Loss of response to anti-TNFα agents depends on treatment duration in patients with inflammatory bowel disease.

Abstract

SummaryBackgroundInflammatory bowel disease (IBD) is often managed with anti‐tumour necrosis factor‐α therapy (anti‐TNFα), but treatment efficacy is compromised by high annual rates of loss of response (13%‐21% per patient‐year).AimsTo assess whether the incidence of loss of response decreases with longer treatment durationMethodsThis was a multicentre, retrospective cohort study of patients with ulcerative colitis (UC) or Crohn's disease (CD) who received anti‐TNFα for at least 4 months between 2011 and 2019. We studied the incidence of loss of response as a function of treatment duration, employing parametric survival modelling. Predictors of loss of response were identified by Cox regression analysis. Secondary outcomes included overall anti‐TNFα discontinuation and dose escalation.ResultsWe included 844 anti‐TNFα treatment episodes in 708 individuals. Loss of response occurred in 211 (25.0%) episodes, with anti‐drug antibodies detected in 66 (31.3%). During the first year, the incidence of loss of response was three‐fold higher than after four years of treatment (17.2% vs 4.8% per patient‐year, P < 0.001). The incidence of anti‐TNFα discontinuation (28.6% vs 14.0% per patient‐year, P < 0.001) and dose escalations (38.0% vs 6.8% per patient‐year, P < 0.001) also decreased significantly from the first year to after four years, respectively. Predictors of loss of response included UC (vs CD, adjusted hazard ratio [aHR] 1.53, 95% CI 1.10‐2.15) and, among patients with CD, stricturing or penetrating disease (aHR 1.68, 95% CI 1.15‐2.46) and male sex (aHR 0.55, 95% CI 0.38‐0.78). Immunomodulators were protective against loss of response with anti‐drug antibodies (aHR 0.42, 95% CI 0.24‐0.74).ConclusionsPatients with sustained benefit to anti‐TNFα after 2 years are at low risk of subsequent loss of response.