A Phase 2 interventional study of Arumakimig and Placebo in VEXAS Syndrome, sponsored by Novartis Pharmaceuticals. Recruiting at 6 sites in Japan. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-11-09.
Sponsored by Novartis Pharmaceuticals (part of Novartis) · Phase 2, Interventional, and Treatment
The purpose of this study is to evaluate clinical efficacy and safety of arumakimig (MAS825) compared to placebo in patients with Vacuoles, E1 Enzyme, X-linked, Autoinflammatory, Somatic (VEXAS) syndrome. In addition, the study will evaluate the long-term efficacy, safety and tolerability of arumakimig in this population.
This is a randomized, double-blind, placebo-controlled study with a 52-week duration evaluating the efficacy and safety of arumakimig in participants with VEXAS who are receiving glucocorticoids. Participants will be randomized 1:1 to either arumakimig or placebo.
Following the double-blind period, participants may have the option to enter a 2-year (104-week) open-label extension (OLE) period, continuing until Week 156.
A 16-week safety follow-up period must be completed after the OLE (up to Week 172) or after the double-blind period (up to Week 68).
843 studies on the registry are indexed under Arthritis; 118 are open to participants now.
This study's planned enrollment of 120 is above the median of 97 across 599 interventional studies indexed under Arthritis.
Browse Arthritis studies →Novartis Pharmaceuticals is the lead sponsor of 2,718 studies on the registry; 221 are open to participants now.
Of its 585 completed or terminated interventional studies of FDA-regulated products, 438 (75%) 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.
Exclusion Criteria:
HBsAg negative participants who are hepatitis B core antibody (HBcAb) positive are also excluded unless protocol-defined criteria are met.
Other protocol-defined inclusion/exclusion criteria may apply.
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.
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.
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 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.
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.
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.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
A score of how well the liver works in people with liver disease such as cirrhosis: class A is mild, B moderate and C severe.
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.
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.
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.
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.
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.
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.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Child-Pugh class
A score of how well the liver works in people with liver disease such as cirrhosis: class A is mild, B moderate and C severe.
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.
Arumakimig from Day 1 to Week 52 during the double-blind period. Eligible participants may then continue into an open-label extension and receive arumakimig through Week 156.
Drug: Arumakimig · Drug: Oral glucocorticoids
Placebo from Day 1 to Week 52 during the double-blind period. Eligible participants may then continue into an open-label extension and receive arumakimig through Week 156.
Drug: Arumakimig · Drug: Placebo · Drug: Oral glucocorticoids
Arumakimig Injection
Also known as: MAS825
Placebo Injection
Background therapy with glucocorticoids. After the first 2 weeks of the study, participants may begin with glucocorticoid tapering depending on the disease status and the Investigator's judgement.
Number of participants achieving improvement of key VEXAS manifestations and oral glucocorticoid (GC) reduction at Week 52
Response is defined as meeting both criteria: A) Clinical domain: In participants with clinical disease activity in any domain at baseline, complete resolution of clinical manifestations related to active disease in at least one affected domain. In participants with no clinical disease activity in any domain at baseline, continued absence of clinical manifestations in all domains at Week 52. AND B) Protocol-defined glucocorticoid reduction through 52 weeks.
Time frame: From baseline up to Week 52
Number of participants achieving Overall Clinical Response (OCR) at Week 52
Achieving OCR at Week 52 is defined as meeting all the following criteria: * Absence of active inflammatory manifestations of VEXAS * Protocol-defined reduction in oral glucocorticoid. * Protocol-defined reduction in C reactive protein.
Time frame: From baseline up to Week 52
Number of participants achieving resolution of VEXAS manifestations
In participants with clinical disease activity in any domain at baseline, achieving complete resolution of clinical manifestations.
Time frame: From baseline up to Week 52
Number of participants with oral glucocorticoid reduction
Number of participants achieving protocol-defined glucocorticoid dose reduction through 52 weeks.
Time frame: From baseline up to Week 52
Total number of flare-free days over 52 weeks
Total cumulative number of days over 52 weeks meeting the protocol-defined criteria for a flare-free day.
Time frame: Up to 52 weeks
Number of participants achieving Hematologic Improvement - Erythroid (HI-E) during the double-blind treatment period
Hematologic Improvement - Erythroid (HI-E) during the double-blind 52-week treatment period among participants with baseline hemoglobin within the protocol-defined range, according to modified International Working Group (IWG) and protocol-defined response criteria.
Time frame: From baseline up to Week 52
Number of participants achieving Hematologic Improvement - Platelets (HI-P) during the double-blind treatment period
Hematologic Improvement - Platelets (HI-P) during the double-blind 52-week treatment period among participants with baseline platelets within the protocol-defined range, according to modified International Working Group (IWG) and protocol-defined response criteria.
Time frame: From baseline up to Week 52
Number of participants without worsening disease according to a participant-reported questionnaire
Participants without protocol-defined worsening of disease according to a participant-reported questionnaire.
Time frame: From baseline up to Week 52
Time to death during the double-blind treatment period
Assessment of mortality through Week 52 in each treatment arm.
Time frame: Up to 52 weeks
Number of participants with adverse events (AEs) and serious adverse events (SAEs)
Number of participants with AEs and SAEs, including changes in vital signs, electrocardiograms and laboratory values qualifying and reported as AEs.
Time frame: Up to 172 weeks
Plan to share: Yes — Novartis is committed to sharing with qualified external researchers, access to patient-level data and supporting clinical documents from eligible studies. These requests are reviewed and approved by an independent review panel on the basis of scientific merit. All data provided is anonymized to respect the privacy of patients who have participated in the trial in line with applicable laws and regulations. This trial data availability is according to the criteria and process described on https://www.clinicalstudydatarequest.com/.
No publications or documents are linked to this record.
Start is estimated for Oct 2026; primary completion for Dec 2028, 25 months later.
Of 29 phase 2 interventional studies under Arthritis, half reached primary completion within 19 months of starting (the median), counting those still running; a quarter within 15 and three quarters within 36. This study's planned 25 months is above that.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Studies of the drug tested here: Arumakimig