A study testing two targeted medicines, bomedemstat, which helps normalise blood cell development, and momelotinib, which reduces symptoms and anaemia, to see whether the combination is safe and effective for people with myelofibrosis

ISRCTN	ISRCTN98283910
DOI	https://doi.org/10.1186/ISRCTN98283910
Sponsor	United Lincolnshire Hospitals NHS Trust
Funder	MSD Sharp and Dohme

Submission date: 12/02/2026
Registration date: 16/02/2026
Last edited: 16/02/2026

Recruitment status: Not yet recruiting
Overall study status: Ongoing
Condition category: Cancer

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Record updated in last year

Plain English summary of protocol

Background and study aims
This is an open-label, single-arm, phase II interventional study designed to evaluate the safety and efficacy of bomedemstat (IMG-7289) when added to momelotinib in patients with myelofibrosis (MF) who exhibit a suboptimal response to momelotinib alone or who present with baseline cytopenias and do not achieve adequate improvement after 12 weeks of momelotinib monotherapy.

Who can participate?
Patients aged 18 years and over with MF.

What does the study involve?
The study consists of three phases:
1. Screening Phase (up to 28 days)
2. Momelotinib Monotherapy Phase — Weeks 0–12
3. Combination Treatment Phase (Momelotinib + Bomedemstat) — Weeks 12–24
4. Post-Treatment Follow-up Phase (30 days post last dose + long-term survival follow-up)
All patients will continue on Momelotinib throughout the study unless toxicity or safety considerations necessitate modification.

What are the possible benefits and risks of participating?
Benefits and risks not provided at time of registration

Where is the study run from?
United Lincolnshire Hospitals NHS Trust, UK.

When is the study starting and how long is it expected to run for?
November 2026 to November 2029.

Who is funding the study?
MSD Sharp and Dohme GmbH.

Who is the main contact?
Prof Ciro Rinaldi, crinaldi@lincoln.ac.uk

Contact information

Prof Ciro Rinaldi
Public, Scientific, Principal investigator

Lincoln County Hospital
Greetwell Road
Lincoln
LN2 5QY
United Kingdom

Phone	+44 07720373877
Email	crinaldi@nhs.net

Study information

Primary study design	Interventional
Allocation	N/A: single arm study
Masking	Open (masking not used)
Control	Uncontrolled
Assignment	Single
Purpose	Treatment
Scientific title	Study to assess the safety and efficacy of bomedemstat (IMG-7289) in combination with momelotinib in patients with myelofibrosis
Study objectives	Myelofibrosis is a disease with heterogeneous driver pathways involving JAK-STAT activation, inflammatory cytokine signaling, and aberrant megakaryopoiesis. Momelotinib targets JAK1/JAK2 and ACVR1, improving anemia and splenomegaly. However, a proportion of patients fail to achieve adequate spleen, symptom, or hematologic improvement. Bomedemstat, an irreversible LSD1 inhibitor, may: • Modify megakaryocyte function • Reduce fibrosis • Improve cytokine dysregulation • Impact stem/progenitor dynamics Sequential introduction of Bomedemstat at Week 12 allows assessment of Momelotinib’s initial stabilizing effect and evaluates whether LSD1 inhibition can rescue suboptimal responders without compromising hematologic tolerability.
Ethics approval(s)	Not yet submitted
Health condition(s) or problem(s) studied	Myelofibrosis
Intervention	Screening (≤ 28 days) ↓ Momelotinib Alone (Weeks 0–12) ↓ Week 12 Response Assessment If Suboptimal → Add Bomedemstat 50 mg QD ↓ Combination Phase (Weeks 12–24) ↓ Week 24 Primary Endpoint Assessment ↓ Safety Follow-Up (30 days post last dose) ↓ Long-Term Follow-Up (q12 weeks for 12 months)
Intervention type	Drug
Phase	Phase II
Drug / device / biological / vaccine name(s)	Bomedemstat, momelotinib
Primary outcome measure(s)	Spleen volume reduction ≥35% (SVR35) measured using MRI, or CT if patients cannot tolerate MRI, at week 24
Key secondary outcome measure(s)
Completion date	01/11/2029

Eligibility

Participant type(s)
Age group	Mixed
Lower age limit	18 Years
Upper age limit	99 Years
Sex	All
Target sample size at registration	40
Total final enrolment	40
Key inclusion criteria	1. Male or female participants ≥18 years of age on the day of signing informed consent. 2. Histologically confirmed diagnosis of: 2.1. Primary Myelofibrosis (PMF), or 2.2. Secondary MF following Polycythaemia Vera (post-PV MF), or 2.3. Secondary MF following Essential Thrombocythaemia (post-ET MF) (as defined by WHO 2022 criteria) 3. Disease risk category: 3.1. Intermediate-2 or High-risk MF according to DIPSS. 4. Cohort assignment (Investigator-defined; permitted insertion): 4.1. Cohort 1 — Momelotinib-Experienced: 4.1.1. Receiving Momelotinib 200 mg QD for ≥12 weeks prior to Week 12 assessment 4.1.2. Demonstrates suboptimal response at Week 12 4.2. Cohort 2 — Cytopenic MF: 4.2.1. Baseline Hb <10 g/dL and/or platelets <100 × 10⁹/L 4.2.2. Starting Momelotinib at Week 0 4.2.3. Demonstrates suboptimal response at Week 12
Key exclusion criteria	1. Medical Conditions 1.1. Known hypersensitivity to Bomedemstat or MAOIs 1.2. Clinically significant GI conditions affecting absorption 1.3. Increased bleeding risk 1.4. Hereditary bleeding disorders 1.5. Active or chronic bleeding within 8 weeks 1.6. Autoimmune bleeding disorders 1.7. Uncontrolled comorbidities 1.8. Active secondary malignancies (with exceptions) 1.9. HBV/HCV/HIV status not meeting template criteria 1.10. Receipt of prohibited medications within 14 days 2. Prohibited Prior Therapies 2.1. Prior treatment with Bomedemstat or other LSD1 inhibitors 2.2. MAOIs or strong CYP3A4 modifiers 2.3. All hematopoietic growth factors (G-CSF, GM-CSF, EPO, TPO mimetics) 2.4. Investigational treatments within 4 weeks Investigator addition permitted: 2.5. Prior treatment with Momelotinib is allowed for Cohort 1 (required) 2.6. Prior treatment with Momelotinib is allowed for Cohort 2 (not required) 2.7. Prior exposure to other JAK inhibitors (e.g., ruxolitinib, fedratinib) is allowed unless associated with severe toxicity 3. Prohibited During Study (Verbatim text from first file retained) 3.1. MAOIs 3.2. Strong inhibitors/inducers of CYP3A4 3.3. Anticoagulants/antiplatelets/NSAIDs when platelets <100 ×10⁹/L
Date of first enrolment	01/11/2026
Date of final enrolment	01/11/2028

Locations

Countries of recruitment

United Kingdom
England
France
Spain
United Arab Emirates
United States of America

Study participating centre

United Lincolnshire Teaching Hospitals NHS Trust

Lincoln County Hospital
Greetwell Road
Lincoln
LN2 5QY
England

Results and Publications

Individual participant data (IPD) Intention to share	No
IPD sharing plan summary	Not expected to be made available
IPD sharing plan

Editorial Notes

16/02/2026: Study’s existence confirmed by the United Lincolnshire Hospitals NHS Trust, UK.