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 1)

November 19, 2025 updated by: Sanofi

A Phase 3, Randomized, Double-blind, Placebo-controlled, Parallel-group, 3-arm, Multinational, Multicenter Study to Evaluate the Efficacy and Safety of Amlitelimab Monotherapy by Subcutaneous Injection in Participants Aged 12 Years and Older With Moderate-to-severe Atopic Dermatitis

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).

Study Overview

Status

Completed

Conditions

Dermatitis Atopic

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

601

Phase

Phase 3

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

Argentina
- - Buenos Aires, Argentina, 1414
    - Investigational Site Number : 0320010
  - Buenos Aires, Argentina, 1012
    - Investigational Site Number : 0320022
- Buenos Aires F.D.
  - Buenos Aires, Buenos Aires F.D., Argentina, 1028
    - Investigational Site Number : 0320023
- Tucumán Province
  - SAN Miguel de Tucumã¡n, Tucumán Province, Argentina, T4000
    - Investigational Site Number : 0320024
Australia
- New South Wales
  - Westmead, New South Wales, Australia, 2145
    - Investigational Site Number : 0360010
- Queensland
  - Woolloongabba, Queensland, Australia, 4102
    - Investigational Site Number : 0360007
- Victoria
  - Melbourne, Victoria, Australia, 3004
    - Investigational Site Number : 0360006
  - Melbourne, Victoria, Australia, 3002
    - Investigational Site Number : 0360008
  - Traralgon, Victoria, Australia, 3844
    - Investigational Site Number : 0361006
Brazil
- - Rio de Janeiro, Brazil, 22241-180
    - CCBR / IBPClin - Instituto Brasil de Pesquisa Clínica- Site Number : 0760018
  - Santo André, Brazil, 09060-650
    - Faculdade de Medicina do ABC- Site Number : 0760001
  - São Paulo, Brazil, 04020-060
    - Centro de Desenvolvimento em Estudos ClÌnicos Brasil- Site Number : 0760014
  - São Paulo, Brazil, 05403-000
    - Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo- Site Number : 0760012
- Estado de Bahia
  - Salvador, Estado de Bahia, Brazil, 41820-020
    - Centro de Pesquisas da Clínica IBIS- Site Number : 0760002
- Maranhão
  - Bequimão, Maranhão, Brazil, 65060-645
    - Hospital São Domingos- Site Number : 0760028
- Paraná
  - Curitiba, Paraná, Brazil, 80230-130
    - PUC Trials- Nucleo de Pesquisa clinica da Escola de Medicina da PUCPR- Site Number : 0760023
  - Curitiba, Paraná, Brazil, 80060-900
    - Hospital de Clinicas da Universidade Federal do Parana- Site Number : 0760022
- Rio Grande do Sul
  - Porto Alegre, Rio Grande do Sul, Brazil, 90020-090
    - Irmandade da Santa Casa de Misericórdia de Porto Alegre- Site Number : 0760005
- São Paulo
  - Sorocaba, São Paulo, Brazil, 18040-425
    - Clinica de Alergia Martti Antila- Site Number : 0760006
Canada
- Alberta
  - Edmonton, Alberta, Canada, T5K 2V4
    - Investigational Site Number : 1240031
- British Columbia
  - Surrey, British Columbia, Canada, V3R 6A7
    - Investigational Site Number : 1240040
- Ontario
  - Ajax, Ontario, Canada, L1S 7K8
    - Investigational Site Number : 1240033
  - Hamilton, Ontario, Canada, L8S 1G5
    - Investigational Site Number : 1240055
  - London, Ontario, Canada, N6A 2C2
    - Investigational Site Number : 1240029
  - Niagara Falls, Ontario, Canada, L2H 1H5
    - Investigational Site Number : 1241108
  - Ottawa, Ontario, Canada, K1H 7X8
    - Investigational Site Number : 1240034
  - Toronto, Ontario, Canada, M3B 3N1
    - Investigational Site Number : 1240013
  - Toronto, Ontario, Canada, M5A 3R6
    - Investigational Site Number : 1240035
- Quebec
  - Saint-Jérôme, Quebec, Canada, J7Z 7E2
    - Investigational Site Number : 1240043
- Saskatchewan
  - Regina, Saskatchewan, Canada, S4V 1R9
