Polycythemia VeraPhase 2/3NCT07722611
A Clinical Trial of Bomedemstat in Participants With Polycythemia Vera (MK-3543-025).
A Phase 2/3 study testing Bomedemstat, Ruxolitinib and Ropeginterferon alfa-2b in people with Polycythemia Vera, run by Merck Sharp & Dohme LLC at 5 sites in 3 countries.
Trial summary
Researchers are looking for new ways to treat polycythemia vera (PV). People with PV may receive treatment to lower the number of red blood cells in the blood, but the usual treatments may not work for everyone. Researchers want to learn if a trial medicine called bomedemstat, also called MK-3543, can treat PV. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Polycythemia Vera
- What is being tested?
- Bomedemstat, Ruxolitinib and Ropeginterferon alfa-2b
- Type of treatment
- Pill or oral medicine, Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 380 participants
- Where
- 5 sitesin 3 countries
- Study dates
- 29 Oct 2026to 30 Nov 2032
- Phase
- Phase 2/3
- 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
- The main inclusion criteria include but are not limited to the following:
- Has confirmed local diagnosis of polycythemia vera (PV) per World Health Organization (WHO) diagnostic criteria for PV
- Must have discontinued prior cytoreductive therapy for condition under study for protocol specified duration
- Has failed at least one prior line of cytoreductive therapy to lower hematocrit
- Has a history of inadequate response, resistance to, or intolerant to hydroxyurea (HU) per protocol specified criteria
- Has no evidence of splenomegaly and no symptoms attributable to splenomegaly, including early satiety, left upper quadrant discomfort, or splenic pain
Show all 11Show fewer
- Has locally assessed bone marrow (BM) fibrosis score of Grade 0 or Grade 1 as per modified version of the European Consensus Criteria for Grading Myelofibrosis
- Human Immunodeficiency Virus (HIV)-infected participants have well controlled HIV on antiretroviral therapy (ART)
- Participants who are Hepatitis B surface antigen (HBsAg) positive are eligible if they have received Hepatitis B Virus (HBV) antiviral therapy for at least 4 weeks and have undetectable HBV viral load
- Participants with history of Hepatitis C Virus (HCV) infection are eligible if HCV viral load is undetectable
- Participants must be able to swallow oral medication and follow instructions for at home dosing of bomedemstat
Who cannot join
- The main exclusion criteria include but are not limited to the following:
- Has history of any illness/impairment of gastrointestinal (GI) function that might interfere with drug absorption
- Has evidence at the time of screening of increased risk of bleeding
- Has history of malignancy, unless potentially curative treatment has been completed with no evidence of malignancy for 2 years
- HIV-infected participants with a history of Kaposi's sarcoma and/or Multicentric Castleman's Disease
- Is currently receiving anticancer therapy
- Has an active infection requiring systemic therapy
- Has had major surgical procedure ≤4 weeks before first dose of study intervention or has not recovered from side effects of major surgical procedure
Trial locations and contacts
5 sites in 3 countries. Contact the study team or a site near you to ask about taking part.
5 sites in 3 countries
United States3 sites, 3 recruiting
- Recruiting
University of Virginia ( Site 5031)
Charlottesville, Virginia, 22908
Study Coordinator, 434-924-9333
- Recruiting
Oncology Associates of Oregon, P.C.(Willamette Valley Cancer Institute) (WVCI) ( Site 8004)
Eugene, Oregon, 97401
Study Coordinator, 541-683-5001
- Recruiting
Medical Oncology Hematology Consultants (MOHC) ( Site 8002)
Newark, Delaware, 19713
Study Coordinator, 302-366-1200
Canada1 site, 1 recruiting
- Recruiting
Princess Margaret Cancer Centre ( Site 4002)
Toronto, Ontario, M5G 2M9
Study Coordinator, 416-946-4501
Israel1 site, 1 recruiting
- Recruiting
Hadassah Medical Center ( Site 2604)
Jerusalem, 9112001
Study Coordinator, +972539101736
About this study
Official title: A Phase 2/3, Randomized, Open-label, Active-comparator-controlled, Parallel-group, Multicenter Study to Evaluate the Safety and Efficacy of Bomedemstat (MK-3543) Versus Best Available Therapy in Participants With Polycythemia Vera Who Have an Inadequate Response to or Are Intolerant to Hydroxyurea
Researchers are looking for new ways to treat polycythemia vera (PV). People with PV may receive treatment to lower the number of red blood cells in the blood, but the usual treatments may not work for everyone. Researchers want to learn if a trial medicine called bomedemstat, also called MK-3543, can treat PV. In this study, researchers will compare bomedemstat to 2 usual treatments for PV.
