A Study to Evaluate Safety and Efficacy of Bomedemstat (MK-3543-017)

April 1, 2026 updated by: Merck Sharp & Dohme LLC

A Multicenter, Open-Label, Extension Study Evaluating the Safety and Efficacy of Bomedemstat for the Treatment of Participants Enrolled in a Prior Bomedemstat Clinical Study

The primary purpose of the study is to transition participants into an extension study to collect long-term safety and efficacy data. The study will include participants who are safely tolerating bomedemstat, receiving clinical benefit from its use in estimation of the investigator, and have shown the following criteria:

  • Participants from the IMG-7289-202/MK-3543-005 (NCT05223920) study must have received at least 6 months of treatment with bomedemstat;
  • Essential thrombocythemia (ET) and polycythemia vera (PV) participants from studies other than IMG-7289-202/MK-3543-005 must have achieved confirmed hematologic remission.

No hypothesis testing will be conducted in this study.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

400

Phase

  • Phase 3

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • Australia
    • New South Wales
      • Camperdown, New South Wales, Australia, 2050
        • Recruiting
        • Royal Prince Alfred Hospital ( Site 1003)
        • Contact:
          • Study Coordinator
          • Phone Number: +61295155720
      • St Leonards, New South Wales, Australia, 2065
        • Recruiting
        • Royal North Shore Hospital ( Site 1001)
        • Contact:
          • Study Coordinator
          • Phone Number: +61299264383
    • Queensland
      • Buderim, Queensland, Australia, 4556
        • Recruiting
        • Sunshine Coast Hematology and Oncology Clinic ( Site 1006)
        • Contact:
          • Study Coordinator
          • Phone Number: +61754790000
      • Southport, Queensland, Australia, 4215
        • Recruiting
        • Gold Coast University Hospital-Cancer and Blood Disorders Clinical Trial Team ( Site 1002)
        • Contact:
          • Study Coordinator
          • Phone Number: +61756872712
    • South Australia
      • Adelaide, South Australia, Australia, 5000
        • Recruiting
        • Royal Adelaide Hospital-Haematology Clinical Trials Unit ( Site 1000)
        • Contact:
          • Study Coordinator
          • Phone Number: +61870740000
    • Victoria
      • Clayton, Victoria, Australia, 3168
        • Recruiting
        • Monash Health ( Site 1004)
        • Contact:
          • Study Coordinator
          • Phone Number: +61395956111
  • Hong Kong
      • Hksar, Hong Kong
        • Active, not recruiting
        • Queen Mary Hospital ( Site 1601)
  • Italy
      • Alessandria, Italy, 15121
        • Recruiting
        • Azienda Ospedaliero-Universitaria SS. Antonio e Biagio e Cesare Arrigo ( Site 2703)
        • Contact:
          • Study Coordinator
          • Phone Number: +39 0131 206440
      • Bologna, Italy, 40138
        • Recruiting
        • IRCCS Azienda Ospedaliero-Universitaria di Bologna, Policlinico di Sant'Orsola ( Site 2702)
        • Contact:
          • Study Coordinator
          • Phone Number: +390512143044
      • Varese, Italy, 21100
        • Recruiting
        • Ospedale di Circolo e Fondazione Macchi Varese ( Site 2701)
        • Contact:
          • Study Coordinator
          • Phone Number: +390332393906
    • Tuscany
      • Florence, Tuscany, Italy, 50134
        • Recruiting
        • Azienda Ospedaliera Universitaria Careggi ( Site 2700)
        • Contact:
          • Study Coordinator
          • Phone Number: +39 0131 206440
  • New Zealand
      • Auckland, New Zealand, 0622
        • Active, not recruiting
        • North Shore Hospital-Department of Haematology ( Site 1401)
      • Auckland, New Zealand, 2025
        • Active, not recruiting
        • Aotearoa Clinical Trials ( Site 1400)
  • United Kingdom
    • Hammersmith and Fulham
      • London, Hammersmith and Fulham, United Kingdom, W12 0HS
        • Recruiting
        • Imperial College Healthcare NHS Trust - Hammersmith Hospital ( Site 3402)
        • Contact:
          • Study Coordinator
          • Phone Number: +442083834340
    • Lincolnshire
      • Boston, Lincolnshire, United Kingdom, PE21 9QS
        • Recruiting
        • Boston Pilgrim Hospital ( Site 3403)
        • Contact:
          • Study Coordinator
          • Phone Number: 01205 446311
    • London, City of
      • London, London, City of, United Kingdom, NW1 2PG
        • Recruiting
        • University College London Hospital ( Site 3400)
        • Contact:
          • Study Coordinator
          • Phone Number: +442034472528
      • London, London, City of, United Kingdom, SE1 9RT
        • Recruiting
        • Guy's & St Thomas' NHS Foundation Trust ( Site 3401)
        • Contact:
          • Study Coordinator
          • Phone Number: +442071884259
  • United States
    • Michigan
      • Ann Arbor, Michigan, United States, 48109
        • Recruiting
        • University of Michigan ( Site 6000)
        • Contact:
          • Study Coordinator
          • Phone Number: 734-763-4695
    • North Carolina
      • Durham, North Carolina, United States, 27705
        • Recruiting
        • DUHS Duke Blood Cancer Center ( Site 6005)
        • Contact:
          • Study Coordinator
          • Phone Number: 919-668-1608
    • Ohio
      • Columbus, Ohio, United States, 43210
        • Recruiting
        • The James Cancer Hospital and Solove Research Institute at The Ohio State University Comprehensive C ( Site 6007)
        • Contact:
          • Study Coordinator
          • Phone Number: 888-577-8839
    • Pennsylvania
      • Pittsburgh, Pennsylvania, United States, 15232
        • Recruiting
        • UPMC Hillman Cancer Center ( Site 6004)
        • Contact:
          • Study Coordinator
          • Phone Number: 412-864-6627

