A Study to Learn About Abrocitinib in Adult Patients With Moderate to Severe Atopic Dermatitis

Percentage of Participants Who Achieved IGA Score of Clear (0) or Almost Clear (1) Until End of Study

The IGA is a tool used to assess the severity of AD (excluding scalp, palms and soles) on a 5-point scale that typically ranges from 0 to 4, where 0 indicates clear (no signs of AD), 1 indicates almost clear (minimal signs of AD), 2 indicates mild AD, 3 indicates moderate AD and 4 indicates severe AD, higher scores indicated greater severity of AD. Percentage of participants with score of "Clear" (score 0) or "Almost Clear" (score 1) according to IGA were reported in this outcome measure.

Time frame: From Baseline (Day 1) up to end of study (Month 12)

Percentage of Participants With 75% Reduction From Baseline in EASI Score Until End of Study

The EASI assessed both clinical signs of AD as well as extent of disease. For body regions such as "head and neck", "trunk", "upper extremities" and "lower extremities" the extent of eczema was assessed by an area score between 0 (0% of BSA affected) and 6 (90 to 100% of BSA affected), respectively. For each area the severity of clinical signs of AD such as "erythema", "edema/papulation", "excoriation" and "lichenification" were scored from 0 to 3, respectively where 0= absent; 1= mild; 2= moderate; 3= severe. The scores for the signs were added for each area and multiplied by the respective area score. The EASI for an individual was calculated as weighted sum: 0.1\*score for head/neck + 0.3\*score for trunk + 0.2\*score for upper extremities + 0.4\*score for lower extremities. The total score ranged from 0 to 72, higher scores represented greater severity of AD. EASI 75 response was defined as at least a 75% reduction in EASI relative to baseline.

Time frame: From Baseline (Day 1) up to end of study (Month 12)

Percentage of Participants With 90% Reduction From Baseline in EASI Score Until End of Study

The EASI assessed both clinical signs of AD as well as extent of disease. For body regions such as "head and neck", "trunk", "upper extremities" and "lower extremities" the extent of eczema was assessed by an area score between 0 (0% of BSA affected) and 6 (90 to 100% of BSA affected), respectively. For each area the severity of clinical signs of AD such as "erythema", "edema/papulation", "excoriation" and "lichenification" were scored from 0 to 3, respectively where 0= absent; 1= mild; 2= moderate; 3= severe. The scores for the signs were added for each area and multiplied by the respective area score. The EASI for an individual was calculated as weighted sum: 0.1\*score for head/neck + 0.3\*score for trunk + 0.2\*score for upper extremities + 0.4\*score for lower extremities. The total score ranged from 0 to 72, higher scores represented greater severity of AD. EASI 90 response was defined as at least a 90% reduction in EASI relative to baseline.

Time frame: From Baseline (Day 1) up to end of study (Month 12)

Percentage of Participants Who Achieved IGA Score of Clear (0) or Almost Clear (1) and a Reduction of >= 2 Points From Baseline Until End of Study

The IGA is a tool used to assess the severity of AD (excluding scalp, palms and soles) on a 5-point scale that typically ranges from 0 to 4, where 0 indicates clear (no signs of AD), 1 indicates almost clear (minimal signs of AD), 2 indicates mild AD, 3 indicates moderate AD and 4 indicates severe AD, higher scores indicated greater severity of AD. Percentage of participants with score of "Clear" (score 0) or "Almost Clear" (score 1) and a reduction of \>=2 points from baseline according to IGA were reported in this outcome measure.

Time frame: From Baseline (Day 1) up to end of study (Month 12)

Percentage Change From Baseline in IGA Total Score at Months 1, 3, 6, 9 and 12

The IGA is a tool used to assess the severity of AD (excluding scalp, palms and soles) on a 5-point scale that typically ranges from 0 to 4, where 0 indicates clear (no signs of AD), 1 indicates almost clear (minimal signs of AD), 2 indicates mild AD, 3 indicates moderate AD and 4 indicates severe AD, higher scores indicated greater severity of AD.

Time frame: Baseline (Day 1), Months 1, 3, 6, 9 and 12

Percentage Change From Baseline in Scoring Atopic Dermatitis (SCORAD) Total Score at Months 1, 3, 6, 9 and 12

SCORAD total score was a validated scoring index for AD that assessed severity by combining A: extent, B: severity and C: subjective symptoms. A: a rule of 9 was used to calculate BSA affected by AD as a % of whole-BSA for each body region- head and neck 9%; upper limbs 9% each; lower limbs 18% each; anterior trunk 18%; back 18%; 1% for genitals. Score for each body region was added to determine A (0-100). B: severity of each sign (erythema; edema; oozing; excoriation; lichenification; dryness) was assessed as none =0, mild =1, moderate =2, severe =3, severity scores were added to give B (0-18). C: based on itching and sleep deprivation, each scored (0-10) where, 0= no itch/no sleeplessness and 10= worst imaginable itch/sleeplessness, scores for itch and sleeplessness were added to give C (0-20). The total score for an individual was calculated as A/5 + 7B/2 + C and ranged from 0-103; higher SCORAD scores = greater severity of AD.

