Cutaneous adverse events during treatment of chronic inflammatory rheumatic conditions with tumor necrosis factor antagonists: study using the Spanish registry of adverse events of biological therapies in rheumatic diseases.

OBJECTIVE: To analyze the incidence rate (IR) and risk factors of cutaneous adverse events (CAE) in patients with chronic inflammatory rheumatic diseases treated with tumor necrosis factor (TNF) antagonists.
METHODS: We analyzed all patients from the BIOBADASER (Base de Datos de Productos Biológicos de la Sociedad Española de Reumatología) registry treated with a TNF antagonist (infliximab, etanercept, or adalimumab). Data collected included age, sex, diagnosis and duration of rheumatic disease, type of TNF antagonist, and concomitant treatment. Type of CAE was classified as local or systemic cutaneous manifestation related to treatment administration (infusion reaction), infection, malignancy, or autoimmune skin disease. Time of onset of CAE and outcome were also recorded. The IRs of CAE per 1,000 patient-years of exposure with 95% confidence intervals (95% CIs) were estimated. Multivariable analysis was performed to identify potential risk factors for CAE.
RESULTS: A total of 5,437 patients were included, representing 17,330 patient-years of exposure. A total of 920 CAE were reported; the IRs per 1,000 patient-years were 53 (95% CI 50-57) for CAE, 28 (95% CI 25-30) for infection, 15 (95% CI 13-17) for infusion reactions, 5 (95% CI 4-6) for autoimmune skin diseases, and 3 (95% CI 2-4) for skin malignancy. The mean time between starting TNF antagonist treatment and CAE was 1.78 years. In 32% of patients, CAE required TNF antagonist withdrawal. The main risk factors for CAE were female sex and treatment with infliximab, leflunomide, and glucocorticoids.
CONCLUSION: The IR of CAE in patients treated with TNF antagonists is significant and should be addressed carefully, and withdrawal of therapy is required in some cases.