Adverse events

In short term phase (Week 0-6), participants weighing greater than or equal to (\>=) 45 kilograms (kg), received fixed subcutaneous induction doses of golimumab 200 milligrams (mg) at Week 0 and 100 mg at Week 2. Participants weighing less than (\<) 45 kg received body surface area (BSA) adjusted doses with 120 milligrams per square meter (mg/m\^2) (up to a maximum of 200 mg) at Week 0 and 60 mg/m\^2 (up to a maximum of 100 mg) at Week 2. In long-term Phase (Week 6 through Week 54), participants who showed a clinical response at Week 6 continued receiving subcutaneous golimumab 100 mg or 60 mg/m\^2 every 4 weeks (q4w) through Week 50. Participants with no clinical response (non-responders) at Week 6 received additional golimumab doses at Weeks 6 and 10 at the discretion of the investigator. Participants who showed partial Mayo response at Week 14, continued golimumab 100 mg or 60 mg/m\^2 qw4 through Week 50. Participants without a partial Mayo response at Week 14 were withdrawn from further treatment and entered a 16-week safety follow-up period after the last dose. In study extension (Week 54 to end of study) phase, participants who were benefited from golimumab, at the discretion of the investigator, continued to receive SC golimumab q4w until marketing authorization is obtained for golimumab or participant turns 18 years had access to commercially available golimumab or decided by the sponsor.

In short term phase (Week 0-6), participants weighing \>=30 kg, received infliximab 5 mg/kg intravenous (IV) infusion at Week 0 and Week 2. In long-term Phase (Week 6 through Week 54), participants who showed a clinical response at Week 6 continued to receive infliximab 5 mg/kg IV infusion every 8 weeks (q8w) through Week 46. Participants who did not show a clinical response at Week 6 received an increased dose of infliximab that is 10 mg/kg (capped at 1 gram) starting at Week 6 and every q8q thereafter, or 5 mg/kg at Week 6 and Week 8 followed by 10 mg/kg (capped at 1 gram) at Week 14 and every q8w thereafter. Participants who showed a partial Mayo responders at Week 14 continued infliximab 10 mg/kg every 8 weeks through Week 46. Participants who did not show partial Mayo response at Week 14 either received a further dose escalation to 10 mg/kg q4w (capped at 1 gram) or were withdrawn from the study. At Week 22, participants who received the escalated dose of infliximab 10 mg/kg q4w were required to show a partial Mayo response and who met this criterion continued to receive open-label infliximab 10 mg/kg (capped at 1 gram) q4w through Week 50. After Week 54 evaluations, participants receiving infliximab were withdrawn from study participation and transitioned to local standard of care.