Time frame: Baseline (Day 1), Months 1, 3, 6, 9 and 12

Absolute EASI Total Score at Months 1, 3, 6, 9 and 12

The EASI assessed both clinical signs of AD as well as extent of disease. For body regions such as "head and neck", "trunk", "upper extremities" and "lower extremities" the extent of eczema was assessed by an area score between 0 (0% of BSA affected) and 6 (90 to 100% of BSA affected), respectively. For each area the severity of clinical signs of AD such as "erythema", "edema/papulation", "excoriation" and "lichenification" were scored from 0 to 3, respectively where 0= absent; 1= mild; 2= moderate; 3= severe. The scores for the signs were added for each area and multiplied by the respective area score. The EASI for an individual was calculated as weighted sum: 0.1\*score for head/neck + 0.3\*score for trunk + 0.2\*score for upper extremities + 0.4\*score for lower extremities. The total score ranged from 0 to 72, higher scores represented greater severity of AD.

Time frame: At Months 1, 3, 6, 9 and 12

Percentage Change From Baseline in EASI Total Score at Months 1, 3, 6, 9 and 12

The EASI assessed both clinical signs of AD as well as extent of disease. For body regions such as "head and neck", "trunk", "upper extremities" and "lower extremities" the extent of eczema was assessed by an area score between 0 (0% of BSA affected) and 6 (90 to 100% of BSA affected), respectively. For each area the severity of clinical signs of AD such as "erythema", "edema/papulation", "excoriation" and "lichenification" were scored from 0 to 3, respectively where 0= absent; 1= mild; 2= moderate; 3= severe. The scores for the signs were added for each area and multiplied by the respective area score. The EASI for an individual was calculated as weighted sum: 0.1\*score for head/neck + 0.3\*score for trunk + 0.2\*score for upper extremities + 0.4\*score for lower extremities. The total score ranged from 0 to 72, higher scores represented greater severity of AD.

Time frame: Baseline (Day 1), Months 1, 3, 6, 9 and 12

Absolute Change From Baseline in IGA Total Score at Months 1, 3, 6, 9 and 12

The IGA is a tool used to assess the severity of AD (excluding scalp, palms and soles) on a 5-point scale that typically ranges from 0 to 4, where 0 indicates clear (no signs of AD), 1 indicates almost clear (minimal signs of AD), 2 indicates mild AD, 3 indicates moderate AD and 4 indicates severe AD, higher scores indicated greater severity of AD.

Time frame: Baseline (Day 1), Months 1, 3, 6, 9 and 12

Percentage of Participants Who Achieved at Least 4 Point Improvement on Pruritus Numerical Rating Scale (NRS) From Baseline Until End of Study

The pruritus-NRS comprised of one item and the score ranged from 0 ("no itch") to 10 ("worst imaginable itch"). Higher scores indicated greater severity. Participants were asked to rate the intensity of their average pruritus using this scale. Percentage of participants who achieved at least 4-point improvement on pruritus NRS are reported in this outcome measure.

Time frame: From Baseline (Day 1) up to end of study (Month 12)

Percentage of Participants With Pruritus NRS Score Less Than or Equal to (<=1)

The pruritus-NRS was comprised of one item and the score ranged from 0 ("no itch") to 10 ("worst imaginable itch"). Higher scores indicated greater severity. Participants were asked to rate the intensity of their average pruritus using this scale. Percentage of participants with pruritus NRS score \<=1 are reported in this outcome measure.

Time frame: From Baseline (Day 1) up to end of study (Month 12)

Percentage Change From Baseline in Peak-Pruritus (PP) NRS at Months 1, 3, 6, 9 and 12

PP NRS evaluated itching in the last 24 hours on a scale ranging from no itching (0) to worst possible itching (10). Higher scores indicated greater severity.

Time frame: Baseline (Day 1), Months 1, 3, 6, 9 and 12

Percentage Change From Baseline in Patient Oriented Eczema Measure (POEM) Score at Months 1, 3, 6, 9 and 12

POEM was a participant-reported measure that assessed AD symptoms. The participants self-evaluated the frequency of occurrence and severity of 7 symptoms (such as itching and burning of the skin) within the last week, each according to a 5-point Likert scale from 0 ("at no day") to 4 ("at all days"). The total POEM score was summed over the symptoms and ranged from 0 (clear) to 28 points (very severe), where higher score indicated greater severity.

