Primary Angiitis of the Central Nervous System (PACNS) in RemissionPhase 2MAINRIPACNCT07902492
Efficacy of Rituximab for Remission Maintenance in Patients With Primary Angiitis of the Central Nervous System: an Open-label, Randomized, Controlled Trial Comparing Systematic Rituximab Infusions and Azathioprine
A Phase 2 study testing RUXIENCE®., Brain MRI and Azathioprine 50 MG in people with Primary Angiitis of the Central Nervous System (PACNS) in Remission, run by Centre Hospitalier St Anne.
Trial summary
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). Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Primary Angiitis of the Central Nervous System (PACNS) in Remission
- What is being tested?
- RUXIENCE®., Brain MRI and Azathioprine 50 MG
- Type of treatment
- Pill or oral medicine, Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 74 participants
- Where
- No sites listed yet
- Study dates
- 1 Jan 2027to 1 Jan 2032
- Phase
- Phase 2
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Patient aged 18 years or older
- Patients who have documented PACNS diagnosis
- Diagnosis is made if the following criteria are met:
- History or clinical findings of an acquired neurological deficit of unknown origin after a thorough initial basic assessment; Cerebral angiogram with classic features of vasculitis (alternating areas of smooth-wall segmental narrowing and dilatation of cerebral arteries, arterial occlusions affecting many cerebral vessels, absence of proximal vessel atherosclerosis or other recognized abnormalities), and/or abnormal findings on MRI and CSF profile consistent with PACNS;
- Or CNS biopsy sample showing vasculitis;
- And no evidence of systemic vasculitis or any other disorder to which the angiographic or pathological features could be secondary (e.g. atherosclerosis, reversible cerebral vasoconstriction syndrome…)
Show all 11Show fewer
- Diagnosis of PACNS validated by the study committee
- Patients in remission after induction therapy
- Use of an effective method of contraception for female participants of childbearing age. Women of childbearing potential is defined as any female who has experienced menarche and who has not undergone surgical sterilization (hysterectomy or bilateral oophorectomy) or is not postmenopausal. Menopause is defined clinically as 12 months of amenorrhea in a woman over age 45 in the absence of other biological or physiological causes.
- Patient able to give written informed consent prior to participation in the study
- Affiliation with a mode of social security
Who cannot join
- Patients with other vasculitis
- Patients with severe cardiac failure
- Patients with acute or chronic active infections
- Patients with active or recent cancer (< 5 years)
- Pregnant women and lactation
- Patients with hypersensitivity to a monoclonal antibody or biologic agent
Show all 9Show fewer
- Patients suspected not to be observant to the proposed treatments
- Patients unable to give written informed consent prior to participation in the study
- Patients under guardianship, conservatorship, or subject to a court-ordered restraint Administration récente d'un vaccin vivant atténué incompatible avec l'instauration du traitement de l'étude,
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
About this study
Official title: Efficacy of Rituximab for Remission Maintenance in Patients With Primary Angiitis of the Central Nervous System: an Open-label, Randomized, Controlled Trial Comparing Systematic Rituximab Infusions and Azathioprine"
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.
Read the detailed description
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.
- Being tested
- RUXIENCE®., Brain MRI, Azathioprine 50 MG
- Medical subject headings
- Primary angiitis of the central nervous system
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
RUXIENCE®.Drug
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 MRIOther
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.
Azathioprine 50 MGDrug
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.
| Study group | Role | What they receive |
|---|---|---|
| Rituximab | Experimental | Participants receive rituximab 1,000 mg intravenously at Day 0, Day 14, Month 6, Month 12, and Month 18. Receives: Drug: RUXIENCE®.; Other: Brain MRI |
| Azathioprine | Active comparator | 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. Receives: Other: Brain MRI; Drug: Azathioprine 50 MG |
What is being measured
The primary outcome is the main question the study is designed to answer.
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.
Measured: 24 month
Secondary outcomes (13)
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.
Measured: 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.
Measured: 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.
Measured: 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.
Measured: 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.
Measured: 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.
Measured: 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.
Measured: 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.
Measured: 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.
Measured: 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.
Measured: 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.
Measured: 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.
Measured: 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.
Measured: From randomization to Month 24
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted29 Oct 2026
- Study start1 Jan 2027 (estimated)
- Primary completion1 Jan 2030 (estimated)
- Study completion1 Jan 2032 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Primary Angiitis of the Central Nervous System (PACNS) in RemissionStudies of the same condition, open and under way.
