NCT06181435

A Study to Evaluate the Efficacy and Safety of Subcutaneous Amlitelimab Monotherapy Compared With Placebo in Participants Aged 12 Years and Older With Moderate-to-severe Atopic Dermatitis (COAST 2)

Completed Phase 3 Last updated 19 March 2026

What this trial tests

Phase 3 trial testing Amlitelimab in Dermatitis Atopic in 589 participants. Completed in 12 March 2026.

Timeline

21 December 2023

Primary endpoint
25 November 2025

12 March 2026

Quick facts

Lead sponsor	Sanofi
Phase	Phase 3
Status	Completed
Study type	INTERVENTIONAL
Allocation	randomized
Design	parallel
Masking	quadruple
Primary purpose	treatment
Enrollment	589
Start date	21 December 2023
Primary completion	25 November 2025
Estimated completion	12 March 2026
Sites	142 locations across Denmark, Italy, Japan, South Africa, Chile, Sweden, United Kingdom, Mexico

Drugs / interventions tested

• Amlitelimab — full drug profile →
• Placebo

Conditions studied

• Dermatitis Atopic — all drugs for Dermatitis Atopic →

Sponsor

Sanofi — full company profile →

Who can join

12 and older, any sex, with Dermatitis Atopic. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

This is a parallel group, Phase 3, multinational, multicenter, randomized, double-blind, placebo-controlled, 3-arm monotherapy study for treatment of participants diagnosed with moderate to severe atopic dermatitis (AD), whose disease is not adequately controlled with topical prescription therapies or when those therapies are not advisable.

The purpose of this study is to measure the efficacy and safety of treatment with amlitelimab solution for SC injection compared with placebo in participants with moderate to severe AD aged 12 years and older.

Study details include:

At the end of the treatment period, participants will have an option to enter a separate study: the blinded extension study EFC17600 (ESTUARY).

For participants not entering the blinded extension Study EFC17600 (ESTUARY), the study duration will be up to 44 weeks including a 2 to 4-week screening, a 24-week randomized double-blind period, and a 16-week safety follow-up.

For participants entering the blinded extension Study EFC17600 (ESTUARY), the study duration will be up to 28 weeks including a 2 to 4-week screening and a 24-week randomized double-blind period.

The total treatment duration will be up to 24 weeks. The total number of visits will be up to 10 visits (or 9 visits for those entering the blinded extension study EFC17600 (ESTUARY).

Publications & conference data

8 peer-reviewed publications reference this trial (live from Europe PMC):

1. Targeting TNF/TNFR superfamilies in immune-mediated inflammatory diseases.
   Veerasubramanian PK, Wynn TA, Quan J, Karlsson FJ. · · 2024 · cited 26× · PMID 39297883 · DOI 10.1084/jem.20240806
2. Targeting alarmins in asthma: From bench to clinic.
   Akenroye A, Boyce JA, Kita H. · · 2025 · cited 24× · PMID 39855362 · DOI 10.1016/j.jaci.2025.01.017
3. Emerging Biologic Therapies for the Treatment of Atopic Dermatitis.
   Alvarenga JM, Bieber T, Torres T. · · 2024 · cited 20× · PMID 39365406 · DOI 10.1007/s40265-024-02095-4
4. An OX-Tra'Ordinary Tale: The Role of OX40 and OX40L in Atopic Dermatitis.
   Sadrolashrafi K, Guo L, Kikuchi R, Hao A, et al · · 2024 · cited 19× · PMID 38607026 · DOI 10.3390/cells13070587
5. A Comprehensive Review of Biologics in Phase III and IV Clinical Trials for Atopic Dermatitis.
   Waligóra-Dziwak K, Dańczak-Pazdrowska A, Jenerowicz D. · · 2024 · cited 16× · PMID 39064040 · DOI 10.3390/jcm13144001
6. Advances in Biologic Therapies for Allergic Diseases: Current Trends, Emerging Agents, and Future Perspectives.
   Alska E, Łaszczych D, Napiórkowska-Baran K, Szymczak B, et al · · 2025 · cited 13× · PMID 40004611 · DOI 10.3390/jcm14041079
7. A Narrative Review of the OX40-OX40L Pathway as a Potential Therapeutic Target in Atopic Dermatitis: Focus on Rocatinlimab and Amlitelimab.
   Abdelhalim A, Yilmaz O, Elshaikh Berair M, Torres T. · · 2024 · cited 6× · PMID 39565527 · DOI 10.1007/s13555-024-01308-8
8. Advancing Therapeutic Strategies in Atopic Dermatitis: Emerging Targets and Personalized Approaches.
   Lo Y, Cheng TT, Huang CJ, Cheng YC, et al · · 2025 · cited 5× · PMID 40563478 · DOI 10.3390/biom15060838