Overview
Sponsor-declared trial summary
Pulmonary Arterial Hypertension (PAH)
To evaluate the long-term safety and tolerability of sotatercept.
Key facts
- Sponsor
- Merck Sharp & Dohme LLC
- Participant type
- Patients
- Age range
- 18-64 years, 65+ years
- Gender
- Male and Female
- Therapeutic area
- Diseases [C] - Cardiovascular Diseases [C14]
- Trial duration
- 19 Dec 2025 → ongoing
- Decision date (initial)
- 2025-12-05
- Transition trial
- No
- Low-intervention
- No
- Rare-disease indication
- Yes
- Vulnerable population
- No
- Funding sources
- Merck Sharp & Dohme LLC
External identifiers
- EU CT number
- 2025-521970-33-00
- WHO UTN
- U1111-1321-4943
- ClinicalTrials.gov
- NCT04796337
Trial design
CTIS Part I — objectives, methods, condition coding
Main objective
Scope: Pharmacodynamic, Safety, Pharmacokinetic, Efficacy, Therapy
To evaluate the long-term safety and tolerability of sotatercept.
Secondary objectives 1
- To evaluate the long-term efficacy of sotatercept.
Conditions and MedDRA coding
Pulmonary Arterial Hypertension (PAH)
| Version | Level | Code | Term | System organ class |
|---|---|---|---|---|
| 21.1 | PT | 10064911 | Pulmonary arterial hypertension | 100000004855 |
Regulatory references
- Scientific advice from competent authorities
- European Medicines Agency
- Plan to share IPD
- Yes
| EU CT number | Title | Sponsor |
|---|---|---|
| 2023-509138-21-00 | An Open-Label Long-term Follow-up Study to Evaluate the Effects of Sotatercept When Added to Background Pulmonary Arterial Hypertension (PAH) Therapy for the Treatment of PAH | Acceleron Pharma Inc. |
Eligibility criteria
Principal inclusion / exclusion criteria as submitted by sponsor
Inclusion criteria 2
- Has completed the MK-7962-004 study requirements.
- Is willing to adhere to the study visit schedule, and understands and will comply with all protocol requirements.
Exclusion criteria 2
- Is or has an immediate family member who is investigational site or Sponsor staff directly involved with this study.
- Is currently enrolled in another investigational product study other than a sotatercept study.
Endpoints
Primary and secondary outcome measures (English text)
Primary endpoints 8
- Number of Participants Who Experience an Adverse Event (AE)
- Number of Participants Who Discontinue Study Treatment Due to an AE
- Number of Participants With Detectable Anti-drug Antibodies (ADAs)
- Hematology Parameters: Concentration of Red Blood Cell Count, White Blood Cell Count, Platelet Count, Hemoglobin, and Hematocrit
- Chemistry Parameters: Concentration of Blood Urea,Creatinine,Total & Direct Bilirubin,Aspartate Aminotransferase,Alanine Transaminase,Alkaline Phosphatase,Sodium,Potassium,Chloride,Calcium,Phosphorous,Glucose,Magnesium,Carbon Dioxide, & Albumin
- Change From Baseline in Body Weight
- Change From Baseline in Blood Pressure
- Change From Baseline in Electrocardiogram (ECG)
Secondary endpoints 5
- Change From Baseline in 6-Minute Walk Distance (6MWD)
- Change From Baseline in N-Terminal Pro-Hormone B-type Natriuretic Peptide (NT-proBNP) Levels
- Change From Baseline in the Percentage of Participants Who Improve or Show Maintenance in Modified New York Heart Association/World Health Organization Classification of Functional Status (WHO FC)
- Change From Baseline in Pulmonary Vascular Resistance (PVR)
- Change From Baseline in Percentage of Participants Who Maintain or Achieve a Low-Risk Score Using the Simplified French Risk Score Calculator
Investigational products
Investigational medicinal products (IMPs), comparators, placebo, auxiliary
Test 4
SUB189200 · Substance
- Active substance
- Sotatercept
- Pharmaceutical form
- SOLUTION FOR INJECTION
- Route of administration
- SUBCUTANEOUS USE
- Max daily dose
- 0.7 mg/kg milligram(s)/kilogram
- Max total dose
- 37 mg/kg milligram(s)/kilogram
- Max treatment duration
- 36 Month(s)
- Authorisation status
- Authorised
- ATC code
- - — -
- Marketing authorisation
- -
- Paediatric formulation
- No
- Orphan designation
- Yes
- Orphan designation number
- EU/3/20/2369
- Modified vs. Marketing Authorisation
- No
PRD9659365 · Product
- Active substance
- Sotatercept
- Pharmaceutical form
- SOLUTION FOR INJECTION
- Route of administration
- SUBCUTANEOUS USE
- Max daily dose
- 0.7 mg/kg milligram(s)/kilogram
- Max total dose
- 37 mg/kg milligram(s)/kilogram
- Max treatment duration
- 36 Month(s)
- Authorisation status
- Not Authorised
- MA holder
- MERCK & CO. INC.
