P014 Postoperative Recurrence in Crohn’s Disease Patients Treated with Adalimumab versus Infliximab: A Systematic Review and Meta-Analysis

Up to 80% of patients with Crohn's disease (CD) undergo intestinal resection at one point. However, the risk of post-operative recurrence (POR) increases with time, with half of these patients developing recurrence at five years after surgery. Treatment with anti-tumor necrosis factor (anti-TNF) agents has been shown to decrease the risk of clinical and endoscopic recurrence post-operatively. This meta-analysis aims to compare the rate of the two mostly commonly used anti-TNF agents (infliximab (IFX) and adalimumab (ADA)) and their efficacy in maintaining clinical and endoscopic remission in CD patients who were treated with adalimumab versus infliximab after surgery.A comprehensive search of Medline, EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews and Scopus was conducted from each database's inception to May 29th 2021. Comparative studies assessing the efficacy and safety of infliximab and adalimumab for postoperative CD patients were included. Primary outcomes included postoperative clinical and endoscopic remission. Secondary outcome was the risk of adverse events due to anti-TNF agents. Pooled event rates were calculated per person-year of follow-up.Four studies with total of 361 CD patients were included in the final analysis. Our meta-analysis showed no statistically significant difference in maintaining clinical and endoscopic remission rates between patients treated with infliximab and those with adalimumab (Pooled incidence rate ratio of 0.75 (95% CI 0.43-1.3), and 0.94 (95% CI 0.71-1.2), respectively) (Figure 1A, 2A). There were low to moderate heterogeneities (I2 = 57.1% for clinical remission and I2 = 0% for endoscopic remission). The funnel plot in each analysis indicated no publication bias, which was supported by Begg's and Egger's tests (Figure 1B, 2B). There was also no significant difference in the risk of adverse events between the two groups (RR= 0.56, 95% CI 0.068-4.5) (Figure 3).Our meta-analysis demonstrated comparable efficacy of infliximab and adalimumab in maintaining post-operative clinical and endoscopic remission in Crohn's disease, with similar rates of adverse events. Our meta-analysis was limited by the small number of total studies and patients included and the lack of randomized controlled trials.