An Integrated Analysis of the Safety of Tofacitinib in Psoriatic Arthritis across Phase III and Long-Term Extension Studies with Comparison to Real-World Observational Data

Introduction Tofacitinib is an oral Janus kinase inhibitor for the treatment of psoriatic arthritis (PsA). Objective Our objective was to compare the incidence rates (IRs) of adverse events in tofacitinib clinical trials and real-world observational data for alternative treatments. Methods The tofacitinib “dose-comparison cohort” included months 0–12 of two phase III studies (tofacitinib 5 [n = 238] and 10 [n = 236] mg twice daily [BID]); the “all-tofacitinib comparison cohort” (n = 783) included two phase III and one ongoing long-term extension study (data cutoff May 2016). An “observational comparison cohort” (n = 5799) comprised patients initiating a conventional synthetic disease-modifying antirheumatic drug (DMARD), biologic DMARD, or apremilast in the US Truven MarketScan database from 2010 to 2015. IRs for serious infections (SIEs; requiring hospitalization), herpes zoster (HZ), malignancies (excluding non-melanoma skin cancer [NMSC]), NMSC, and major adverse cardiovascular events (MACE) across cohorts were qualitatively compared. Results IRs (patients with events/100 patient-years) for SIEs were similar between the tofacitinib dose-comparison cohort (5 mg BID: 1.3; 10 mg BID: 2.0) and the observational comparison cohort (1.1–7.9; treatment dependent). The tofacitinib dose-comparison cohort had a higher rate of HZ (5 mg BID: 2.0; 10 mg BID: 2.7) than did the observational comparison cohort (0.8–2.0). IRs for NMSC were generally lower in the all-tofacitinib comparison cohort (0.5) than in the observational comparison cohort (0.4–6.0). IRs for MACE, malignancies excluding NMSC, and NMSC were similar between cohorts. Conclusion In patients with PsA, tofacitinib had a safety profile similar to that of other systemic therapies in real-world settings, except for the risk of HZ, a known risk of tofacitinib. Trial Registration ClinicalTrials.gov: NCT01877668; NCT01882439; NCT01976364.