A Phase 2 interventional study of Frespaciguat and Placebo in Pulmonary Hypertension and Chronic Obstructive Pulmonary Disease, sponsored by Merck Sharp & Dohme LLC. Active, not recruiting at 85 sites in 19 countries. Open to participants aged 40 Years to 85 Years. Per ClinicalTrials.gov, last updated 2026-05-01.
Sponsored by Merck Sharp & Dohme LLC · Phase 2, Interventional, and Treatment
Researchers are looking for ways to treat pulmonary hypertension (PH) caused by chronic obstructive pulmonary disease (COPD). The goal of the study is to learn if people who take frespaciguat can walk farther in 6 minutes at Week 24 compared to people who take placebo.
1,105 studies on the registry are indexed under Hypertension, Pulmonary; 234 are open to participants now.
This study's enrollment of 129 is above the median of 35 across 649 interventional studies indexed under Hypertension, Pulmonary.
Browse Hypertension, Pulmonary studies →Merck Sharp & Dohme LLC is the lead sponsor of 2,114 studies on the registry; 133 are open to participants now.
Of its 489 completed or terminated interventional studies of FDA-regulated products, 362 (74%) have results posted.
Counted across the registry records on this site, refreshed daily.
The key inclusion and exclusion criteria include but are not limited to the following:
Inclusion Criteria:
Exclusion criteria:
Participants with PH-COPD will receive 380 µg of frespaciguat as an oral inhalation once daily for 24 weeks (base period) and thereafter for up to 42 months (optional extension period).
Drug: Frespaciguat
Participants with PH-COPD will receive matching placebo as an oral inhalation once daily for 24 weeks (base period) and then 380 µg of frespaciguat as an oral inhalation once daily for up to 42 months (optional extension period).
Drug: Frespaciguat · Drug: Placebo
Frespaciguat 380 µg administered as dry powder inhalation once daily.
Also known as: MK-5475
Placebo administered as dry powder inhalation once daily.
Mean Change From Baseline in 6-minute Walk Distance (6MWD) at Week 24
6MWD is assessed using the 6-minute walk test (6MWT).
Time frame: Baseline and Week 24
Mean Change From Baseline in 6MWD at Week 12
6MWD is assessed using the 6-minute walk test (6MWT).
Time frame: Baseline and Week 12
Mean Change From Baseline in N-Terminal Pro B-Type Natriuretic Peptide (NT-proBNP) at Week 12
NT-proBNP was measured at baseline and Week 12.
Time frame: Baseline and Week 12
Mean Change From Baseline in NT-ProBNP at Week 24
NT-proBNP was measured at baseline and Week 24
Time frame: Baseline and Week 24
Percentage of Participants Whose World Health Organization-Functional Class (WHO-FC) Does not Worsen Relative to Baseline at Week 12
Participants are assigned one of four WHO-FC, dependent on limits of physical activity. As WHO-FC increases from I to IV, limits of physical activity increase.
Time frame: Baseline and Week 12
Percentage of Participants Whose WHO-FC Does not Worsen Relative to Baseline at Week 24
Participants are assigned one of four WHO-FC, dependent on limits of physical activity. As WHO-FC increases from I to IV, limits of physical activity increase.
Time frame: Baseline and Week 24
Percentage of Participants With One or More Adverse Events (AEs)
An adverse event (AE) is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention.
Time frame: Up to Week 206
Percentage of Participants who Discontinued Study Treatment due to an AE
An adverse event (AE) is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention. The percentage of participants who discontinue study treatment due to an AE will be presented.
Time frame: Up to Week 204
Plan to share: Yes — https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf
This study is active, not recruiting, as verified in Apr 2026. You cannot join it, but the record below documents what was studied.
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Merck Sharp & Dohme LLC