    - Investigational Site Number : 1240028
  - Saskatoon, Saskatchewan, Canada, S7K 0H6
    - Investigational Site Number : 1240036
Chile
- - Talcahuano, Chile, 2687000
    - Investigational Site Number : 1520012
- Reg Metropolitana de Santiago
  - Osorno, Reg Metropolitana de Santiago, Chile, 5311523
    - Investigational Site Number : 1520009
  - Santiago, Reg Metropolitana de Santiago, Chile, 7580206
    - Investigational Site Number : 1520002
  - Santiago, Reg Metropolitana de Santiago, Chile, 7640881
    - Investigational Site Number : 1520003
  - Santiago, Reg Metropolitana de Santiago, Chile, 8380456
    - Investigational Site Number : 1520011
  - Santiago, Reg Metropolitana de Santiago, Chile, 8380465
    - Investigational Site Number : 1520005
  - Santiago, Reg Metropolitana de Santiago, Chile, 8420383
    - Investigational Site Number : 1520001
  - Santiago, Reg Metropolitana de Santiago, Chile, 7500587
    - Investigational Site Number : 1520008
  - Santiago, Reg Metropolitana de Santiago, Chile, 8330034
    - Investigational Site Number : 1520010
- Región de Valparaíso
  - Viña del Mar, Región de Valparaíso, Chile, 2530900
    - Investigational Site Number : 1520006
China
- - Beijing, China, 100034
    - Investigational Site Number : 1560042
  - Chengdu, China, 610072
    - Investigational Site Number : 1560060
  - Chengdu, China, 610091
    - Investigational Site Number : 1560068
  - Chongqing, China, 400016
    - Investigational Site Number : 1560057
  - Chongqing, China, 400065
    - Investigational Site Number : 1560065
  - Guangzhou, China, 510630
    - Investigational Site Number : 1560058
  - Jinan, China, 250014
    - Investigational Site Number : 1560059
  - Shenzhen, China, 518026
    - Investigational Site Number : 1560064
France
- - Antony, France, 92160
    - Investigational Site Number : 2500008
  - Nantes, France, 44093
    - Investigational Site Number : 2500009
  - Paris, France, 75010
    - Investigational Site Number : 2500003
  - Reims, France, 51100
    - Investigational Site Number : 2500007
  - Romans-sur-Isère, France, 26102
    - Investigational Site Number : 2500010
Germany
- - Bad Bentheim, Germany, 48455
    - Investigational Site Number : 2760009
  - Buxtehude, Germany, 21614
    - Investigational Site Number : 2760014
  - Hamburg, Germany, 20095
    - Investigational Site Number : 2760017
  - Kiel, Germany, 24105
    - Investigational Site Number : 2762208
  - Magdeburg, Germany, 39104
    - Investigational Site Number : 2760018
  - Mainz, Germany, 55128
    - Investigational Site Number : 2760016
  - Münster, Germany, 48149
    - Investigational Site Number : 2762201
Greece
- - Athens, Greece, 124 62
    - Investigational Site Number : 3000004
  - Athens, Greece, 161 21
    - Investigational Site Number : 3000001
  - Thessaloniki, Greece, 546 42
    - Investigational Site Number : 3000002
  - Thessaloniki, Greece, 564 29
    - Investigational Site Number : 3000003
India
- - Ahmedabad, India, 380016
    - Investigational Site Number : 3560001
  - Belagavi, India, 590002
    - Investigational Site Number : 3560005
  - Bengaluru, India, 560090
    - Investigational Site Number : 3560008
  - Chandigarh, India, 160012
    - Investigational Site Number : 3560004
  - Haryāna, India, 121002
    - Investigational Site Number : 3560006
  - Kolkata, India, 700073
    - Investigational Site Number : 3560007
  - Nagpur, India, 440015
    - Investigational Site Number : 3560002
  - Pune, India, 411057
    - Investigational Site Number : 3560003
Israel
- - Afula, Israel, 1834111
    - Investigational Site Number : 3760004
  - Beersheba, Israel, 8457108
    - Investigational Site Number : 3760005
  - Haifa, Israel, 3109601