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Is from a bomedemstat study sponsored by Imago BioSciences, Inc. (a subsidiary of Merck & Co., Inc.) or MSD, and established by the Sponsor as MK-3543-017 ready
  • Has received at least 6 months of treatment with bomedemstat in the IMG-7289-202/MK-3543-005 study, while safely tolerating bomedemstat, and receiving clinical benefit from its use in the estimation of the investigator
  • ET and PV participants from established feeder studies other than IMG-7289- 202/MK-3543-005 must have achieved confirmed hematologic remission, must be safely tolerating bomedemstat, and must be receiving clinical benefit from its use in the estimation of the investigator
  • Is not currently on a dose hold
  • Participant must be able to swallow oral medication and follow instructions for at-home dosing of bomedemstat

Exclusion Criteria:

  • Has received prohibited concomitant medications
  • Ongoing or planned participation in another investigational study
  • Has noncompliance in prior bomedemstat study receiving <90% of assigned doses excluding suspensions or holds as assigned by the investigator

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

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

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Bomedemstat
Participants will receive oral capsules of bomedemstat once daily for up to 10 years, with the starting dose as the same dose that the participant was on at the time of transition from the feeder study.
Drug: Bomedemstat
10, 15, 20, and 50 mg oral capsules
Other Names:
  • IMG-7289
  • MK-3543

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Percentage of participants with one or more adverse events (AEs)
Time Frame: Up to ~10 years
An AE is any undesirable physical, psychological or behavioral effect experienced by a patient during participation in an investigational study, in conjunction with the use of the drug or biologic, whether or not product-related. This includes any untoward signs or symptoms experienced by the patient from the time of first dose with bomedemstat under this protocol until completion of the study. The percentage of participants with AEs will be presented.
Up to ~10 years
Percentage of participants who discontinued study treatment due to an AE
Time Frame: Up to ~10 years
An AE is any undesirable physical, psychological or behavioral effect experienced by a patient during participation in an investigational study, in conjunction with the use of the drug or biologic, whether or not product-related. This includes any untoward signs or symptoms experienced by the patient from the time of first dose with bomedemstat under this protocol until completion of the study. The percentage of participants who discontinued study treatment due to an AE will be presented.
Up to ~10 years