- Paediatric formulation
- No
- Orphan designation
- Yes
- Orphan designation number
- EU/3/20/2369
PRD9659366 · Product
- Active substance
- Sotatercept
- Pharmaceutical form
- SOLUTION FOR INJECTION
- Route of administration
- SUBCUTANEOUS USE
- Max daily dose
- 0.7 mg/kg milligram(s)/kilogram
- Max total dose
- 37 mg/kg milligram(s)/kilogram
- Max treatment duration
- 36 Month(s)
- Authorisation status
- Not Authorised
- MA holder
- MERCK & CO. INC.
- Paediatric formulation
- No
- Orphan designation
- Yes
- Orphan designation number
- EU/3/20/2369
SUB189200 · Substance
- Active substance
- Sotatercept
- Pharmaceutical form
- SOLUTION FOR INJECTION
- Route of administration
- SUBCUTANEOUS USE
- Max daily dose
- 0.7 mg/kg milligram(s)/kilogram
- Max total dose
- 37 mg/kg milligram(s)/kilogram
- Max treatment duration
- 36 Month(s)
- Authorisation status
- Authorised
- ATC code
- - — -
- Marketing authorisation
- -
- Paediatric formulation
- No
- Orphan designation
- Yes
- Orphan designation number
- EU/3/20/2369
- Modified vs. Marketing Authorisation
- No
Sponsors and contacts
Sponsor organisations, regulatory contacts, third parties
Merck Sharp & Dohme LLC
- Sponsor organisation
- Merck Sharp & Dohme LLC
- Address
- 126 East Lincoln Avenue, P. O. Box 2000 P. O. Box 2000
- City
- Rahway
- Postcode
- 07065-4607
- Country
- United States
Scientific contact point
- Organisation
- Merck Sharp & Dohme LLC
- Contact name
- Howard Julien
Public contact point
- Organisation
- Merck Sharp & Dohme LLC
- Contact name
- Howard Julien
Third parties 6
| Organisation | City, country | Duties |
|---|---|---|
| Parexel International Corp. ORG-100007310
|
Auburndale, United States | Other |
| Pra International ORG-100032850
|
Blue Bell, United States | Other |
| PPD Global Central Labs ORG-100046496
|
Zaventem, Belgium | Laboratory analysis |
| Pra International ORG-100032850
|
Blue Bell, United States | Other |
| Almac Clinical Technologies LLC ORG-100043036
|
Souderton, United States | Interactive response technologies (IRT) |
| QPS LLC ORG-100012847
|
Newark, United States | Laboratory analysis |
Locations
13 EU/EEA countries · 55 investigational sites
By country
| Country | MS status | Planned subjects | Sites |
|---|---|---|---|
| Belgium | Ongoing, recruitment ended | 10 | 2 |
| Croatia | Ongoing, recruitment ended | 1 | 1 |
| Czechia | Ongoing, recruitment ended | 24 | 2 |
| Denmark | Ongoing, recruitment ended | 8 | 2 |
| France | Ongoing, recruiting | 71 | 13 |
| Germany | Ongoing, recruiting | 148 | 11 |
| Greece | Ongoing, recruiting | 12 | 3 |
| Italy | Ongoing, recruitment ended | 18 | 4 |
| Netherlands | Ongoing, recruitment ended | 12 | 3 |
| Poland | Ongoing, recruiting | 27 | 2 |
| Portugal | Ongoing, recruitment ended | 10 | 2 |
| Spain | Ongoing, recruitment ended | 47 | 9 |
| Sweden | Ongoing, recruitment ended | 1 | 1 |
| Rest of world
Israel, Canada, Korea, Republic of, Taiwan, Argentina, United States, Mexico, Serbia, New Zealand, Australia, Colombia, Switzerland, United Kingdom, Brazil
|
— | 418 | — |
Investigational sites
Country notifications
Trial-start, recruitment-start, end and early-termination notifications submitted per Member State