    - Investigational Site Number : 3760001
  - Jerusalem, Israel, 9112001
    - Investigational Site Number : 3760003
  - Petah Tikva, Israel, 4941492
    - Investigational Site Number : 3760002
  - Petah Tikva, Israel, 4920235
    - Investigational Site Number : 3760006
Poland
- - Krakow, Poland, 31-209
    - Investigational Site Number : 6162406
  - Lodz, Poland, 90-265
    - Investigational Site Number : 6160002
  - Lublin, Poland, 20-607
    - Investigational Site Number : 6160004
  - Olsztyn, Poland, 11-041
    - Investigational Site Number : 6160011
  - Tarnów, Poland, 33-100
    - Investigational Site Number : 6160010
  - Warsaw, Poland, 02-625
    - Investigational Site Number : 6160009
  - Warsaw, Poland, 02-962
    - Investigational Site Number : 6160007
- Pomeranian Voivodeship
  - Gdansk, Pomeranian Voivodeship, Poland, 80-546
    - Investigational Site Number : 6160006
- Silesian Voivodeship
  - Katowice, Silesian Voivodeship, Poland, 40-611
    - Investigational Site Number : 6160003
South Korea
- - Gwangju, South Korea, 61453
    - Investigational Site Number : 4100012
- Daegu
  - Daegu, Daegu, South Korea, 41944
    - Investigational Site Number : 4100008
- Gyeonggi-do
  - Ansan-si, Gyeonggi-do, South Korea, 15355
    - Investigational Site Number : 4100002
  - Seongnam-si, Gyeonggi-do, South Korea, 13620
    - Investigational Site Number : 4100014
  - Suwon, Gyeonggi-do, South Korea, 16499
    - Investigational Site Number : 4100009
- Gyeongsangnam-do
  - Yangsan, Gyeongsangnam-do, South Korea, 50612
    - Investigational Site Number : 4100003
- Incheon-gwangyeoksi
  - Bupyeong-gu, Incheon-gwangyeoksi, South Korea, 21431
    - Investigational Site Number : 4100015
- Seoul-teukbyeolsi
  - Seoul, Seoul-teukbyeolsi, South Korea, 01812
    - Investigational Site Number : 4100010
  - Seoul, Seoul-teukbyeolsi, South Korea, 03080
    - Investigational Site Number : 4100013
  - Seoul, Seoul-teukbyeolsi, South Korea, 03722
    - Investigational Site Number : 4100007
  - Seoul, Seoul-teukbyeolsi, South Korea, 05030
    - Investigational Site Number : 4100006
  - Seoul, Seoul-teukbyeolsi, South Korea, 06591
    - Investigational Site Number : 4100011
  - Seoul, Seoul-teukbyeolsi, South Korea, 07804
    - Investigational Site Number : 4100017
Taiwan
- - Kaohsiung City, Taiwan, 833
    - Investigational Site Number : 1583201
  - Taichung, Taiwan, 402
    - Investigational Site Number : 1583202
  - Taipei, Taiwan, 100
    - Investigational Site Number : 1580001
  - Taipei, Taiwan
    - Investigational Site Number : 1580003
  - Taoyuan, Taiwan, 333
    - Investigational Site Number : 1583203
United States
- Arizona
  - Scottsdale, Arizona, United States, 85260
    - Scottsdale Clinical Trials- Site Number : 8401149
- California
  - Fountain Valley, California, United States, 92708
    - First OC Dermatology- Site Number : 8401025
  - Fremont, California, United States, 94538
    - Center for Dermatology Clinical Research- Site Number : 8401018
  - Lafayette, California, United States, 94549
    - Sunwise Clinical Research- Site Number : 8401022
  - North Hollywood, California, United States, 91606
    - Carbon Health - North Hollywood - NoHo West- Site Number : 8401218
  - Northridge, California, United States, 91325
    - Northridge Clinical Trials - Northridge- Site Number : 8401080
- Florida
  - Doral, Florida, United States, 33172
    - St Jude Clinical Research- Site Number : 8401287
  - Fort Myers, Florida, United States, 33919
    - Beth Israel Deaconess Medical Center - Fort Myers- Site Number : 8401286
  - Hialeah, Florida, United States, 33012
    - Direct Helpers Research Center- Site Number : 8401056
  - Hollywood, Florida, United States, 33021
