Placebo matching to etanercept administered by subcutaneous injection once a week

The sPGA is a static measurement based on induration, erythema, and scaling. The sPGA is assessed on a scale from 0 to 5:

0 = clear (no evidence of plaque elevation, erythema or scaling)

1. = almost clear (minimal plaque elevation, erythema or scaling)
2. = mild (mild plaque elevation or scaling, light red coloration)
3. = moderate (moderate plaque elevation, scaling, light red coloration)
4. = marked (marked plaque elevation, thick, non-tenacious scale predominates, bright red coloration)
5. = severe (severe plaque elevation, very thick tenacious scaling, dusky to deep red coloration).

Participants who entered the escape arm or had missing data at week 12 were considered non-responders.

The Children's Dermatology Life Quality Index (CDLQI) was used to assess the impact of psoriasis on subject health-related quality of life. The CDLQI has 10 items assessing health-related quality of life (HRQOL) in patients with skin disease each measured on a scale from 0 (Not at all) to 3 (Very much). The total score ranges from 0 to 30, with lower scores indicating better quality of life. If participants were ≥ 13 years old, the text instrument was completed by the participants themselves. Participants ≥ 8 but < 13 years old used the cartoon version of the instrument and participants ≤ 7 years old used the cartoon version of the instrument completed with help from the parents or caregivers.

Percent improvement from baseline = (Baseline Value - Post-baseline Value) / Baseline Value * 100.

Participants who entered the escape arm or who had missing data at week 12 were considered to have 0% improvement from baseline.

The percentage of participants who achieved 90% or greater improvement from baseline in PASI score after 12 weeks of treatment. The PASI score is a combination of the intensity of psoriasis, assessed by erythema (reddening), induration (plaque thickness) and desquamation (scaling) scored on a scale from 0 (none) to 4 (very severe), together with the percentage of the area affected, rated on a scale from 0 (no involvement) to 6 (90% to 100% involvement). PASI scoring is performed at four body areas, the head, arms, trunk, and legs. The total PASI score ranges from 0 to 72. The higher the total score, the more severe the disease.

Participants who entered the escape arm or had missing data at week 12 were considered non-responders.

The severity assessment for adverse events and infections was done using the Common Toxicity Criteria (CTC) Version 2.0, where Grade 0 = no toxicity, Grade 1 = mild toxicity, Grade 2 = moderate toxicity, Grade 3 = severe toxicity, Grade 4 = life-threatening toxicity.

Serious adverse events were any events that suggested a significant hazard or side effect, regardless of the investigator's or sponsor's opinion on the relationship to study medication. These included, but were not limited to, events at any dose that were fatal, life threatening, required in-patient hospitalization or prolonged hospitalization, were a persistent or significant disability/incapacity, or were a congenital abnormality/birth defect. Medical events that jeopardized a participant, required intervention to prevent one of the above outcomes, or resulted in urgent investigation could be considered serious.

Serum concentrations for etanercept were measured by using a validated enzyme-linked immunosorbent assay (ELISA). The lower limit of quantification (LLOQ) was 0.627 ng/mL.

Includes participants who completed week 36 with a PASI response

Total of all reporting groups

The Psoriasis Area and Severity Index (PASI) score is a combination of the intensity of psoriasis, assessed by erythema (reddening), induration (plaque thickness) and desquamation (scaling) scored on a scale from 0 (none) to 4 (very severe), together with the percentage of the area affected, rated on a scale from 0 (no involvement) to 6 (90% to 100% involvement). PASI scoring is performed at four body areas, the head, arms, trunk, and legs. The total PASI score ranges from 0 to 72. The higher the total score, the more severe the disease.

Participants randomized to receive 0.8 mg/kg etanercept administered by subcutaneous injection once a week during the 12-week, double-blind, placebo-controlled treatment period (day 1 to week 12). Participants with a more than 50% worsening (ie, increase) in PASI score at or after week 4 compared with baseline and an increase of at least 4 points at 1 visit, or with an increase of more than 25% and by a minimum of 4 points at each of two consecutive visits, could escape to etanercept 0.8 mg/kg once a week up to week 12.

The percentage of participants who achieved 50% or greater improvement from baseline in PASI score after 12 weeks of treatment. PASI is a combination of the intensity of psoriasis, assessed by erythema (reddening), induration (plaque thickness) and desquamation (scaling) scored on a scale from 0 (none) to 4 (very severe), together with the percentage of the area affected, rated on a scale from 0 (no involvement) to 6 (90% to 100% involvement). PASI scoring is performed at four body areas, the head, arms, trunk, and legs. The total PASI score ranges from 0 to 72. The higher the total score, the more severe the disease.

Participants who entered the escape arm or had missing data at week 12 were considered non-responders.

