Rituximab vs Placebo for Maintenance in Systemic Sclerosis - Interstitial Lung Disease (MAINRITSyS)

The purpose of this study is to determine whether Rituximab is safe and effective as a maintenance strategy in individuals with stabilized systemic sclerosis in adults.

Study Overview

• Status: Not yet recruiting
• Conditions: Systemic Sclerosis in Adults
• Intervention / Treatment: Drug: Rituximab; Drug: Placebo

Detailed Description

Systemic sclerosis (SSc) is a rare autoimmune connective tissue-disease. Interstitial lung disease (ILD) is a common manifestation and a leading cause of death in SSc.

Rituximab (RTX) is commonly used in SSc-ILD induction treatment and recent trials have now fully demonstrated its safety and efficacy as an induction treatment. The DESIRES trial reported that RTX-induction was associated with a 24-week stabilization of FVC. As evaluated by the FVC at 24 weeks from baseline, 25 patients with SSc-ILD treated with RTX were significantly improved compared with 23 patients treated with placebo (0.09% vs -2.87%; [95%CI 0.08-5.84]; p < 0.05). Recently, the RECITAL trial showed the absence of difference between induction treatment with cyclophosphamide (CYC) and RTX in ILD including SSc-ILD. Indeed, both RTX and CYC resulted in an improvement in FVC (97 ± 234mL and 99 ± 329mL respectively) at 24 weeks, without significant statistical difference in 101 subjects. Furthermore, the EVER-ILD study, also very recently presented, reported a beneficial of RTX in addition to mycophenolate mofetil (MMF) over RTX in CTD-ILD. Altogether with previous European database studies which analyzed the very common usage of RTX as induction therapy in SSc, these studies have confirmed its efficient and safe role as an induction treatment in SSc-ILD.

Still, the impact of re-treatment with RTX in maintaining ILD-stabilization has never been studied and deserve to be studied.

The hypothesis that drives the MAINRITSyS is that RTX maintains ILD stabilization in SSc-ILD.

• Study Type: Interventional
• Enrollment (Estimated): 120
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Benjamin CHAIGNE, MD; Phone Number: +33 01 58 41 41 17; Email: benjamin.chaigne@aphp.fr
• Study Contact Backup: Name: Adèle BELLINO, PHD; Phone Number: +33 01 71 76 07 57; Email: adele.bellino@aphp.fr

Study Locations

• France
  • Île-de-France Region
    • Paris, Île-de-France Region, France, 75014
      • Cochin Hospital
      • Contact: Benjamin CHAIGNE, MD; Phone Number: +33 01 58 41 41 17; Email: benjamin.chaigne@aphp.fr

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adult patient (≥ 18 years old),
• Patient with a diagnosis of SSc, as defined by the ACR/EULAR 2013 criteria (cf. Table 2) (6)
• Patient with ILD identified on the basis of a HRCT, obtained within 12 months before screening, that showed fibrosis affecting at least 10% of the lungs,
• SSc-ILD induction with RTX, either twice 1000 mg two weeks apart, or 375 mg/m2 four times 4 weeks apart.

The interval between the last induction dose and the first maintenance dose should be 6 months +/- 15 days.

• Patient with stabilized SSc-ILD following RTX induction treatment as defined by the absence of worsening respiratory symptoms, an absolute decline of FVC of < 5% of the predicted value, an absence of absolute decline of DLCO (corrected for hemoglobin) of < 10% related to SSc-ILD, and absence of radiological evidence of disease progression on HRCT(97)
• All required vaccinations must have been carried out at least 4 weeks before D0. According to recommendations, prophylaxis against pneumocystis is recommended for scleroderma, but not mandatory.
• Woman of childbearing potential should have reliable contraception* for the 12 months' duration of the study's treatment and 12 months after last administration,
• Patient able to give written informed consent prior to participation in the study,
• Affiliation to a social security scheme (profit or being entitled). AME is not accepted.

