An Extension Study to Investigate the Long-term Safety and Tolerability of Itepekimab in Adult Participants With Inadequately Controlled Chronic Rhinosinusitis With Nasal Polyps

NCT07424144 | Enrolling By Invitation Phase 3 DMC FDA Drug

• 3 other identifiers: LTS184202025-522983-33U1111-1320-4430
• Study Type: interventional
• Target: 380
• Locations: 7 countries
• Sites: 15

Brief Summary

This is a double-blind, parallel-group, Phase 3, 2-arm study that is designed to provide additional safety information, assess the durability of treatment response, and provide additional PK and immunogenicity assessments. The primary purpose of this study is to evaluate safety and tolerability of both new or continued treatment with itepekimab 300 mg SC high dose or itepekimab 300 mg SC low dose in participants with CRSwNP having completed the intervention period of the clinical studies EFC18418 or EFC18419. A secondary purpose of this study is to provide efficacy outcomes beyond the intervention period of the parent trials EFC18418 and EFC18419. Study details include:

• The study duration will be up to 72 weeks.
• The intervention duration will be 52 weeks.
• A follow-up period of 20 weeks will be conducted.
• The number of visits will be 8 and the number of phone contacts will be 4.

Conditions

Chronic Rhinosinusitis With Nasal Polyps

Outcome Measures

Primary Outcomes (1)

• Incidence of treatment-emergent adverse events (AEs), adverse events of special interest (AESIs), serious adverse events (SAEs), AEs leading to death, and AEs leading to permanent treatment discontinuation

  All AEs (serious or nonserious) will be collected from the signing of the ICF until end of study (EOS) visit

  Baseline to EOS (Week 72)

Secondary Outcomes (6)

• Change from baseline of the parent studies (EFC18418, EFC18419) in endoscopic NPS

  Baseline to Week 52

• Change from baseline of the parent studies (EFC18418, EFC18419) in NCS

  Baseline to EOS (Week 72)

• Functional itepekimab concentration in serum

  Baseline to EOS (Week 72)

• Incidence of treatment-emergent anti-drug antibody (ADA) responses

  Baseline to EOS (Week 72)

• Proportion of participants with CRSwNP requiring systemic corticosteroid(s) (SCS) or surgery for chronic rhinosinusitis (CRS)

  Baseline up to Week 52

Study Arms (2)

Itepekimab high dose

EXPERIMENTAL

Subcutaneous (SC) administration of Itepekimab high dose for 52 weeks

Drug: Itepekimab (SAR440340)

Itepekimab low dose

EXPERIMENTAL

SC administration of Itepekimab low dose for 52 weeks

Drug: Itepekimab (SAR440340); Drug: Placebo

Interventions

Itepekimab (SAR440340) DRUG

Pharmaceutical form: Solution for injection in prefilled syringe. Route of administration: Subcutaneous

Also known as: REGN3500

Itepekimab high dose; Itepekimab low dose

Placebo DRUG

Pharmaceutical form: Solution for injection in prefilled syringe. Route of administration: Subcutaneous

Itepekimab low dose

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Participants with CRSwNP who completed the 52-weeks intervention period in a previous itepekimab CRSwNP Phase 3 clinical study (ie, EFC18418 or EFC18419) and for which an EOT visit occurred no later than 5 days before the enrollment visit of this study.
• A female participant is eligible to participate if she is not pregnant or breastfeeding, and at least one of the following conditions applies:
• Is not a women of childbearing potential (WOCBP), OR
• Is a WOCBP who agrees to follow the contraceptive guidance during the intervention period and for at least 20 weeks after the last dose of study intervention.

You may not qualify if:

• Participants are excluded from the study if any of the following criteria apply:
• Diagnosis of a malignancy during parent study, except a squamous or basal cell carcinoma of the skin.
• Any opportunistic infection during the parent study, such as tuberculosis (TB) or other infections whose nature or course may suggest an immunocompromised status.
• Anaphylactic reactions or systemic allergic reactions that are related to IMP and require treatment during the parent study.
• Any other situation that led to a permanent premature IMP discontinuation in parent trials.
• The above information is not intended to contain all considerations relevant to a participant's potential participation in a clinical trial.

Sponsors & Collaborators

• Sanofi: lead
• Regeneron Pharmaceuticals: collaborator

Study Sites (15)

Velocity Clinical Research - San Diego- Site Number : 8402041

La Mesa, California, 91942, United States

Location

Allergy, Asthma and Clinical Research- Site Number : 8402002

Oklahoma City, Oklahoma, 73120, United States

Location

Investigational Site Number : 0362001

Spearwood, Western Australia, 6163, Australia

Location

Investigational Site Number : 1241001

Québec, Quebec, G1V 4G5, Canada

Location

Investigational Site Number : 1521003

Talca, Maule Region, 3465584, Chile

Location

Investigational Site Number : 1522003

Santiago, Reg Metropolitana de Santiago, 7500505, Chile

Location

Investigational Site Number : 1521002

Santiago, Reg Metropolitana de Santiago, 7500692, Chile

Location

Investigational Site Number : 1562001

Beijing, 100730, China

Location

Investigational Site Number : 1562004

Chengdu, 610017, China

Location

Investigational Site Number : 1562008

Jingzhou, 434020, China

Location

Investigational Site Number : 1562006

Shenyang, 110004, China

Location

Investigational Site Number : 1562010

Taiyuan, 030001, China

Location

Investigational Site Number : 4101001

Seoul, Seoul-teukbyeolsi, 07061, South Korea

Location

Investigational Site Number : 8262002

Wigan, Lancashire, Wn6 9ep, United Kingdom

Location

Investigational Site Number : 8261004

Bradford, BD9 6RJ, United Kingdom

Location

Related Links

• LTS18420 Plain Language Results Summary

MeSH Terms

Interventions

itepekimab

Study Officials

• Clinical Sciences & Operations

  Sanofi

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 13, 2026
• First Posted: February 20, 2026
• Study Start: March 12, 2026
• Primary Completion (Estimated): December 12, 2028
• Study Completion (Estimated): December 12, 2028
• Last Updated: May 27, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will share

Locations

KR (1); GB (2); CN (5); AU (1); US (2); CA (1); CL (3)