Intent-to-treat population

The sPGA is a static measurement based on induration, erythema, and scaling. The sPGA is assessed on a scale from 0 to 5:

0 = clear (no evidence of plaque elevation, erythema or scaling)

1. = almost clear (minimal plaque elevation, erythema or scaling)
2. = mild (mild plaque elevation or scaling, light red coloration)
3. = moderate (moderate plaque elevation, scaling, light red coloration)
4. = marked (marked plaque elevation, thick, non-tenacious scale predominates, bright red coloration)
5. = severe (severe plaque elevation, very thick tenacious scaling, dusky to deep red coloration).

Participants who entered the escape arm or had missing data at week 12 were considered non-responders.

Intent-to-treat population

The Children's Dermatology Life Quality Index (CDLQI) was used to assess the impact of psoriasis on subject health-related quality of life. The CDLQI has 10 items assessing health-related quality of life (HRQOL) in patients with skin disease each measured on a scale from 0 (Not at all) to 3 (Very much). The total score ranges from 0 to 30, with lower scores indicating better quality of life. If participants were ≥ 13 years old, the text instrument was completed by the participants themselves. Participants ≥ 8 but < 13 years old used the cartoon version of the instrument and participants ≤ 7 years old used the cartoon version of the instrument completed with help from the parents or caregivers.

Percent improvement from baseline = (Baseline Value - Post-baseline Value) / Baseline Value * 100.

Participants who entered the escape arm or who had missing data at week 12 were considered to have 0% improvement from baseline.

Intent-to-treat population with available CDLQI data at baseline

The percentage of participants who achieved 90% or greater improvement from baseline in PASI score after 12 weeks of treatment. The PASI score is a combination of the intensity of psoriasis, assessed by erythema (reddening), induration (plaque thickness) and desquamation (scaling) scored on a scale from 0 (none) to 4 (very severe), together with the percentage of the area affected, rated on a scale from 0 (no involvement) to 6 (90% to 100% involvement). PASI scoring is performed at four body areas, the head, arms, trunk, and legs. The total PASI score ranges from 0 to 72. The higher the total score, the more severe the disease.

Participants who entered the escape arm or had missing data at week 12 were considered non-responders.

Intent-to-treat population

The severity assessment for adverse events and infections was done using the Common Toxicity Criteria (CTC) Version 2.0, where Grade 0 = no toxicity, Grade 1 = mild toxicity, Grade 2 = moderate toxicity, Grade 3 = severe toxicity, Grade 4 = life-threatening toxicity.

Serious adverse events were any events that suggested a significant hazard or side effect, regardless of the investigator's or sponsor's opinion on the relationship to study medication. These included, but were not limited to, events at any dose that were fatal, life threatening, required in-patient hospitalization or prolonged hospitalization, were a persistent or significant disability/incapacity, or were a congenital abnormality/birth defect. Medical events that jeopardized a participant, required intervention to prevent one of the above outcomes, or resulted in urgent investigation could be considered serious.

The safety population included all participants who received at least 1 dose of study drug.

Serum concentrations for etanercept were measured by using a validated enzyme-linked immunosorbent assay (ELISA). The lower limit of quantification (LLOQ) was 0.627 ng/mL.

Participants assigned to etanercept at any time during the study, with available data.

Week 12 excludes participants assigned to placebo who escaped to etanercept. Week 48 includes participants randomized to etanercept at week 36 and remaining on etanercept to week 48. Participants randomized to placebo and retreated with etanercept are excluded.

Participants received 0.8 mg/kg etanercept administered by subcutaneous injection once a week (QW) during the 12-week, double-blind, placebo-controlled treatment period (day 1 to week 12).

Participants with a > 50% worsening (ie, increase) in PASI score at or after week 4 compared with baseline and an increase of at least 4 points at 1 visit, or with an increase of more than 25% and by a minimum of 4 points at each of two consecutive visits, escaped to etanercept 0.8 mg/kg once a week up to week 12.

Participants received open-label etanercept 0.8 mg/kg once a week during the 24-week, open-label treatment period (weeks 13 to 36).

Participants who did not achieve PASI 50 at week 24 or PASI 75 at week 36 continued to receive open-label etanercept 0.8 mg/kg QW plus optional topical standard-of-care therapy (low-to-moderate-potency topical corticosteroids) until week 48.

At week 36, participants with a PASI 75 response were re-randomized to receive placebo once a week for 12 weeks in the double-blind, withdrawal period (weeks 37 to 48) or until relapse (loss of PASI 75 response).

At week 36, participants with a PASI 75 response were re-randomized to receive 0.8 mg/kg etanercept once a week for 12-weeks in the double-blind, withdrawal period (weeks 37 to 48) or until relapse (loss of PASI 75 response).

Participants randomized to placebo at week 36 who relapsed (loss of PASI 75 response) resumed open-label treatment with 0.8 mg/kg etanercept once a week until week 48.

Participants randomized to etanercept at week 36 who relapsed (loss of PASI 75 response) resumed open-label treatment with 0.8 mg/kg etanercept once a week until week 48.