Exclusion Criteria

• Forced vital capacity < 40% of the predicted value
• Diffusion capacity of the lung for carbon monoxide (DLCO) (corrected for hemoglobin) < 30% of the predicted value.
• Contra-indication or anaphylaxis toward RTX
• Contra-indication to auxiliary medicinal products
• Cyclophosphamide, tacrolimus, ciclosporin, or voclosporin during the 2 months prior to screening or during screening
• Any biologic therapy (including other anti-CD20, anti-CD19, or anti-plasma cell) such as, but not limited to, belimumab, ustekinumab, anifrolumab, secukinumab, or atacicept during the 2 months prior to screening or during screening
• Inhibitors of Janus-associated kinase (JAK), Bruton's tyrosine kinase (BTK), or tyrosine kinase 2 (TYK2), including baricitinib, tofacitinib, upadacitinib, filgotinib, ibrutinib, or fenebrutinib or any investigational agent during the 2 months prior to screening or during screening
• Any live vaccine during the 28 days prior to screening or during screening
• High risk for clinically significant bleeding or any condition requiring plasmapheresis, IV immunoglobulin, or acute blood product transfusions during the 28 days prior the screening
• Active infection with SARS-CoV-2 or absence of COVID-19 vaccination within the last six months (this criteria will be updated at the time of submission to European Agency to be in adequation with national recommendation at the time of submission).
• Significant or uncontrolled medical disease which, in the investigator's opinion, would preclude patient participation
• HIV infection : for participants with unknown HIV status (if the previous tests date more than 3 months), HIV testing will be performed locally at screening.
• Tuberculosis (TB) infection: Testing for latent TB will be performed locally at screening if required by local regulations or in accordance with local clinical practice. Latent TB after completion of appropriate treatment is not exclusionary
• Active infection of any kind, excluding fungal infection of the nail beds.
• History of serious recurrent or chronic infection
• History of progressive multifocal leukoencephalopathy (PML)
• History of cancer, including solid tumors, hematological malignancies, and carcinoma in situ, within the past 5 years. Participants with non-melanomatous carcinomas of the skin that have been treated or excised and have resolved are eligible.
• Major surgery requiring hospitalization during the 4 weeks prior to screening or during screening
• Current alcohol or drug abuse or history of alcohol or drug abuse within 12 months prior to screening or during screening
• History of severe allergic or anaphylactic reactions to monoclonal antibodies or known hypersensitivity to any component of the RTX infusion

• Any of the following laboratory parameters:

  • AST or ALT above 2.5 upper limit normal range
  • Neutrophils <1.5x103/mL
  • Positive hepatitis B surface antigen (HBsAg)
  • Positive hepatitis C serology Participants with positive hepatitis C antibody test result with no detectable hepatitis C virus (HCV) RNA for at least 6 months after completion of antiviral therapy are eligible but will require monthly HCV RNA monitoring until 12 months after the last dose of RTX or placebo.
• Pregnancy or breastfeeding
• Participation in another interventional study or being in the exclusion period at the end of a previous study.
• Participants under court supervision, guardianship, or conservatorship.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Rituximab; 500mg of i.v rituximab at M0, M6 and M12	Drug: Rituximab; 500mg i.v at M0, M6 and M12
Placebo Comparator: Placebo; 500mg of i.v placebo at M0, M6 and M12	Drug: Placebo; 500mg i.v at M0, M6 and M12

