Phase III Study of Efficacy and Safety of Secukinumab Versus Placebo, in Combination With Glucocorticoid Taper Regimen, in Patients With Polymyalgia Rheumatica (PMR)

Inclusion Criteria: * Signed informed consent must be obtained prior to participation in the study * Male or non-pregnant, non-lactating female participants at least 50 years of age. * Diagnosis of PMR according to the provisional American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) classification criteria: Participants ≥ 50 years of age with a history of bilateral shoulder pain accompanied by elevated C-reactive protein (CRP) concentration (≥ 10 mg/L) and/or elevated erythrocyte sedimentation rate (ESR) (≥ 30 mm/hr) who scored at least 4 points from the following optional classification criteria: * Morning stiffness \> 45 minutes (min) (2 points) * Hip pain or restricted range of motion (1 point) * Absence of rheumatoid factor and/or anti-citrullinated protein antibodies (2 points) * Absence of other joint involvement (1 point) * Participants must have a history of being treated for at least 8 consecutive weeks with prednisone ≥ 10 mg/day, or equivalent dose of another GC at any time prior to screening * Participants must have had at least one episode of PMR relapse while attempting to taper prednisone at a dose that is ≥ 5 mg/day (or equivalent dose of another GC) within the past 12 weeks prior to BSL. Diagnosis of a PMR relapse is defined as participant meeting both of the following: * Recurrence of bilateral shoulder girdle and/or bilateral hip girdle pain associated with inflammatory stiffness with or without additional symptoms indicative of PMR relapse (such as constitutional symptoms) within 12 weeks prior to BSL that are in the opinion of the Investigator not due to other diseases that may mimic PMR such as osteoarthritis in shoulders or hips, polyarticular calcium pyrophosphate deposition disease, rotator cuff disease, adhesive capsulitis (frozen shoulder) or fibromyalgia. * Elevated ESR (≥ 30 mm/hr) and/or elevated CRP (\> upper limit of normal (ULN)) attributable to PMR at the time of relapse and/or at screening * Participants must have been treated as per local treatment recommendations following the latest PMR relapse and must be on prednisone of at least 7.5 mg/day (or equivalent) and not exceeding 25 mg/day at screening and during the screening period Exclusion Criteria: * Evidence/history of GCA as indicated by typical (cranial) symptoms (e.g., persistent or recurrent localized headache, temporal artery or scalp tenderness, jaw claudication, blurry or loss of vision, symptoms of stroke), extremity claudication, imaging and/or temporal artery biopsy result * Concurrent rheumatoid arthritis or other inflammatory arthritis or other connective tissue diseases, such as but not limited to systemic lupus erythematosus, systemic sclerosis, vasculitis, myositis, mixed connective tissue disease, and ankylosing spondylitis * Concurrent diagnosis or history of neuropathic muscular diseases or fibromyalgia * Inadequately treated hypothyroidism (e.g., persistence of symptoms, lack of normalization of serum TSH despite regular hormonal replacement treatment) * Previous exposure to secukinumab or other biologic drug directly targeting IL-17 or IL-17 receptor * Participants treated with tocilizumab or other IL-6/IL6-receptor inhibitors within 12 weeks or within 5 half-lives (whichever is longer) prior to BSL; participant who did not respond to or experienced a relapse during treatment are excluded from enrollment into the study Other protocol-defined inclusion/exclusion criteria may apply