Must be 6 to less than 18 years of age at the time of randomization
Plaque-type psoriasis history for at least 3 months.
Severe plaque-type psoriasis meeting all of the following three criteria:
PASI score of 20 or greater,
Investigator's Global Assessment (IGA) score of 4
Total body surface area (BSA) affected of 10% or greater.
Patient being regarded by the investigator to be a candidate for systemic therapy because of:
inadequate control of symptoms with topical treatment, or
failure to respond to or tolerate previous systemic treatment and/or UV therapy
Current forms of psoriasis other than chronic plaque-type psoriasis (for example, pustular, erythrodermic, guttate) at randomization.
Current drug-induced psoriasis.
Previous use of secukinumab or any drug that targets IL-17 or IL-17 receptor.
Underlying condition (including, but not limited to metabolic, hematologic, renal, hepatic, pulmonary, neurologic, endocrine, cardiac, infectious or gastrointestinal) which in the opinion of the investigator significantly immunocompromises the subject and/or places the subject at unacceptable risk for receiving an immunomodulatory therapy
History of an ongoing, chronic or recurrent infectious disease, or evidence of untreated tuberculosis.
History of lymphoproliferative disease or history of malignancy of any organ system within the past 5 years.
Pregnant or nursing (lactating) women.
Other protocol-defined inclusion/exclusion criteria may apply.