P755 Long-term need for restart of biologics after withdrawal in patients with Inflammatory Bowel Disease in mucosal healing

Abstract

Abstract Background In patients with inflammatory bowel disease (IBD) on biologic therapy, once remission has been achieved, withdrawal is a frequent issue in clinical practice that generates uncertainty in aspects such as the reduction of adverse effects and costs, but also the risk of recurrence of activity and the need to restart treatment. The aim of this study was to determine the rate of long-term reintroduction of biologics after withdrawal due to mucosal healing (MH) in IBD, the response to reintroduction and the associated factors. Methods Observational, descriptive, single-centre, retrospective, descriptive study of 178 cases in 164 patients diagnosed with ulcerative colitis (UC) or Crohn's disease (CD) who were withdrawn from anti-tumor necrosis factor (anti- TNF) therapy once MH had been demonstrated, between July 2009 and February 2022. Demographic and phenotypic characteristics of IBD, characteristics of biologic and immunosuppressive therapy, analytical and endoscopic/histological variables at the time of withdrawal were collected. We analysed the risk of restarting biologics due to clinical relapse and response to reintroduction of treatment. We evaluated possible factors related to the risk of restarting treatment and response to treatment. Results We included 178 cases. 123 CD and 55 UC. Most had received infliximab (62.9%) and the main indication was corticodependence (68%). Median follow-up was 78 months (IQR 59-95). Clinical relapse occurred in 69% of cases and 61.2% required reintroduction of biologics, with the probability of retreatment at 1, 3, 5 and 7 years being 19.4%, 50%, 60% and 63.4%, respectively (Figure 1). The response to reintroduction was 86.2%. Only 1.68% required surgery during follow-up. Univariate analysis showed higher risk of re-introduction at younger age at diagnosis (23 vs 30 vs 30, p 0.022) and at withdrawal (32 vs 40, p 0.019) and longer follow-up time after withdrawal (82 vs 71, p 0.026). Multivariate analysis also identified the indication for corticodependence (p 0.046). Conclusion The risk of relapse and re-starting treatment is high in the long term after withdrawal of biologic therapy for MH in IBD. Younger age at diagnosis and withdrawal, indication for corticodependence and long-term follow-up are risk factors for poor outcome. Reintroduction of treatment is very effective with low complication rates.