Long-term Safety and Efficacy Study of Riliprubart in Participants With CIDP (LTS)

Long-term Extension Study to Evaluate the Safety and Efficacy of Riliprubart (SAR445088) in Participants With Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)

This study is a Phase 3 extension, global, multicenter open-label study. The purpose of this study is to evaluate long-term safety and efficacy of riliprubart in adult participants with chronic inflammatory demyelinating polyneuropathy (CIDP) who have completed Part B in 1 of 3 parent studies (PDY16744, EFC17236, or EFC18156) and wish to continue treatment with riliprubart. Up to approximately 300 participants will be enrolled to continue receiving treatment with riliprubart. The duration of participation for each participant will be up to approximately 4 years, including posttreatment follow-up. The treatment duration will be up to approximately 3 years. A participant who discontinues riliprubart treatment at any time during the study will be followed for safety for a minimum of 55 weeks after the last dose of riliprubart received.

Study Overview

• Status: Enrolling by invitation
• Conditions: Polyneuropathy, Inflammatory Demyelinating, Chronic
• Intervention / Treatment: Drug: Riliprubart Prefilled Pen (PFP)

Detailed Description

This is a single-arm study. All participants transitioning to Study LTS17261 will receive riliprubart weekly for up to 3 years, or until commercialization of riliprubart for the treatment of CIDP or termination of the riliprubart clinical development program for the treatment of CIDP, or the local availability of other options for long-term treatment with riliprubart, whichever comes first.

The total number of study visits will be 12.

• Study Type: Interventional
• Enrollment (Estimated): 300
• Phase: Phase 3

Contacts and Locations

Study Locations

• Argentina
  • Buenos Aires, Argentina, 1221
    • Investigational Site Number : 0320003
• Brazil
  • São Paulo
    • Ribeirão Preto, São Paulo, Brazil, 14049-900
      • Hospital das Clinicas da Faculdade de Medicina de Ribeirao Preto- Site Number : 0760004
• Canada
  • Quebec
    • Gatineau, Quebec, Canada, J8Y 1W2
      • Investigational Site Number : 1240001
    • Québec, Quebec, Canada, G1E 7G9
      • Investigational Site Number : 1240002
• Chile
  • Reg Metropolitana de Santiago
    • Lo Barnechea, Reg Metropolitana de Santiago, Chile, 7691236
      • Investigational Site Number : 1520003
    • Santiago, Reg Metropolitana de Santiago, Chile, 8207257
      • Investigational Site Number : 1520002
• China
  • Beijing, China, 100034
    • Investigational Site Number : 1560013
  • Beijing, China, 100053
    • Investigational Site Number : 1560005
  • Chengdu, China, 610072
    • Investigational Site Number : 1560011
  • Fuzhou, China, 350001
    • Investigational Site Number : 1560002
  • Guangzhou, China, 510000
    • Investigational Site Number : 1560012
  • Shanghai, China, 200040
    • Investigational Site Number : 1560001
  • Wuhan, China, 430030
    • Investigational Site Number : 1560003
  • Wuhan, China, 430060
    • Investigational Site Number : 1560006
• Czechia
  • Brno, Czechia, 625 00
    • Investigational Site Number : 2030004
  • Prague, Czechia, 128 08
    • Investigational Site Number : 2030001
• Denmark
  • Aarhus, Denmark, 8200
    • Investigational Site Number : 2080002
• France
  • Bordeaux, France, 33076
    • Investigational Site Number : 2500007
  • Le Kremlin-Bicêtre, France, 94270
    • Investigational Site Number : 2500001
  • Marseille, France, 13885
    • Investigational Site Number : 2500002
  • Paris, France, 75013
    • Investigational Site Number : 2500004
• Germany
  • Göttingen, Germany, 37075
    • Investigational Site Number : 2760002
  • Tübingen, Germany, 72076
    • Investigational Site Number : 2760004
• Italy
  • Pavia, Italy, 27100
    • Investigational Site Number : 3800005
  • Pisa, Italy, 56126
    • Investigational Site Number : 3800007
  • Genova
    • Genoa, Genova, Italy, 16132
      • Investigational Site Number : 3800003
  • Milano
    • Milan, Milano, Italy, 20132
      • Investigational Site Number : 3800001
    • Rozzano, Milano, Italy, 20089
      • Investigational Site Number : 3800004
  • Roma
    • Rome, Roma, Italy, 00168
      • Investigational Site Number : 3800002
• Japan
  • Toyama, Japan, 939-2716
    • Investigational Site Number : 2500005
  • Saitama
    • Higashi-Matsuyama, Saitama, Japan, 355-0005
      • Investigational Site Number : 3920012
  • Tokyo
    • Bunkyo-Ku, Tokyo, Japan, 113-8510
      • Investigational Site Number : 3920011
• Netherlands
  • Amsterdam, Netherlands, 1105 AZ
    • Investigational Site Number : 5280001
• Poland
  • Lublin Voivodeship
    • Lublin, Lublin Voivodeship, Poland, 20-954
      • Investigational Site Number : 6160001
• Portugal
  • Lisbon, Portugal, 1150-199
    • Investigational Site Number : 6200004
• Serbia
  • Belgrade, Serbia, 11000
    • Investigational Site Number : 6880001
• South Korea
  • Seoul-teukbyeolsi
    • Seoul, Seoul-teukbyeolsi, South Korea, 02841
      • Investigational Site Number : 4100003
• Spain
  • Barcelona, Spain, 08035
    • Investigational Site Number : 7240002
  • Málaga, Spain, 29010
    • Investigational Site Number : 7240008
  • Valencia, Spain, 46026
    • Investigational Site Number : 7240003
  • Catalunya [Cataluña]
    • Barcelona, Catalunya [Cataluña], Spain, 08041
      • Investigational Site Number : 7240001
  • Madrid
    • Majadahonda, Madrid, Spain, 28222
      • Investigational Site Number : 7240004
• Sweden
  • Stockholm, Sweden, 113 65
    • Investigational Site Number : 7520001
• Turkey (Türkiye)
  • Konya, Turkey (Türkiye), 42075
    • Investigational Site Number : 7920003
• United States
  • Alabama
    • Homewood, Alabama, United States, 35209
      • Alabama Neurology Associates- Site Number : 8400019
  • Kansas
    • Kansas City, Kansas, United States, 66160
      • University of Kansas Medical Center- Site Number : 8400010
  • Pennsylvania
    • Philadelphia, Pennsylvania, United States, 19104
      • Penn Medicine: University of Pennsylvania Health System- Site Number : 8400022

