Objective: TNF-alpha antagonists, infliximab (INF), etanercept (ETA) and adalimumab (ADA), have been demonstrated to be effective in controlling symptoms in SpAs. The aim of this study was to investigate the possibility of using ADA as a second or third choice.
Methods: A retrospective study was conducted in patients with SpA treated with TNF-alpha blockers who switched from INF or ETA to ADA, for inefficacy or adverse events. Kaplan-Meier survival curves were plotted to determine the rates of continuation of the first treatment (INF or ETA) as compared with the rates of continuation of the second or third treatment with ADA.
Results: A total of 1619 patients with SpA were treated with INF (35.3%), ETA (43.7%) and ADA (20.9%). In this cohort, ADA was started in 38 (2.34%) patients as a second anti-TNF-alpha drug and in 9 (0.56%) as a third anti-TNF-alpha drug. In SpA patients who failed the first anti-TNF-alpha, for whatever reason, survival curves for ADA (as a second anti-TNF-alpha) were significantly better than survival curves for these same patients on their first anti-TNF-alpha (overall: P < 0.0001; INF: P < 0.0011; ETA: P < 0.02).
Conclusion: Our retrospective study, resulting from real-life experience, showed that SpA patients who fail to respond to a first agent, INF or ETA, respond to ADA as a second-line drug regardless of the reason for switching.