Efficacy of Tofacitinib for the Treatment of Psoriatic Arthritis: Pooled Analysis of Two Phase 3 Studies

Introduction Tofacitinib is an oral Janus kinase inhibitor for the treatment of psoriatic arthritis (PsA). This post hoc analysis assessed the efficacy of tofacitinib using pooled data from two phase 3 studies of patients with active PsA. Methods Data were pooled from OPAL Broaden (NCT01877668) and OPAL Beyond (NCT01882439). Patients had active PsA and either an inadequate response (IR) to ≥ 1 conventional synthetic disease-modifying antirheumatic drug (csDMARD) and were tumor necrosis factor inhibitor (TNFi)-naïve (OPAL Broaden), or had IR to ≥ 1 TNFi (OPAL Beyond). Pooled data included tofacitinib 5 or 10 mg twice daily (BID; to month 6) and placebo (to month 3; patients then switched to tofacitinib 5 or 10 mg BID). Patients also received one background csDMARD. Endpoints included American College of Rheumatology (ACR)20 response and change from baseline in Health Assessment Questionnaire-Disability Index (HAQ-DI) at month 3 (primary endpoints), ACR50/70 response, HAQ-DI response (decrease from baseline ≥ 0.35) and improvements in painful and swollen joint counts, psoriasis, enthesitis and dactylitis to month 6. Results A total of 710 patients were included (tofacitinib 5 mg BID: 238; tofacitinib 10 mg BID: 236; placebo: 236). Primary endpoints showed significant improvements at month 3 in patients receiving tofacitinib 5 or 10 mg BID vs. placebo. Significant improvements in HAQ-DI response, painful and swollen joints, psoriasis, enthesitis and dactylitis vs. placebo were observed for both tofacitinib doses at month 3. Efficacy was maintained to month 6 (final pooled time point). Conclusions In a pooled analysis of csDMARD-IR/TNFi-naïve and TNFi-IR patients, tofacitinib was superior to placebo at month 3 across four PsA domains: peripheral arthritis, psoriasis, enthesitis and dactylitis. Trial Registration OPAL Broaden (NCT01877668); OPAL Beyond (NCT01882439). Funding Pfizer Inc.