A Study of the Efficacy and Safety of Frespaciguat (MK-5475) in Participants With Pulmonary Arterial Hypertension (INSIGNIA-PAH: Phase 2/3 Study of an Inhaled sGC Stimulator in PAH) (MK-5475-007)

NCT ID: NCT04732221

Last Updated: 2025-05-25

Study Results

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Basic Information

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Recruitment Status

COMPLETED

Clinical Phase

PHASE2/PHASE3

Total Enrollment

168 participants

Study Classification

INTERVENTIONAL

Study Start Date

2021-05-19

Study Completion Date

2024-07-02

Brief Summary

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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.

Detailed Description

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Conditions

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Pulmonary Arterial Hypertension Hypertension, Pulmonary

Study Design

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Allocation Method

RANDOMIZED

Intervention Model

PARALLEL

A total of approximately 450 participants will be randomized in this operationally seamless adaptive Phase 2/3 study. Phase 2 of the study will randomize approximately 164 participants into 4 arms, and Phase 3 of the study will randomize approximately 286 participants into 2 arms.
Primary Study Purpose

TREATMENT

Blinding Strategy

TRIPLE

Participants Investigators Outcome Assessors

Study Groups

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Phase 2 Cohort Frespaciguat 380 µg

Participants receive frespaciguat 380 µg via oral inhalation once daily for 12 week base period and for optional 40 month extension period.

Group Type EXPERIMENTAL

Frespaciguat

Intervention Type DRUG

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

Phase 2 Cohort Frespaciguat 100 µg

Participants receive frespaciguat 100 µg via oral inhalation once daily for 12 week base period and for optional 40 month extension period.

Group Type EXPERIMENTAL

Frespaciguat

Intervention Type DRUG

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

Phase 2 Cohort Frespaciguat 32 µg

Participants receive frespaciguat 32 µg via oral inhalation once daily for 12 week base period and for optional 40 month extension period.

Group Type EXPERIMENTAL

Frespaciguat

Intervention Type DRUG

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

Phase 2 Cohort Placebo

Participants receive placebo via oral inhalation once daily for 12 week base period, and one of the MK-5475 doses (380, 100, or 32 µg) for the optional 40 month extension period.

Group Type PLACEBO_COMPARATOR

Placebo to Frespaciguat

Intervention Type DRUG

Placebo administered as dry powder inhalation

Phase 3 Cohort Frespaciguat

Participants receive one of 3 frespaciguat doses (380, 100 or 32 µg) to be selected at end of the Phase 2 Cohort, administered via oral inhalation once daily for 12-week base period and up to 40 months in the extension period

Group Type EXPERIMENTAL

Frespaciguat

Intervention Type DRUG

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

Phase 3 Cohort Placebo

Participants receive placebo via oral inhalation once daily for 12 week base period and up to 40 months in the extension period.

Group Type PLACEBO_COMPARATOR

Placebo to Frespaciguat

Intervention Type DRUG

Placebo administered as dry powder inhalation

Interventions

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Frespaciguat

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

Intervention Type DRUG

Placebo to Frespaciguat

Placebo administered as dry powder inhalation

Intervention Type DRUG

Eligibility Criteria

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Inclusion Criteria

* Pulmonary arterial hypertension (PAH) in one of the following groups:

* Idiopathic PAH
* Heritable PAH
* Drug and toxin-induced PAH
* PAH associated with connective tissue disease, HIV infection, or congenital heart disease.
* Diagnosis of PAH documented by right heart catheterization (RHC).
* Eligibility RHC meeting all of the following criteria:

* Mean pulmonary artery pressure (mPAP) ≥25 mmHg
* Pulmonary vascular resistance (PVR) of ≥3 Wood units
* Pulmonary capillary wedge pressure (PCWP) or left ventricular end diastolic pressure (LVEDP) ≤15 mmHg.
* World Health Organization functional class (WHO-FC) symptoms between Class II and IV.
* Two 6-Minute walk distance (6MWD) measurements between 150 and 500 meters, one at screening and one at randomization.
* Stable concomitant background PAH-specific therapy.
* Body Mass Index (BMI) between 18.5 kg/m² and 40 kg/m² .
* Agree to be abstinent from heterosexual intercourse or use contraception during the intervention period and for at least 14 days after the last dose of study intervention.
* Female participants may not be pregnant or breastfeeding.