    - Encore Medical Research- Site Number : 8401030
  - Miami, Florida, United States, 33173
    - Florida International Research Center- Site Number : 8401091
  - Miami, Florida, United States, 33173
    - Miami Dermatology and Laser Research- Site Number : 8401086
  - Orlando, Florida, United States, 32806
    - Clinical Neuroscience Solutions - Orlando - South Delaney Avenue- Site Number : 8401035
- Georgia
  - Cumming, Georgia, United States, 30040
    - Cleaver Medical Group Dermatology- Site Number : 8401139
  - Macon, Georgia, United States, 31217
    - Skin Care Physicians of Georgia - Macon- Site Number : 8401034
  - Thomasville, Georgia, United States, 31792
    - Javara Research - Thomasville- Site Number : 8401189
  - Union City, Georgia, United States, 30291
    - Rophe Adult & Pediatric Medicine- Site Number : 8401289
- Kentucky
  - Louisville, Kentucky, United States, 40217
    - Skin Sciences- Site Number : 8401039
- Louisiana
  - Covington, Louisiana, United States, 70433
    - MedPharmics - Covington- Site Number : 8401137
  - Lafayette, Louisiana, United States, 70508
    - MedPharmics - Lafeyette- Site Number : 8401152
- Massachusetts
  - Boston, Massachusetts, United States, 02114
    - Massachusetts General Hospital- Site Number : 8401192
  - Needham, Massachusetts, United States, 02492
    - Metro Boston Clinical Partners- Site Number : 8401128
- Michigan
  - Dearborn, Michigan, United States, 33122
    - Revival Research - Doral- Site Number : 8401012
  - Detroit, Michigan, United States, 48202
    - Henry Ford Hospital- Site Number : 8401044
- Mississippi
  - Ridgeland, Mississippi, United States, 39157
    - SKY Integrative Medical Center/SKYCRNG - Ridgeland- Site Number : 8401058
- Missouri
  - Saint Joseph, Missouri, United States, 64506
    - MediSearch Clinical Trials- Site Number : 8401140
- Nebraska
  - Lincoln, Nebraska, United States, 68510
    - Somnos Clinical Research- Site Number : 8401203
- New York
  - Fairport, New York, United States, 14450
    - Universal Dermatology- Site Number : 8401224
  - New York, New York, United States, 10075
    - Sadick Research Group - New York - Park Avenue- Site Number : 8401050
  - The Bronx, New York, United States, 10459
    - CHEAR Center- Site Number : 8401123
- North Carolina
  - Charlotte, North Carolina, United States, 28277
    - Onsite Clinical Solutions - Charlotte - Blakeney Park Drive- Site Number : 8401124
- Oregon
  - Portland, Oregon, United States, 97201
    - Oregon Medical Research Center- Site Number : 8401017
- Pennsylvania
  - Camp Hill, Pennsylvania, United States, 17011
    - Vial Health - DermDox Dermatology- Site Number : 8401031
  - Philadelphia, Pennsylvania, United States, 19103
    - Paddington Testing Company- Site Number : 8401041
  - Philadelphia, Pennsylvania, United States, 19114
    - Clinical Research of Philadelphia- Site Number : 8401193
- South Carolina
  - Greenville, South Carolina, United States, 29607
    - Tribe Clinical Research - 525 Verdae Boulevard- Site Number : 8401225
- Texas
  - Dallas, Texas, United States, 75230
    - Dermatology Treatment and Research Center- Site Number : 8401164
  - Dallas, Texas, United States, 75254
    - Skin Specialist of Addison- Site Number : 8401208
  - San Antonio, Texas, United States, 78218
    - Texas Dermatology and Laser Specialists- Site Number : 8401131
  - Southlake, Texas, United States, 76092
    - Stryde Research - Epiphany Dermatology- Site Number : 8401185
- Utah
  - Springville, Utah, United States, 84663
    - Springville Dermatology - Springville- Site Number : 8401106
- Virginia
  - Norfolk, Virginia, United States, 23502
    - Virginia Dermatology & Skin Cancer Center- Site Number : 8401047

