A Long-term Extension (LTE) Study of Guselkumab in Pediatric Participants

Inclusion Criteria:

• Must have completed the dosing planned in the primary pediatric guselkumab study

• Must have received benefit from continued guselkumab therapy in the opinion of theinvestigator

• Before enrollment, a participant must be either: (a) Not of childbearing potential,OR (b) Of childbearing potential and not sexually active, practicing abstinence or ahighly effective method of contraception and agrees to remain on a highly effectivemethod while receiving study intervention and until 12 weeks after the last dose -the end of relevant systemic exposure

• Parent(s) (or their legally acceptable representative) must sign an informed consentform (ICF) indicating that he or she understands the purpose of, and proceduresrequired for, the study and is willing to allow the child to participate in thestudy. Assent is required from participants who are capable of understanding thenature of the study, typically those aged 7 years and older, to ensure theirwillingness to participate. An adolescent who provides assent will have theopportunity to sign an adult ICF upon reaching the age of majority, therebyaffirming their understanding of the study's purpose and procedures, as well astheir willingness to participate.

Exclusion Criteria:

• Participant is greater than or equal to (>=) 18 years of age and resides in acountry where 2 years have elapsed post marketing authorization for the respectiveadult indication

• Participant is <18 years of age and resides in a county where 2 years have elapsedpost marketing authorization for the respective pediatric indication

• Are pregnant, nursing, or planning pregnancy or fathering a child

• Have taken any disallowed therapies before the planned first long-term extension (LTE) dose of study intervention

• Employee of the investigator or study site, with direct involvement in the proposedstudy or other studies under the direction of that investigator or study site, aswell as family members of the employees or the investigator

• Any condition for which, in the opinion of the investigator, participation would notbe in the best interest of the participant or that could prevent, limit, or confoundthe protocol-specified assessments