Exclusion Criteria

* Group 2 to 5 pulmonary hypertension.
* PAH in one of the following groups:

* Long term responders to calcium channel blockers
* Overt features of venous/capillary involvement
* Evidence of more-than-mild obstructive lung disease.
* Evidence of more-than-mild parenchymal lung disease.
* Evidence of more-than-mild obstructive sleep apnea (OSA) that is untreated.
* Evidence or history of left heart disease, including any of the following:

* Left ventricular ejection fraction (LVEF) ≤45%
* Moderate or severe left-sided valvular disease (aortic or mitral valve stenosis or regurgitation)
* Significant left ventricular diastolic dysfunction on echocardiographic evaluation
* Presence of 3 or more of the following risk factors for heart failure with preserved ejection fraction: BMI\>30 kg/m², essential systemic hypertension, diabetes mellitus of any type, or coronary artery disease.
* Oxygen saturation measured by pulse oximetry (SpO₂) \<90%, despite supplemental oxygen therapy.
* Chronic renal insufficiency (eGFR \<30 mL/min)
* Chronic liver disease (i.e., Child-Pugh B or C), portal hypertension, cirrhosis, or significant hepatic laboratory abnormalities.
* Current smoker or currently uses electronic cigarettes (vapes).
* History of cancer, except: nonmelanomatous skin carcinoma or carcinoma in situ of the cervix or other malignancies which have been successfully treated, with appropriate follow up, and unlikely to recur for the duration of the study.
Minimum Eligible Age

18 Years

Maximum Eligible Age

75 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

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Merck Sharp & Dohme LLC

INDUSTRY

Sponsor Role lead

Responsible Party

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Responsibility Role SPONSOR

Principal Investigators

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Medical Director

Role: STUDY_DIRECTOR

Merck Sharp & Dohme LLC

Locations

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University of California San Diego Health-Pulmonary Critical Care ( Site 0061)

La Jolla, California, United States

Site Status

University of California Davis Health-Internal Medicine: Pulmonary, Critical Care and Sleep Medicine

Sacramento, California, United States

Site Status

UCSF Helen Diller Medical Center at Parnassus Heights ( Site 0063)

San Francisco, California, United States

Site Status

University of Colorado - Denver ( Site 0003)

Aurora, Colorado, United States

Site Status

Cardiovascular Institute of North Colorado - Banner Health ( Site 0013)

Greeley, Colorado, United States

Site Status

Georgetown University Hospital ( Site 0025)

Washington D.C., District of Columbia, United States

Site Status

University of Miami Hospital-Division of Pulmonary & Critical Care ( Site 0053)

Miami, Florida, United States

Site Status

AdventHealth Orlando ( Site 0040)

Orlando, Florida, United States

Site Status

Tampa General Hospital ( Site 0058)

Tampa, Florida, United States

Site Status

Indiana University Health Methodist Hospital ( Site 0045)

Indianapolis, Indiana, United States

Site Status

University of Iowa Hospital and Clinics ( Site 0009)

Iowa City, Iowa, United States

Site Status

University of Kansas Medical Center ( Site 0038)

Kansas City, Kansas, United States

Site Status

University of Kentucky ( Site 0006)

Lexington, Kentucky, United States

Site Status

Norton Pulmonary Specialists ( Site 0048)

Louisville, Kentucky, United States

Site Status

University of Maryland ( Site 0032)

Baltimore, Maryland, United States

Site Status

Washington University School of Medicine ( Site 0066)

St Louis, Missouri, United States

Site Status

University of Nebraska Medical Center ( Site 0041)

Omaha, Nebraska, United States

Site Status

University of New Mexico, Health Sciences Center ( Site 0028)

Albuquerque, New Mexico, United States

Site Status

Clinical Trials Unit at Eastowne Medical Office Building ( Site 0019)

Chapel Hill, North Carolina, United States

Site Status

AnMed Health ( Site 0033)

Anderson, South Carolina, United States

Site Status

Statcare Pulmonary Consultants ( Site 0067)

Knoxville, Tennessee, United States

Site Status

University of Texas Southwestern Medical Center at Dallas ( Site 0012)

Dallas, Texas, United States

Site Status

Houston Methodist Research Institute ( Site 0036)

Houston, Texas, United States

Site Status

The University of Texas Health Science Center at Houston ( Site 0054)

Houston, Texas, United States

Site Status

Sentara Norfolk General Hospital ( Site 0014)

Norfolk, Virginia, United States

Site Status

West Virginia University-WVU Heart and Vascular Institute ( Site 0051)

Morgantown, West Virginia, United States

Site Status

Cardiologia Palermo ( Site 0140)

Ciudad Autonoma de Buenos Aires, Buenos Aires, Argentina

Site Status

Centro Medico Capital ( Site 0131)

La Plata, Buenos Aires, Argentina

Site Status

Hospital Universitario Austral ( Site 0138)

