Business Wire·Oct 19, 2026, 7:00 AM ET

United Therapeutics Announces FDA Clearance to Proceed with SUMMIT Clinical Trial for Treprostinil SMI in PH-COPD

United Therapeutics received FDA clearance to proceed with the SUMMIT clinical trial for treprostinil soft mist inhaler (SMI) in patients with pulmonary hypertension associated with chronic obstructive pulmonary disease (PH-COPD).
The phase 2, 16-week, double-blind SUMMIT study will evaluate safety & tolerability in approximately 40 patients, with secondary endpoints assessing exercise capacity & NT-proBNP biomarkers.
Eligible SUMMIT participants may enroll in an open-label extension study to assess long-term safety, tolerability, & efficacy.
United Therapeutics anticipates commencing a phase 3 registration study for treprostinil SMI in PH-COPD in 2028, assuming successful SUMMIT outcomes.
Treprostinil SMI is a portable, handheld device delivering a preserved solution in a single breath, administered four times daily, with single-load cartridges supporting up to two weeks of use at room temperature.
The company aims for treprostinil SMI to become the first FDA-approved therapy specifically indicated for PH-COPD, addressing an estimated 400,000 to 800,000 U.S. patients with this condition.
United Therapeutics plans to further develop treprostinil SMI for other indications including pulmonary arterial hypertension, pulmonary hypertension associated with interstitial lung disease, idiopathic pulmonary fibrosis, & progressive pulmonary fibrosis.
Treprostinil SMI remains an investigational-stage product & is not yet approved in any jurisdiction for any indication.