P673 Achievement of tight control based on serum C-reactive protein and albumin correlated with better outcomes in Japanese Crohn’s disease patients treated with biologics

Tight control management based on the clinical symptoms together with biomarkers has been proven to be more effective than conventional clinical management for Crohn’s disease in the CALM study. However, there are insufficient data on what are indicators to be used for tight control management. Optimal biomarkers and their optimal standards that can be used conveniently in daily clinical practice are desired. We aimed to clarify whether tight control management based on serum biomarkers (C-reactive protein or albumin) results in better outcome, and to identify their optimal standards for tight control management in Japanese Crohn’s disease patients treated with biologics. We reviewed the treatment courses of 245 patients with Crohn’s disease who were naïve to biologics and treated with anti-TNF agents (185 with Infliximab and 60 with adalimumab). Tight control was set at CRP < 0.3, CRP < 0.5, Alb ≥ 4.0 or Alb ≥ 3.8. The association between the achievement of tight control at Week 8 or 24 and major adverse outcomes (hospitalisation, surgery and discontinuation due to treatment failure) were analysed using the Log-rank test. To identify factors affecting major adverse outcomes, we also performed multi-variate analyses using a Cox proportional hazards model with clinical characteristics and serum biomarkers as covariates. In 223 patients followed for more than 8 weeks, the rate of major adverse outcomes was significantly higher in patients with CRP ≥ 0.3, CRP ≥ 0.5, Alb < 4.0 or Alb < 3.8 at Week 8. In a multi-variate analysis, the fistulising type, CRP ≥ 0.5 and Alb < 3.8 were identified as independent risk factors for major adverse outcomes with hazard ratios of 2.2, 2.0 and 2.1, respectively. In 204 patients followed for more than 24 weeks, the rate of major adverse outcomes was significantly higher in patients with CRP ≥ 0.3, CRP ≥ 0.5, Alb < 4.0 or Alb < 3.8 at Week 24. In a multi-variate analysis, the fistulising type, CRP ≥ 0.5 and Alb < 3.8 were identified as independent risk factors for major adverse outcomes with hazard ratios of 2.3, 1.9 and 2.2, respectively. Tight control management may lead to avoidance of hospitalisation, surgery or discontinuation of anti-TNF agents in Japanese Crohn’s disease patients. Among serum biomarkers that can be used conveniently in daily clinical practice, CRP < 0.5 and Alb ≥ 3.8 were the best candidates for tight control management. We should achieve tight control until Week 24 with optimisation of anti-TNF agents or addition of immunomodulators.