Objective: To evaluate TNFalpha antagonist continuation rates in patients with rheumatoid arthritis (RA), ankylosing spondylitis (AS), or psoriatic arthritis (PsA).
Methods: We retrospectively reviewed the charts of patients treated with etanercept, infliximab, or adalimumab at our teaching hospital. Drug continuation was evaluated using Kaplan-Meier survival curves. The logrank test was used to compare continuation rates.
Results: We identified 442 patients who were prescribed 571 TNFalpha antagonist treatments between August 1999 and June 2005. Among them, 304 had RA, 92 AS, and 46 PsA. In the RA group, continuation rates were high with etanercept (n=157; 87% after 12 months and 68% after 24 months) and adalimumab (n=43, 83% and 66%) but significantly lower with infliximab (n=104, 68% and 46%; P=0.0001 vs. etanercept and P=0.01 vs. adalimumab). In the AS group, in contrast, infliximab (n=53) showed significantly higher continuation rates (89% and 83%) than did etanercept (n=39; 76% after 12 months: P=0.03). Overall continuation rates were higher in AS than in RA (P=0.01).
Conclusion: Continuation was better with etanercept than with infliximab in patients with RA, whereas the opposite was noted in patients with AS.