A Phase 2 interventional study of MAS825 and Placebo in NLRC4-GOF, AIFEC (Autoinflammation With Infantile Enterocolitis), XIAP Deficiency, CDC42 Mutations, sponsored by Novartis Pharmaceuticals. Active, not recruiting at 12 sites in 7 countries. Open to participants aged 0 Years and older. Per ClinicalTrials.gov, last updated 2026-10-09.
Sponsored by Novartis Pharmaceuticals (part of Novartis) · Phase 2, Interventional, and Treatment
This study is a Phase 2 trial designed to evaluate the clinical efficacy, safety, and tolerability of MAS825 in patients with NLRC4-GOF, XIAP deficiency, or CDC42 mutations.
This is a three-period study, with an open-label, single-arm active treatment in Period 1 followed by a randomized-withdrawal, double-blinded, placebo-controlled design in Period 2, and an open label, long-term safety follow-up in Period 3, Period 3s, \& Period 3s open label extension.
The total study duration is up to approximately 11 years.
Patients who enter Period 2 will be randomized to MAS825 or matching placebo in a 1:1 ratio.
Cohort 1 patients will complete all periods of the study.
Cohort 2: Patients who are receiving MAS825 in a Novartis Managed Access Program with a diagnosis of NLRC4-GOF, XIAP deficiency, or CDC42 mutation who meet criteria will be eligible to directly enter into Period 3 open-label long-term safety follow-up. They can continue into Period 3s, and Period 3s open-label extension.
21 studies on the registry are indexed under Enterocolitis; 3 are open to participants now.
This study's enrollment of 17 is below the median of 75 across 14 interventional studies indexed under Enterocolitis.
Browse Enterocolitis 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.
For all Patients:
Written by parent(s)/legal guardian(s) for the pediatric patients and assent by the pediatric patient (depending on local requirements) must be obtained before any study-specific assessment is performed. For adult patients, written informed consent by patients capable of giving consent, or when the patient is not capable of giving consent, by his/her legal/authorized representative (if allowed according to local requirements).
Cohort 1 specific inclusion criteria:
At first treatment, evidence of active disease as assessed by inflammatory markers and PGA
Cohort 2 specific inclusion criteria:
Exclusion Criteria:
Signs and symptoms, in the judgment of the investigator, of active bacterial, fungal, parasitic or viral infections, excluding chronic Epstein-Barr Virus (EBV).
- COVID-19 specific: If in line with health and governmental authority guidance, it is highly recommended that testing to exclude COVID-19 using PCR or comparable approved methodology be completed within 1 week prior to first dosing.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Experimental drug
Biological: MAS825
matching placebo
Biological: Placebo
Experimental drug
matching placebo
Cohort 1: Occurrence of disease flare in patients with MAS825 treated patients compared with placebo during Period 2 assessed by Physician's Global Assessment and inflammatory markers
To determine the efficacy of MAS825 in prevention of flares in patients with monogenic IL-18 driven autoinflammatory diseases, including NLRC4-GOF, XIAP deficiency or CDC42 mutations
Time frame: Period 2 (during the randomized, placebo-controlled period of up to 6 months)
All cohorts: Number and severity of safety assessments and adverse events
To evaluate the safety and tolerability of MAS825
Time frame: Screening through EOS (End of Study) (up to approximately 11 years)
All cohorts: Confirmation of serological markers of MAS825
Evaluate the serological markers of MAS825
Time frame: Day 1 through EOS (up to approximately 11 years)
Cohort 1: PGA and inflammatory markers
Evaluate the efficacy of MAS825 to improve the clinical status of patients with NLRC4-GOF, XIAP deficiency or CDC42 mutations
Time frame: Day 29, end of Period 1 (approximately 6 months), end of Period 2 (year 1), end of Period 3 (year 4), and end of Period 3s (up to year 6)
Cohort 1: Serological remission via inflammatory markers
Evaluate efficacy of MAS825 to achieve serological remission
Time frame: Day 29, end of Period 1 (up to 6 months), and end of Period 2 (year 1), end of Period 3 (year 4), and end of Period 3s (up to year 6)
Cohort 1: Glucocorticoid therapy <0.2mg/kg by end of period 1
Evaluate the effect of MAS825 on concomitant glucocorticoid administration
Time frame: End of Period 1 (approximately 6 months)
Cohort 1: Time to first flare
Evaluate effect of MAS825 on the time to first flare
Time frame: Period 2 (during the randomized, placebo-controlled period of up to 6 months)
All cohorts: Physician Severity Assessment of Disease Signs and Symptoms scale (PSADSS)
Evaluate the efficacy of MAS825 to improve signs and symptoms of the disease
Time frame: Screening through EOS (up to approximately 11 years)
All cohorts: Patient / Parent global assessment of disease activity (PPGA) scale
Evaluate effect of MAS825 on patient reported outcomes over time
Time frame: Screening through EOS (up to approximately 11 years)
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 www.clinicalstudydatarequest.com
No publications or documents are linked to this record.
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 ↗
This study is active, not recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Arumakimig