| Country | Trial start | Trial end | Recruitment start | Recruitment end | Early termination |
|---|---|---|---|---|---|
| Belgium | 2026-02-25 | 2026-03-03 | 2026-05-05 | ||
| Croatia | 2026-03-27 | 2026-04-17 | 2026-04-17 | ||
| Czechia | 2026-01-27 | 2026-02-03 | 2026-04-02 | ||
| Denmark | 2025-12-19 | 2026-01-23 | 2026-02-11 | ||
| France | 2026-01-12 | 2026-01-27 | |||
| Germany | 2026-04-09 | 2026-04-15 | |||
| Greece | 2026-03-12 | 2026-03-13 | |||
| Italy | 2026-02-23 | 2026-03-04 | 2026-05-04 | ||
| Netherlands | 2025-12-22 | 2026-02-10 | 2026-03-25 | ||
| Poland | 2026-04-30 | 2026-05-12 | |||
| Portugal | 2026-02-25 | 2026-03-12 | 2026-05-28 | ||
| Spain | 2025-12-19 | 2025-12-29 | 2026-04-16 | ||
| Sweden | 2026-01-14 | 2026-02-03 | 2026-02-03 |
Results and documents
Annex IV summary of results, Annex V layperson summary, and all documents registered in CTIS for this trial
Documents 94 files
Public protocol annexes, IB summaries, regulatory submissions and post-authorisation documents registered in CTIS.
| Type | Title | Version |
|---|---|---|
| Protocol (for publication) | D1_Protocol_2025-521970-33_GRC_EL_IN_for pub | 00R |
| Protocol (for publication) | D1_Protocol_2025-521970-33_IN_for pub | 00R |
| Recruitment arrangements (for publication) | K1_Recruitment Arrangements and IC Procedure_BEL_EN_IN-RFI006_for pub | 20OCT2025 |
| Recruitment arrangements (for publication) | K1_Recruitment Arrangements and IC Procedure_CZE_CS_IN_for pub | 30JUL2025 |
| Recruitment arrangements (for publication) | K1_Recruitment Arrangements and IC Procedure_DEU_EN_IN_for pub | 1.0 |
| Recruitment arrangements (for publication) | K1_Recruitment Arrangements and IC Procedure_DNK_EN_IN-RFI014_for pub | 1.0 |
| Recruitment arrangements (for publication) | K1_Recruitment Arrangements and IC Procedure_ESP_ES_IN-RFI011_for pub | 28OCT2025R |
| Recruitment arrangements (for publication) | K1_Recruitment Arrangements and IC Procedure_FRA_FR_IN_for pub | 04AUG2025 |
| Recruitment arrangements (for publication) | K1_Recruitment Arrangements and IC Procedure_GRC_EN_IN_for pub | 1.0 |
| Recruitment arrangements (for publication) | K1_Recruitment Arrangements and IC Procedure_HRV_EN_IN_for pub | 0.00 |
| Recruitment arrangements (for publication) | K1_Recruitment Arrangements and IC Procedure_ITA_EN_IN_for pub | 21JUL2025 |
| Recruitment arrangements (for publication) | K1_Recruitment Arrangements and IC Procedure_NLD_EN_IN-RFI020_for pub | v3.0 |
| Recruitment arrangements (for publication) | K1_Recruitment Arrangements and IC Procedure_POL_PL_IN_for pub | 1.0 |
| Recruitment arrangements (for publication) | K1_Recruitment Arrangements and IC Procedure_PRT_EN_IN_for pub | 1 |
| Recruitment arrangements (for publication) | K1_Recruitment Arrangements and IC Procedure_SWE_SV_IN_for pub | 1.0 |
| Recruitment arrangements (for publication) | K2_Recruitment Doc Patient Letter_BEL_FR_IN-RFI006_for pub | v00.1 |
| Recruitment arrangements (for publication) | K2_Recruitment Doc Patient Letter_BEL_NL_IN-RFI006_for pub | v00.1 |
| Subject information and informed consent form (for publication) | L1_ICF_FBR consent_CZE_CS_IN-RFI010_for pub | 1 |
