A Study to Evaluate the Efficacy, Safety, and Drug Concentration of Certolizumab Pegol (CZP) in Children and Adolescent Study Participants With Moderate to Severe Chronic Plaque Psoriasis (PSO)

Inclusion Criteria:

Study participant must have a diagnosis of moderate to severe plaque psoriasis (PSO) for ≥3 months and:

Body Surface Area (BSA) affected by psoriasis ≥10 %
Physician's Global Assessment (PGA) score ≥3 (on a scale from 0 to 4)
Psoriasis Area and Severity Index (PASI) score is ≥12 or

PASI score is ≥10 and <12 with at least one of the following:

Clinically relevant facial or scalp involvement
Clinically relevant genital involvement
Clinically relevant palm and sole involvement
Clinically relevant axillary involvement Study participants aged ≥12 years may alternatively have a diagnosis of moderate to severe mixed guttate/plaque PSO with >50 % to <80 % guttate lesions for ≥3 months, and must meet the same criteria listed above
Study participant must be a candidate for systemic psoriasis therapy and/or phototherapy and/or photochemotherapy

Exclusion Criteria:

Study participant previously participated in this study or has previously been treated with certolizumab pegol (CZP)
Study participant has generalized pustular or erythrodermic psoriasis (PSO)
Study participant has guttate PSO without plaque PSO
Study participant has had a primary failure to an anti-tumor necrosis factor agent
Study participant has had prior exposure to >2 biologic therapies
Study participant has a history of severe major depression or suicide attempt (including an actual attempt, interrupted attempt, or aborted attempt), or has had suicidal ideation in the past 6 months as indicated by a positive response ("Yes") to either Question 4 or Question 5 of the "Screening/Baseline" version of the Columbia Suicide Severity Rating Scale (CSSRS) at Screening