13% as of 2:30 p.m. EDT on Monday, March 30th.
Looking at the two late-stage wins together through a combined analysis, United noted that Tivaso demonstrated statistical significance versus placebo in the change in FVC endpoint and “most secondary endpoints” at 52 weeks, adding that overall survival at one year trended in favor of the drug but fell short of statistical significance.
United Airlines now says it plans to ask the FDA for priority IPF review of Tivaso by the end of the summer. Both the US FDA and the European Medicines Agency have congratulated Tivaso on orphan drug designation for the indication.
IPF is a scarring disease of the lungs whose cause is unknown. This is the most common type of idiopathic interstitial pneumonia and is characterized by a gradual loss of the lungs’ ability to carry oxygen to the blood, eventually leading to respiratory failure and death.
United Airlines says the condition rarely occurs in people under the age of 50 and may be linked to smoking and “certain genetic predispositions.”
Tivaso was first approved in 2009 for the treatment of pulmonary arterial hypertension. In recent years, the drug has expanded its staying power in indications, with new formulations and delivery devices being greenlit, as well as approval for the treatment of PAH associated with interstitial lung disease.
Reflecting on the latest IPF data, Leerink’s team said it believed Tivaso could be the “next candidate” in the indication, and suggested that United’s drug’s strong performance could “further increase clinician enthusiasm for novel mechanistic entrants across the IPF space.”
In the field of IPF treatment, Boehringer Ingelheim received FDA approval and green light in the US for its PDE4 inhibitor Jascayd last October. This is the first new IPF approval in over 10 years. Boehringer’s Ofev and Roche’s Esbrier form the remaining backbone of IPF treatment in the United States, with both drugs gaining approval in 2014.