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
changes in forced vital capacity (FVC) from baseline to Month 18 of randomisation.	PFTs: changes in forced vital capacity (FVC)	18 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mortality up to 18 months		18 months
Occurrence of Adverse Events	Occurrence of adverse events, overall and occurring at time of perfusion (day 0, and 6, 12 and 18 months)	At 6, 12 and 18 months
Occurrence of Adverse Events	The number of adverse events, expressed according to the Common Terminology Criteria for Adverse Events (CTCAE): CTCAE toxicity grading system per patient-year at month 6, 12, and 18, for the following adverse events combined: death (all causes), grade 2 or higher leukopenia or thrombocytopenia, grade 3 or higher infections, hospitalization resulting either from the disease or from a complication due to the study treatment.	At 6, 12 and 18 months
Occurrence of AE of specific interest previously mentioned at 6, 12 and 18 months		At 6, 12 and 18 months
Change in gammaglobulin, lymphocytes and CD19 levels at 6, 12 and 18 months		At 6, 12 and 18 months
Change from baseline in DLCO over 6, 12, and 18 months		At 6, 12 and 18 months
Change from baseline in TLC over 6, 12, and 18 months		At 6, 12 and 18 months
Further analyses on TLC	Absolute categorical change of % TLC at 6, 12 and 18 months (decrease by >5%, increase by >5% and change within <5%) Absolute categorical change of % TLC at 6, 12 and 18 months (decrease by >10%, increase by >10% and change within <10%)	At 6, 12 and 18 months
Change from in 6-min walk test distance over 6, 12 and 18 months		At 6, 12 and 18 months
Further analyses on FVC	Absolute categorical change of % FVC at 6, 12 and 18 months (decrease by >5%, increase by >5% and change within <5%); Absolute categorical change of % FVC at 6, 12 and 18 months (decrease by >10%, increase by >10% and change within <10%)	At 6, 12 and 18 months
Progression-free survival (composite endpoint of mortality, transplant, treatment failure or decline in FVC >10% compared to baseline) over 6, 12 and 18 months		At 6, 12 and 18 months
Treatment failure (as determined by need for transplant or rescue therapy) at 6, 12 and 18 months		At 6, 12 and 18 months
INBUILD progression (as determined by the INBUILD criteria for ILD progression(73)) at 6, 12 and 18 months		At 6, 12 and 18 months
Change from baseline in capillary oxygen saturation (SpO2) at 6, 12 and 18 months		At 6, 12 and 18 months
Changes from baseline to 18 months in HRCT of chest images		At 18 months
Proportions of patients who achieved 20%, 30%, 40%, 50% ,60%, 70%, 80%, 90% and 100% response criteria according to revised CRISS at 6, 12 and 18 months		At 6, 12 and 18 months
Changes in physicians visual analogue scales over 18 months.	These scales range from 0 (minimum) to ten (maximum) points and will be performed at day 0, at 6, 12, and 18 months. Higher score mean worse outcome	at 0, 6, 12, 18 months
Changes in patients' visual analogue scales over 18 months.	These scales range from 0 (minimum) to ten (maximum) points and will be performed at day 0, at 6, 12, and 18 months. Higher score mean better outcome	At 0, 6, 12, and 18 months
Changes in mRSS at 6, 12, and 18 months	Higher score mean worse outcome.	At 6, 12 and 18 months
Proportion of patients who improved mRSS at 6, 12 and 18 months after randomisation.		At 6, 12 and 18 months
Proportion of patients with an active disease according to the European scleroderma trials and research group (EUSTAR) SSc activity index at 6, 12 and 18 months after randomisation		At 6, 12 and 18 months
Saint Georges Respiratory Hospital Questionnaire at day 0, and at 6, 12, and 18 months after randomisation.	These questionnaires are self-administered questionnaires assessing the perception of lung disease by the patients. These scales range from 0 (minimum) to one hundred (maximum) points. Higher score mean worse outcome	At 0, 6, 12 and 18 months
King Brief's Interstitial Lung Disease questionnaire at day 0, and at 6, 12, and 18 months after randomisation.	These questionnaires are self-administered questionnaires assessing the perception of lung disease by the patients. These scales range from 0 (minimum) to 100 (maximum) points. Higher score mean better outcome	at 0, 6, 12, and 18 months
Short Form-36 (SF-36) health questionnaire	SF36 : 0 à 100 - These scales range from 0 (minimum) to 100 (maximum) points. Higher score mean better outcome - to assess Quality of life	At 0, 6, 12 and 18 months
EuroQol-5 Domain (EQ5D5L) health questionnaire	EQ5D5L : The EQ-5D-5L instrument comprises five dimensions: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Each dimension is rated on a five-point scale, from 1 (no problems) to 5 (extreme problems), with higher scores reflecting worse health status. To assess quality of life.	At 0, 6, 12 and 18 months
Scleroderma skin patients reported outcome (SSPRO) at day 0, and at 6, 12 and 18 months after randomisation.		At 0, 6, 12 and 18 months
HAQ-DI and SHAQ scales at day 0, and at 6, 12 and 18 months after randomisation. These scales range from 0 (minimum) to 3 (maximum) points. Higher score mean worse outcome		At 0, 6, 12 and 18 months
Total corticosteroid requirement at 6, 12 and 18 months		At 6, 12 and 18 months
Levels of prespecified biomarkers (KL-6, SP-D, MUC1, SFTPD, CCL18 and CXCL4) at months 6, 12 and 18 months.		At 6, 12 and 18 months
Presence of anti-RTX-antibody at months 6, 12 and 18.		At 6, 12 and 18 months
Dosage of plasma and serum residual concentration of RTX at months 6, 12 and 18		At 6, 12 and 18 months
Hospitalisation for respiratory cause over the duration of the trial		At 18 months
Time to first hospitalisation for respiratory cause		At 18 months
Time to death		At 18 months
Time to first acute ILD exacerbation		At 18 months

Collaborators and Investigators

• Sponsor: Assistance Publique - Hôpitaux de Paris
• Collaborators: URC-CIC Paris Descartes Necker Cochin
• Investigators: Study Chair: Luc MOUTHON, MD, PhD, AP-HP - Hôpital Cochin 27 Rue du Faubourg Saint Jacques 75014 France

Study record dates

Study Major Dates

• Study Start (Estimated): October 1, 2026
• Primary Completion (Estimated): May 1, 2030
• Study Completion (Estimated): March 1, 2031

Study Registration Dates

• First Submitted: July 9, 2026
• First Submitted That Met QC Criteria: September 14, 2026
• First Posted (Actual): September 18, 2026

Study Record Updates

• Last Update Posted (Actual): September 18, 2026
• Last Update Submitted That Met QC Criteria: September 14, 2026
• Last Verified: September 1, 2026

More Information

Terms related to this study

• Keywords: Rituximab; Systemic sclerosis
• Additional Relevant MeSH Terms: Connective Tissue Diseases; Skin Diseases; Skin and Connective Tissue Diseases; Scleroderma, Systemic; Amino Acids, Peptides, and Proteins; Proteins; Antibodies, Monoclonal; Antibodies; Immunoglobulins; Immunoproteins; Blood Proteins; Serum Globulins; Globulins; Antibodies, Monoclonal, Murine-Derived; Rituximab
• Other Study ID Numbers: APHP240909; 2025 (U.S. NIH Grant/Contract: Faculty of Social Sciences Scientific Grant at the University of Gdańsk); 2025-521331-36-00 (Ctis)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No