Pilar, Buenos Aires, Argentina

Site Status

Instituto de Investigaciones Clinicas Quilmes ( Site 0141)

Quilmes, Buenos Aires, Argentina

Site Status

Hospital El Cruce Nestor Carlos Kirchner ( Site 0132)

San Juan Bautista, Buenos Aires, Argentina

Site Status

Sanatorio de la Trinidad Mitre ( Site 0130)

Buenos Aires, Buenos Aires F.D., Argentina

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Instituto Cardiovascular de Rosario ( Site 0128)

Rosario, Santa Fe Province, Argentina

Site Status

Hospital Privado Universitario de Córdoba ( Site 0137)

Córdoba, , Argentina

Site Status

Nepean Hospital ( Site 0184)

Kingswood, New South Wales, Australia

Site Status

Macquarie University ( Site 0180)

Macquarie University, New South Wales, Australia

Site Status

John Hunter Hospital ( Site 0185)

Newcastle, New South Wales, Australia

Site Status

Université Libre de Bruxelles - Hôpital Erasme ( Site 0601)

Brussels, Bruxelles-Capitale, Region de, Belgium

Site Status

UZ Leuven ( Site 0600)

Leuven, Vlaams-Brabant, Belgium

Site Status

Peter Lougheed Centre ( Site 0107)

Calgary, Alberta, Canada

Site Status

University Health Network - Toronto General Hospital ( Site 0104)

Toronto, Ontario, Canada

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IUCPQ ( Site 0111)

Québec, Quebec, Canada

Site Status

Centro Cardiovascular Colombiano Clínica Santa María ( Site 0154)

Medellín, Antioquia, Colombia

Site Status

Hospital Universitario San Ignacio ( Site 0152)

Bogotá, Bogota D.C., Colombia

Site Status

Fundacion Cardiovascular de Colombia ( Site 0155)

Piedecuesta, Santander Department, Colombia

Site Status

CHRU Brest - Hopital Cavale Blanche ( Site 0254)

Brest, Finistere, France

Site Status

CHU de Toulouse - Hopital Larrey ( Site 0258)

Toulouse, Haute-Garonne, France

Site Status

Institut Coeur Poumon - CHRU de Lille ( Site 0252)

Lille, Hauts-de-France, France

Site Status

Centre Hospitalier Universitaire de Rouen ( Site 0253)

Rouen, Seine-Maritime, France

Site Status

CHU - Hopital de Bicetre ( Site 0251)

Le Kremlin-Bicêtre, Val-de-Marne, France

Site Status

Thoraxklinik Heidelberg gGmbH am Universitaetsklinikum Heidelberg ( Site 0276)

Heidelberg, Baden-Wurttemberg, Germany

Site Status

Klinikum Würzburg Mitte-Medizinische Klinik - Schwerpunkt Pneumologie & Beatmungsmedizin ( Site 0280

Würzburg, Bavaria, Germany

Site Status

UKGM Gießen/Marburg ( Site 0279)

Giessen, Hesse, Germany

Site Status

Medizinische Hochschule Hannover ( Site 0284)

Hanover, Lower Saxony, Germany

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Uniklinikum Dresden ( Site 0283)

Dresden, Saxony, Germany

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Universitaetsklinikum Leipzig ( Site 0285)

Leipzig, Saxony, Germany

Site Status

AHEPA University General Hospital of Thessaloniki ( Site 0577)

Thessaloniki, , Greece

Site Status

Soroka Medical Center ( Site 0330)

Beersheba, , Israel

Site Status

Rambam Medical Center ( Site 0335)

Haifa, , Israel

Site Status

Wolfson Medical Center [Holon, Israel] ( Site 0333)

Holon, , Israel

Site Status

Shaare Zedek Medical Center ( Site 0331)

Jerusalem, , Israel

Site Status

Rabin Medical Center ( Site 0327)

Petah Tikva, , Israel

Site Status

University of Naples Federico II ( Site 0308)

Naples, Campania, Italy

Site Status

Azienda Ospedaliera Policlinico Umberto I ( Site 0301)

Rome, Lazio, Italy

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Ospedale San Gerardo - ASST Monza ( Site 0304)

Monza, Monza E Brianza, Italy

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Centro Cardiologico Monzino IRCCS ( Site 0306)

Milan, , Italy

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Fondazione IRCCS Policlinico San Matteo ( Site 0302)

Pavia, , Italy

Site Status

Instituto Nacional de Cardiología -Ignacio Chavez ( Site 0651)

Mexico City, Mexico City, Mexico

Site Status

Consultorio 1020 Hospital Angeles Xalapa ( Site 0654)

Xalapa, Veracruz, Mexico

Site Status

Operadora de Hospitales Angeles. S.A. de C.V. -Sucursal Lomas ( Site 0653)

Huixquilucan, , Mexico

Site Status

Christchurch Hospital ( Site 0201)

Christchurch, Canterbury, New Zealand

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Greenlane Clinical Centre ( Site 0203)

Auckland, , New Zealand

Site Status

Krakowski Szpital Specjalistyczny im. Jana Pawa II-Oddzial Kliniczny Chorob Serca i Naczyn z Pododd

Krakow, Lesser Poland Voivodeship, Poland

Site Status

Specjalistyczny Szpital im. Dr Alfreda Sokolowskiego w Walbrzychu ( Site 0351)

Wałbrzych, Lower Silesian Voivodeship, Poland

Site Status

Samodzielny Publiczny Szpital Kliniczny nr 4 w Lublinie ( Site 0352)

Lublin, Lublin Voivodeship, Poland

Site Status

Scientific Research Institute Complex Problems Cardiovascular Disease ( Site 0403)

Kemerovo, Kemerovo Oblast, Russia

Site Status

Almazov National Medical Research Centre of the Ministry of Health ( Site 0402)

Saint Petersburg, Sankt-Peterburg, Russia

Site Status

Akademiska sjukhuset ( Site 0453)

Uppsala, Uppsala County, Sweden

Site Status

Sahlgrenska Universitetssjukhuset-Cardiology Research Unit ( Site 0452)

Gothenburg, Västra Götaland County, Sweden

Site Status

Ege Universitesi Hastanesi-Cardilogy Department ( Site 0504)

Bornova, İzmir, Turkey (Türkiye)

Site Status

Hacettepe Universitesi Tip Fakultesi Hastanesi ( Site 0510)

Ankara, , Turkey (Türkiye)

Site Status

Akdeniz Uni.Tip Fakultesi Saglik Uygulama ve Arastirma Merkezi ( Site 0508)

Antalya, , Turkey (Türkiye)

Site Status

Eskisehir Osmangazi Uni. Tip Fakultesi Hastanesi ( Site 0506)

Eskişehir, , Turkey (Türkiye)

Site Status

Istanbul Uni. Kardiyoloji Enstitusu ( Site 0502)

Istanbul, , Turkey (Türkiye)

Site Status

Istanbul Universitesi Istanbul Tip Fakultesi ( Site 0509)

Istanbul, , Turkey (Türkiye)

Site Status

Marmara Universitesi Pendik Egitim ve Arastirma Hastanesi ( Site 0501)

Istanbul, , Turkey (Türkiye)

Site Status

Dokuz Eylul University Faculty of Medicine ( Site 0505)

Izmir, , Turkey (Türkiye)

Site Status

Golden Jubilee National Hospital ( Site 0556)

Glasgow, Glasgow City, United Kingdom

Site Status

Royal Brompton and Harefield NHS Trust ( Site 0553)

London, London, City of, United Kingdom

Site Status

Imperial College Healthcare NHS Trust - Hammersmith Hospital ( Site 0554)

London, London, City of, United Kingdom

Site Status

The Freeman Hosp.Newcastle upon Tyne Hosp NHS Trust ( Site 0552)

Newcastle upon Tyne, Newcastle Upon Tyne, United Kingdom

Site Status

Countries

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United States Argentina Australia Belgium Canada Colombia France Germany Greece Israel Italy Mexico New Zealand Poland Russia Sweden Turkey (Türkiye) United Kingdom

References

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Humbert M, Hassoun PM, Chin KM, Bortman G, Patel MJ, La Rosa C, Fu W, Loureiro MJ, Hoeper MM. MK-5475, an inhaled soluble guanylate cyclase stimulator, for treatment of pulmonary arterial hypertension: the INSIGNIA-PAH study. Eur Respir J. 2024 Nov 14;64(5):2401110. doi: 10.1183/13993003.01110-2024. Print 2024 Nov.

Reference Type RESULT
PMID: 39255991 (View on PubMed)

Provided Documents

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Document Type: Study Protocol and Statistical Analysis Plan

View Document

Related Links

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Other Identifiers

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MK-5475-007

Identifier Type: OTHER

Identifier Source: secondary_id

2022-500877-15-00

Identifier Type: REGISTRY

Identifier Source: secondary_id

U1111-1278-4977

Identifier Type: REGISTRY

Identifier Source: secondary_id

2020-001108-40

Identifier Type: EUDRACT_NUMBER

Identifier Source: secondary_id

5475-007

Identifier Type: -

Identifier Source: org_study_id

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