Tyvaso Improves Exercise Capacity of PH Patients in Group 3 WHO Classification, Data Show

Tyvaso (inhaled treprostinil) significantly improved the exercise capacity of people with World Health Organization (WHO) Group 3 pulmonary hypertension associated with interstitial lung disease (PH-ILD), achieving its primary endpoint in the Phase 3 INCREASE study, announced the treatment’s developer, United Therapeutics.

Study findings were recently described in an online presentation, titled “Inhaled Treprostinil in Interstitial Lung Disease Associated Pulmonary Hypertension: The INCREASE Study,” at a Breaking News Session hosted by the American Thoracic Society.

WHO Group 3 patients have pulmonary hypertension resulting from lung diseases or a shortage of oxygen (hypoxia). PH-ILD is caused by scarring (fibrosis) of the lungs resulting in stiffness, which makes it difficult to breathe. 

INCREASE is a randomized, placebo-controlled parallel group study (NCT02630316) designed to evaluate Tyvaso’s impact on PH-ILD patients’ exercise capacity as analyzed by the six-minute walk distance (6MWD) test — the distance an individual can walk in six minutes — after 16 weeks of treatment.

A total of 326 PH-ILD patients were enrolled in the trial. Half received inhaled Tyvaso and the other half a placebo, four times daily.

After 16 weeks of treatment, patients given Tyvaso had a mean increase of 21 meters (69 feet) in 6MWD compared to those on the placebo.

Significant improvements were also found in the study’s secondary endpoints, including a reduction in the cardiac function biomarker NT-proBNP (meaning less heart strain), and an increase in the time to the first clinical worsening event.

These positive effects were seen across several subgroups in the trial, including subgroups based on different PH-ILD causes, disease severity, gender, or age.

Data also showed that Tyvaso treatment — inhaled four times daily, up to a maximum of 12 breaths per session — was well-tolerated, consistent with previous Tyvaso studies.

According to United Therapeutics, additional study results will be made available in upcoming peer-reviewed publications, including data on additional exploratory objectives of the trial, such as changes in quality of life and distance saturation product — which assesses blood oxygen levels during the 6MWD test. Analysis of biomarkers and patient genomics will also be performed. 

United Therapeutics recently submitted a supplemental new drug application to the U.S. Food and Drug Administration, seeking to revise Tyvaso’s label to reflect the outcome of the INCREASE study.

Tyvaso is currently approved for the treatment of WHO Group 1 pulmonary arterial hypertension patients to improve exercise capacity.

The active component of the therapy is a molecule that mimics the action of prostacyclin, which is naturally produced by the body to dilate blood vessels. Prostacyclin binds to receptors on cells of the arterial walls, causing muscles to relax and making it easier for blood to be pumped through the lungs. Prostacyclin also stops platelets from clumping together and potentially blocking arteries.