A Phase 2 interventional study of RUXIENCE®. and Brain MRI in Primary Angiitis of the Central Nervous System (PACNS) in Remission, sponsored by Centre Hospitalier St Anne. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-29.
Sponsored by Centre Hospitalier St Anne · Phase 2, Interventional, and Treatment
MAINRIPAC is a multicenter, randomized, open-label controlled clinical trial evaluating the efficacy of rituximab versus azathioprine for maintenance of remission in patients with primary angiitis of the central nervous system (PACNS). Patients are randomized 1:1 to receive either rituximab or azathioprine and are followed for 24 months, with regular clinical and brain MRI assessments to evaluate disease relapse and treatment safety.
MAINRIPAC is a multicenter, randomized, open-label, controlled clinical trial designed to evaluate the efficacy and safety of rituximab compared with azathioprine for maintenance of remission in patients with primary angiitis of the central nervous system (PACNS).
Eligible patients with PACNS in remission are randomized in a 1:1 ratio to one of two treatment groups.
Patients allocated to the rituximab group receive intravenous rituximab 1,000 mg on Day 0 and Day 14, followed by additional administrations at Months 6, 12 and 18.
Patients allocated to the azathioprine group receive oral azathioprine according to a progressive dose-reduction schedule: 2 mg/kg/day for the first 12 months, 1.5 mg/kg/day for the following 6 months, and 1 mg/kg/day for the final 4 months, for a total treatment duration of 22 months.
Each participant is followed for 24 months. Clinical assessments and brain magnetic resonance imaging (MRI) are performed at baseline and at Months 6, 12, 18 and 24. Additional MRI examinations may be performed according to the patient's clinical course, particularly in the event of suspected relapse.
Brain MRI examinations are centralized and reviewed in a blinded manner. In the event of suspected disease relapse, the relevant clinical and imaging data are reviewed according to a predefined adjudication process involving independent experts.
The main objective of the study is to determine whether rituximab is effective for maintaining remission and preventing relapse compared with azathioprine. Secondary objectives include the assessment of treatment safety, clinical outcomes and radiological disease activity during the 24-month follow-up period.
The study is conducted in multiple participating centers in France under the sponsorship of GHU Paris Psychiatrie \& Neurosciences.
Centre Hospitalier St Anne is the lead sponsor of 101 studies on the registry; 55 are open to participants now.
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.
Diagnosis is made if the following criteria are met:
Exclusion Criteria:
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.
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.
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.
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
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.
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.
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.
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.
Postmenopausal
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
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.
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.
Participants receive rituximab 1,000 mg intravenously at Day 0, Day 14, Month 6, Month 12, and Month 18.
Drug: RUXIENCE®. · Other: Brain MRI
Participants receive oral azathioprine: * 2 mg/kg/day for 12 months * 1.5 mg/kg/day for 6 months * 1 mg/kg/day for 4 months Total azathioprine treatment duration: 22 months.
Other: Brain MRI · Drug: Azathioprine 50 MG
Participants assigned to the rituximab arm receive rituximab 1,000 mg by intravenous infusion on Day 0 and Day 14, followed by maintenance administrations at Month 6, Month 12, and Month 18. Treatment is administered according to the protocol and local standard procedures, with appropriate premedication and clinical monitoring before, during, and after each infusion.
Brain magnetic resonance imaging (MRI) is performed at baseline and at Months 6, 12, 18, and 24. Additional brain MRI examinations may be performed according to the patient's clinical course, particularly in the event of suspected relapse. MRI examinations are centralized for blinded review according to the study procedures.
Participants receive oral azathioprine: * 2 mg/kg/day for 12 months * 1.5 mg/kg/day for 6 months * 1 mg/kg/day for 4 months Total azathioprine treatment duration: 22 months.
To determine the superiority of rituximab over azathioprine for maintenance therapy in patients with primary angiitis of central nervous system
To compare the efficacy of rituximab versus azathioprine in maintaining remission in patients with primary angiitis of the central nervous system (PACNS), based on the occurrence of clinical and/or radiological relapse during follow-up. Relapse is assessed using clinical evaluation and brain MRI findings according to the study protocol.