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

Child
Adult
Older Adult

Accepts Healthy Volunteers

Description

Inclusion Criteria:

Participants must be 12 years of age (when signing informed consent form)
Diagnosis of AD for at least 1 year (defined by the American Academy of Dermatology Consensus Criteria)
Documented history (within 6 months before screening) of either inadequate response or inadvisability to topical treatments, and/or inadequate response to systemic therapies (within 12 months before screening)
v-IGA-AD of 3 or 4 at baseline visit
EASI score of 16 or higher at baseline
AD involvement of 10% or more of BSA at baseline
Weekly average of daily PP-NRS of ≥ 4 at baseline visit.
Able and willing to comply with requested study visits and procedures
Body weight ≥25 kg

Exclusion Criteria:

Skin co-morbidity that would adversely affect the ability to undertake AD assessments
Known history of or suspected significant current immunosuppression
Any malignancies or history of malignancies prior to baseline (with the exception of non-melanoma skin cancer excised and cured >5 years prior to baseline)
History of solid organ or stem cell transplant
Any active or chronic infection including helminthic infection requiring systemic treatment within 4 weeks prior to baseline (1 week in the event of superficial skin infections)
Positive for human immunodeficiency virus (HIV), Hepatitis B or hepatitis C at screening visit
Having active tuberculosis (TB), latent TB, a history of incompletely treated TB, suspected extrapulmonary TB infection, or who are at high risk of contracting TB
Having received any of the specified therapy within the specified timeframe(s) prior to the baseline visit
In the Investigator's opinion, any clinically significant laboratory results or protocol specified laboratory abnormalities at screening
History of hypersensitivity or allergy to any of the excipients or investigational medicinal product (IMP)

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

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Interventional Model: Parallel Assignment
Masking: Quadruple

Number of Arms

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Amlitelimab dose 1 Subcutaneous injection as per protocol	Drug: Amlitelimab Injection solution SC injection Other Names: SAR445229
Experimental: Amlitelimab dose 2 Subcutaneous injection as per protocol	Drug: Amlitelimab Injection solution SC injection Other Names: SAR445229
Placebo Comparator: Placebo Subcutaneous injection as per protocol	Drug: Placebo Injection solution SC injection

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
EU, EU reference countries, and Japan: Proportion of participants with Validated Investigator Global Assessment scale for Atopic Dermatitis (vIGA-AD) of 0 (clear) or 1 (almost clear) and a reduction from baseline of ≥2 points at Week 24 Time Frame: Week 24	The vIGA-AD is an Investigator-completed assessment scale used to determine severity of AD and clinical response to treatment. It is based on a 5-point scale, ranging from 0 (clear) to 4 (severe).	Week 24
EU, EU reference countries, and Japan: Proportion of participants reaching 75% reduction from baseline in Eczema Area and Severity Index (EASI) score (EASI-75) at Week 24 Time Frame: Week 24	The EASI is an Investigator-assessed validated tool used to measure the extent (area) and severity of AD. Total score ranges from 0 to 72 with a higher score indicating increased extent and severity of AD.	Week 24
US and US reference countries: Proportion of participants with vIGA-AD of 0 (clear) or 1 (almost clear) and a reduction from baseline of ≥2 points at Week 24 Time Frame: Week 24	The vIGA-AD is an Investigator-completed assessment scale used to determine severity of AD and clinical response to treatment. It is based on a 5-point scale, ranging from 0 (clear) to 4 (severe).	Week 24

