Study to Assess the Efficacy and Long-term Safety of Dupilumab (REGN668/SAR231893) in Adult Participants With Moderate-to-Severe Atopic Dermatitis

Percentage of Participants With Investigator's Global Assessment (IGA) Score of "0" or "1" and Reduction From Baseline of ≥2 Points at Week 52

IGA is an assessment scale used to determine severity of AD and clinical response to treatment on a 5-point scale (0 = clear; 1 = almost clear; 2 = mild; 3 = moderate; 4 = severe) based on erythema and papulation/infiltration. Therapeutic response is an IGA score of 0 (clear) or 1 (almost clear). Participants with IGA score of "0" or "1" and a reduction from baseline of ≥2 points at Week 52 were reported.

Time frame: Baseline to Week 52

Percentage of Participants With Eczema Area and Severity Index-75 (EASI-75) (≥75% Improvement From Baseline) at Week 52

The EASI score was used to measure the severity and extent of AD and measured erythema, infiltration, excoriation and lichenification on 4 anatomic regions of the body: head, trunk, upper and lower extremities. The total EASI score ranges from 0 (minimum) to 72 (maximum) points, with the higher scores reflecting the worse severity of AD. EASI-75 responders were the participants who achieved ≥75% overall improvement in EASI score from baseline to Week 52.

Time frame: Baseline to Week 52

Percent Change From Baseline in Weekly Average of Peak Daily Pruritus Numerical Rating Scale (NRS) Score to Week 16

Pruritus NRS was an assessment tool that was used to report the intensity of a participant's pruritus (itch), both maximum and average intensity, during a 24-hour recall period. Participants were asked the following question: how would a participant rate his itch at the worst moment during the previous 24 hours (for maximum itch intensity on a scale of 0 - 10 \[0 = no itch; 10 = worst itch imaginable\]).

Time frame: Baseline to Week 16

Percentage of Participants With Improvement (Reduction ≥4 Points) of Weekly Average of Peak Daily Pruritus Numerical Rating Scale (NRS) Score From Baseline to Week 52

Pruritus NRS was an assessment tool that was used to report the intensity of a participant's pruritus (itch), both maximum and average intensity, during a 24-hour recall period. Participants were asked the following question: how would a participant rate his itch at the worst moment during the previous 24 hours (for maximum itch intensity on a scale of 0 - 10 \[0 = no itch; 10 = worst itch imaginable\]). Participants achieving a reduction of ≥4 points from baseline in weekly average of peak daily pruritus NRS score at Week 52 were reported.

Time frame: Baseline to Week 52

Percentage of Participants With Improvement (Reduction ≥3 Points) of Weekly Average of Peak Daily Pruritus Numerical Rating Scale (NRS) Score From Baseline to Week 52

Pruritus NRS was an assessment tool that was used to report the intensity of a participant's pruritus (itch), both maximum and average intensity, during a 24-hour recall period. Participants were asked the following question: how would a participant rate his itch at the worst moment during the previous 24 hours (for maximum itch intensity on a scale of 0 - 10 \[0 = no itch; 10 = worst itch imaginable\]). Participants achieving a reduction of ≥3 points from baseline in weekly average of peak daily pruritus NRS score at Week 52 were reported.

Time frame: Baseline to Week 52

Percentage of Participants With Improvement (Reduction ≥4 Points) of Weekly Average of Peak Daily Pruritus Numerical Rating Scale (NRS) Score From Baseline to Week 24

Pruritus NRS was an assessment tool that was used to report the intensity of a participant's pruritus (itch), both maximum and average intensity, during a 24-hour recall period. Participants were asked the following question: how would a participant rate his itch at the worst moment during the previous 24 hours (for maximum itch intensity on a scale of 0 - 10 \[0 = no itch; 10 = worst itch imaginable\]). Participants achieving a reduction of ≥4 points from baseline in weekly average of peak daily pruritus NRS score at Week 24 were reported.

Time frame: Baseline to Week 24

Percentage of Participants With Improvement (Reduction ≥4 Points) of Weekly Average of Peak Daily Pruritus Numerical Rating Scale (NRS) Score From Baseline to Week 4

Pruritus NRS was an assessment tool that was used to report the intensity of a participant's pruritus (itch), both maximum and average intensity, during a 24-hour recall period. Participants were asked the following question: how would a participant rate his itch at the worst moment during the previous 24 hours (for maximum itch intensity on a scale of 0 - 10 \[0 = no itch; 10 = worst itch imaginable\]). Participants achieving a reduction of ≥4 points from baseline in weekly average of peak daily pruritus NRS score at Week 4 were reported.

