Effectiveness and Feasibility Associated with Switching to a Second or Third TNF Inhibitor in Patients with Psoriatic Arthritis: A Cohort Study from Southern Sweden

Objective. Because new modes of action for the treatment of psoriatic arthritis (PsA) are emerging, it is important to understand the use of switching to a second or third antitumor necrosis factor (anti-TNF) agent. This study investigated drug survival and treatment response rates of patients with PsA undergoing second- and third-line anti-TNF therapy.

Methods. Patients with PsA were monitored in a prospective, observational study. Patients who switched anti-TNF therapy once (first-time switchers, n = 217) or twice (second-time switchers, n = 57) between January 2003 and March 2012 were studied. American College of Rheumatology (ACR) and European League Against Rheumatism (EULAR) good response at 3 and 6 months, as well as drug survival, were reported and further analyzed using the Cox and logistic regression models.

Results. Median age for first-time switchers was 47 years and 42% were men. The corresponding values for second-time switchers were 48 years and 40% men. Three-month ACR20 Lund Efficacy Index (LUNDEX) response was achieved by 47% of first-time and 22% of second-time switchers; ACR50 LUNDEX rates were 21% and 14%, ACR70 LUNDEX rates were 12% and 2%, and EULAR good LUNDEX rates were 26% and 10%, respectively. Median drug survival time for patients switching anti-TNF for the first time was 64 months (95% CI 31–97) compared with 14 months (95% CI 5–23) for second-time switchers. Identified baseline predictor of ACR20 response to second-line treatment was the 28-joint Disease Activity Score values at baseline (OR 1.45, 95% CI 1.01–2.10), while higher Health Assessment Questionnaire scores predicted premature drug withdrawal (HR 1.60, 95% CI 1.03–2.48).

Conclusion. Response rates of first-time anti-TNF switchers are moderate, while the inferior response rates of second-time switchers suggest other therapeutic options should be considered in this situation.