| Subject information and informed consent form (for publication) | L1_ICF_FBR consent_DNK_DA_IN-RFI014_for pub | 00 |
| Subject information and informed consent form (for publication) | L1_ICF_FBR consent_GRC_EL_IN_for pub | 00 |
| Subject information and informed consent form (for publication) | L1_ICF_FBR consent_HRV_HR_IN-RFI008_for pub | 0.00 |
| Subject information and informed consent form (for publication) | L1_ICF_FBR consent_POL_PL_IN-RFI022_for pub | 00 |
| Subject information and informed consent form (for publication) | L1_ICF_Genetic consent_PRT_PT_IN_for pub | 00 |
| Subject information and informed consent form (for publication) | L1_ICF_Main adult consent_ESP_ES_IN-RFI011_for pub | 00R |
| Subject information and informed consent form (for publication) | L1_ICF_Main consent_BEL_EN_IN-RFI006_for pub | v0.00R |
| Subject information and informed consent form (for publication) | L1_ICF_Main consent_BEL_FR_IN-RFI006_for pub | v0.00R |
| Subject information and informed consent form (for publication) | L1_ICF_Main consent_BEL_NL_IN-RFI019_for pub | v0.00R |
| Subject information and informed consent form (for publication) | L1_ICF_Main consent_CZE_CS_IN-RFI010_for pub | 1R |
| Subject information and informed consent form (for publication) | L1_ICF_Main consent_DEU_DE_SM06_for pub | 0.0R |
| Subject information and informed consent form (for publication) | L1_ICF_Main consent_DNK_DA_SM02_for pub | 00R |
| Subject information and informed consent form (for publication) | L1_ICF_Main consent_FRA_FR_IN_for pub | 0.00R |
| Subject information and informed consent form (for publication) | L1_ICF_Main consent_GRC_EL_IN_for pub | 00 |
| Subject information and informed consent form (for publication) | L1_ICF_Main consent_HRV_HR_IN-RFI008_for pub | 0.00R |
| Subject information and informed consent form (for publication) | L1_ICF_Main consent_ITA_IT_IN-RFI002_for pub | 00 |
| Subject information and informed consent form (for publication) | L1_ICF_Main consent_NLD_NL_SM13_for pub | v0.00R |
| Subject information and informed consent form (for publication) | L1_ICF_Main consent_POL_PL_IN-RFI013_for pub | 00R |
| Subject information and informed consent form (for publication) | L1_ICF_Main consent_PRT_PT_IN-RFI004_for pub | 00 |
| Subject information and informed consent form (for publication) | L1_ICF_Main consent_SWE_SV_IN-RFI007_for pub | v0.00 |
| Subject information and informed consent form (for publication) | L1_ICF_Main data privacy_ITA_IT_NSM01_for pub | 01 |
| Subject information and informed consent form (for publication) | L1_ICF_Main GDPR_CZE_CS_IN_for pub | Czech v3.0 |
| Subject information and informed consent form (for publication) | L1_ICF_Main survival follow-up_BEL_EN_SM04_for pub | v0.01R |
| Subject information and informed consent form (for publication) | L1_ICF_Main survival follow-up_BEL_FR_SM04_for pub | v0.01R |
| Subject information and informed consent form (for publication) | L1_ICF_Main survival follow-up_BEL_NL_SM04_for pub | v0.01R |
| Subject information and informed consent form (for publication) | L1_ICF_Main survival follow-up_DEU_DE_SM06_for pub | 0.1R |
