Safety of Tofacitinib in the Treatment of Rheumatoid Arthritis in Latin America Compared With the Rest of the World Population

Objective: Rheumatoid arthritis (RA) is a chronic, autoimmune disease characterized by joint destruction. Tofacitinib is an oral Janus kinase inhibitor for the treatment of RA. This post hoc analysis assessed the safety of tofacitinib in Latin American (LA) patients with RA versus the Rest of World (RoW) population. Methods: Data were pooled from 14 clinical studies of tofacitinib: six Phase 2, six Phase 3 and two long-term extension studies. Incidence rates (IRs; patients with events/100 patient-years of treatment exposure) were calculated for safety events of special interest combined across tofacitinib doses. 95% confidence intervals (CI) for IRs were calculated using the maximum likelihood method. Descriptive comparisons were made between LA and RoW (excluding LA) populations. Results: This analysis included data from 984 LA patients and 4687 RoW patients. IRs for safety events of special interest were generally similar between LA and RoW populations, with overlapping 95% CIs. IRs for discontinuation due to adverse events, serious infections, tuberculosis, all herpes zoster (HZ), serious HZ, malignancies (excluding non-melanoma skin cancer) and major adverse cardiovascular events were numerically lower for LA versus RoW patients; IR for mortality was numerically higher. No lymphoma was reported in the LA population versus eight cases in the RoW population. Exposure (extent and length) was lower in the LA population (2148.33 patient-years [mean = 2.18 years]) versus RoW (10515.68 patient-years [mean = 2.24 years]). Conclusion: This analysis of pooled data from clinical studies of tofacitinib in patients with RA demonstrates that tofacitinib has a consistent safety profile across LA and RoW patient populations.