Introduction: Upadacitinib is a Janus kinase inhibitor under investigation in patients with psoriatic arthritis (PsA). This study assessed the 56-week efficacy and safety of upadacitinib in patients with PsA and an inadequate response or intolerance to biologic therapy.
Methods: In the phase 3 SELECT-PsA 2 study, patients were randomized to 56 weeks of blinded treatment with oral upadacitinib 15 or 30 mg once daily, or placebo switched to upadacitinib 15 or 30 mg once daily at week 24. Efficacy endpoints included the proportion of patients achieving 20/50/70% improvement in American College of Rheumatology criteria (ACR20/50/70), 75/90/100% improvement in Psoriasis Area and Severity Index (PASI75/90/100), and minimal disease activity. Safety was assessed throughout the study.
Results: Of 641 patients who received ≥ 1 dose of study drug, 479 (74.7%) completed 56 weeks of treatment. Improvements in the proportion of patients achieving ACR20/50/70, PASI75/90/100, and minimal disease activity were maintained with both doses of upadacitinib through 56 weeks. Week 56 results for patients who switched from placebo to upadacitinib at week 24 were similar to those for patients originally randomized to the upadacitinib groups. The exposure-adjusted event rate for serious infections was 2.6 and 6.1 events/100 patient-years in the upadacitinib 15 and 30 mg groups, respectively. Herpes zoster occurred more frequently with upadacitinib 30 versus 15 mg; most cases were non-serious.
Conclusion: In patients with PsA who had an inadequate response or intolerance to biologic therapy, the efficacy of upadacitinib was maintained over 56 weeks with no new significant safety signals observed.
Trial registration: NCT03104374.
Keywords: Janus kinase inhibitors; Psoriatic arthritis; Upadacitinib.