IGA is an assessment scale used to determine severity of atopic dermatitis (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 was an IGA score of 0 (clear) or 1 (almost clear). Percentage of participants with IGA "0" or "1" are reported at each visit.

Here 'n' = Number of evaluable participants at the specified timepoint.

The Eczema Area and Severity Index (EASI) score was used to measure the severity and extent of AD and measures 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.

Here 'n' = Number of evaluable participants at the specified timepoint.

The Eczema Area and Severity Index (EASI) score was used to measure the severity and extent of AD and measures 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.

Here 'n' = Number of evaluable participants at the specified timepoint.

The EASI score was used to measure the severity and extent of AD and measures 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-50 responders were the participants who achieved ≥50% overall improvement in EASI score from baseline to the given time point.

Here 'n' = Number of evaluable participants at the specified timepoint.

The EASI score was used to measure the severity and extent of AD and measures 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 the given time point.

Here 'n' = Number of evaluable participants at the specified timepoint.

The EASI score was used to measure the severity and extent of AD and measures 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-90 responders were the participants who achieved ≥90% overall improvement in EASI score from baseline to the given time point.

Here 'n' = Number of evaluable participants at the specified timepoint.

The SCORAD index is a clinical tool for assessing the severity of atopic dermatitis. Extent and intensity of eczema as well as subjective signs (insomnia, etc.) are assessed and scored. Total score ranges from 0 (absent disease) to 103 (severe disease).

Here 'n' = Number of evaluable participants at the specified timepoint.

SCORAD index is a clinical tool for assessing the severity of atopic dermatitis. Extent and intensity of eczema as well as subjective signs insomnia, etc.) were assessed and scored. Total score ranged from 0 (absent disease) to 103 (severe disease). A decrease in score indicated improvement.

SCORAD-50 was defined as ≥50% reduction from baseline in SCORAD score.

Here 'n' = Number of evaluable participants at the specified timepoint.

Peak Pruritus NRS is an assessment tool used by participants to report intensity of pruritus (itch) during a 24-hour recall period. Participants were asked the following question: For maximum itch intensity: "On a scale of 0 to 10, with 0 being 'no itch' and 10 being the 'worst itch imaginable,' how would you rate your itch at the worst moment during the previous 24 hours?" For post-baseline NRS, the mean weekly NRS was calculated as the prorated average of the reported daily NRS within the week. A decrease in score indicated improvement.

Here 'n' = Number of evaluable participants at the specified timepoint.

Peak Pruritus NRS is an assessment tool used by participants to report intensity of pruritus (itch) during a 24-hour recall period. Participants were asked the following question: For maximum itch intensity: "On a scale of 0 to 10, with 0 being 'no itch' and 10 being the 'worst itch imaginable,' how would you rate your itch at the worst moment during the previous 24 hours?" For post-baseline NRS, the mean weekly NRS was calculated as the prorated average of the reported daily NRS within the week. A decrease in score indicated improvement.

Here 'n' = Number of evaluable participants at the specified timepoint.

Peak Pruritus NRS is an assessment tool used by participants to report intensity of pruritus (itch) during a 24-hour recall period. Participants were asked the following question: For maximum itch intensity: "On a scale of 0 to 10, with 0 being 'no itch' and 10 being the 'worst itch imaginable,' how would you rate your itch at the worst moment during the previous 24 hours?" For post-baseline NRS, the mean weekly NRS was calculated as the prorated average of the reported daily NRS within the week. A decrease in score indicated improvement.

Here 'n' = Number of evaluable participants at the specified timepoint.

Peak Pruritus NRS is an assessment tool used by subjects to report intensity of pruritus (itch) during a 24-hour recall period. Participants were asked the following question: For maximum itch intensity: "On a scale of 0 to 10, with 0 being 'no itch' and 10 being the 'worst itch imaginable,' how would you rate your itch at the worst moment during the previous 24 hours?" For post-baseline NRS, the mean weekly NRS was calculated as the prorated average of the reported daily NRS within the week. A decrease in score indicated improvement.

Here 'n' = Number of evaluable participants at the specified timepoint.

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

Here 'n' = Number of evaluable participants at the specified timepoint.

DLQI is a 10-item, validated questionnaire to assess the impact of AD disease symptoms and treatment on QOL; over the past week, with an overall scoring of 0 (no effect on QoL) to 30 (extremely large effect on QoL). A decrease in score indicated improvement.

Here 'n' = Number of evaluable participants at the specified timepoint.

CDLQI is a 10-item, validated questionnaire to assess the impact of AD disease symptoms and treatment on quality of life (QOL); over the past week, with an overall scoring of 0 (no effect on QoL) to 30 (extremely large effect on QoL) in children. A decrease in score indicated improvement.

Here 'n' = Number of evaluable participants at the specified timepoint.

POEM is 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) (Higher score indicative of more severe symptoms). Total score was an average of the disease symptoms assessed. A decrease in score indicated improvement.

Here 'n' = Number of evaluable participants at the specified timepoint.

The Hospital Anxiety and Depression Scale (HADS) is a screening tool designed to assess anxiety and depression. The scale consists of 14 items, divided into two subscales: Anxiety (HADS-A): 7 items; Depression (HADS-D): 7 items. The range of the total score is 0-42 (sum of HADS-A and HADS-D), with higher score indicating more severe overall psychological distress. The two subscales can be reported separately, each with a score range of 0-21, with higher score indicating more severe symptoms of anxiety or depression. A decrease in either the total score or a subscale score indicates improvement.

Here 'n' = Number of evaluable participants at the specified timepoint.

SP NRS Scale is an assessment tool used to report the intensity of a participant's pain. Participants selected the number between 0 and 10 that fit best to their worst pain intensity over the past 24 hours (0 = no pain and 10 = the worst pain imaginable). A decrease in score indicated improvement.

Here 'n' = Number of evaluable participants at the specified timepoint.

Sleep Quality NRS is an 11-point scale (0 to 10) in which 0 indicated worst possible sleep while 10 indicated best possible sleep. An increase in score indicated improvement.

Here 'n' = Number of evaluable participants at the specified timepoint.

PGID is a single 1-item questionnaire designed to assess participant's overall impression of disease severity during the past 7 days with a 5-level scale of no symptoms, mild, moderate, severe or very severe. Data are reported for the percentage of participants with a PGID response of "No symptoms" at the specified timepoints.

Here 'n' = Number of evaluable participants at the specified timepoint.

PGID is a single 1-item questionnaire designed to assess participant's overall impression of disease severity during the past 7 days with a 5-level scale of no symptoms, mild, moderate, severe or very severe. Data are reported for the percentage of participants with a PGID response of "No symptoms" or "Mild symptoms" at the specified timepoints.

Here 'n' = Number of evaluable participants at the specified timepoint.

The PGIC is a single-item questionnaire designed to assess the participant's overall sense of whether there has been a change in eczema symptoms since starting treatment as rated on a 7-point Likert scale anchored by (1) "much better" to (7) "much worse", with (4) = "no change". Data are reported for the percentage of participants who rated their eczema symptoms as "Much better" at the specified timepoints.

Here 'n' = Number of evaluable participants at the specified timepoint.

The PGIC is a single-item questionnaire designed to assess the participant's overall sense of whether there has been a change in eczema symptoms since starting treatment as rated on a 7-point Likert scale anchored by (1) "much better" to (7) "much worse", with (4) = "no change". Data are reported for the percentage of participants who rated their eczema symptoms as "Moderately better" at the specified timepoints.

Here 'n' = Number of evaluable participants at the specified timepoint.

A TEAE is any untoward medical occurrence in a participant administered a pharmaceutical product, which does not necessarily have a causal relationship with this treatment. Data are reported for the number of participants with non-herpetic skin infection TEAEs. A summary of all serious and other non-serious adverse events regardless of causality is located in the Reported Adverse Events module.

Safety Set: All participants who were enrolled in the study and received at least 1 dose of dupilumab during the study.

Serum samples were collected to measure concentrations of IgE.

Here 'n' = Number of evaluable participants at the specified timepoint.

Serum samples were collected to measure concentrations of IgE.

Here 'n' = Number of evaluable participants at the specified timepoint.

Adolescents and adults received 1 of 2 dose regimens based on age and body weight. The trough concentration of functional dupilumab in serum for the 2 dose regimens at the specified time points are presented. Participants treated and had at least one evaluable post-first-dose concentration measurement.

Pharmacokinetic (PK) Analysis Set: All participants who received any study drug and who had at least 1 non-missing PK result following the first dose of any study drug. Analysis was based on the treatment received. Overall number of participants analyzed = participants evaluable for the outcome measure. Number analyzed' = participants evaluable at specified timepoint.

The EASI score was used to measure the severity and extent of atopic dermatitis (AD) and measures 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 24.

Here 'n' = number of evaluable participants at the specified timepoint.