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of participants reaching EASI-75 at Week 24 (for US and US reference countries only) Time Frame: Week 24	The EASI is an Investigator-assessed validated tool used to measure the extent (area) and severity of AD. Total score ranges from 0 to 72 with a higher score indicating increased extent and severity of AD. EASI-75 is 75% reduction from baseline in EASI score.	Week 24
Proportion of participants with ≥4-point reduction in weekly average of daily Peak Pruritus-Numerical Rating Scale (PP-NRS) from baseline in participants with baseline weekly average of daily PP-NRS ≥4 Time Frame: Baseline to Week 24	The PP-NRS is a validated single item 0-10 numeric rating scale assessing peak pruritus (itch) associated with AD with 0 = no itch and 10 = worst itch imaginable.	Baseline to Week 24
Proportion of participants reaching EASI-75 Time Frame: Baseline to Week 20	The EASI is an Investigator-assessed validated tool used to measure the extent (area) and severity of AD. Total score ranges from 0 to 72 with a higher score indicating increased extent and severity of AD. EASI-75 is 75% reduction from baseline in EASI score.	Baseline to Week 20
Proportion of participants with vIGA-AD of 0 (clear) or 1 (almost clear) and a reduction from baseline of ≥2 points Time Frame: Baseline to Week 20	The vIGA-AD is an Investigator-completed assessment scale used to determine severity of AD and clinical response to treatment. It is based on a 5-point scale, ranging from 0 (clear) to 4 (severe).	Baseline to Week 20
Proportion of participants reaching EASI-90 Time Frame: Baseline to Week 24	The EASI is an Investigator-assessed validated tool used to measure the extent (area) and severity of AD. Total score ranges from 0 to 72 with a higher score indicating increased extent and severity of AD. EASI-90 is 90% reduction from baseline in EASI score.	Baseline to Week 24
Proportion of participants reaching EASI-100 Time Frame: Baseline to Week 24	The EASI is an Investigator-assessed validated tool used to measure the extent (area) and severity of AD. Total score ranges from 0 to 72 with a higher score indicating increased extent and severity of AD. EASI-100 is 100% reduction from baseline in EASI score.	Baseline to Week 24
Change in Hospital Anxiety Depression Scale (HADS) from baseline Time Frame: Baseline to Week 24	The HADS is 14-item questionnaire with two subscales: anxiety & depression. Each subscale (anxiety & depression) ranges 0-21. The total HADS score ranges 0-42 with higher score indicating a poorer state.	Baseline to Week 24
Proportion of participants with HADS subscale Anxiety (HADS-A) <8 in participants with baseline HADS-A ≥8 Time Frame: Baseline to Week 24	HADS-A score ranges 0-21 with higher score indicating a poorer state.	Baseline to Week 24
Proportion of participants with HADS subscale Depression (HADS-D) <8 in participants with HADS-D baseline ≥8 Time Frame: Baseline to Week 24	HADS-D score ranges 0-21 with higher score indicating a poorer state.	Baseline to Week 24
Proportion of participants with a reduction in weekly average of daily SP-NRS ≥4 from baseline in participants with baseline weekly average of daily SP-NRS ≥4 Time Frame: Baseline to Week 24	The SP-NRS is a single item 0-10 numeric rating scale assessing skin pain associated with AD with 0 = no pain and 10 = worst possible pain imaginable.	Baseline to Week 24
Proportion of participants with a reduction in weekly average of daily SD-NRS ≥3 from baseline in participants with Baseline weekly average of daily SD-NRS ≥3 Time Frame: Baseline to Week 24	The SD-NRS is a single item 0-10 numeric rating scale assessing sleep disturbance associated with AD with 0 = no sleep loss and 10 = did not sleep at all.	Baseline to Week 24
Percent change in EASI score from baseline Time Frame: Baseline to Week 24	The EASI is an Investigator-assessed validated tool used to measure the extent (area) and severity of AD. Total score ranges from 0 to 72 with a higher score indicating increased extent and severity of AD.	Baseline to Week 24
Percent change in weekly average of daily PP-NRS from baseline Time Frame: Baseline to Week 24	The PP-NRS is a validated single item 0-10 numeric rating scale assessing peak pruritus (itch) associated with AD with 0 = no itch and 10 = worst itch imaginable.	Baseline to Week 24
Proportion of participants reaching EASI-50 Time Frame: Baseline to Week 24	The EASI is an Investigator-assessed validated tool used to measure the extent (area) and severity of AD. Total score ranges from 0 to 72 with a higher score indicating increased extent and severity of AD. EASI-50 is 50% reduction from baseline in EASI score.	Baseline to Week 24
Proportion of participants with EASI ≤7 Time Frame: Baseline to Week 24	The EASI is an Investigator-assessed validated tool used to measure the extent (area) and severity of AD. Total score ranges from 0 to 72 with a higher score indicating increased extent and severity of AD.	Baseline to Week 24
Change in percent Body Surface Area (BSA) affected by AD from baseline Time Frame: Baseline to Week 24		Baseline to Week 24
Percent change in Scoring Atopic Dermatitis (SCORAD) index from baseline Time Frame: Baseline to Week 24	The SCORAD index is a clinical tool to evaluate the extent and severity of AD. Total score ranges from 0 (absent disease) to 103 (severe disease).	Baseline to Week 24
Proportion of participants with a reduction in SCORAD ≥ 8.7 points from baseline in participants with baseline SCORAD score ≥ 8.7 Time Frame: Baseline to Week 24	The SCORAD index is a clinical tool to evaluate the extent and severity of AD. Total score ranges from 0 (absent disease) to 103 (severe disease).	Baseline to Week 24
