Study to Evaluate the Safety and Efficacy of Secukinumab 300 mg and 150 mg in Adult Patients With Active Psoriatic Arthritis (PsA) After 16 Weeks of Treatment Compared to Placebo

To demonstrate that the efficacy of secukinumab 300 mg at Week 16 was superior to placebo in adult patients with active PsA based on the proportion of patients achieving an American College of Rheumatology 20 (ACR20) response.

Treatment Period 1 was defined as the period from Randomization through Week 16 (prior to the Week 16 dose). At the start of placebo-controlled Treatment Period 1, patients were randomized via Interactive Response Technology (IRT) in a 2:2:1 ratio to 1 of 3 treatment groups. Group 1- Secukinumab 300 mg: secukinumab 300 mg (2 s.c. injections of the 150-mg dose) once weekly for 5 weeks (at Baseline, Weeks 1, 2, 3, and 4), followed by dosing every 4 weeks. Group 2- Secukinumab 150 mg: secukinumab 150 mg (1 s.c. injection of the 150-mg dose and 1 s.c. injection of placebo) once weekly for 5 weeks (at Baseline, Weeks 1, 2, 3, and 4), followed by dosing every 4 weeks. Group 3- Placebo: placebo (2 s.c. injections of 150 mg secukinumab placebo per dose) once per week for 5 weeks (at Baseline, Weeks 1, 2, 3, and 4), followed by dosing every 4 weeks. At each study treatment visit 2 s.c. injections in the form of prefilled syringes (PFS) were administered. This was necessary to maintain the blind, as secukinumab in PFS is available in either 1.0 mL (150 mg) or 2 x 1.0 mL (300 mg). Placebo to secukinumab was also available in 1.0 mL to match the active drug. Rescue medication was not allowed before completion of Week 16 assessments. Treatment Period 2 patients receiving secukinumab 300 mg (Group 1) continued to receive the same dose up to Week 48. At Weeks 16, 28, and 40 patients on secukinumab 150 mg (Group 2) were classified as responders (≥20% improvement from BL in both tender and swollen joint counts) or nonresponders. * At Weeks 16, 28, and 40 patients on secukinumab 150 mg (Group 2) who were responders continued to receive secukinumab 150 mg (1.0 mL) plus placebo (1.0 mL) every 4 weeks until next evaluation of responder status at Weeks 28 or 40. * Patients who did not meet the responder criteria at Week 16, 28, or 40 started receiving secukinumab 300 mg s.c. every 4 weeks and continued this dose up to Week 48. * Patients on placebo (Group 3) regardless of their responder status started receiving secukinumab 300 mg s.c. every 4 weeks from Week 16 up to Week 48.