AzTrials
AzTrials

Thrombocythemia, EssentialPhase 3NCT06351631

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

A Phase 3 study testing Bomedemstat in people with Thrombocythemia, Essential and Primary Myelofibrosis, run by Merck Sharp & Dohme LLC at 21 sites in 6 countries.

Recruiting

Looking for participants now. Contact the study team or a site below to ask about taking part.

Sites and contacts
Official record
Search all trials

Trial summary

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… Read more about this study

Who is it for?
Ages 18 years and older
What is being tested?
Bomedemstat
Type of treatment
Pill or oral medicine
Could I receive a placebo?
No, everyone receives an active treatment
How many people
400 participants
Where
21 sitesin 6 countries
Study dates
23 May 2024to 4 Dec 2034
Phase
Phase 3
Are there results?
Not yet: the study is under way

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 years and older
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • 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

Who cannot join

  • 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

Trial locations and contacts

21 sites in 6 countries. Contact the study team or a site near you to ask about taking part.

Toll Free Number contact

1-888-577-8839

Trialsites@msd.com

21 sites in 6 countries

Australia6 sites, 6 recruiting

  • Royal Adelaide Hospital-Haematology Clinical Trials Unit ( Site 1000)

    Adelaide, South Australia, 5000

    Study Coordinator, +61870740000

    Recruiting

  • Sunshine Coast Hematology and Oncology Clinic ( Site 1006)

    Buderim, Queensland, 4556

    Study Coordinator, +61754790000

    Recruiting

  • Royal Prince Alfred Hospital ( Site 1003)

    Camperdown, New South Wales, 2050

    Study Coordinator, +61295155720

    Recruiting

  • Monash Health ( Site 1004)

    Clayton, Victoria, 3168

    Study Coordinator, +61395956111

    Recruiting

  • Gold Coast University Hospital-Cancer and Blood Disorders Clinical Trial Team ( Site 1002)

    Southport, Queensland, 4215

    Study Coordinator, +61756872712

    Recruiting

  • Royal North Shore Hospital ( Site 1001)

    St Leonards, New South Wales, 2065

    Study Coordinator, +61299264383

    Recruiting

Other trials in Australia

United States4 sites, 4 recruiting

  • University of Michigan ( Site 6000)

    Ann Arbor, Michigan, 48109

    Study Coordinator, 734-763-4695

    Recruiting

  • The James Cancer Hospital and Solove Research Institute at The Ohio State University Comprehensive C ( Site 6007)

    Columbus, Ohio, 43210

    Study Coordinator, 888-577-8839

    Recruiting

  • DUHS Duke Blood Cancer Center ( Site 6005)

    Durham, North Carolina, 27705

    Study Coordinator, 919-668-1608

    Recruiting

  • UPMC Hillman Cancer Center ( Site 6004)

    Pittsburgh, Pennsylvania, 15232

    Study Coordinator, 412-864-6627

    Recruiting

Other trials in United States

Italy4 sites, 4 recruiting

  • Azienda Ospedaliero-Universitaria SS. Antonio e Biagio e Cesare Arrigo ( Site 2703)

    Alessandria, 15121

    Study Coordinator, +39 0131 206440

    Recruiting

  • IRCCS Azienda Ospedaliero-Universitaria di Bologna, Policlinico di Sant'Orsola ( Site 2702)

    Bologna, 40138

    Study Coordinator, +390512143044

    Recruiting

  • Azienda Ospedaliera Universitaria Careggi ( Site 2700)

    Florence, Tuscany, 50134

    Study Coordinator, +39 0131 206440

    Recruiting

  • Ospedale di Circolo e Fondazione Macchi Varese ( Site 2701)

    Varese, 21100

    Study Coordinator, +390332393906

    Recruiting

Other trials in Italy

United Kingdom4 sites, 4 recruiting

  • Boston Pilgrim Hospital ( Site 3403)

