A Study of Sotatercept in Japanese Pulmonary Arterial Hypertension (PAH) Participants (MK-7962-020)

A Phase 3 Non-randomized, Non-controlled, Open Label Clinical Study to Evaluate the Efficacy and Safety of MK-7962 (Sotatercept) add-on to Background Therapy in Japanese Participants With Pulmonary Arterial Hypertension (PAH)

This local Phase 3 study is planned to confirm the efficacy and safety in Japanese PAH participants. The primary population of this study is Japanese PAH participants with World Health Organization Functional Class (WHO FC) II or III while the study includes PAH participants with WHO FC I or IV as other populations. There are no hypotheses for this study.

Study Overview

• Status: Completed
• Conditions: Pulmonary Arterial Hypertension
• Intervention / Treatment: Biological: Sotatercept

• Study Type: Interventional
• Enrollment (Actual): 46
• Phase: Phase 3

Contacts and Locations

Study Locations

• Japan
  • Chiba, Japan, 260-8677
    • Chiba University Hospital ( Site 2003)
  • Fukuoka, Japan, 812-8582
    • Kyushu University Hospital ( Site 2015)
  • Okayama, Japan, 701-1192
    • National Hospital Organization Okayama Medical Center ( Site 2013)
  • Tokyo, Japan, 108-8329
    • International University of Health and Welfare Mita Hospital ( Site 2008)
  • Tokyo, Japan, 1608582
    • Keio university hospital ( Site 2007)
  • Aichi-ken
    • Nagoya, Aichi-ken, Japan, 466-8560
      • Nagoya University Hospital ( Site 2010)
  • Chiba
    • Narashino, Chiba, Japan, 275-8580
      • Chiba Saiseikai Narashino hospital ( Site 2004)
  • Fukuoka
    • Kurume, Fukuoka, Japan, 830-0011
      • Kurume University Hospital ( Site 2014)
  • Hiroshima
    • Kure, Hiroshima, Japan, 7378505
      • Kure Kyosai Hospital ( Site 2017)
  • Hokkaido
    • Sapporo, Hokkaido, Japan, 060-8543
      • Sapporo Medical University Hospital ( Site 2018)
    • Sapporo, Hokkaido, Japan, 060-8648
      • Hokkaido University Hospital ( Site 2001)
  • Hyōgo
    • Kobe, Hyōgo, Japan, 650-0017
      • Kobe University Hospital ( Site 2012)
  • Miyagi
    • Sendai, Miyagi, Japan, 980-8574
      • Tohoku University Hospital ( Site 2002)
  • Osaka
    • Suita, Osaka, Japan, 564-8565
      • National Cerebral and Cardiovascular Center ( Site 2011)
  • Shizuoka
    • Hamamatsu, Shizuoka, Japan, 431-3192
      • Hamamatsu University Hospital ( Site 2016)
  • Tokyo
    • Bunkyo-ku, Tokyo, Japan, 113-8654
      • The University of Tokyo Hospital ( Site 2006)
    • Mitaka, Tokyo, Japan, 181-8611
      • Kyorin University Hospital ( Site 2005)

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Documented diagnostic right heart catheterization (RHC) at any time prior to screening confirming the diagnosis of World Health Organization (WHO) pulmonary arterial hypertension (PAH) Group 1 in any of the following subtypes:

  • Idiopathic PAH
  • Heritable PAH
  • Drug/toxin-induced PAH
  • PAH associated with connective tissue disease
  • PAH associated with simple, congenital systemic-to-pulmonary shunts at least 1 year following repair
• PAH classified as WHO functional class (FC) I or symptomatic PAH classified as WHO FC II to IV
• On stable doses of background PAH therapy and diuretics (if applicable) for at least 90 days prior to screening

Exclusion Criteria

• Diagnosis of PH WHO Groups 2, 3, 4, or 5

• Diagnosis of the following PAH Group 1 subtypes:

  • Human immunodeficiency virus (HIV)-associated PAH
  • PAH associated with portal hypertension
  • Schistosomiasis-associated PAH
  • PAH with features of significant venous/capillary pulmonary veno-occlusive disease/pulmonary capillary hemangiomatosis (PVOD/PCH) involvement
• Is on the waiting list for lung transplant
• Pregnant or breastfeeding women
• History of full or partial pneumonectomy
• Pulmonary function test (PFT) values of forced vital capacity (FVC) < 60% predicted at the screening visit or within 6 months prior to the screening visit.
• Initiation of an exercise program for cardiopulmonary rehabilitation within 90 days prior to the screening visit or planned initiation during the study.
• History of more than mild obstructive sleep apnea that is untreated
• Known history of portal hypertension or chronic liver disease, including hepatitis B and/or hepatitis C (with evidence of recent infection and/or active virus replication), defined as mild to severe hepatic impairment.
• History of restrictive, constrictive, or congestive cardiomyopathy.
• History of atrial septostomy within 180 days prior to the screening visit.
• Personal or family history of long QT syndrome (LQTS) or sudden cardiac death.
• Left ventricular ejection fraction (LVEF) < 45% on historical Echocardiogram (ECHO) within 6 months prior to the screening visit.
• Any symptomatic coronary disease events within 6 months prior to the screening visit.
• Cerebrovascular accident within 3 months prior to the screening visit.
• Significant (≥ 2+ regurgitation) mitral regurgitation or aortic regurgitation valvular disease, mitral stenosis and more than mild aortic valve stenosis.
• Prior exposure to sotatercept or luspatercept or history of allergic or anaphylactic reaction or hypersensitivity to recombinant proteins or excipients in investigational product
• Received intravenous inotropes (e.g., dobutamine, dopamine, norepinephrine, vasopressin) within 30 days prior to the screening visit
• Currently enrolled in or have completed any other investigational product study within 30 days
• Weight at the screening is over 85 kg

