Phase 2
N=81
An Extension Study of Bomedemstat (IMG-7289/MK-3543) in Participants With Myeloproliferative Neoplasms (IMG-7289-CTP-202/MK-3543-005)
Thrombocythemia, Essential · Primary Myelofibrosis
Bottom Line
View on ClinicalTrials.gov: NCT05223920 ↗Enrolled (actual)
81
Serious AEs
38.3%
Results posted
Sep 2025
Primary outcome: Primary: Percentage of Participants Who Experience an Adverse Event (AE) — 98.1; 100.0 Percentage of Participants
Study Design & Population
- Study type
- Interventional
- Phase
- Phase 2
- Interventions
- Bomedemstat (Drug)
- Age
- Adult, Older Adult · 18+ yrs
- Sex
- All
- Sponsor
- Imago BioSciences, Inc., a subsidiary of Merck & Co., Inc., (Rahway, New Jersey USA)
- Primary completion
- Aug 2024
Outcome Measures
| Outcome | Result | p-value |
|---|---|---|
| PRIMARY Percentage of Participants Who Experience an Adverse Event (AE) |
98.1; 100.0 | — |
| PRIMARY Percentage of Participants Who Discontinue Study Intervention Due to an AE |
15.4; 10.3 | — |
| PRIMARY Mean Spleen Volume Reduction Based on Spleen Volume Measured by MRI in Participants With MF. |
-101.570; -67.645; -5.920; -61.000; -38.840; 80.575 | — |
| PRIMARY Percentage of Participants With ET Who Achieve a Reduction of Platelet Counts to <= 400 K/uL (400 x 10^9/L) in the Absence of New Thromboembolic Events |
77.1; 72.9; 72.0; 78.4; 91.8; 89.4 | — |
Summary
This is a multi-center, open-label extension study to assess the long-term safety and efficacy of bomedemstat administered orally once daily in participants with a Myeloproliferative Neoplasm (MPN) who participated in a prior bomedemstat study such as, but not limited to, IMG-7289-CTP-102/MK-3543-002 (NCT03136185) and IMG-7289-CTP-201/MK-3543-003 (NCT04254978) (referred to hereafter as 'feeder studies').
Eligibility Criteria
Inclusion Criteria
Inclusion Criteria include, but are not limited to:
- Has completed at least one Treatment Period (TP) in a prior bomedemstat Myeloproliferative Neoplasms (MPN) protocol (such as, but not limited to, IMG-7289-CTP-102/MK-3543-002 (NCT03136185) and IMG-7289-CTP-201/MK-3543-003) (NCT04254978).
- In the estimation of the Investigator, the risk-benefit favors continued dosing with bomedemstat.
Exclusion Criteria
Exclusion Criteria include, but are not limited to:
- Ongoing participation in another investigational study (except observational studies).
- A history of non-compliance in a prior bomedemstat study (excluding dose suspensions that were medically warranted).
- Current use of a prohibited medication (e.g., romiplostim).
- Medical, psychiatric, cognitive, or other conditions that, in the Investigator's opinion, compromise the patient's safety, ability to give informed consent, or comply with the trial protocol.
- Is pregnant or breastfeeding or plan to become pregnant or breastfeed during the study.
- Women of childbearing potential (WOCBP) and fertile men unwilling to agree to use an approved method of contraception from time of enrollment until 14 days after last bomedemstat dose.
Data sourced from ClinicalTrials.gov (NCT05223920). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.