- More trials run by Centre Hospitalier St AnneThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- For MAINRIPAC, participants are randomized 1:1 into two parallel treatment groups: * Rituximab * Azathioprine
- Masking
- None (open label)
- Enrolment
- 74 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Centre Hospitalier St Anne
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Nicolas MÉLÉ, Study chair, Department of Neurology
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07902492
- Sponsor's protocol ID
- D25 - P043
- Acronym
- MAINRIPAC
- Status last verified
- Sep 2026
- First submitted
- 22 Oct 2026
- Last updated
- 29 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: The data will be used exclusively for the analyses planned in the protocol and will not be shared outside the study investigators.
Study at a glance
From the registry record, last updated by the sponsor on 29 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Efficacy of Rituximab for Remission Maintenance in Patients With Primary Angiitis of the Central Nervous System: an Open-label, Randomized, Controlled Trial Comparing Systematic Rituximab Infusions and Azathioprine"
- ClinicalTrials.gov ID
- NCT07902492
- Acronym / sponsor ID
- MAINRIPAC / D25 - P043
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 74 participants (estimated)
- Lead sponsor
- Centre Hospitalier St AnneUniversity, hospital or other
- Study start
- 1 Jan 2027 (estimated)
- Primary completion
- 1 Jan 2030 (estimated)
- Study completion
- 1 Jan 2032 (estimated)
- First posted
- 29 Oct 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Detailed description
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.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- For MAINRIPAC, participants are randomized 1:1 into two parallel treatment groups: * Rituximab * Azathioprine
| Arm | Type | Receives |
|---|---|---|
| Rituximab | Experimental | Drug: RUXIENCE®., Other: Brain MRIParticipants receive rituximab 1,000 mg intravenously at Day 0, Day 14, Month 6, Month 12, and Month 18. |
| Azathioprine | Active comparator | Other: Brain MRI, Drug: Azathioprine 50 MGParticipants 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. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (11 listed)
- Patient aged 18 years or older
- Patients who have documented PACNS diagnosis
- Diagnosis is made if the following criteria are met:
- Diagnosis of PACNS validated by the study committee
- Patients in remission after induction therapy
Key exclusion criteria (9 listed)
- Patients with other vasculitis
- Patients with severe cardiac failure
- Patients with acute or chronic active infections
- Patients with active or recent cancer (< 5 years)
- Pregnant women and lactation
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| RUXIENCE®.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. | Drug | Rituximab |
| Brain MRIBrain 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. | Other | Azathioprine, Rituximab |
| Azathioprine 50 MGParticipants 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. | Drug | Azathioprine |
Primary outcome
To determine the superiority of rituximab over azathioprine for maintenance therapy in patients with primary angiitis of central nervous system
Time frame: 24 month
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.
13 secondary outcomes
Proportion of participants without relapse at 12 and 24 months
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)
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
Time frame: Month 12 and Month 24
Proportion of participants without evidence of new stroke lesion at 12 and 24 months
Time frame: Month 12 and Month 24
Proportion of participants without evidence of new contrast-enhanced lesions at 12 and 24 months
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.
Time frame: Month 12 and Month 24
Proportion of participants without evidence of progression ≥ 50% of preexisting intracranial stenosis at 12 and 24 months.
Time frame: Month 12 and Month 24
Proportion of participants necessitating treatment change or escalation at 12 and 24 months
Time frame: Month 12 and Month 24
Proportion of participants with favorable outcome defined as mRS < 3 at 12 and 24 months
Time frame: Month 12 and Month 24
SF-36 at 12 and 24 months
Time frame: Month 12 and Month 24
Prednisone dosage at 12 and 24 months
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
Time frame: From randomization to Month 12 and Month 24
Proportion of death
Time frame: From randomization to Month 24
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 Oct 2026.
- Individual participant dataSharing planned: No. The data will be used exclusively for the analyses planned in the protocol and will not be shared outside the study investigators.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Nicolas MÉLÉ study chair
Department of Neurology
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing RUXIENCE®., Brain MRI and Azathioprine 50 MG in people with Primary Angiitis of the Central Nervous System (PACNS) in Remission, run by Centre Hospitalier St Anne.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 11 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 29 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Naoual khalfi, projetc manager (01.45.65.73.85 ext. +33, n.khalfi@ghu-paris.fr), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
To determine the superiority of rituximab over azathioprine for maintenance therapy in patients with primary angiitis of central nervous system (time frame: 24 month). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Oct 2026.