Time frame: Baseline to Week 4

Percentage of Participants With Improvement (Reduction ≥4 Points) of Weekly Average of Peak Daily Pruritus Numerical Rating Scale (NRS) Score From Baseline to Week 2

Pruritus NRS was an assessment tool that was used to report the intensity of a participant's pruritus (itch), both maximum and average intensity, during a 24-hour recall period. Participants were asked the following question: how would a participant rate his itch at the worst moment during the previous 24 hours (for maximum itch intensity on a scale of 0 - 10 \[0 = no itch; 10 = worst itch imaginable\]). Participants achieving a reduction of ≥4 points from baseline in weekly average of peak daily pruritus NRS score at Week 2 were reported.

Time frame: Baseline to Week 2

Change From Baseline in Weekly Average of Peak Daily Pruritus Numerical Rating Scale (NRS) Score to Week 16

Pruritus NRS was an assessment tool that was used to report the intensity of a participant's pruritus (itch), both maximum and average intensity, during a 24-hour recall period. Participants were asked the following question: how would a participant rate his itch at the worst moment during the previous 24 hours (for maximum itch intensity on a scale of 0 - 10 \[0 = no itch; 10 = worst itch imaginable\]).

Time frame: Baseline to Week 16

Percent Change From Baseline in Eczema Area and Severity Index (EASI) Score to Week 16

The EASI score was used to measure the severity and extent of AD and measured erythema, infiltration, excoriation and lichenification on 4 anatomic regions of the body: head, trunk, upper and lower extremities. The total EASI score ranges from 0 (minimum) to 72 (maximum) points, with the higher scores reflecting the worse severity of AD.

Time frame: Baseline to Week 16

Change From Baseline in Percent Body Surface Area (BSA) Affected by Atopic Dermatitis to Week 16

BSA affected by AD was assessed for each section of the body (the possible highest score for each region was: head and neck \[9%\], anterior trunk \[18%\], back \[18%\], upper limbs \[18%\], lower limbs \[36%\], and genitals \[1%\]). It was reported as a percentage of all major body sections combined.

Time frame: Baseline to Week 16

Percent Change From Baseline in the SCORing Atopic Dermatitis (SCORAD) Score to Week 16

SCORAD was a clinical tool for assessing the severity of AD developed by the European Task Force on Atopic Dermatitis (Severity scoring of atopic dermatitis: the SCORAD index). Consensus Report of the European Task Force on Atopic Dermatitis. Dermatology (Basel) 186 (1): 23-31. 1993. Extent and intensity of eczema as well as subjective signs (insomnia, etc.) were assessed and scored. Total score ranges from 0 (absent disease) to 103 (severe disease).

Time frame: Baseline to Week 16

Change From Baseline in Dermatology Life Quality Index (DLQI) to Week 16

The DLQI was a 10-item, validated questionnaire used in clinical practice and clinical trials to assess the impact of AD disease symptoms and treatment on quality of life (QOL). The 10 questions assessed QOL over the past week, with an overall scoring of 0 (absent disease) to 30 (severe disease); a high score was indicative of a poor QOL.

Time frame: Baseline to Week 16

Change From Baseline in Patient Oriented Eczema Measure (POEM) to Week 16

The POEM was a 7-item questionnaire that assessed disease symptoms (dryness, itching, flaking, cracking, sleep loss, bleeding and weeping) with a scoring system of 0 (absent disease) to 28 (severe disease) (high score indicative of poor quality of life \[QOL\]).

Time frame: Baseline to Week 16

Change From Baseline in Hospital Anxiety Depression Scale (HADS) to Week 16

HADS is a fourteen item scale. Seven of the items relate to anxiety and seven items relate to depression. Each item on the questionnaire scored from 0 (minimum score) - 3 (maximum score) and this means that a person can score between 0 (no symptoms) and 21 (severe symptoms) for either anxiety or depression. Cut-offs for identifying psychiatric distress has been reported as 7 to 8 for possible presence, 10 to 11 for probable presence, and 14 to 15 for severe anxiety or depression.

Time frame: Baseline to Week 16

Percent Change From Baseline in Total Global Individual Signs Score (GISS) to Week 16

Individual components of the AD lesions (erythema, infiltration/ papulation, excoriations, and lichenification) were rated globally (each assessed for the whole body, not by anatomical region) on a 4-point scale (0= none, 1= mild, 2= moderate and 3= severe) using the EASI severity grading criteria. Total score ranges from 0 (absent disease) to 12 (severe disease).

Time frame: Baseline to Week 16

Proportion of Topical Atopic Dermatitis Medication-Free Days Through Week 52

Proportion of topical AD medication-free days through Week 52 was calculated as the number of days that a participant used neither topical corticosteroid (TCS)/ topical calcineurin inhibitors (TCI) nor system rescue therapy divided by the study days of each period.

Time frame: Baseline to Week 52

Percent Change From Baseline in Weekly Average of Peak Daily Pruritus Numerical Rating Scale (NRS) Score to Week 2

Pruritus NRS was an assessment tool that was used to report the intensity of a participant's pruritus (itch), both maximum and average intensity, during a 24-hour recall period. Participants were asked the following question: how would a participant rate his itch at the worst moment during the previous 24 hours (for maximum itch intensity on a scale of 0 - 10 \[0 = no itch; 10 = worst itch imaginable\]).

Time frame: Baseline to Week 2

Percent Change From Baseline in Eczema Area and Severity Index (EASI) Score to Week 52

The EASI score was used to measure the severity and extent of AD and measured erythema, infiltration, excoriation and lichenification on 4 anatomic regions of the body: head, trunk, upper and lower extremities. The total EASI score ranges from 0 (minimum) to 72 (maximum) points, with the higher scores reflecting the worse severity of AD.

Time frame: Baseline to Week 52

Change From Baseline in Percent Body Surface Area (BSA) Affected by Atopic Dermatitis to Week 52

BSA affected by AD was assessed for each section of the body (the possible highest score for each region was: head and neck \[9%\], anterior trunk \[18%\], back \[18%\], upper limbs \[18%\], lower limbs \[36%\], and genitals \[1%\]). It was reported as a percentage of all major body sections combined.

Time frame: Baseline to Week 52

Percent Change From Baseline in the SCORing Atopic Dermatitis (SCORAD) Score to Week 52

SCORAD was a clinical tool for assessing the severity of AD developed by the European Task Force on Atopic Dermatitis (Severity scoring of atopic dermatitis: the SCORAD index). Consensus Report of the European Task Force on Atopic Dermatitis. Dermatology (Basel) 186 (1): 23-31. 1993. Extent and intensity of eczema as well as subjective signs (insomnia, etc.) were assessed and scored. Total score ranges from 0 (absent disease) to 103 (severe disease).

Time frame: Baseline to Week 52

Percent Change From Baseline in Global Individual Signs Score (GISS) to Week 52

Individual components of the AD lesions (erythema, infiltration/ papulation, excoriations, and lichenification) were rated globally (each assessed for the whole body, not by anatomical region) on a 4-point scale (0= none, 1= mild, 2= moderate and 3= severe) using the EASI severity grading criteria. Total score ranges from 0 (absent disease) to 12 (severe disease).

Time frame: Baseline to Week 52

Change From Baseline in Dermatology Life Quality Index (DLQI) to Week 52

The DLQI was a 10-item, validated questionnaire used in clinical practice and clinical trials to assess the impact of AD disease symptoms and treatment on quality of life (QOL). The 10 questions assessed QOL over the past week, with an overall scoring of 0 (absent disease) to 30 (severe disease); a high score was indicative of a poor QOL.

Time frame: Baseline to Week 52

Change From Baseline in Patient Oriented Eczema Measure (POEM) to Week 52

The POEM was a 7-item questionnaire that assesses disease symptoms (dryness, itching, flaking, cracking, sleep loss, bleeding and weeping) with a scoring system of 0 (absent disease) to 28 (severe disease) (high score indicative of poor quality of life \[QOL\]).

Time frame: Baseline to Week 52

Change From Baseline in Hospital Anxiety Depression Scale (HADS) to Week 52

HADS is a fourteen item scale. Seven of the items relate to anxiety and seven items relate to depression. Each item on the questionnaire is scored from 0 (minimum score) - 3 (maximum score) and this means that a person can score between 0 (no symptoms) and 21 (severe symptoms) for either anxiety or depression. Cut-offs for identifying psychiatric distress has been reported as 7 to 8 for possible presence, 10 to 11 for probable presence, and 14 to 15 for severe anxiety or depression.

