Conditions: Arthritis, Psoriatic
Keywords: Arthritis, Psoriatic Ustekinumab CNTO 1275 Stelara Psoriasis
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 615
Healthy volunteers: no

Brief summary:
The purpose of this study is to evaluate the effectiveness (improvement of signs and symptoms) and safety of ustekinumab in participants with active psoriatic arthritis.

Detailed description:
This is a randomized (participants are assigned different treatments based on chance), double-blind (neither the participant nor the physician knows whether drug or placebo is being taken, or at what dosage), parallel-group (each group of participants will be treated at the same time), and multicenter (study conducted at multiple sites) study. Approximately, 615 participants will participate in this study. Participants will be assigned to one of three treatment groups: Group I: ustekinumab 45 mg, Group II: ustekinumab 90 mg, and Group III: placebo group (an inactive substance). Participants will receive either 45 mg ustekinumab or 90 mg ustekinumab at Weeks 0, 4, and every 12 weeks until Week 88 as randomized to respective groups. Participants in placebo group will receive placebo at Weeks 0, 4, 16, and 20 and 45 mg ustekinumab at Weeks 24 and 28 followed by every 12 weeks dosing until Week 88. Participants who do not have greater than or equal to 5 percentage improvement in their disease (tender and swollen joints) will be eligible for an early escape. Specifically, during early escape at Week 16, participants in Group I will receive 90 mg ustekinumab, for participants in Group II same dosing schedule will be continued, and participants in placebo group will receive 45 mg ustekinumab. Safety evaluations will include assessments of adverse events, clinical laboratory tests, and physical examination. The maximum study duration will be approximately 108 weeks.

Arms:
arm 1: Participants will receive subcutaneous (SC) injections of placebo at Weeks 0, 4, 16, and 20. At Week 24 participants will cross over to receive SC injections of ustekinumab 45 mg at Weeks 24 and 28 and every 12 weeks thereafter with the last dose at Week 88. If early escape, SC injections of 45 mg ustekinumab will be given at Weeks 16, 20, and 28 and every 12 weeks thereafter with the last dose at Week 88. For participants entering early escape, a SC placebo injection will be given at Week 24 to maintain the blind. arm 2: Participants will receive SC injections of ustekinumab 45 mg at Weeks 0 and 4 and every 12 weeks thereafter with the last dose at Week 88. If early escape, SC injections of 90 mg ustekinumab will be given at Week 16 and every 12 weeks thereafter with the last dose at Week 88. Participants will receive SC injections of placebo at Weeks 20 and 24 to maintain the blind. arm 3: Participants will receive SC injections of ustekinumab 90 mg at Weeks 0 and 4 and every 12 weeks thereafter with the last dose at Week 88. If early escape, the same dosage schedule will continue. Participants will receive SC injections of placebo at Weeks 20 and 24 to maintain the blind.

Interventions: intervention 1: Placebo intervention 2: Ustekinumab 45 mg intervention 3: Ustekinumab 90 mg
Intervention descriptions: intervention 1: SC injections intervention 2: SC injections intervention 3: SC injections

Protocol document: