Is tapering or discontinuation of biologic treatment in patients with radiographic and nonradiographic axial spondyloarthritis reasonable? : A local cohort study.

Objective: We retrospectively determined factors predicting biologic treatment discontinuation or tapering in patients with axSpA.

Materials and methods: We included 63 nonradiographic axSpA (nr-axSpA) and 138 radiographic axSpA (r-axSpA) patients on biologic treatments for at least 1 year. The biologic dosing intervals were increased in patients who had been in remission for at least 6 months. In patients whose biologic dosing intervals could be increased by 100% for at least 6 months, the agents were stopped at the end of that time. In patients for whom the biologic agents were stopped or tapered, relapse was defined as a Bath Ankylosing Spondylitis Disease activity index score > 4 and a CRP level > 10 mg/L.

Results: The median duration of biologic treatment (all patients) was 2 (1-11) years. Logistic regression analysis did not identify any independent predictor of treatment discontinuation. NSAID use was the only independent predictor of tapering (p = 0.001). The time to relapse after tapering was shorter in patients with r‑axSpA than nr-axSpA (25.97 vs. 39.53 months; p = 0.05). The time to relapse in patients with r‑axSpA was considerably shorter than that in patients with nr-axSpA (5.14 vs. 13 months; p = 0.001). All r‑axSpA patients relapsed over the follow-up period; only 2 nr-axSpA patients did not relapse.

Conclusion: The most significant independent predictor of relapse was NSAID use during treatment. For axSpA patients in remission, tapering of the biologic dosing intervals is more appropriate than discontinuation.