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

Participants are eligible to be included in the study only if all of the following criteria apply:

1. Participants with chronic inflammatory demyelinating polyneuropathy (CIDP) currently receiving riliprubart who completed treatment in Part B of Study PDY16744, Study EFC17236, or Study EFC18156. (Participants receiving riliprubart in Part C of PDY16744 are eligible after completing the Part C End of Treatment visit.)
2. All participants must agree to use contraception methods during and after the study as required. Contraceptive use by men and women participating in the study should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies.
3. Participant must be capable of giving signed informed consent as described in Appendix 1 of the protocol, which includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in this protocol.

Exclusion Criteria:

Participants are excluded from the study if any of the following criteria apply:

1. Pregnancy, defined as a positive result of a highly sensitive urine or serum pregnancy test, or lactation
2. Clinical diagnosis of systemic lupus erythematosus (SLE)
3. History of any hypersensitivity to riliprubart or any of its components, or severe allergic or anaphylactic reaction to any humanized or murine monoclonal antibody
4. Any country-related specific regulation that would prevent the participant from entering the study
5. Accommodation in an institution because of regulatory or legal order; for instance, a prisoner or participant who is legally institutionalized
6. Unsuitability for participation as judged by the Investigator, whatever the reason, including: medical or clinical condition, potential risk of participant noncompliance with study procedures, or any other clinically significant change in the participants' medical condition

The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: riliprubart; Participants receive subcutaneous injection with a riliprubart prefilled pen (PFP)	Drug: Riliprubart Prefilled Pen (PFP); Pharmaceutical form: Solution Route of administration: Subcutaneous injection; Other Names: SAR445088

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of participants having any AEs, SAEs, adverse events leading to treatment discontinuation, AESIs, and potentially clinically significant abnormalities (PCSAs) in safety laboratory tests, ECGs, and vital signs during the study period	adverse events: AEs, serious adverse events: SAEs, adverse events of special interest: AESIs, electrocardiograms: ECGs	Up to End of Study (approx. 4 years)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percentage of participants relapse-free since the first dose of riliprubart in the parent study (PDY16744, EFC17236, or EFC18156)	To estimate the relapse-free rate, time to first relapse, defined as time from first dose of riliprubart in the parent study to the first relapse since riliprubart initiation, will be derived for each participant. Relapse since riliprubart initiation is defined as increase of 1 point or more in adjusted Inflammatory Neuropathy Cause and Treatment (INCAT) disability score relative to the visit for the first dose of riliprubart in the parent study.	From first dose of riliprubart in parent study to end of treatment (up to approx. 7 years)
Percentage of participants experiencing improvement from baseline	Improvement is defined as a decrease of 1 point or more in adjusted Inflammatory Neuropathy Cause and Treatment (INCAT) disability score relative to baseline of the current study, Study LTS17261	From Baseline to 3 years
Change from baseline in adjusted Inflammatory Neuropathy Cause and Treatment (INCAT) disability score over time		From Baseline to 3 years
Change from baseline in Inflammatory Rasch-built Overall Disability Scale (I-RODS) over time		From Baseline to 3 years
Change from baseline in grip strength (kilopascals; dominant hand) over time		From Baseline to 3 years
Change from baseline in Medical Research Council-Sum Score (MRC-SS) for muscle strength over time		From Baseline to 3 years

Collaborators and Investigators

• Sponsor: Sanofi

Publications and helpful links

Helpful Links

• LTS17261 Plain Language Results Summary

Study record dates

Study Major Dates

• Study Start (Actual): April 1, 2025
• Primary Completion (Estimated): October 3, 2029
• Study Completion (Estimated): October 3, 2029

Study Registration Dates

• First Submitted: February 27, 2025
• First Submitted That Met QC Criteria: February 27, 2025
• First Posted (Actual): March 5, 2025

Study Record Updates

• Last Update Posted (Actual): June 12, 2026
• Last Update Submitted That Met QC Criteria: June 11, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Nervous System Diseases; Pathologic Processes; Neuromuscular Diseases; Chronic Disease; Disease Attributes; Autoimmune Diseases; Immune System Diseases; Peripheral Nervous System Diseases; Autoimmune Diseases of the Nervous System; Demyelinating Diseases; Polyneuropathies; Polyradiculoneuropathy; Pathological Conditions, Signs and Symptoms; Polyradiculoneuropathy, Chronic Inflammatory Demyelinating
• Other Study ID Numbers: LTS17261; U1111-1311-1432 (Other Identifier: WHO ICTRP); 2024-517032-22-00 (Registry Identifier: CTIS)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants. Further details on Sanofi's data sharing criteria, eligible studies, and process for requesting access can be found at: https://vivli.org

Drug and device information, study documents

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