Time frame: Baseline (Day 1), Months 1, 3, 6, 9 and 12

Percentage Change From Baseline in Medical Outcomes Study Sleep (MOS) Scale at Months 1, 3, 6, 9 and 12

The MOS-Sleep Scale is a self-administered questionnaire consisting of 12 items that assess key constructs of sleep. Instrument scoring yields 7 subscales (sleep disturbance, snoring, Sleep short of breath and headache, sleep quantity (raw scores), optimal sleep, sleep adequacy, and sleep somnolence) as well as sleep problems index I and II and all have score ranges from 0 (no sleep problems) to 100 (greater sleep problems), where higher scores indicated more sleep problems, with exception of sleep adequacy which was scored as 0 (least sleep adequacy) to 100 (better sleep adequacy) where higher scores indicated higher sleep adequacy, and optimal sleep scored as 0 (less quantity of sleep) to 24 (greater quantity of sleep), where higher scores indicated higher quantity sleep.

Time frame: Baseline (Day 1), Months 1, 3, 6, 9 and 12

Percentage Change From Baseline in Dermatology Life Quality-Index (DLQI) Score at Months 1, 3, 6, 9 and 12

The DLQI was a 10-item participant-reported measure that rated how much a participant's skin problems had affected their life over the last week assigned to the following 6 dimensions: symptoms, daily life, leisure/sport, work/school, social life/relationship and treatment. Each question was scored from 0 to 3 where, 0=best quality of life and 3=greatest possible impairment of the quality of life (QoL). The total score was calculated as sum of scores and ranged from 0 (best QoL) to 30 (worst QoL), with higher scores indicating greater impairment of quality of life.

Time frame: Baseline (Day 1), Months 1, 3, 6, 9 and 12

Percentage Change From Baseline in Hospital Anxiety and Depression Scale (HADS) Score at Months 1, 3, 6, 9 and 12

HADS was a validated 14-item questionnaire to assess states of anxiety and depression. HADS consisted of 2 subscales: HADS-Anxiety (HADS-A) scale and HADS-Depression (HADS-D) scale, each of which comprised of 7 items among adults who were physically ill. Each item was rated on a 4-point scale, with scores ranging from 0 to 3, with 0 denoting lowest and 3 denoting highest anxiety or depression level. For both subscales the total score was derived by summing up the respective 7 items with total score ranging from 0 (no presence of anxiety and depression) to 21 (severe feeling of anxiety and depression); higher score indicated greater severity of anxiety and depression.

Time frame: Baseline (Day 1), Months 1, 3, 6, 9 and 12

Percentage Change From Baseline in EuroQol Five-dimensional-five Level (EQ-5D-5L) Score at Months 1, 3, 6, 9 and 12

EQ-5D-5L was an instrument for measuring quality of life, including health benefits and health status on a visual analogue scale (VAS). EQ-5D health state profile has 5 dimensions: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Each dimension has 5 levels: 1= no problems, 2= slight problems, 3= moderate problems, 4= severe problems, and 5= extreme problems. Responses to 5 dimensions comprise a health state/a single utility index value. E.g. if a participant responds "no problems" for each 5 dimensions, then health state was coded as "11111" with a predefined index value to it. Every health state (coded as combination of responses on each of 5 dimensions) has a unique predefined utility index value assigned to it, by EuroQol. Higher (positive) scores = better health state. The VAS component rates current health state on scale from 0 (worst imaginable health state) to 100 (best imaginable health state) ; higher scores indicate a better health state.

Time frame: Baseline (Day 1), Months 1, 3, 6, 9 and 12

Treatment Satisfaction Measured by Patient Benefit Index (PBI) at Months 1, 3, 6, 9 and 12

PBI consisted of two one-sided questionnaires which were completed by participants before and after receiving a treatment. Total of 23 possible treatment goals were evaluated on importance scale from 0 ("not at all") to 4 ("very"). "Does not apply to me" was coded as "0". PBI was calculated by multiplying achieved benefits (respective PBI after baseline) with importance of the respective needs prior to therapy (PBI at baseline), dividing these products by sum of all importance items (PBI at baseline) and summing them up for all items. Total PBI score ranged from 0 (no benefit) to 4 (maximal benefit), where higher scores indicated more benefits. PBI questionnaire measured satisfaction at all points in time after baseline.

Time frame: At Months 1, 3, 6, 9 and 12

Number of Participants With Treatment Expectation Measured by PBI at Baseline

PBI consisted of two one-sided questionnaires which were completed by participants before and after receiving treatment. Total of 25 possible treatment goals were evaluated on importance scale from 0 (" not at all") to 4 ("very"), where higher scores indicated more important goals. The responses to each treatment goal included: somewhat, moderately, quite, very, does not apply to me, not answered and not at all. Treatment expectation was measured at baseline.

Time frame: At Baseline (Day 1)

Number of Days With Topical Treatment Use

Topical treatments included topical corticosteroids and topical calcineurin inhibitors. Number of days with topical treatment use was reported in this outcome measure. Number of days was calculated as date of first topical treatment - date of last topical treatment + 1.

Time frame: Months 1, 3, 6, 9 and 12

Number of Days of Emollients Use

Number of days with emollients use was calculated as: date of first emollients use - date of last emollients use + 1. The number of days with emollients use was reported in this outcome measure.

Time frame: Months 1, 3, 6, 9 and 12