The purpose of the study is to evaluate the pharmacokinetic (PK) of certolizumab pegol (CZP) in study participants aged 6 to 17 years with moderate to severe chronic plaque psoriasis (PSO) in order to support extrapolation of efficacy.

Inclusion Criteria:

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

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

Data from this trial may be requested by qualified researchers six months after product approval in the US and/or Europe, or global development is discontinued, and 18 months after trial completion. Investigators may request access to anonymized individual patient-level data and redacted trial documents which may include: analysis-ready datasets, study protocol, annotated case report form, statistical analysis plan, dataset specifications, and clinical study report. Prior to use of the data, proposals need to be approved by an independent review panel at www.Vivli.org and a signed data sharing agreement will need to be executed. All documents are available in English only, for a prespecified time, typically 12 months, on a password protected portal. This plan may change if the risk of re-identifying trial participants is determined to be too high after the trial is completed; in this case and to protect participants, individual patient-level data would not be made available.

Data from this trial may be requested by qualified researchers six months after product approval in the US and/or Europe or global development is discontinued, and 18 months after trial completion.

Qualified researchers may request access to anonymized IPD and redacted study documents which may include: raw datasets, analysis-ready datasets, study protocol, blank case report form, annotated case report form, statistical analysis plan, dataset specifications, and clinical study report. Prior to use of the data, proposals need to be approved by an independent review panel at www.Vivli.org and a signed data sharing agreement will need to be executed. All documents are available in English only, for a pre-specified time, typically 12 months, on a password protected portal.