Time frame: Baseline to Week 52

Number of Flares Through Week 52

Atopic dermatitis (AD) flares were defined as worsening of the disease that required escalation/intensification of AD treatment. Number of flares occurred in the participants starting from first dose through Week 52 were reported.

Time frame: Baseline up to Week 52

Number of Serious Treatment Emergent Adverse Events (TEAEs) Leading to Study Drug Discontinuation Through Week 52

Any untoward medical occurrence in a participant who received investigational medicinal product (IMP) was considered an AE without regard to possibility of causal relationship with this treatment. A Serious adverse event (SAE) was defined as any untoward medical occurrence that resulted in any of the following outcomes: death, life-threatening, required initial or prolonged in-patient hospitalization, persistent or significant disability/incapacity, congenital anomaly/birth defect, or considered as medically important event. Any TEAE included participants with both serious and non-serious AEs.

Time frame: Baseline up to Week 52

Percentage of Participants With Skin Infection Treatment Emergent Adverse Events (TEAEs) (Excluding Herpetic Infections) From Baseline Through Week 52

Any untoward medical occurrence in a participants who received IMP was considered an AE without regard to possibility of causal relationship with this treatment. TEAEs were defined as AEs that developed or worsened or became serious during on-treatment period (time from the first dose of study drug up to end of treatment at Week 52). Any TEAE included participants with both serious and non-serious AEs. Skin infection TEAEs were identified based on blinded adjudication of all reported TEAEs under the 2 primary System Organ Classes (SOC): SOC = "Infection and Infestations" or SOC = "Skin and Subcutaneous Tissue Disorders". Blinded adjudication was performed and finalized by the study medical monitor before database lock.

Time frame: Baseline up to Week 52

Number of Skin Infection TEAEs (Excluding Herpetic Infections) From Baseline Through Week 52

Any untoward medical occurrence in a participant who received IMP was considered an AE without regard to possibility of causal relationship with this treatment. TEAEs were defined as AEs that developed or worsened or became serious during on-treatment period (time from the first dose of study drug up to end of treatment at Week 52). Any TEAE included participants with both serious and non-serious AEs. Skin infection TEAEs were identified based on blinded adjudication of all reported TEAEs under the 2 primary System Organ Classes (SOC): SOC = "Infection and Infestations" or SOC = "Skin and Subcutaneous Tissue Disorders". Blinded adjudication was performed and finalized by the study medical monitor before database lock.

Time frame: Baseline up to Week 52

Percentage of Participants With Skin Infection Treatment Emergent Adverse Events (TEAEs) (Excluding Herpetic Infections) Requiring Systemic Treatment From Baseline Through Week 52

Any untoward medical occurrence in a participant who received IMP was considered an AE without regard to possibility of causal relationship with this treatment. TEAEs were defined as AEs that developed or worsened or became serious during on-treatment period (time from the first dose of study drug up to end of treatment at Week 52). Any TEAE included participants with both serious and non-serious AEs. Skin infection TEAEs were identified based on blinded adjudication of all reported TEAEs under the 2 primary System Organ Classes (SOC): SOC = "Infection and Infestations" or SOC = "Skin and Subcutaneous Tissue Disorders". Blinded adjudication was performed and finalized by the study medical monitor before database lock.

Time frame: Baseline up to Week 52

Number of Skin Infection Treatment Emergent Adverse Events (TEAEs) (Excluding Herpetic Infections) Requiring Systemic Treatment From Baseline Through Week 52

Any untoward medical occurrence in a participant who received IMP was considered an AE without regard to possibility of causal relationship with this treatment. TEAEs were defined as AEs that developed or worsened or became serious during on-treatment period (time from the first dose of study drug up to end of treatment at Week 52). Any TEAE included participants with both serious and non-serious AEs. Skin infection TEAEs were identified based on blinded adjudication of all reported TEAEs under the 2 primary System Organ Classes (SOC): SOC = "Infection and Infestations" or SOC = "Skin and Subcutaneous Tissue Disorders". Blinded adjudication was performed and finalized by the study medical monitor before database lock.

Time frame: Baseline up to Week 52