P574 Incidence and indicators of suboptimal response to tumour necrosis factor antagonist therapy in Chinese patients with inflammatory bowel disease: Results from the EXPLORE study

Abstract

Abstract Background Inflammatory bowel disease (IBD) patients may experience a suboptimal response to anti-tumour necrosis factor (TNF) therapy. In China, these data are limited. The EXPLORE study aimed to assess the incidence and indicators of suboptimal response to first-line anti-TNF agents in IBD patients in real-world practice in the newly industrialised countries. Methods The EXPLORE study was a multinational, retrospective chart review study. In the China subgroup, adult patients from 10 centres diagnosed with ulcerative colitis (UC) or Crohn’s disease (CD) and who initiated first anti-TNF treatment between March 2010 and March 2015, were included. The cumulative incidence (CI) of suboptimal response was assessed over 24 months since the anti-TNF initiation. The indicators of suboptimal response included: IBD-related hospitalisation, dose-escalation, discontinuation including switch to another anti-TNF, non-biologic therapy augmentation, or IBD-related surgery. Primary non-response (PNR) and secondary loss of response (SLOR) were defined as any suboptimal response indicator at <4 and ≥4 months after anti-TNF initiation, respectively. Results Overall, 287 first-line anti-TNF treated patients (35 UC; 252 CD) were included: male, UC 54.3% (n = 19), CD 74.6% (n = 188); mean (SD) age (years), UC 43.1 (14.2), CD 31.9 (11.3); median (min-max) disease duration (years), UC 1.0 (0–9), CD <1 year (0–21); median (min-max) follow-up (months), UC 27.6 (24–60), CD 40.0 (24–60). At 12 and 24 months, the CI of suboptimal response to first anti-TNF treatment was 51.4% and 75.7% in UC, 45.4% and 57.0% in CD, respectively (Figure 1). The median time to the first suboptimal response was 7.2 months in UC and 14.3 months in CD. The CI of PNR was 31.2% in UC and 33.7% in CD. The CI of SLOR was 29.4% and 64.7% in UC, 17.7% and 35.2% in CD at 12 and 24 months, respectively. The most frequent first suboptimal response indicator was ‘discontinuation of anti-TNF therapy’ in UC patients (56.3%) while for CD patients it was ‘IBD-related hospitalisation’ (56.1%) followed by ‘augmentation with non-biological therapy’ in both cohorts (UC 31.3%; CD 22.8%). Conclusion Approximately three-quarters of UC and over half of CD patients experienced a suboptimal response to their first anti-TNF agent at 24 months. Given the high unmet needs observed with anti-TNF therapies in China, IBD patients may benefit from greater optimisation of care and new biologic options.