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Sotatercept; Participants on background PAH therapy will receive sotatercept subcutaneous (SC) injections at a starting dose of 0.3 mg/kg with a target dose of 0.7 mg/kg every 3 weeks up to 24 weeks. Thereafter, participants may choose to receive the sotatercept treatment at same dose and schedule in the extension treatment period from Week 24 until up to 6 months after sotatercept becomes locally commercially available and reimbursed in Japan.

Biological: Sotatercept; SC injection at a starting dose of 0.3 mg/kg with a target dose of 0.7 mg/kg every 21 days plus background PAH therapy.; Other Names: ACE-011; MK-7962; ActRIIA-IgG1Fc

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change From Pulmonary Vascular Resistance (PVR) From Baseline at Week 24	PVR was the resistance against blood flow from the pulmonary artery to the left atrium. PVR was measured in dyn*sec/cm^5 by right heart catheterization (RHC). RHC was performed during the screening period (baseline) and Week 24. Per protocol, the change in PVR from baseline at Week 24 was reported for the primary treatment period.	Baseline and Week 24
Number of Participants Who Experienced an Adverse Event (AE)	An AE was any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. Per protocol, the number of participants who experienced an AE were reported for the primary treatment period.	Up to ~24 weeks
Number of Participants Who Discontinued Study Intervention Due to AEs	An AE was any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. Per protocol, the number of participants who discontinued study treatment due to AEs were reported for the primary treatment period.	Up to ~24 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change From Baseline in Six-Minute Walk Distance (6MWD) at Week 24	The 6MWD was the distance walked in 6 minutes as a measure of functional capacity was measured during the screening period (baseline) and at Week 24. This was assessed using the 6-minute walk test (6MWT). Per protocol, the change from baseline in 6MWD at Week 24 was reported for the primary treatment period.	Baseline and Week 24
Percentage of Participants With Improvement in World Health Organization Functional Class (WHO FC) at Week 24	The severity of participant's pulmonary arterial hypertension (PAH) symptoms will be graded using the WHO FC system. WHO functional classification for PAH ranges from Class I (no limitation in physical activity, no dyspnea with normal activity), Class II (slight limitation of physical activity), Class III (marked limitation of physical activity) and Class IV (cannot perform a physical activity without any symptoms, dyspnea at rest). Participants who improve in WHO FC were classified into "Improved", "No change" and "Worsened". Improvement = reduction in FC, worsened = increase in FC and no change = no change in FC. Per protocol, the percentage of participants with improvement in WHO FC at Week 24 were presented for the primary treatment period.	Baseline and Week 24
Change From Baseline in N-terminal proB-type Natriuretic Peptide (NT-proBNP) at Week 24	NT-proBNP is an established marker of ventricular dysfunction in participants with PAH. NT-proBNP was measured at Day 1 (baseline) and at Week 24. The change from baseline in NT-proBNP at Week 24 was reported for the primary treatment period.	Baseline and Week 24

Collaborators and Investigators

• Sponsor: Merck Sharp & Dohme LLC
• Investigators: Study Director: Medical Director, Merck Sharp & Dohme LLC

Publications and helpful links

General Publications

• Matsubara H, Tanabe N, Ogo T, Abe K, Inami T, Maeda Y, Arano I, Shirakawa M, Sakai R, Cornell AG; sotatercept study 020 investigators. Phase 3, Open-Label Multicenter Study of Sotatercept in Japanese Participants With Pulmonary Arterial Hypertension. JACC Asia. 2026 Jan 20:S2772-3747(25)00709-4. doi: 10.1016/j.jacasi.2025.12.009. Online ahead of print.

Helpful Links

• Merck Clinical Trials Information

Study record dates

Study Major Dates

• Study Start (Actual): May 10, 2023
• Primary Completion (Actual): March 12, 2024
• Study Completion (Actual): November 6, 2025

Study Registration Dates

• First Submitted: April 5, 2023
• First Submitted That Met QC Criteria: April 5, 2023
• First Posted (Actual): April 18, 2023

Study Record Updates

• Last Update Posted (Actual): March 3, 2026
• Last Update Submitted That Met QC Criteria: February 10, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Lung Diseases; Hypertension, Pulmonary; Pulmonary Arterial Hypertension; ACE-011
• Other Study ID Numbers: 7962-020; jRCT2031230046 (Registry Identifier: jRCT); MK-7962-020 (Other Identifier: MSD)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: Yes