The goal of this study is to learn if more participants who take bomedemstat reach healthy blood cell counts and avoid major health problems from PV, compared to those who receive a usual treatment.
- Conditions
- Polycythemia Vera
- Being tested
- Bomedemstat, Ruxolitinib, Ropeginterferon alfa-2b
- Medical subject headings
- 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, Bomedemstat tosylate
Oral Capsule
RuxolitinibDrug
Oral Tablet
Ropeginterferon alfa-2bDrug
Subcutaneous Solution
| Study group | Role | What they receive |
|---|---|---|
| Bomedemstat | Experimental | Participants will receive bomedemstat daily for up to approximately 52 weeks. Per protocol, dosage may be adjusted within specified time parameters for each participant to achieve and maintain protocol-specified platelet and hematocrit target ranges. Eligible participants who do not discontinue study treatment at Week 52, may continue to receive study treatment. Receives: Drug: Bomedemstat |
| Best Available Therapy (BAT) | Active comparator | Participants will receive either ropeinterferon alfa-2b or ruxolitinib as determined by investigator. All participants will be treated per respective approved product labels for up to approximately 52 weeks. Receives: Drug: Ruxolitinib; Drug: Ropeginterferon alfa-2b |
What is being measured
The primary outcome is the main question the study is designed to answer.
Clinicohematologic Response (CHR) Rate
CHR Rate is defined as all of the following: (i) a confirmed hematologic remission sustained for at least 12 consecutive weeks by Week 40 through Week 52, (ii) and absence of any of the following as assessed by the adjudication committee Week 52: thrombotic event; major hemorrhagic events; disease progression to myelofibrosis (MF) or myelodysplastic syndrome (MDS)/acute myeloid leukemia (AML). CHR will begin on the date of the first confirmed assessment achieving CHR criteria and will end on the earliest date of the following: 1) day of the first confirmed assessment not achieving CHR criteria, 2) date of first major hemorrhagic event or thrombotic event as assessed by the adjudication committee, or 3) disease progression as assessed by the adjudication committee. The CHR rate will be presented.
Measured: Up to approximately Week 52
Secondary outcomes (12)
Clinicohematologic Response Sustained for a 24-Week Time Period (CHR24)
CHR24 is defined as all of the following: (i) a confirmed hematologic remission sustained for at least 24 consecutive weeks by Week 52, (ii) and absence of any of the following as assessed by the adjudication committee Week 52: thrombotic event; major hemorrhagic events; disease progression to MF or MDS/AML. CHR24 will begin on the date of the first confirmed assessment achieving CHR24 criteria and will end on the earliest date of the following: 1) day of the first confirmed assessment not achieving CHR24 criteria, 2) date of first major hemorrhagic event or thrombotic event as assessed by the adjudication committee, or 3) disease progression as assessed by the adjudication committee. The CHR24 will be presented.
Measured: Up to approximately Week 52
Number of Participants Who Experience an Adverse Event (AE)
An AE is any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. The number of participants who experience AE will be reported.
Measured: Up to approximately Week 52
Number of Participants Who Discontinue Study Treatment Due to an AE
An AE is any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. The number of participants who discontinue study treatment due to an AE will be reported.
