APEX-MF, A RANDOMIZED OPEN LABEL TRIAL COMPARING MOMELOTINIB VS DOSE-ADJUSTED RUXOLITINIB FOR TREATMENT-NAÏVE, CYTOPENIC MYELOFIBROSIS

Alexander Coltoff, MD
Aaron T. Gerds, MD
Uma M. Borate, MD, MS
Xueyan Chen, MD, PhD
26CTP.LEUK02 Study Chairs

ACTIVATED: 6/26/2026

For sites that are members of the SWOG Cancer Research Network ONLY:
If your site is interested in applying to open this study, please complete the feasibility questionnaire. It collects essential information to help us assess each site’s suitability for the study.

26CTP.LEUK02 STUDY SYNOPSIS

Schema

26CTP.Leuk02 schema
Schema Notes:
A    Maximum duration of study treatment is 96 weeks
B    Crossover may occur between 24-36 weeks post-Step 1 Registration. After crossover, new agent may be given for up to 72 weeks, provided  combined duration of momelotinib and ruxolitinib treatment ≤ 96 weeks.
C   Hemoglobin < 10 g/dL and platelet count 50-200 x 103/uL
D    Randomization is 2:1 (momelotinib:ruxolitinib)

Objective
  • To estimate and compare the proportion of participants achieving a dual response (both spleen response [SVR35] and transfusion independence response [TI-R] from red blood cell transfusions) at week 24 post-Step 1 randomization in JAK-inhibitor naïve participants with myelofibrosis treated with momelotinib versus ruxolitinib.
Key Eligibility

Inclusion Criteria

  1. Diagnosis of primary myelofibrosis (PMF), post-polycythemia vera (PV) MF, or post-essential thrombocythemia (ET) MF per 2022 WHO classification, confirmed by bone marrow biopsy within 4 years
  2. Spleen ≥ 450 cm3 by MRI w/in 14 days prior to registration (or by CT if MRI is contraindicated or unavailable)
  3. DIPSS risk category of Intermediate-1, Intermediate-2, or High
  4. Blasts <10% in peripheral blood (and in bone marrow biopsy, if performed) within 28 days of registration
  5.  ≥ 18 years old w performance status 0-2
  6. Within 28 days prior to registration:
    1. Complete medical history and physical exam
    2. Platelets 50 – 200 x 103/uL
    3. Hemoglobin < 10 g/dL
    4. Calculated creatinine clearance ≥ 30mL/min per Cockcroft-Gault Formula

Exclusion Criteria

  1. No drugs to treat MF within 14 days prior to registration
  2. Not eligible for hematopoietic stem cell transplantation (HSCT) or had prior HSCT for MF
  3. No prior JAK or ACVR1 inhibitor treatment
  4. No investigational therapy within 14 days prior to registration
  5. No prior splenectomy
  6. No splenic irradiation within 90 days prior to registration
  7. No prior chemotherapy for MF
  8. No major surgery within 21 days prior registration
  9. No live vaccine within 14 days prior to registration
  10. No grade 2 or higher peripheral neuropathy
  11. If history of HIV infection, on effective anti-retroviral therapy at registration, with undetectable viral load on most recent test within 6 months prior to registration
  12. If history of HBV infection, undetectable viral load while on suppressive therapy on most recent test within 6 months prior to registration
  13. If history of HCV infection, must have been treated and cured or, if being currently treated, have undetectable viral load on most recent test within 6 months prior to registration
  14. No clinically significant cardiac disease, symptomatic congestive heart failure, or unstable angina pectoris
  15. No impairment of GI function, nor GI disease that may significantly alter absorption of study drugs
  16. No history of stroke, reversible ischemic neurologic deficit, or transient ischemic attack within 90 days prior to registration
  17. No prior or concurrent malignancy whose natural history or treatment has potential to interfere with safety or efficacy assessment of the study investigational regimen
  18. No uncontrolled systemic fungal, bacterial, viral, or other infection
  19. Must not be pregnant or nursing

Study Calendar

This study calendar is based on the May 20, 2026 protocol version. Always refer to the latest IRB-approved protocol.

Study Calendar Footnotes:
NOTE: Forms are found on the SWOG website (swog.org). The schedule for submission of these forms is listed in Protocol Section 14.4.
A. Institutional standard metabolic panel is sufficient, provided it includes total bilirubin, AST and ALT, serum creatinine and alkaline phosphatase.
B. Intake calendar shall be reviewed at monthly visits (optional).
C. Please see Section 5.1.c, to be completed if clinically indicated
D. A historical bone marrow biopsy (within 4 years of Step 1 registration) may be used to confirm diagnosis, provided that clinical and/or laboratory assessments demonstrate no evidence of disease progression since the time of the prior biopsy (see Section 5.1.a.1).
E. CT/MRI to be done per Section 7.5 disease assessments. Imaging modality must remain the same throughout study conduct.
F. Assessments should continue every 4 weeks until resolution of all acute adverse events.
G. See Section 15.4.
H. Participants should be evaluated every four weeks.
I. To be completed every 4 weeks.
J. Participants must have in-person clinic visits every 12 weeks.
K. Physical exam to be completed during each in-person clinic visit every 12 weeks.
L. Pregnancy testing is only required for participants of childbearing potential.
M. Participants have the option of enrolling to Step 2 registration for crossover to the alternate treatment arm provided they meet eligibility criteria per Section 5.2.
N. CMP and CBC are only needed at optional crossover if not completed within 14 days of Step 2 registration.

Specimen Collection

Specimen Collection Footnotes:
A. Specimen collection will be conducted per the outlined timepoints or at the end of treatment. No collections will be performed after end of treatment.
B. See processing instructions in Protocol Section 15.2. Frozen serum is submitted to the SWOG Biospecimen Bank.
NOTE: Per SWOG Best Practices, specimens can be collected +/- 7 days from regular treatment interval except where noted for Baseline.
NOTE: A table of all specimen requirements is accessible via the SWOG Specimen Tracking System (https://spectrack.crab.org/Logon.aspx) under Reports >> Specimen Requirements Summary. Here, specimen requirements can be sorted or filtered online by Timepoint, Specimen Type, and Lab (or Biospecimen Bank) or downloaded into an MS Excel file for site use.

Funding Memo

* Pre-Activation Checklist:

  • Form FDA 1572
  • DTL (Delegation of Tasks Log)
  • CVs (curriculum vitae)
  • FDFs (Financial Disclosure Forms)
  • Medical Licenses
  • GCP Training Certs.
  • Florence Training Certs.
  • Site Signature Page
  • CTEP ID Page

 

Study Contact Information

Funding Questions:
[email protected]

Protocol Questions Contact:
[email protected]

Medical Questions:
[email protected]

Eligibility and Data Questions:
[email protected]