Proportion of participants with rescue medication use Time Frame: Baseline to Week 24		Baseline to Week 24
Percentage of participants who experienced Treatment-Emergent Adverse Events (TEAEs), experienced Treatment-Emergent Serious Adverse Events (TESAEs) and/or Treatment-Emergent Adverse Events of Special Interest (AESI) Time Frame: Baseline to Week 40		Baseline to Week 40
Serum amlitelimab concentrations Time Frame: Baseline to Week 40		Baseline to Week 40
Incidence of antidrug antibodies (ADAs) of amlitelimab Time Frame: Baseline to Week 40		Baseline to Week 40
Proportion of participants with PP-NRS 0 or 1 Time Frame: Baseline to Week 24	The PP-NRS is a validated single item 0-10 numeric rating scale assessing peak pruritus (itch) associated with AD with 0 = no itch and 10 = worst itch imaginable.	Baseline to Week 24
Proportion of participants with a reduction in DLQI ≥4 from baseline in participants with age ≥16 years old and with DLQI baseline ≥4 Time Frame: Baseline to Week 24	The DLQI is a validated 10-item questionnaire to measure dermatology-specific quality of life (QoL) in adult patients. Overall scoring ranges from 0 to 30, with a higher score indicating a poorer QoL.	Baseline to Week 24
Absolute change in weekly average of daily Skin Pain-Numerical Rating Scale (SP-NRS) from baseline Time Frame: Baseline to Week 24	The SP-NRS is a single item 0-10 numeric rating scale assessing skin pain associated with AD with 0 = no pain and 10 = worst possible pain imaginable.	Baseline to Week 24
Absolute change in weekly average of daily Sleep Disturbance-Numerical Rating Scale (SD-NRS) from baseline Time Frame: Baseline to Week 24	The SD-NRS is a single item 0-10 numeric rating scale assessing sleep disturbance associated with AD with 0 = no sleep loss and 10 = did not sleep at all.	Baseline to Week 24
Percent change in weekly average of daily SP-NRS from baseline Time Frame: Baseline to Week 24	The SP-NRS is a single item 0-10 numeric rating scale assessing skin pain associated with AD with 0 = no pain and 10 = worst possible pain imaginable.	Baseline to Week 24
Absolute change in weekly average of daily PP-NRS from baseline Time Frame: Baseline to Week 24	The PP-NRS is a validated single item 0-10 numeric rating scale assessing peak pruritus (itch) associated with AD with 0 = no itch and 10 = worst itch imaginable.	Baseline to Week 24
Absolute change in SCORAD index from baseline Time Frame: Baseline to Week 24	The SCORAD index is a clinical tool to evaluate the extent and severity of AD. Total score ranges from 0 (absent disease) to 103 (severe disease).	Baseline to Week 24
Change in Patient Oriented Eczema Measure (POEM) from baseline Time Frame: Baseline to Week 24	The POEM is a 7-item self-assessment questionnaire that assesses disease symptoms on a 5-point scale; 0 (no days) to 4 (every day in the last week). The sum of the 7 items gives the total POEM score of 0 (absent disease) to 28 (very severe). Higher scores indicated more severe disease and poor quality of life.	Baseline to Week 24
Proportion of participants with a reduction in POEM ≥4 from baseline in participants with POEM Baseline ≥4 Time Frame: Baseline to Week 24	The POEM is a 7-item self-assessment questionnaire that assesses disease symptoms on a 5-point scale; 0 (no days) to 4 (every day in the last week). The sum of the 7 items gives the total POEM score of 0 (absent disease) to 28 (very severe). Higher scores indicated more severe disease and poor quality of life.	Baseline to Week 24
Proportion of participants with a reduction in CDLQI ≥6 from baseline in participants with age ≥12 to <16 years old and with CDLQI baseline ≥6 Time Frame: Baseline to Week 24	The CDLQI is a validated 10-item questionnaire to measure dermatology-specific quality of life (QoL) in children aged 4-<16 years. Overall scoring ranges from 0 to 30, with a higher score indicating a poorer QoL.	Baseline to Week 24
Change in Dermatology Life Quality Index (DLQI) from baseline in participants with age ≥16 years old Time Frame: Baseline to Week 24	The DLQI is a validated 10-item questionnaire to measure dermatology-specific quality of life (QoL) in adult patients. Overall scoring ranges from 0 to 30, with a higher score indicating a poorer QoL.	Baseline to Week 24
Change in Children Dermatology Life Quality Index (CDLQI) from baseline in participants with age ≥12 to <16 years old Time Frame: Baseline to Week 24	The CDLQI is a validated 10-item questionnaire to measure dermatology-specific quality of life (QoL) in children aged 4-<16 years. Overall scoring ranges from 0 to 30, with a higher score indicating a poorer QoL.	Baseline to Week 24
Proportion of participants with vIGA-AD 0 (clear) or 1 (almost clear) with presence of only barely perceptible erythema (no induration/papulation, no lichenification, no oozing or crusting) and a reduction from baseline of ≥2 points Time Frame: Baseline to Week 24	The vIGA-AD is an Investigator-completed assessment scale used to determine severity of AD and clinical response to treatment. It is based on a 5-point scale, ranging from 0 (clear) to 4 (severe).	Baseline to Week 24
Proportion of participants with vIGA-AD 0 Time Frame: Week 24	The vIGA-AD is an Investigator-completed assessment scale used to determine severity of AD and clinical response to treatment. It is based on a 5-point scale, ranging from 0 (clear) to 4 (severe).	Week 24
Percent change in weekly average of daily SD-NRS Time Frame: Baseline to Week 24	The SD-NRS is a single item 0-10 numeric rating scale assessing sleep disturbance associated with AD with 0 = no sleep loss and 10 = did not sleep at all.	Baseline to Week 24

