Clinical Relapse Common After Infliximab Withdrawal in Ankylosing Spondylitis

Nearly two-thirds of patients with ankylosing spondylitis (AS) who achieved clinical remission on infliximab demonstrated symptom flares and clinical relapse soon after infliximab withdrawal. Further, following reintroduction, approximately half of these individuals had a clinical response comparable to that seen prior to initial discontinuation, according to a study published in Arthritis Research & Therapy.

Some clinicians note that the use of antitumor necrosis factor (anti-TNF) medications like infliximab – because of high cost and likely long-term side effects – should be reduced in patients with AS who demonstrate good clinical responses, with the potential for complete discontinuation in those achieving clinical remission. Investigators sought to assess the consequences of medication withdrawal on AS disease course and relapse rates, along with the effect of anti-TNF reintroduction among those who had relapse.

A multicenter, prospective, observational study recruited 107 active patients with AS receiving an initial course of anti-TNF therapy with infliximab. A total of 36 participants (34%; mean age, 38.52 years; mean disease duration, 8.94 years) had disease remission and were included for analysis in this study. Disease variables were assessed at baseline and every 6 to 8 weeks over the course of 1 year.

Following discontinuation of infliximab, 12 participants (33.3%) remained symptom free and in remission, while 21 (58.3%; mean age, 40 years; mean disease duration, 9 years) had clinical relapse during follow-up. When infliximab was later safely reintroduced, just over half (n=11) of these patients were again able to achieve clinical remission comparable to that prior to withdrawal, while another 3 showed inadequate clinical response to infliximab reintroduction. Those not responding to infliximab after reintroduction were placed on a different anti-TNF agent. There were no biologic or clinical factors significantly associated with relapse occurrence across 12 months of follow-up.

Study limitations included small sample size, use of only infliximab for AS treatment, lack of dose reduction before complete withdrawal, narrow remission window of 6 to 12 months, and study commencement prior to release of the latest remission and relapse criteria.

“Overall, the results we reported here suggest that the decision to withdraw treatment should be taken with considerable caution, and it seems unreasonable to propose withdrawal as an objective of the treatment strategy, at least at present, in the absence of any objective predictive factors of persistent clinical remission after treatment withdrawal,” the authors noted.

This work was supported by Merck Research Laboratories.

Reference

Moreno M, Gratacós J, Torrente-Segarra V, et al. Withdrawal of infliximab therapy in ankylosing spondylitis in persistent clinical remission, results from the REMINEA study. Arthritis Res Ther. 2019;21(1):1-6.