Measured: Up to approximately Week 52
Duration of Clinicohematologic Response Sustained for a 24-Week Time Period (DOCHR24)
For participants who show CHR24, DOCHR24 is defined as the time from the first confirmed hematologic remission to first documented evidence of: 1) confirmed platelet increase, confirmed WBC increase, or a required phlebotomy (defined as a confirmed HCT reduction) after latest confirmed hematologic remission date, 2) thrombotic event as assessed by the adjudication committee, 3) major hemorrhagic event as assessed by the adjudication committee, or 4) disease progression to MF or MDS/AML as assessed by the adjudication committee.
Measured: Up to approximately Week 52
Duration of Clinicohematologic Response (DOCHR)
For participants who show CHR, DOCHR is defined as the time from the first confirmed hematologic remission to first documented evidence of: 1) confirmed platelet increase, confirmed WBC increase, or a required phlebotomy (defined as a confirmed HCT reduction) after latest confirmed hematologic remission date, 2) thrombotic event as assessed by the adjudication committee, 3) major hemorrhagic event as assessed by the adjudication committee, or 4) disease progression to MF or MDS/AML as assessed by the adjudication committee.
Measured: Up to approximately Week 52
Duration of Hematologic Remission (DOHR)
For participants who show confirmed hematologic remission, DOHR is defined as the time from the first hematologic remission until loss of hematologic remission.
Measured: Up to approximately Week 52
Number of Participants Who Experience Phlebotomies
Per protocol, a required phlebotomy is defined as confirmed hematocrit (HCT) ≥45% with a ≥3% increase from baseline HCT or confirmed HCT ≥48%. The number of participants who experienced phlebotomies will be presented.
Measured: Up to approximately Week 52
Disease Progression Rate
Disease progression is defined as the transformation to post polycythemia vera myelofibrosis, myelodysplastic syndrome, or acute myeloid leukemia as assessed by the adjudication committee. The disease progression rate will be presented.
Measured: Up to approximately Week 52
Number of Participants Who Experience 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 assessed to be due to underlying polycythemia vera (PV), and 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 number of participants who experience thrombotic events will be presented.
Measured: Up to approximately Week 52
Number of Participants Who Experience Major Hemorrhagic Events
Major hemorrhagic events include but are not limited to fatal bleeding, symptomatic bleeding in a critical area or organ (including intracranial, intraspinal, intraocular, retroperitoneal, intra-articular, pericardial, or intramuscular with compartment syndrome), or bleeding causing a decrease in hemoglobin of 2 g/dL or more or leading to transfusion of 2 or more units of whole blood or red cells, and clinically relevant non-major bleeding events leading to hospitalization or increased level of care or clinically important bleeding prompting a face-to-face medical evaluation.
Measured: Up to approximately Week 52
Change From Baseline in Myelofibrosis Symptom Assessment Form version 4.0 (MFSAF v4) Total Symptom Score
The MFSAF v4.0 is a 7-item participant-reported symptom assessment that asks respondents to report symptom severity at its worst for each of the 7 items on a 0 (Absent) to 10 (Worst Imaginable) numeric rating scale. The MFSAF v4.0 7-day recall format is used. Individual symptoms are assessed on an 11-point numeric rating scale with a total symptom score range of 0 (absent) to 70 (worst imaginable). The change from baseline in MFSAF total score for all symptoms will be presented
Measured: Up to approximately Week 52
Change From Baseline in Patient-Reported Outcomes Measurement Information System (PROMIS) Fatigue Short Form (SF) 7a Total Fatigue Score
The PROMIS Fatigue SF is a 7-item participant-reported assessment that measures both the experience of fatigue and the interference of fatigue on daily activities over the past week. Response options are on a 5-point Likert scale, ranging from 1 (never) to 5 (always). A total score is obtained by summing the responses to the seven items [range 7 (never) to 35 (always)] and converting to a standardized T-score. The change from baseline in PROMIS Fatigue SF-7a Total Fatigue Score will be presented.