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sanofi

Investigators

Study Director: Clinical Sciences & Operations, Sanofi

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

EFC17559 Plain Language Results Summary

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

November 8, 2023

Primary Completion (Actual)

July 23, 2025

Study Completion (Actual)

November 13, 2025

Study Registration Dates

First Submitted

November 8, 2023

First Submitted That Met QC Criteria

November 8, 2023

First Posted (Actual)

November 14, 2023

Study Record Updates

Last Update Posted (Actual)

November 24, 2025

Last Update Submitted That Met QC Criteria

November 19, 2025

Last Verified

November 1, 2025

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

EFC17559 (Sanofi Identifier)
U1111-1275-9715 (Registry Identifier: ICTRP)
2022-501196-41 (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

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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Study Overview

Status

Conditions

Intervention / Treatment

Study Type

Enrollment (Actual)

Phase

Contacts and Locations

Study Locations

Participation Criteria

Eligibility Criteria

Ages Eligible for Study

Accepts Healthy Volunteers

Description

Study Plan

How is the study designed?

Design Details

Number of Arms

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

What is the study measuring?

Primary Outcome Measures

Outcome Measure

Measure Description

Time Frame

Secondary Outcome Measures

Outcome Measure

Measure Description

Time Frame

Collaborators and Investigators

Sponsor

Investigators

Publications and helpful links

Helpful Links

Study record dates

Study Major Dates

Study Start (Actual)

Primary Completion (Actual)

Study Completion (Actual)

Study Registration Dates

First Submitted

First Submitted That Met QC Criteria

First Posted (Actual)

Study Record Updates

Last Update Posted (Actual)

Last Update Submitted That Met QC Criteria

Last Verified

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

IPD Plan Description

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Studies a U.S. FDA-regulated device product

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