Abstract
BACKGROUND: Infliximab (IFX) is recognized as an effective drug for the treatment of pediatric Crohn's disease (CD), but approximately 23-60% develop secondary loss of response (LOR) to IFX. Currently, few studies have focused on the influencing factors on secondary LOR to IFX in pediatric CD patients. In this study, we aimed to analyze factors influencing the secondary LOR to IFX in pediatric CD patients. METHODS: A retrospective analysis was conducted of the clinical data for 69 CD patients treated with IFX in the department of gastroenterology of Beijing Children's Hospital between September 2015 and December 2022. Univariate analysis was conducted using the Log-rank test, and a Cox proportional hazards regression model was used to analyze the factors influencing secondary LOR to IFX. RESULTS: The study enrolled a total of 69 CD patients, including 41 males and 28 females. The median age at the first IFX administration was 12.0 (9.3, 13.7) years, and the median disease duration before IFX administration was 7.6 (3.4, 16.8) months. Among the 69 patients, 18 (26.1%) were assigned to the secondary LOR group and 51 (73.9%) were classified as the responder group. Univariate analysis of factors related to secondary LOR in CD patients treated with IFX included body mass index Z-score ≤-1, growth disorders, clinical response but failed to achieve clinical remission after IFX induction therapy, and combined treatment with IFX and immunomodulators for more than 6 months (P=0.03, 0.03, <0.001, 0.04, respectively). Moreover, multivariate Cox regression analysis revealed that clinical response but failed to achieve clinical remission after IFX induction therapy was an independent risk factor for secondary LOR to IFX [hazard ratio (HR) =7.746, 95% confidence interval (CI): 1.671-35.917, P=0.009]. In contrast, combined treatment with IFX and immunomodulators for more than 6 months was an independent protective factor for the secondary LOR to IFX (HR =0.251, 95% CI: 0.075-0.839, P=0.03). CONCLUSIONS: CD patients who had clinical response but failed to achieve clinical remission after IFX induction therapy were at increased risk for secondary LOR to IFX, while combined treatment with IFX and immunomodulators for more than 6 months reduced the risk of the secondary LOR to IFX.