This study is designed as an extension study to the proof-of-concept trial CAIN457A2206 in patients with psoriatic arthritis and aims to provide continuous treatment with AIN457 for patients in the core trial, to obtain safety and tolerability information. The study will address the evaluation of efficacy following doses of 3 mg/kg AIN457 given every 4 weeks over a period initially up to 6 months (Part 1) and based on the risk/benefit balance of AIN457 in psoriatic arthritis a decision will be made as to whether or not to continue dosing for another 6 month period (Part 2).

Inclusion Criteria:

• Patients who participated and completed the core CAIN457A2206 study up to and including the end of the study (EoS) Visit, i.e. Visit 16 (Week 24), were allowed to enter the extension study upon signing informed consent.
• Patients who discontinued the core study due to unsatisfactory therapeutic effect at their Visit 14 (Week 16) or a later visit could enter the extension study within three weeks of completing the study discontinuation visit of the core study, provided that at their discontinuation visit they met the criteria below. Patients who did not enter the extension study within 3 weeks of completing the study discontinuation visit of the core study, were to have an additional baseline visit (Visit 17) and required to meet the criteria below:
• The number of tender joints was the same or more than the core study baseline; or,
• The number of swollen joints was the same or more than the core study baseline; or,
• There was no improvement compared with the core study baseline in at least three of the following five domains: patient global assessment, physician global assessment, patient pain assessment, Health Assessment Questionnaire and CRP

Exclusion Criteria:

• Patients for whom continued treatment with AIN457 is not considered appropriate by the treating physician.
• Patients who were non-compliant or who demonstrated a major protocol deviation in the core CAIN457A2206 study.
• Patients who discontinued from the core CAIN457A2206 study before Visit 14 (Week 16), and patients who completed the core study or discontinued the core study more than 2 weeks before the baseline visit.
• Pregnant or lactating women
• Presence of active infection
• Positive PPD or HIV test in patients where repeated testing was deemed appropriate due to their risk profile

Other protocol-defined inclusion/exclusion criteria may apply

Adverse events were collected from first dose of study treatment until end of study treatment (Week 52), and continued up to Week 64