Measured: Up to approximately Week 52
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Jul 2026
- Study start29 Oct 2026
- Primary completion25 Jun 2032 (estimated)
- Study completion30 Nov 2032 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Polycythemia VeraStudies of the same condition, open and under way.
- More trials run by Merck Sharp & Dohme LLCThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
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 2/3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 380 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Merck Sharp & Dohme LLC
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Medical Director, Study director, Merck Sharp & Dohme LLC
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07722611
- Sponsor's protocol ID
- 3543-025
- Other IDs
- MK-3543-025, U1111-1335-3093, 2026-525630-38-00
- Status last verified
- Nov 2026
- First submitted
- 20 Jul 2026
- Last updated
- 5 Nov 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf
Study at a glance
From the registry record, last updated by the sponsor on 5 Nov 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 2/3, Randomized, Open-label, Active-comparator-controlled, Parallel-group, Multicenter Study to Evaluate the Safety and Efficacy of Bomedemstat (MK-3543) Versus Best Available Therapy in Participants With Polycythemia Vera Who Have an Inadequate Response to or Are Intolerant to Hydroxyurea
- ClinicalTrials.gov ID
- NCT07722611
- Acronym / sponsor ID
- 3543-025
- Conditions
- Polycythemia Vera
- Phase
- Phase 2/3
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 380 participants (estimated)
- Lead sponsor
- Merck Sharp & Dohme LLCIndustry (pharma, biotech, devices)
- Study start
- 29 Oct 2026 (actual)
- Primary completion
- 25 Jun 2032 (estimated)
- Study completion
- 30 Nov 2032 (estimated)
- First posted
- 23 Jul 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Researchers are looking for new ways to treat polycythemia vera (PV). People with PV may receive treatment to lower the number of red blood cells in the blood, but the usual treatments may not work for everyone. Researchers want to learn if a trial medicine called bomedemstat, also called MK-3543, can treat PV. In this study, researchers will compare bomedemstat to 2 usual treatments for PV.
The goal of this study is to learn if more participants who take bomedemstat reach healthy blood cell counts and avoid major health problems from PV, compared to those who receive a usual treatment.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Bomedemstat | Experimental | Drug: BomedemstatParticipants will receive bomedemstat daily for up to approximately 52 weeks. Per protocol, dosage may be adjusted within specified time parameters for each participant to achieve and maintain protocol-specified platelet and hematocrit target ranges. Eligible participants who do not discontinue study treatment at Week 52, may continue to receive study treatment. |
| Best Available Therapy (BAT) | Active comparator | Drug: Ruxolitinib, Drug: Ropeginterferon alfa-2bParticipants will receive either ropeinterferon alfa-2b or ruxolitinib as determined by investigator. All participants will be treated per respective approved product labels for up to approximately 52 weeks. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (11 listed)
- Has confirmed local diagnosis of polycythemia vera (PV) per World Health Organization (WHO) diagnostic criteria for PV
- Must have discontinued prior cytoreductive therapy for condition under study for protocol specified duration
- Has failed at least one prior line of cytoreductive therapy to lower hematocrit
- Has a history of inadequate response, resistance to, or intolerant to hydroxyurea (HU) per protocol specified criteria
- Has no evidence of splenomegaly and no symptoms attributable to splenomegaly, including early satiety, left upper quadrant discomfort, or splenic pain
Key exclusion criteria (8 listed)
- Has history of any illness/impairment of gastrointestinal (GI) function that might interfere with drug absorption
- Has evidence at the time of screening of increased risk of bleeding
- Has history of malignancy, unless potentially curative treatment has been completed with no evidence of malignancy for 2 years
- HIV-infected participants with a history of Kaposi's sarcoma and/or Multicentric Castleman's Disease
- Is currently receiving anticancer therapy
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| BomedemstatAlso: MK-3543, IMG-7289, Bomedemstat tosylateOral Capsule | Drug | Bomedemstat |
| RuxolitinibOral Tablet | Drug | Best Available Therapy (BAT) |
| Ropeginterferon alfa-2bSubcutaneous Solution | Drug | Best Available Therapy (BAT) |
Primary outcome
Clinicohematologic Response (CHR) Rate
Time frame: Up to approximately Week 52
CHR Rate is defined as all of the following: (i) a confirmed hematologic remission sustained for at least 12 consecutive weeks by Week 40 through Week 52, (ii) and absence of any of the following as assessed by the adjudication committee Week 52: thrombotic event; major hemorrhagic events; disease progression to myelofibrosis (MF) or myelodysplastic syndrome (MDS)/acute myeloid leukemia (AML). CHR will begin on the date of the first confirmed assessment achieving CHR criteria and will end on the earliest date of the following: 1) day of the first confirmed assessment not achieving CHR criteria, 2) date of first major hemorrhagic event or thrombotic event as assessed by the adjudication committee, or 3) disease progression as assessed by the adjudication committee. The CHR rate will be presented.
