CI

At a glance

ClinicalIndex Comparison Record
Phase 3Completed· 168 enrolled
Drug / intervention
Frespaciguat +1 moredrug
Likely dose
Frespaciguat 380 µgfrom record
Structured eligibility isn't available for this trial yet — see the full criteria in the Eligibility tab below.

Standardized by ClinicalIndex from the ClinicalTrials.gov record · verify against the source.

Search/NCT04732221
NCT04732221Phase 3Completed

A Phase 2/3, Multicenter, Randomized, Double-blind, Placebo-Controlled, Adaptive Design Study to Evaluate the Efficacy and Safety of MK-5475 in Adults With Pulmonary Arterial Hypertension

Merck Sharp & Dohme LLC·interventional·Posted Feb 1, 2021·Updated May 25, 2025

In Brief

A Phase 3 clinical trial evaluating Frespaciguat and Placebo to Frespaciguat for Pulmonary Arterial Hypertension and Hypertension, Pulmonary. Completed, enrolled 168 participants across 91 sites in 18 countries.

Detailed Summary

This is a two-part (Phase 2/Phase 3) study of frespaciguat, an inhaled soluble guanylate cyclase stimulator, in participants with pulmonary arterial hypertension (PAH). The first part (Phase 2) will assess three different doses of frespaciguat compared to placebo in a base period of 12 weeks, followed by comparison of three different doses of frespaciguat during an optional 40 month extension period. The treatment dose with the best efficacy and safety profile in the phase 2 cohort base period will be selected for use in the second part (Phase 3) of the study. The primary hypothesis of Phase 2 is that at least one frespaciguat dose is superior to placebo in reducing pulmonary vascular resistance (PVR) from baseline at week 12. The purpose of the second part (Phase 3) of the study is to confirm the efficacy, safety, and tolerability of frespaciguat at the selected dose compared to placebo during a 12 week base period followed by an extension period of up to 5 years. The primary hypothesis of Phase 3 is that frespaciguat is superior to placebo in increasing 6-minute walk distance (6MWD) from baseline at week 12. Due to sponsor's decision this phase/part was not conducted.

Study Details

Study Typeinterventional
Allocation--
Masking--
Primary Purpose--
CountriesArgentina, Australia, Belgium, Canada, Colombia, France, Germany, Greece, Israel, Italy, Mexico, New Zealand, Poland, Russia, Sweden, Turkey (Türkiye), United Kingdom, United States
Collaborators--

Timeline

Phase 3CompletedFinished
202120222023202420252026
First PostedFeb 1, 2021
Enrollment StartMay 19, 2021
Primary CompletionJan 4, 2024
Study CompletionJul 2, 2024
TodayJul 2, 2026
Enrollment to primary: 2.6 yearsPosted 5.4 years ago

Interventions

Frespaciguatdrug

Frespaciguat (soluble guanylate cyclase stimulator) 380 µg, 100 µg or 32 µg administered as dry powder inhalation

Placebo to Frespaciguatdrug

Placebo administered as dry powder inhalation