    Boston, Lincolnshire, PE21 9QS

    Study Coordinator, 01205 446311

    Recruiting

  • Imperial College Healthcare NHS Trust - Hammersmith Hospital ( Site 3402)

    London, Hammersmith and Fulham, W12 0HS

    Study Coordinator, +442083834340

    Recruiting

  • University College London Hospital ( Site 3400)

    London, London, City of, NW1 2PG

    Study Coordinator, +442034472528

    Recruiting

  • Guy's & St Thomas' NHS Foundation Trust ( Site 3401)

    London, London, City of, SE1 9RT

    Study Coordinator, +442071884259

    Recruiting

Other trials in United Kingdom

New Zealand2 sites

  • North Shore Hospital-Department of Haematology ( Site 1401)

    Auckland, 0622

    Active, not recruiting

  • Aotearoa Clinical Trials ( Site 1400)

    Auckland, 2025

    Active, not recruiting

Other trials in New Zealand

Hong Kong1 site

  • Queen Mary Hospital ( Site 1601)

    Hksar

    Active, not recruiting

Other trials in Hong Kong

About this study

Official title: 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.

Being tested
Bomedemstat
Medical subject headings
Thrombocythemia, Essential, Primary Myelofibrosis, Polycythemia Vera

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • BomedemstatDrug

    Also called MK-3543, IMG-7289

    10, 15, 20, and 50 mg oral capsules

Study groups in NCT06351631
Study groupRoleWhat they receive
BomedemstatExperimentalParticipants 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.
Receives: Drug: Bomedemstat

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Percentage of participants with one or more adverse events (AEs)

    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.

    Measured: Up to ~10 years

  2. Percentage of participants who discontinued study treatment due to an AE

    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.

    Measured: Up to ~10 years

Secondary outcomes (6)

  1. For participants with ET or PV: Duration of clinicohematologic response

    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.

    Measured: Up to ~10 years

  2. For participants with ET or PV: Duration of hematologic remission

    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.

    Measured: Up to ~10 years

  3. For participants with ET or PV: Percentage of participants with transformation to MF or MDS/AML

    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.

    Measured: Up to ~10 years

  4. For participants with MF: Percentage of participants with worsening of splenomegaly or transformation to MDS/AML

    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.

    Measured: Up to ~10 years

  5. For participants with MF, ET, or PV: Percentage of participants with thrombotic events

    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.

    Measured: Up to ~10 years

  6. For participants with MF, ET, or PV: Percentage of participants with major hemorrhagic events

    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.

    Measured: Up to ~10 years

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted8 Apr 2024
  2. Study start23 May 2024
  3. Primary completion4 Dec 2034 (estimated)
  4. Study completion4 Dec 2034 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase 3
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrolment
400 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT06351631
Sponsor's protocol ID
3543-017
Other IDs
2023-506996-89-00, U1111-1294-8621, MK-3543-017, 2023
Status last verified
Apr 2026
First submitted
2 Apr 2024
Last updated
2 Apr 2026
Results posted
No
Data monitoring committee
No
FDA-regulated drug
Yes
FDA-regulated device
No
Individual data sharing
Yes: https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf

Questions about this trial

What is this clinical trial studying?

A Phase 3 study testing Bomedemstat in people with Thrombocythemia, Essential and Primary Myelofibrosis, run by Merck Sharp & Dohme LLC at 21 sites in 6 countries.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 5 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: looking for participants now, as of the sponsor's last update on 2 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 21 sites in Australia, United States, Italy, United Kingdom, New Zealand and 1 more country. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

Contact Toll Free Number (1-888-577-8839, Trialsites@msd.com), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Percentage of participants with one or more adverse events (AEs) (time frame: Up to ~10 years). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT06351631.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 2 Apr 2026.

AzTrials uses cookies for analytics and advertising. You can accept or reject them; the site works either way. Privacy Policy.

Free account

Log in to keep searching

You’ve used your 3 free searches. AzTrials is free: log in or create a free account to keep searching clinical trials and save the ones you want to follow.

Create a free accountLog in