Results from an ongoing study show once-daily treprostinil palmitil inhalation powder improves exercise capacity and reduces mortality risk status for patients.
RT’s Three Key Takeaways:
- Sustained Efficacy: Patients using treprostinil palmitil inhalation powder (TPIP) showed continued improvement in walk distance and functional class over 12 months of treatment.
- Mortality Risk: The study demonstrated a meaningful reduction in mortality risk scores, with approximately 65% of participants reaching a refined low-risk status.
- Safety Profile: Once-daily administration of the inhalation powder was generally well tolerated with no new safety signals reported at doses up to 1,280 µg.
Insmed Inc announced positive 12-month data from an ongoing open-label extension (OLE) study evaluating treprostinil palmitil inhalation powder (TPIP) in patients with pulmonary arterial hypertension (PAH), according to the company.
The OLE study is a non-placebo-controlled trial designed to assess the long-term safety and effectiveness of the once-daily inhaled therapy. The data demonstrated sustained improvements across all secondary efficacy measures, including six-minute walk distance (6MWD), N-terminal fragment pro-B-type natriuretic peptide (NT-proBNP) concentration, and World Health Organization (WHO) functional class.
“These data from our ongoing OLE study with TPIP represent an important milestone in our efforts to fully harness the potential of treprostinil and provide meaningful benefit to patients with pulmonary arterial hypertension,” said Gene Sullivan, MD, chief product strategy officer of Insmed, in a news release.
According to the 12-month results, the mean improvement in 6MWD from baseline was 55.7 meters for patients who continued TPIP and 54.1 meters for those who crossed over from the placebo group. NT-proBNP concentrations were reduced by approximately 60% in both groups. Additionally, WHO functional class I or II was achieved by 78.3% of the continuous TPIP group and 80.6% of the group that switched from placebo.
The study also tracked patient trajectory using the REVEAL Lite 2.0 risk score, a non-invasive tool that estimates mortality risk. Patients in the continuous TPIP group saw an average 2.0-point improvement from baseline. Approximately 65% of all patients achieved a refined low-risk status, which is associated with a less than 5% estimated risk of mortality at three years.
“The REVEAL Lite 2.0 risk score provides a powerful, non-invasive way to track disease trajectory,” said Raymond Benza, MD, phase 2b PAH study steering committee member, in a news release. “Here we saw that patients on TPIP averaged a greater than 1-point improvement from baseline, which is really meaningful for patients. Sustained improvements of this magnitude, alongside gains in exercise capacity and Functional Class, provide a strong clinical rationale to advance this therapy into Phase 3 development.”
Regarding safety and tolerability, the news release stated that once-daily TPIP was generally well tolerated with no newly identified safety signals at doses up to 1,280 µg through month 12. Treatment-emergent adverse events (TEAEs) occurred in 89.0% of patients, while serious TEAEs were observed in 18.7% of the study population.
The most common adverse events occurring in 5.0% or more of patients included headache, cough, nasopharyngitis, diarrhea, and upper respiratory tract infection. Adverse events led to study discontinuation in 7.7% of patients. Four deaths occurred during the study, though none were considered related to the TPIP treatment, according to the company.
The 12-month findings support the recent initiation of PALM-PAH, a phase 3 randomized, double-blind, placebo-controlled trial evaluating once-daily TPIP in patients with PAH over 24 weeks. The primary endpoint for the phase 3 study will be the change in 6MWD, with additional assessments of safety and overall healthcare outcomes.
