Phase II Efficacy Study Looking at a Single-dose of One of Three Dose Levels of AIN457 in Patients With Chronic Plaque-type Psoriasis

Inclusion Criteria: * Diagnosis of plaque psoriasis for at least 6 months prior to screening. The patients must meet all of the following criterion: 1. Coverage of the body surface area (BSA) of 10% or more with plaques 2. A score of 3 or more on the IGA (Investigator Global Assessment) scale 3. A PASI score of at least 12 at baseline; Exclusion Criteria: * Have forms of psoriasis other than the required "plaque psoriasis" * Women of childbearing potential * Recent use of investigational drugs or treatment with other biological therapies (wash-out periods required) * Previous treatment with this investigational drug * Subjects with active or history of clinically significant cardiac, kidney or liver abnormalities Other protocol-defined inclusion/exclusion criteria may have applied.