Therapeutic considerations in spondyloarthritis patients who fail tumour necrosis factor antagonists

The tumour necrosis factor (TNF) antagonists have significantly improved quality of life and functional status in patients with spondyloarthritis (SpA). The excitement regarding the remarkable success of these agents is justified but challenges remain. In particular, alternative systemic therapies with proven efficacy for patients who fail TNF antagonists have been developed in rheumatoid arthritis but are not yet available in SpA. In this article, the approach to patients with psoriatic arthritis (PsA) or ankylosing spondylitis (AS) who fail TNF antagonists will be discussed with the goal of providing a path to the clinician, who must manage these patients amidst uncertainty. Three central questions will be addressed. Why does a particular SpA patient not respond to a TNF antagonist? How can the clinician improve the probability of treatment response in patients who fail a TNF antagonist? What specific approaches can be taken to control disease activity in PsA or AS following treatment failure with a TNF antagonist? Data from controlled trials, registries and pilot studies will be combined with expert opinion to address these important questions.