12 secondary outcomes
Clinicohematologic Response Sustained for a 24-Week Time Period (CHR24)
Time frame: Up to approximately Week 52
Number of Participants Who Experience an Adverse Event (AE)
Time frame: Up to approximately Week 52
Number of Participants Who Discontinue Study Treatment Due to an AE
Time frame: Up to approximately Week 52
Duration of Clinicohematologic Response Sustained for a 24-Week Time Period (DOCHR24)
Time frame: Up to approximately Week 52
Duration of Clinicohematologic Response (DOCHR)
Time frame: Up to approximately Week 52
Duration of Hematologic Remission (DOHR)
Time frame: Up to approximately Week 52
Number of Participants Who Experience Phlebotomies
Time frame: Up to approximately Week 52
Disease Progression Rate
Time frame: Up to approximately Week 52
Number of Participants Who Experience Thrombotic Events
Time frame: Up to approximately Week 52
Number of Participants Who Experience Major Hemorrhagic Events
Time frame: Up to approximately Week 52
Change From Baseline in Myelofibrosis Symptom Assessment Form version 4.0 (MFSAF v4) Total Symptom Score
Time frame: Up to approximately Week 52
Change From Baseline in Patient-Reported Outcomes Measurement Information System (PROMIS) Fatigue Short Form (SF) 7a Total Fatigue Score
Time frame: Up to approximately Week 52
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 5 Nov 2026.
- Individual participant dataSharing planned: Yes. https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf
Related trials for Polycythemia Vera
RecruitingPhase 3
A Phase 3 Study of Pelabresib (DAK539) and Ruxolitinib in Myelofibrosis (MF)
Primary Myelofibrosis (PMF), Post-polycythemia Vera Myelofibrosis (PPV-MF)
RecruitingPhase 2
Study of Momelotinib in Combination With Luspatercept in Participants With Transfusion Dependent Myelofibrosis
Primary Myelofibrosis, Myelofibrosis; Primary Myelofibrosis; Post-polycythemia Vera Myelofibrosis; Post-essential Thrombocythemia Myelofibrosis
RecruitingPhase 2
A Study of Ropeg-Interferon in People With Polycythemia Vera
Polycythemia Vera (PV), JAK2 Mutation
Active, not recruitingPhase 2
A Phase 2, Open-Label Study of DISC-3405 in Participants With Polycythemia Vera (PV)
Polycythemia Vera (PV)
RecruitingPhase 1
Study of INCA036978 in Participants With Myeloproliferative Neoplasms
Myeloproliferative Neoplasms
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Medical Director study director
Merck Sharp & Dohme LLC
5 sites in 3 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2/3 study testing Bomedemstat, Ruxolitinib and Ropeginterferon alfa-2b in people with Polycythemia Vera, run by Merck Sharp & Dohme LLC at 5 sites in 3 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 11 inclusion and 8 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 5 Nov 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 5 sites in United States, Canada, Israel. 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 combined phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
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?
Clinicohematologic Response (CHR) Rate (time frame: Up to approximately Week 52). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 5 Nov 2026.