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
For participants with ET or PV: Duration of clinicohematologic response
Time Frame: Up to ~10 years
For participants who showed durable clinicohematologic response (DCHR) in their feeder studies, duration of clinicohematologic response is defined as the time from the first documented evidence of confirmed reduction of platelet and white blood cell (WBC) count until confirmed increase of platelet and WBC counts to above acceptable threshold, thrombotic or major hemorrhagic events or disease progression to myelofibrosis (MF), myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML). The duration of clinicohematologic response will be reported.
Up to ~10 years
For participants with ET or PV: Duration of hematologic remission
Time Frame: Up to ~10 years
For participants who showed confirmed hematologic remission in their feeder studies, duration of hematologic remission is defined as the time from the first documented evidence of confirmed reduction of platelet and WBC count until confirmed increase of platelet and WBC counts to above acceptable threshold. The duration of hematologic remission will be reported.
Up to ~10 years
For participants with ET or PV: Percentage of participants with transformation to MF or MDS/AML
Time Frame: Up to ~10 years
Disease Progression is defined as the transformation to post-ET myelofibrosis (ET participants only), post-PV myelofibrosis (PV participants only), spleen volume increase ≥25% (MF participants only), myelodysplastic syndrome, or acute myeloid leukemia as assessed by the investigator. The percentage of participants with transformation to MF or MDS/AML will be reported.
Up to ~10 years
For participants with MF: Percentage of participants with worsening of splenomegaly or transformation to MDS/AML
Time Frame: Up to ~10 years
Spleen volume will be assessed by magnetic resonance imaging (MRI) (or computed tomography [CT] where applicable) at pre-specified timepoints. The percentage of participants with worsening of splenomegaly or transformation to MDS/AML will be reported.
Up to ~10 years
For participants with MF, ET, or PV: Percentage of participants with thrombotic events
Time Frame: Up to ~10 years
Thrombotic events are defined as: new or recurrent acute myocardial infarction; unstable angina; stroke; transient ischemic attack (TIA); deep venous thrombosis (DVT); pulmonary embolism (PE); thrombotic digital ischemia; other thrombotic events such as peripheral limb ischemia or Budd-Chiari syndrome that are assessed to be due to underlying PV; other vascular occlusive events such as symptoms of cardiac, abdominal or peripheral limb ischemia supported by objective evidence of vessel disease and/or ischemia. The percentage of participants with thrombotic events will be presented.
Up to ~10 years
For participants with MF, ET, or PV: Percentage of participants with major hemorrhagic events
Time Frame: Up to ~10 years
Hemorrhagic events are defined as: Major Bleeding (MB) Events such as fatal bleeding, and/or symptomatic bleeding in a critical area or organ such as intracranial, intraspinal, intraocular, retroperitoneal, intra-articular or pericardial, or intramuscular with compartment syndrome, and/or bleeding causing a fall in hemoglobin level of 2 g/dL or more, or leading to transfusion of 2 or more units of whole blood or red cells; Clinically Relevant Non-Major Bleeding (CRNMB) Events Leading to hospitalization or increased level of care or clinically important, prompting a face-to-face medical evaluation. The percentage of participants with major hemorrhagic events will be presented.
Up to ~10 years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Merck Sharp & Dohme LLC

Investigators

  • Study Director: Medical Director, Merck Sharp and Dohme LLC

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

May 23, 2024

Primary Completion (Estimated)

December 4, 2034

Study Completion (Estimated)

December 4, 2034

Study Registration Dates

First Submitted

April 2, 2024

First Submitted That Met QC Criteria

April 2, 2024

First Posted (Actual)

April 8, 2024

Study Record Updates

Last Update Posted (Actual)

April 2, 2026

Last Update Submitted That Met QC Criteria

April 1, 2026

Last Verified

April 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 3543-017
  • U1111-1294-8621 (Registry Identifier: UTN)
  • MK-3543-017 (Other Identifier: MSD)
  • 2023-506996-89-00 (Registry Identifier: EU CT)

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

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Primary Myelofibrosis

Clinical Trials on Bomedemstat

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Ghana

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe