A Phase 4 interventional study of Momelotinib and Ruxolitinib in Myelofibrosis and Myelofibrosis (MF), sponsored by SWOG Cancer Research Network. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-17.
Sponsored by SWOG Cancer Research Network · Phase 4, Interventional, and Treatment
Among 12 studies testing momelotinib in Primary Myelofibrosis — 3 open to participants now, 4 under way, none of them phase 3. momelotinib · Primary Myelofibrosis.
Among the 12 studies testing momelotinib in Primary Myelofibrosis, this one is the 2nd largest by planned enrollment, is one of 2 that started in 2026, is the only one in phase 4, and was the 12th registered.
625 studies on the registry are indexed under Primary Myelofibrosis; 124 are open to participants now.
Browse Primary Myelofibrosis studies →3 of the 12 studies testing momelotinib in Primary Myelofibrosis are open now, in 6 countries. Recruiting first, the newest first:
Massachusetts General Hospital · Sites in United States
GlaxoSmithKline · Sites in United States, Canada, France and 3 more countries
By country, each count listing its studies:
momelotinib: first FDA approval 2023 (OJJAARA), first EMA approval 2024. What it is approved for, and how studies give it, is on its page →
Of the 101 Primary Myelofibrosis studies recruiting now, 83 (82%) set no upper age limit and 13 (13%) stop at 75 or younger; 10 take children under 18; 7 take healthy volunteers.
This study: 18 Years and older · all sexes · no healthy volunteers.
The full table on the hub →This tab as a report to print or save as PDF → With an account.
12 studies; the count open now beside each. This study's row is marked.
A study in two phases is counted once above. Listed by phase, each with its combined phases: Phase 1 3 · Phase 2 7 · Phase 3 3 · Phase 4 1
First in 2009; this study’s year is marked. 2 started in 2026.
This study's planned enrollment of 268 is above the median of 43 across 489 interventional studies indexed under Primary Myelofibrosis.
Median enrollment 138 across the 12 interventional studies. Of the 8 that completed or were terminated, 5 (63%) have results posted.
This tab as a report to print or save as PDF → With an account.
10 of 12 have an industry lead sponsor. The 4 most frequent:
SWOG Cancer Research Network is the lead sponsor of 339 studies on the registry; 37 are open to participants now.
Of its 17 completed or terminated interventional studies of FDA-regulated products, 17 (100%) have results posted.
SWOG Cancer Research Network has 1 study filed under Primary Myelofibrosis — fewer than ten, so there is no comparison to draw.
2 of the studies testing momelotinib in Primary Myelofibrosis that are under way reach primary completion within a year, 0 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT03441113GlaxoSmithKlineExtended Access of Momelotinib in Adults With Myelofibrosis | 2026-12-11 |
| NCT06517875GlaxoSmithKlineStudy of Momelotinib in Combination With Luspatercept in Participants With Transfusion Dependent Myelofibrosis | 2027-03-16 |
Among the 12 studies testing momelotinib in Primary Myelofibrosis, from their registry updates:
This tab as a report to print or save as PDF → With an account.
The purpose of this study is to compare momelotinib and ruxolitinib as treatments for myelofibrosis with low blood cell counts. Both drugs are approved by the FDA to treat myelofibrosis. The study asks which drug does a better job at shrinking the spleen.
This study is being done to answer this question:
Does momelotinib or ruxolitinib do a better job at shrinking the spleen in people who have myelofibrosis with low blood cell counts and haven't been treated yet?
Other goals of this study are to find out:
Momelotinib and ruxolitinib are JAK inhibitors. JAK inhibitors are medicines that block a type of protein that can cause the immune system to be too active, which can cause pain and swelling (including in the spleen). JAK inhibitors are the most commonly used drugs for myelofibrosis that has caused serious symptoms including swelling in the spleen.
There are many different JAK inhibitors approved by the FDA to treat myelofibrosis, but no previous studies have compared these drugs with each other for treating myelofibrosis in people with low blood cell counts who haven't been treated yet.
Registration Step 1: Randomization
Inclusion Criteria:
Exclusion Criteria:
Registration Step 2: Optional Crossover for All Participants after Week 24 Assessment
Inclusion Criteria:
Participants must have met one or more of the following criteria on Registration Step 1:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
A “mini-stroke”: temporary stroke-like symptoms caused by reduced blood flow to part of the brain, spinal cord or eye, without signs of a new stroke on a scan.
Stroke symptoms need emergency care at once, even if they go away.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Able to have children. For women this usually means from the first period until menopause, unless permanently unable to through surgery; for men, unless permanently sterile. Read who the line is about — participants, women, men, or their partners.
Criteria about it usually ask for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Creatinine clearance (CrCl)
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Allogeneic and autologous transplant
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Live vaccines
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
NYHA class (heart failure)
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
TIA (transient ischaemic attack)
A “mini-stroke”: temporary stroke-like symptoms caused by reduced blood flow to part of the brain, spinal cord or eye, without signs of a new stroke on a scan.
