A Study to Evaluate the Efficacy, Safety, and Pharmacokinetics of Subcutaneously Administered Guselkumab for the Treatment of Chronic Plaque Psoriasis in Pediatric Participants

Inclusion Criteria:

   - Have a diagnosis of chronic plaque-type psoriasis for at least 6 months (with or
   without psoriatic arthritis [PsA]), prior to first administration of study
   intervention, defined as having at screening and baseline, Investigator Global
   Assessment (IGA) greater than or equal to (>=) 3, Psoriasis Area and Severity Index
   (PASI) >=12, >=10% body surface area (BSA) involvement and at least one of the
   following: very thick lesions, clinically relevant facial, genital, or hand/ foot
   involvement, PASI>=20, >20% BSA involvement, or IGA=4

   - Be a candidate for phototherapy or systemic treatment of plaque psoriasis (either
   naive or history of previous treatment)

   - Have plaque psoriasis considered by the investigator as inadequately controlled with
   phototherapy and/or topical therapy after an adequate dose and duration of therapy

   - Be considered, in the opinion of the investigator, a suitable candidate for etanercept
   therapy, according to their country's approved Enbrel product labeling

   - Be otherwise healthy on the basis of physical examination, medical history, and vital
   signs performed at screening. Any abnormalities, must be consistent with the
   underlying illness in the study population and this determination must be recorded in
   the participant's source documents and initialed by the investigator

   - Must have acceptable evidence of immunity to varicella and measles, mumps, and rubella
   (MMR), which includes any one of the following: documentation of age-appropriate
   vaccination that includes both doses of each vaccine (unless local guidelines specify
   otherwise) or documentation of past infection by a healthcare provider or in the
   absence of previous 2 criteria, participants must have positive protective antibody
   titers to these infection prior to the first administration of study intervention. For
   participants who have not completed the recommended vaccination schedule for varicella
   and MMR, and the subsequent vaccination falls within the next 4 years, an accelerated
   vaccination schedule must be completed prior to study enrollment if available and
   required or strongly recommended for the location. If varicella or MMR vaccines are
   utilized, it is necessary for 2 weeks to elapse between the vaccination and receipt of
   study intervention

Exclusion Criteria:

   - Currently has nonplaque forms of psoriasis (example, erythrodermic, guttate, or
   pustular)

   - Has current drug-induced psoriasis (example, a new onset of psoriasis or an
   exacerbation of psoriasis from beta blockers, calcium channel blockers, or lithium)

   - Has previously received guselkumab or etanercept

   - Has a history of chronic or recurrent infectious disease, including but not limited to
   chronic renal infection, chronic chest infection (example, bronchiectasis), recurrent
   urinary tract infection (recurrent pyelonephritis or chronic non-remitting cystitis),
   fungal infection (mucocutaneous candidiasis), or open, draining, or infected skin
   wounds or ulcers

   - Has a known history of lymphoproliferative disease, including lymphoma; a history of
   monoclonal gammopathy of undetermined significance (MGUS); or signs and symptoms
   suggestive of possible lymphoproliferative disease, such as lymphadenopathy or
   splenomegaly