Time frame: 24 month
Proportion of participants without relapse at 12 and 24 months
Proportion of participants who remain free from PACNS relapse at 12 and 24 months after randomization. Relapse is defined according to the clinical and/or radiological criteria specified in Section 4.1.1 of the protocol.
Time frame: Month 12 and Month 24
Proportion of participants without "clinical relapse" (i.e. new neurological symptoms attributable to active PACNS) at 12 and 24 months (see definition in section 4.1.1 of the protocol)
Proportion of participants without clinical relapse at 12 and 24 months. Clinical relapse is defined as the occurrence of new neurological symptoms attributable to active primary angiitis of the central nervous system (PACNS), according to the definition provided in Section 4.1.1 of the protocol.
Time frame: Month 12 and Month 24
Proportion of participants without "radiological relapse" (i.e. worsening of existing or evidence of new abnormal neuroimaging findings on MRI consistent with PACNS activity) at 12 and 24 months
Proportion of participants without radiological relapse at 12 and 24 months. Radiological relapse is defined as worsening of pre-existing neuroimaging abnormalities or the occurrence of new MRI abnormalities consistent with active primary angiitis of the central nervous system (PACNS), according to the definition provided in Section 4.1.1 of the protocol.
Time frame: Month 12 and Month 24
Proportion of participants without evidence of new stroke lesion at 12 and 24 months
Proportion of participants with no evidence of new stroke lesions on brain MRI at 12 and 24 months compared with baseline imaging.
Time frame: Month 12 and Month 24
Proportion of participants without evidence of new contrast-enhanced lesions at 12 and 24 months
Proportion of participants with no evidence of new contrast-enhancing lesions on brain MRI at 12 and 24 months compared with baseline imaging.
Time frame: Month 12 and Month 24
Proportion of participants without evidence of new intracranial stenosis on proximal cerebral arteries at 12 and 24 months.
Proportion of participants with no evidence of new intracranial stenosis involving the proximal cerebral arteries on brain vascular imaging at 12 and 24 months compared with baseline imaging.
Time frame: Month 12 and Month 24
Proportion of participants without evidence of progression ≥ 50% of preexisting intracranial stenosis at 12 and 24 months.
Proportion of participants with no evidence of progression of pre-existing intracranial stenosis by 50% or more on brain vascular imaging at 12 and 24 months compared with baseline.
Time frame: Month 12 and Month 24
Proportion of participants necessitating treatment change or escalation at 12 and 24 months
Proportion of participants requiring a change or escalation of maintenance therapy due to suspected or confirmed PACNS disease activity during follow-up, including treatment modification, intensification, or initiation of additional immunosuppressive therapy.
Time frame: Month 12 and Month 24
Proportion of participants with favorable outcome defined as mRS < 3 at 12 and 24 months
Proportion of participants achieving a favorable functional outcome, defined as a modified Rankin Scale (mRS) score of less than 3, at 12 and 24 months.
Time frame: Month 12 and Month 24
SF-36 at 12 and 24 months
Health-related quality of life assessed using the 36-Item Short Form Health Survey (SF-36) at 12 and 24 months.
Time frame: Month 12 and Month 24
Prednisone dosage at 12 and 24 months
Daily prednisone dose, expressed in mg/day, at 12 and 24 months to assess corticosteroid exposure during maintenance therapy.
Time frame: Month 12 and Month 24
The number of adverse events according to the Common Terminology Criteria for Adverse Events (CTCAE) toxicity grading system at 12 and 24 months
Number of adverse events occurring during the study, classified according to the Common Terminology Criteria for Adverse Events (CTCAE) toxicity grading system.
Time frame: From randomization to Month 12 and Month 24
Proportion of death
Proportion of participants who die from any cause during the study follow-up period.
Time frame: From randomization to Month 24
No study locations are listed for this record.
Plan to share: No — The data will be used exclusively for the analyses planned in the protocol and will not be shared outside the study investigators.
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 not yet recruiting, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
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