A Phase 2 interventional study of Itepekimab (SAR440340) and Placebo in Chronic Rhinosinusitis Without Nasal Polyps, sponsored by Sanofi. Completed at 57 sites in 13 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-08-25.
Sponsored by Sanofi · Phase 2, Interventional, and Treatment
ACT18421 is a multinational, randomized, double-blind, placebo-controlled, parallel-group, Phase 2 study with 3 treatment groups. The purpose of the study is to evaluate the efficacy, safety and tolerability of 2 dosing regimens of itepekimab compared to placebo in male and female participants with chronic rhinosinusitis without nasal polyps (CRSsNP) aged 18 years of age and older.
Study details include:
Sanofi is the lead sponsor of 1,508 studies on the registry; 90 are open to participants now.
Of its 198 completed or terminated interventional studies of FDA-regulated products, 118 (60%) have results posted.
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Participants must have at least one of the following features:
A female participant is eligible to participate if she is not pregnant or breastfeeding, and at least 1 of the following conditions applies:
Exclusion Criteria:
Participants are excluded from the study if any of the following criteria apply:
The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.
Subcutaneous (SC) administration of Itepekimab high dose for 24 weeks
Drug: Itepekimab (SAR440340) · Drug: Mometasone furoate nasal spray (MFNS)
SC administration of Itepekimab low dose for 24 weeks
Drug: Itepekimab (SAR440340) · Drug: Placebo · Drug: Mometasone furoate nasal spray (MFNS)
SC administration of matching placebo for 24 weeks
Drug: Placebo · Drug: Mometasone furoate nasal spray (MFNS)
Pharmaceutical form: Solution for injection in prefilled syringe. Route of administration: Subcutaneous
Also known as: REGN3500
Pharmaceutical form: Solution for injection in prefilled syringe. Route of administration: Subcutaneous
Pharmaceutical form: Solution for administration via spray pump. Route of administration: Intranasal spray
Change from baseline in sinus (maxillary, ethmoid) percent opacification volume assessed by CT scan
Change from baseline in sinus inflammation as assessed by Computerized Tomography (CT) scan of the sinuses in the itepekimab-- compared to placebo-- treated study participants on the background of intranasal corticosteroid (INCS).
Time frame: Baseline to End of Treatment (EOT) (Week 24)
Change from baseline in the sTSS
The CRSsNP sinus Total Symptom Score (sTSS) is a composite score derived from nasal congestion (NC), anterior/posterior rhinorrhea, and facial pain/pressure. The total score ranges from 0 to 9 with higher scores indicating greater overall symptom severity.
Time frame: Baseline to EOT (Week 24)
Change from baseline in nasal congestion (NC) severity score using the CRSsNP daily ediary
The CRSsNP sinonasal symptom diary is designed to assess the severity of CRS sinonasal symptoms on daily basis. These symptoms include NC/obstruction, anterior rhinorrhea and posterior rhinorrhea, facial pain/pressure, loss of smell, and headache. Each of the individual items of the diary are scored from 0 ("No symptoms") to 3 ("Severe symptoms - symptoms that are hard to tolerate, cause interference with activities or daily living"). Higher scores on the items of the individual symptoms denote greater symptom severity.
Time frame: Baseline to EOT (Week 24)
Change from baseline in anterior/posterior rhinorrhea severity score using the CRSsNP daily ediary
The CRSsNP sinonasal symptom diary is designed to assess the severity of CRS sinonasal symptoms on daily basis. These symptoms include NC/obstruction, anterior rhinorrhea and posterior rhinorrhea, facial pain/pressure, loss of smell, and headache. Each of the individual items of the diary are scored from 0 ("No symptoms") to 3 ("Severe symptoms - symptoms that are hard to tolerate, cause interference with activities or daily living"). Higher scores on the items of the individual symptoms denote greater symptom severity.
Time frame: Baseline to EOT (Week 24)
Change from baseline in facial pain/pressure severity score using the CRSsNP daily ediary
The CRSsNP sinonasal symptom diary is designed to assess the severity of CRS sinonasal symptoms on daily basis. These symptoms include NC/obstruction, anterior rhinorrhea and posterior rhinorrhea, facial pain/pressure, loss of smell, and headache. Each of the individual items of the diary are scored from 0 ("No symptoms") to 3 ("Severe symptoms - symptoms that are hard to tolerate, cause interference with activities or daily living"). Higher scores on the items of the individual symptoms denote greater symptom severity.
Time frame: Baseline to EOT (Week 24)
Change from baseline in loss of smell severity score using the CRSsNP daily ediary
The CRSsNP sinonasal symptom diary is designed to assess the severity of CRS sinonasal symptoms on daily basis. These symptoms include NC/obstruction, anterior rhinorrhea and posterior rhinorrhea, facial pain/pressure, loss of smell, and headache. Each of the individual items of the diary are scored from 0 ("No symptoms") to 3 ("Severe symptoms - symptoms that are hard to tolerate, cause interference with activities or daily living"). Higher scores on the items of the individual symptoms denote greater symptom severity.
Time frame: Baseline to EOT (Week 24)
Change from baseline in SNOT-22 total score
The Sino-Nasal Outcome Test-22-Items (SNOT-22) is a patient-reported outcome questionnaire designed to assess the impact of chronic rhinosinusitis (CRS) on patients' Health-Related Quality of Life (HRQoL). It has 22 items covering symptoms, social/emotional impact, productivity, and sleep consequences of CRS. A global score ranges from 0 to 110 with higher score indicating greater rhinosinusitis-related health burden.
Time frame: Baseline to EOT (Week 24)
Change from baseline in sinus opacification as measured by the Lund-Mackay (LMK) score and the modified LMK score
The LMK and the modified LMK scoring systems are based on points given for degree of opacification, which are applied to the maxillary, anterior ethmoid, posterior ethmoid, sphenoid, frontal sinus on each side. The osteomeatal complex is graded as 0 = not occluded, or 2 = occluded, deriving a maximum score of 12 per side.
Time frame: Baseline to EOT (Week 24)
Incidence of treatment-emergent adverse events (TEAEs), treatment-emergent adverse events of special interest (TEAESIs), treatment emergent serious adverse events (TESAEs), and TEAEs leading to intervention discontinuation
Time frame: Baseline up to End of Study (EOS) (Week 44)
Itepekimab concentration in serum
Time frame: Baseline to EOS (Week 44)
Incidence of treatment-emergent (TE) anti-itepekimab antibodies responses
Time frame: Baseline to EOS (Week 44)
Plan to share: Yes — 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
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