A Phase 2/3 interventional study of Momelotinib and Glucocorticoids in VEXAS Syndrome, sponsored by GlaxoSmithKline. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-06-01.
Sponsored by GlaxoSmithKline · Phase 2/3, Interventional, and Treatment
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This study will assess the efficacy and safety of momelotinib in participants with a diagnosis of VEXAS.
GlaxoSmithKline is the lead sponsor of 3,650 studies on the registry; 117 are open to participants now.
Of its 265 completed or terminated interventional studies of FDA-regulated products, 241 (91%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Confirmed diagnosis of clinical VEXAS defined by:
A female participant is eligible to participate if she is not pregnant or breastfeeding and one of the following conditions applies:
Exclusion Criteria:
Use of the following treatments within the noted time periods referenced from date of randomization:
Any of the following conditions within 6 months prior to randomization:
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.
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.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and 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.
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.
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.
The US National Cancer Institute’s scale of how severe an adverse event is — any unwanted medical event during a study, such as a symptom, an illness or an abnormal test result, whether or not a treatment caused it. Whether it did is judged separately.
“Side effects of earlier treatment resolved to grade 1 or less” means they have settled to mild or gone.
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.
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.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
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.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
A planned gap after a treatment, so that its effects can lessen before the study treatment or a study assessment. Ask the study team and the doctor who prescribed it before changing any medicine.
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.
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
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.
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
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.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and 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.
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.
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.
CTCAE grade
The US National Cancer Institute’s scale of how severe an adverse event is — any unwanted medical event during a study, such as a symptom, an illness or an abnormal test result, whether or not a treatment caused it. Whether it did is judged separately.
“Side effects of earlier treatment resolved to grade 1 or less” means they have settled to mild or gone.
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.
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.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
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.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Washout period
A planned gap after a treatment, so that its effects can lessen before the study treatment or a study assessment. Ask the study team and the doctor who prescribed it before changing any medicine.
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.
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.
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.
QT and QTc
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive momelotinib at dose level 1 along with glucocorticoids as a background therapy (prednisone or prednisolone). Due to adaptive design of the study, additional participants may be randomized to this arm in phase 3.
Drug: Momelotinib · Drug: Glucocorticoids
Participants will receive momelotinib at dose level 2 along with glucocorticoids as a background therapy (prednisone or prednisolone). Due to adaptive design of the study, additional participants may be randomized to this arm in phase 3
Drug: Momelotinib · Drug: Glucocorticoids
Participants will receive momelotinib matched placebo along with glucocorticoids as a background therapy(prednisone or prednisolone). Due to adaptive design of the study, additional participants may be randomized to this arm in phase 3
Drug: Glucocorticoids · Drug: Placebo
Momelotinib will be administered
Also known as: GSK3070785
Glucocorticoids (prednisone or prednisolone) will be administered
Placebo will be administered
ORR (Objective response rate) at Week 26
ORR is defined as the proportion of participants who have achieved complete response (CR) or partial response (PR) during the 26-week Primary Treatment Period.
Time frame: At Week 26
Phase 2: Percentage of participants with partial response (PR) or complete response (CR) at Week 26
Percentage of participants with PR or CR at Week 26 to support identification of the Recommended Phase 3 dose (RP3D)
Time frame: At Week 26
Phase 2: Number of participants with adverse events and clinically significant changes in laboratory parameters, and vital signs to support identification of the RP3D
Time frame: Up to 26 Weeks
Phase 2: Plasma concentrations of momelotinib and metabolite of momelotinib 21 (M21) to support identification of the RP3D
Time frame: Up to 26 Weeks
Number of flare-free days
Flare-free days are calendar days without clinical evidence of VEXAS flare and without treatment escalation. Total number of flare-free days is defined as the cumulative number of consecutive and non-consecutive flare-free days.
Time frame: Up to 26 Weeks
Duration of response (DoR)
DoR defined as the date of clinical response (CR or PR) to the date of relapse.
Time frame: Up to 104 Weeks
Number of flare-free days with glucocorticoid (GC) dose <=10 mg/day
Flare-free days are calendar days without clinical evidence of VEXAS flare and without treatment escalation. Total number of flare-free days is defined as the cumulative number of consecutive and non-consecutive flare-free days.
Time frame: Up to 104 Weeks
Percentage of participants achieving complete and partial biochemical response
Complete biological response is defined as complete or partial normalization of C-reactive protein.
