A Safety Study of Ustekinumab in the Treatment of Pediatric Participants Aged 6 Years and Older With Moderate to Severe Plaque Psoriasis

An adverse event is any untoward medical occurrence in a patient administered a medicinal product. An adverse event does not necessarily have a causal relationship with the treatment. An adverse event can be any unfavorable and unintended sign, symptom, or disease temporally associated with the use of a medicinal product, whether or not related to that medicinal product.

All participants will be monitored for the long-term safety of ustekinumab for the frequency and severity of adverse events potentially related to immune modulation and of clinical interest such as: serious infections, malignancies, and autoimmunity.

Growth will be based on height recorded at baseline and throughout the observational period.

Growth will be based on body weight recorded at baseline and throughout the observational period.

Growth will be based on body weight recorded at baseline and throughout the observational period. Sex and age adjusted BMI will be calculated by dividing the body weight (in kilograms) by the square of height (in meters).

The Tanner scale is used to measure visible changes during puberty commonly referred to as "Tanner stages". It has 3 components: breasts/genitalia, pubic hair, and growth. Female participants are evaluated for breast development and pubic hair distribution and male participants are evaluated for development of external genitalia and pubic hair distribution, based on a 5-stage ordinal scale ranging from TS 1 (prepubertal/preadolescent characteristics) to TS 5 (mature or adult characteristics).

The PASI is a measure for assessing and grading the severity and extent of psoriatic lesions and their response to therapy. The PASI measure also accounts for body surface area of psoriasis involvement. In the PASI measure, the body is divided into 4 regions: the head, trunk, upper extremities, and lower extremities. Each of these areas is assessed separately for erythema, induration and scaling, which are each rated on a scale of 0 to 4. Total PASI score ranges from 0 to 72. A PASI 50 response represents at least 50 percent improvement from baseline in the PASI score.

The PASI is a measure for assessing and grading the severity and extent of psoriatic lesions and their response to therapy. The PASI measure also accounts for body surface area of psoriasis involvement. In the PASI measure, the body is divided into 4 regions: the head, trunk, upper extremities, and lower extremities. Each of these areas is assessed separately for erythema, induration and scaling, which are each rated on a scale of 0 to 4. Total PASI score ranges from 0 to 72. A PASI 75 response represents at least 75 percent improvement from baseline in the PASI score.

The PASI is a measure for assessing and grading the severity and extent of psoriatic lesions and their response to therapy. The PASI measure also accounts for body surface area of psoriasis involvement. In the PASI measure, the body is divided into 4 regions: the head, trunk, upper extremities, and lower extremities. Each of these areas is assessed separately for erythema, induration and scaling, which are each rated on a scale of 0 to 4. Total PASI score ranges from 0 to 72. A PASI 90 response represents at least 90 percent improvement from baseline in the PASI score.

The PGA documents the physician's assessment of the severity of the participant's psoriasis lesions at a given time on a 5-point scale, where (0) = cleared, (1) = minimal, (2) = mild, (3) = moderate, (4) = marked, and (5) = severe. Overall lesions are graded for induration, erythema, and scaling. The sum of the 3 scores will be divided by 3 to obtain a final PGA score. Higher scores indicate greater severity of disease.

Percentage of participant's body surface area covered by plaque-type psoriasis was estimated using the palm method: the area equivalent to the participant's palm extending to the proximal interphalangeal joints and thumb = 1 percent (%) of BSA. The total BSA affected was the summation of the BSA of the individual regions affected.

The Children's Dermatology Quality Life Index (CDLQI) questionnaire is used to assess the participant's perspective on the impact of skin disorders on daily living. It is a 10 item instrument with 4-item response options on a scale from 0 (Not at all) to 3 (Very much) and a recall period of 1 week. The total score ranges from 0 to 30, with lower scores indicating better quality of life.

Participants are assessed for pre-existing and new comorbidities associated with pediatric plaque psoriasis.