Stroke symptoms need emergency care at once, even if they go away.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Reproductive potential
Able to have children. For women this usually means from the first period until menopause, unless permanently unable to through surgery; for men, unless permanently sterile. Read who the line is about — participants, women, men, or their partners.
Criteria about it usually ask for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Momelotinib
Drug: Momelotinib
Ruxolitinib
Drug: Ruxolitinib
200 mg daily x 96 weeks.
Also known as: JAK-inihibitor
Twice daily per treating investigator discretion not to exceed protocol specified guidelines.
Also known as: JAK-inihibitor
To estimate and compare the proportion of participants achieving a dual response [SVR35] and transfusion independence response from red blood cell transfusions.
To estimate and compare the proportion of patients 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.
Time frame: 24 weeks after randomization
TI-R Rate
To estimate and compare the TI-R rate at week 24, post-Step 1 randomization in each treatment arm.
Time frame: 24 weeks after Step 1 Randomization
SVR35 at week 24 post-randomization
To estimate and compare the rates of SVR35 at week 24 post-randomization in each treatment arm.
Time frame: 24 weeks after Step 1 Randomization
OS
To estimate overall survival (OS) in each treatment arm.
Time frame: 96 weeks after Step 1 Randomization
PFS
To estimate progression-free survival (PFS) in each treatment arm.
Time frame: 96 weeks after Step 1 Randomization
SVR35 at week 24 post-randomization
To estimate and compare SVR35 at week 24 post-randomization in each treatment arm with a sensitivity analysis based on a modeled version of the continuous spleen response rate.
Time frame: 24 weeks after Step 1 Randomization
Allogeneic Transplantation
To tabulate the proportion of participants in each arm who undergo allogeneic transplantation at week 24 and week 48 post-Step 1 randomization.
Time frame: 96 weeks after Step 1 Randomization
Cross-over
To tabulate the number of participants on each arm who cross over.
Time frame: 72 weeks after Step 1 Randomization
Time to next non-protocol treatment
To estimate and compare the time to next non-protocol treatment (excludes crossover) in each treatment arm.
Time frame: 96 weeks after Step 1 Randomization
SVR35
To estimate and compare the rates of SVR35 at week 48 post-Step 1 randomization by treatment arm and stratified by cross-over-status.
Time frame: 48 weeks after Step 1 Randomization
TI-R
To estimate and compare the rates of TI-R at week 48 post-Step 1 randomization by treatment arm and stratified by cross-over-status.
Time frame: 48 weeks after Step 1 Randomization
Dual Response
To estimate and compare the rates of dual response (SVR35 + TI-R) at week 48 post-Step 1 randomization by treatment arm and stratified by cross-over-status.
Time frame: 48 weeks after Step 1 Randomization
To estimate the frequency of and severity of toxicities in each treatment arm
To estimate and compare the frequency of major anemia response per 2024 IWG-ELN criteria in each treatment arm by week 24 and by week 48 (week 48 stratified by cross-over-status).
Time frame: 48 weeks after Step 1 Randomization
Major anemia response
To estimate and compare the frequency of major anemia response per 2024 IWG-ELN criteria in each treatment arm by week 24 and by week 48 (week 48 stratified by cross-over-status).
Time frame: 48 weeks after Step 1 Randomization
Time to initiation of anemia-directed therapy
To estimate and compare the time to initiation of anemia-directed therapy in each treatment arm among participants not on anemia-directed therapy at registration by week 24 and by week 48 (week 48 stratified by cross-over-status).
Time frame: 48 weeks after Step 1 Randomization
Symptom Burden
To compare symptom burden by arm at week 24 using the Myelofibrosis Symptom Assessment Form version 4.0 (MF-SAF v4.0) total score and the Functional Assessment of Cancer Therapy - Anemia (FACT-An) total score
Time frame: 96 weeks after Step 1 Randomization
MF-SAF Scores
To compare by arm individual item scores from the MF-SAF v4.0.
Time frame: 96 weeks after Step 1 Randomization
FACT-An Scores
To compare by arm individual item subscale scores from the FACT-An.
Time frame: 96 weeks after Step 1 Randomization
Longitudinal Trajectories
To examine by arm differences in longitudinal trajectories over time in the MF-SAF v4.0 total score, the FACT-An total score, and MF-SAF v4.0 item scores and FACT-An subscale scores.
Time frame: 96 weeks after Step 1 Randomization
Specimen Banking
To bank specimens for future correlative studies.
Time frame: 96 weeks after Step 1 Randomization
No study locations are listed for this record.
Plan to share: No
No publications or documents are linked to this record.
Start is estimated for Nov 2026; primary completion for Aug 2029, 33 months later.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
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Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Studies of the drugs tested here: Momelotinib · Ruxolitinib
SWOG Cancer Research Network →