The purpose of this study is to demonstrate efficacy including effect on inhibition of progression of structural damage, safety and tolerability up to 2 years with primary focus at Week 16 (week 24 for structural damage), to support the use of secukinumab pre-filled syringe (PFS) by subcutaneous (s.c.) self-administration with or without loading regimen in subjects with active Psoriatic Arthritis (PsA) despite current or previous NSAID, DMARD therapy and/or previous anti-TNFα therapy. Long term efficacy up to 2 years will be based on signs and symptoms of joint/bone structure preservation (X-ray) and improvement in physical function measured by Health Assessment Questionnaire - Disability Index (HAQ-DI©), as well as skin and nail improvement for psoriasis signs.