Efficacy and Safety of Risankizumab for Active Psoriatic Arthritis: 100-Week Results from the Phase 3 KEEPsAKE 1 Randomized Clinical Trial

Introduction: Patients with psoriatic arthritis (PsA) require treatment providing durable long-term efficacy in different disease domains as well as safety. We present 100-week efficacy and safety results of risankizumab in patients with active PsA and previous inadequate response/intolerance to ≥ 1 conventional synthetic disease-modifying antirheumatic drug (csDMARD-IR). Methods: KEEPsAKE 1 (NCT03675308) is a global phase 3 study, including a 24-week, double-blind, placebo-controlled and ongoing open-label extension periods. Patients were randomized 1:1 to receive risankizumab 150 mg or placebo at baseline and weeks 4 and 16. After week 24, all patients received open-label risankizumab every 12 weeks thereafter. Patients were evaluated through 100 weeks. Endpoints included achieving ≥ 20% reduction in American College of Rheumatology criteria for symptoms of rheumatoid arthritis (ACR20), minimal disease activity (MDA; defined as ≥ 5/7 criteria of low disease activity and extent), and other measures. Results: Overall, 828/964 (85.9%) patients completed week 100. For patients receiving continuous risankizumab, 57.3%, 70.6%, and 64.3% achieved ACR20 at weeks 24, 52, and 100, respectively. For the placebo/risankizumab cohort, 33.5% achieved ACR20 at week 24 but increased after switching to active treatment at weeks 52 (63.7%) and 100 (62.1%). In ACR20 responders at week 52, 81.2% of both treatment cohorts maintained response at week 100. MDA was achieved by 25.0%, 38.3%, and 38.2% of the continuous risankizumab cohort at weeks 24, 52, and 100. In the placebo/risankizumab cohort, 10.2% achieved MDA at week 24, increasing at weeks 52 (28.0%) and 100 (35.2%). MDA response was maintained at week 100 in week 52 responders in the continuous risankizumab (75.5%) and placebo/risankizumab cohorts (78.2%). Similar trends were observed for other efficacy measures. Risankizumab was generally well tolerated through 100 weeks. Conclusions: For patients with active PsA who are csDMARD-IR, risankizumab demonstrated durable long-term efficacy and was generally well tolerated, with a consistent long-term safety profile. Trial Registration: ClinicalTrials.gov identifier, NCT03675308.