| Subject information and informed consent form (for publication) | L1_ICF_Main survival follow-up_DNK_DA_IN-RFI014_for pub | 00R |
| Subject information and informed consent form (for publication) | L1_ICF_Main survival follow-up_ESP_ES_IN_for pub | 00 |
| Subject information and informed consent form (for publication) | L1_ICF_Main survival follow-up_FRA_FR_IN_for pub | 0.00R |
| Subject information and informed consent form (for publication) | L1_ICF_Main survival follow-up_GRC_EL_SM07_for pub | 01 |
| Subject information and informed consent form (for publication) | L1_ICF_Main survival follow-up_HRV_HR_IN-RFI008_for pub | 0.00 |
| Subject information and informed consent form (for publication) | L1_ICF_Main survival follow-up_ITA_IT_SM08_for pub | 01 |
| Subject information and informed consent form (for publication) | L1_ICF_Main survival follow-up_NLD_NL_IN-RFI020_for pub | v0.00R |
| Subject information and informed consent form (for publication) | L1_ICF_Main survival follow-up_POL_PL_SM10_for pub | 01R |
| Subject information and informed consent form (for publication) | L1_ICF_Main survival follow-up_PRT_PT_SM11_for pub | 01 |
| Subject information and informed consent form (for publication) | L1_ICF_Main survival follow-up_SWE_SV_IN-RFI007_for pub | v0.00 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_additional treatment_DEU_DE_SM06_for pub | 0.0 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_DILI sample_ITA_IT_NSM01_for pub | 01 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_Greenphire adults_CZE_CS_IN_for pub | Czech v1 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_Greenphire adults_DEU_DE_IN_for pub | 0.0 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_Greenphire adults_GRC_EL_IN_for pub | 0.1 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_Greenphire adults_POL_PL_SM10_for pub | 01 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_Greenphire adults_PRT_PT_IN_for pub | 01 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_Greenphire adults_SWE_SV_IN-RFI007_for pub | v0.01 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_Home healthcare_FRA_FR_SM03_for pub | v0.00 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_infant follow-up_POL_PL_IN_for pub | 00 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_pregnancy follow-up_ESP_ES_IN_for pub | 00 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_pregnancy follow-up_HRV_HR_IN_for pub | 0.00 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_pregnancy follow-up_POL_PL_IN_for pub | 00 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_pregnancy follow-up_PRT_PT_IN_for pub | 00 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_pregnant partner assent_HRV_HR_IN_for pub | 0.00 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_pregnant partner parent_HRV_HR_IN-RFI008_for pub | 0.00 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_pregnant partner_BEL_EN_IN-RFI006_for pub | v0.00R |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_pregnant partner_BEL_FR_IN-RFI006_for pub | v0.00R |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_pregnant partner_BEL_NL_IN-RFI006_for pub | v0.00R |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_pregnant partner_ESP_ES_IN_for pub | 00R |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_pregnant partner_HRV_HR_IN_for pub | 0.00 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_right not to know_DNK_DA_IN-RFI014_for pub | 00 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_survival follow-up_CZE_CS_IN-RFI010_for pub | 1 |
| Subject information and informed consent form (for publication) | L1_ICF_Optional_withdrawal_PRT_PT_IN_for pub | 00 |
| Synopsis of the protocol (for publication) | D1_PPLS_2025-521970-33_BEL_DE_IN_for pub | 1.0 |
| Synopsis of the protocol (for publication) | D1_PPLS_2025-521970-33_BEL_FR_IN_for pub | 1.0 |
| Synopsis of the protocol (for publication) | D1_PPLS_2025-521970-33_BEL_NL_IN_for pub | 1.0 |
| Synopsis of the protocol (for publication) | D1_PPLS_2025-521970-33_CZE_CS_IN_for pub | 1.0 |
| Synopsis of the protocol (for publication) | D1_PPLS_2025-521970-33_DEU_DE_IN_for pub | 1.0 |
| Synopsis of the protocol (for publication) | D1_PPLS_2025-521970-33_ESP_ES_IN_for pub | 1.0 |
| Synopsis of the protocol (for publication) | D1_PPLS_2025-521970-33_FRA_FR_IN_for pub | 1.0 |
| Synopsis of the protocol (for publication) | D1_PPLS_2025-521970-33_GRC_EL_IN_for pub | 1.0 |
| Synopsis of the protocol (for publication) | D1_PPLS_2025-521970-33_HRV_HR_IN_for pub | 1.0 |
| Synopsis of the protocol (for publication) | D1_PPLS_2025-521970-33_IN_for pub | 1.0 |
| Synopsis of the protocol (for publication) | D1_PPLS_2025-521970-33_ITA_IT_IN_for pub | 1.0 |
| Synopsis of the protocol (for publication) | D1_PPLS_2025-521970-33_NLD_NL_IN_for pub | 1.0 |
| Synopsis of the protocol (for publication) | D1_PPLS_2025-521970-33_POL_PL_IN_for pub | 1.0 |
| Synopsis of the protocol (for publication) | D1_PPLS_2025-521970-33_PRT_PT_IN_for pub | 1 |
| Synopsis of the protocol (for publication) | D1_PPLS_2025-521970-33_SWE_SV_IN_for pub | 1.0 |
| Synopsis of the protocol (for publication) | D1_Protocol Scientific Synopsis_2025-521970-33_CZE_CS_IN_for pub | 1.0 |
Application history
12 submissions — initial application plus substantial / non-substantial modifications
| # | Type | Code | Submitted | Reference MS | Conclusion | Decision date |
|---|---|---|---|---|---|---|
| 1 | INITIAL | IN | 2025-08-11 | Denmark | Acceptable 2025-12-01
|
2025-12-01 |
| 2 | NON SUBSTANTIAL MODIFICATION | NSM-1 | 2026-01-09 | Acceptable 2025-12-01
|
2026-01-09 | |
| 3 | SUBSTANTIAL MODIFICATION | SM-1 | 2026-01-22 | Acceptable | 2026-03-02 | |
| 4 | SUBSTANTIAL MODIFICATION | SM-2 | 2026-02-02 | Denmark | Acceptable | 2026-02-25 |
| 5 | SUBSTANTIAL MODIFICATION | SM-3 | 2026-02-20 | Acceptable | 2026-03-16 | |
| 6 | SUBSTANTIAL MODIFICATION | SM-4 | 2026-03-24 | Acceptable | 2026-04-09 | |
| 7 | SUBSTANTIAL MODIFICATION | SM-6 | 2026-03-24 | Acceptable | 2026-04-29 | |
| 8 | SUBSTANTIAL MODIFICATION | SM-7 | 2026-03-25 | Acceptable | 2026-05-04 | |
| 9 | SUBSTANTIAL MODIFICATION | SM-10 | 2026-03-25 | Acceptable | 2026-05-06 | |
| 10 | SUBSTANTIAL MODIFICATION | SM-11 | 2026-03-25 | Acceptable | 2026-04-23 | |
| 11 | SUBSTANTIAL MODIFICATION | SM-8 | 2026-03-26 | Acceptable | 2026-04-29 | |
| 12 | SUBSTANTIAL MODIFICATION | SM-13 | 2026-03-26 | Acceptable | 2026-04-08 |