This was a multicenter, randomized, double-blind, placebo- and active-controlled (etanercept in single blinded arm) study in pediatric subjects aged 6 years to less than 18 years with severe chronic plaque psoriasis. Approximately 160 subjects aged 6 years to \<18 years were enrolled, of which at least 30 were 6 years to \<12 years old. Subjects were enrolled at approximately 70 study sites worldwide.

The purpose of this study was to demonstrate superior efficacy of secukinumab versus placebo at Week 12, based on both PASI 75 and IGA mod 2011 0 or 1 response rates in children and adolescents aged 6 to less than 18 years with severe chronic plaque psoriasis who had inadequate control of symptoms with topical treatment, or failed to respond to or tolerate previous systemic treatment and/or UV therapy The study assessed the long term safety and tolerability of secukinumab in this pediatric age group and described the efficacy and safety of secukinumab compared to etanercept. This study provided efficacy and safety data to support the extension of label of secukinumab to include children and adolescents (6 years to \<18 years) with severe chronic plaque psoriasis Two age subgroups were studied in a staggered approach within this clinical study: 12 to less than 18 years of age, and 6 to less than 12 years of age . Enrolment of children aged 6 to less than 12 years began after a favorable recommendation by an independent external Data Monitoring Committee (DMC) who reviewed data of approximately 80 adolescents. Adolescents continued to be recruited while the data from the first 80 subjects was being collected and analyzed Subjects were randomized using a 1:1:1:1 ratio into one of the treatment arms: secukinumab low dose, secukinumab high dose, etanercept or placebo. Subjects randomized to secukinumab treatment arms (high dose and low dose) received dose based on the weight category (\<25 kg, 25 to \<50kg, ≥50 kg). The study consisted of 5 periods: screening (up to 4 weeks), induction (of 12 weeks), maintenance (of 40 weeks), extension treatment epoch (open-label of 184 weeks) and post- treatment follow-up epoch (of 16 weeks). The screening period of up to 4 weeks was used to assess eligibility of the patients and to taper patients off prohibited medications. The Induction period is defined as randomization through Week 12. In this period, the study was both active and placebo-controlled and at its completion, the primary endpoint was assessed (Week 12). The Maintenance period is defined as Week 12 (from dosing) through Week 52. During this period, the study was active-controlled, and the objectives focused on the maintenance of the response observed at Week 12. Patients who received secukinumab or etanercept during induction continued in maintenance with the same treatment. Patients who were on placebo during induction and at Week 12 were PASI 75 non-responders were switched to either secukinumab low dose or secukinumab high dose treatment group in the Maintenance period according to their baseline randomization. At the end of the Maintenance period, all patients on secukinumab entered the Extension treatment period and continued to receive the same dose of secukinumab. The Extension treatment period was defined as Week 52 (from dosing) until Week 236. In this period, all patients were treated with secukinumab, and the purpose was the collection of long-term safety and efficacy data. Patients who participated in the Maintenance period but prematurely discontinued the study were not able to enter the Extension treatment period. Patients receiving etanercept were not eligible to enter the Extension treatment period. Instead, at Week 52, they completed an EOM visit and then entered the post-treatment Follow-up period.