Time frame: Up to 26 Weeks
Objective response rate (ORR) at Week 52
ORR is defined as the proportion of participants who have achieved complete response or partial response
Time frame: At Week 52
Number of Participants with Hematologic Improvement- Erythroid (HI-E) response per International Working Group (IWG) 2018 criteria
HI-E response is measured based on the combined incidence of: Low transfusion burden participants defined as absence of any transfusion for greater than or equal to (\>=)8 consecutive weeks. High transfusion burden participants: minor response defined as reduction by \>=50% of red blood cell (RBC) units for \>=8 consecutive weeks. Major response defined as absence of RBC transfusions for \>=8 consecutive weeks or longer up to 26 weeks.
Time frame: Up to 26 Weeks
Change from Baseline in Short Form 36 (SF-36) domain and summary scores
Short-Form 36 is a health-related survey that assesses quality of life covering 8 domains: vitality; physical functioning; bodily pain; general health perceptions; physical role functioning; emotional role functioning; social role functioning; and mental health. The domain scores are weighted to a scale ranging between 0 to 100, where higher score represents better health. The Physical Component Summary (PCS) and Mental Component Summary (MCS) scores are derived from the eight domain scores. These scores are standardized to a general U.S. population average of 50, with a standard deviation of 10. For both PCS and MCS, scores range from 0 to 100, higher scores indicate a better health outcome.
Time frame: Baseline and up to Week 48
Change from Baseline in European Organization for Research and Treatment of Cancer Item Library (EORTC IL) 479 score
The EORTC Item Library is a database containing \>1000 individual items from more than 70 EORTC quality of life measures. A subset of 7 items from the library were selected based on symptoms experienced by participants with VEXAS syndrome. Scores range from 1 to 100 with higher scores representing a higher ("worse") level of symptoms.
Time frame: Baseline and up to Week 156
Change From Baseline in Patient Reported Outcome Measurement Information System (PROMIS) Physical Function Short Form 10b
PROMIS Physical Function Short Form 10b consists of 10 questions; each with a 5-point response. PROMIS short form assesses self-reported capability of a participant rather than actual performance of physical activities. Higher scores indicate better functioning. Total possible range of scores is 10 to 50, with higher scores corresponding to a greater physical function ability.
Time frame: Baseline and up to Week 156
Change from Baseline in Functional Assessment of Chronic Illness Therapy - Fatigue (FACIT-FATIGUE)
The FACIT-Fatigue is a short, 13-item questionnaire that assesses self-reported fatigue and its associated impact on daily activities over the past 7 days. A higher score indicates a better outcome (no fatigue). The total score ranges from 0 to 52, with 0 being the worst possible score and 52 being the best possible score (indicating no fatigue).
Time frame: Baseline and up to Week 156
Changes from Baseline in Patient Global Impression of Severity (PGIS) scores
The PGIS is a single global question which asks participants to rate the severity of their VEXAS syndrome symptoms on a 5-point rating scale with response categories of "No symptoms", "Mild", "Moderate", "Severe", and "Very Severe." The PGIS scores ranges from 0 (absent) to 4 (very severe).
Time frame: Baseline and up to Week 156
Changes in Patient Global Impression of Change (PGIC) scores
The PGIC is a single global question which asks participants to rate the change in severity of their VEXAS syndrome symptoms since starting study medication using a 5-point rating scale with response categories of "much better", "a little better", "no change", "a little worse", "much worse". The PGIC score ranges from +2 (much better) to -2 (much worse).
Time frame: Baseline and up to Week 156
Changes from Baseline in European quality of life 5 dimensions 5 level version (EQ-5D-5L)
EQ-5D-5L is self-assessment questionnaire, consisting of 5 items covering 5 dimensions (mobility, self care, usual activities, pain/discomfort, and anxiety/depression). Each dimension is measured by 5-point Likert scale ranging from 1=no problems to 5=extreme problems.
Time frame: Baseline and up to Week 48
Changes from Baseline in European quality of life-Visual Analogue Scale (EQ-VAS)
The EQ-VAS records the respondents self-rated health on a vertical VAS, ranging from 0 to 100, where 0 represents the worst imaginable health and 100 represents the best imaginable health.
Time frame: Baseline and up to Week 48
Number of participants with adverse events (AEs) and Serious adverse events (SAEs)
Time frame: Up to Week 108
Number of participants with adverse events (AEs) and Serious adverse events (SAEs) by severity
Time frame: Up to Week 108
Number of participants with AEs leading to discontinuation or dose modifications
Time frame: Up to Week 108
Plasma concentration of momelotinib and M21
Time frame: Up to 26 Weeks
Overall Survival
Overall survival is defined as the time from randomization to the date of death due to any cause.
Time frame: At Months 12, 24 and 36
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 Aug 2026; primary completion for Dec 2028, 28 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 May 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Momelotinib
VEXAS syndrome