Objectives

To study infliximab (IFX) pharmacokinetics in children with inflammatory bowel disease (IBD) during induction therapy to predict outcome and explore if other covariates influenced outcome.

Study design

All children with IBD starting IFX therapy (5 mg/kg at weeks 0, 2, 6, and 12) for active luminal disease from May 2017 to May 2019 were included and followed prospectively. Patients were sampled at multiple timepoints during induction (trough concentrations and peak concentration at weeks 0, 2, 6, and 12, and intermediate concentration at weeks 1-4). IFX concentrations and cumulative drug exposure were correlated with outcome at 6 months. Endoscopic remission was defined as Simple Endoscopic Score for Crohn's Disease of <3 or Mayo endoscopic subscore of 0, and deep remission as endoscopic with clinical remission (Pediatric Ulcerative Colitis Activity Index/Pediatric Crohn's Disease Activity Index of <10).

Results

There were 252 serum induction concentrations obtained from 32 patients (81% on concomitant thiopurines). Children in endoscopic remission (all in deep remission) at 6 months had significantly higher drug concentrations from week 4 onward. A receiver operating characteristics curve analysis identified IFX trough concentrations at week 12 of ≥5.0 μg/mL and area under the curve at weeks 0-12 of ≥4056.0 μg∗day/mL as the minimal target to achieve endoscopic remission at 6 months (area under the receiver operating characteristics curve, 0.796 [95% CI, 0.62-0.97] and area under the receiver operating characteristics curve, 0.778 [95% CI, 0.61-0.94], respectively). In addition, our findings suggest that proteomic analysis may help to understand IFX response.

Conclusions

Higher IFX exposure during induction therapy in pediatric patients with IBD is associated with significantly better endoscopic and deep remission rates at 6 months. Drug concentrations differentiate remitters from nonremitters from week 4 after induction onward.

中文翻译：

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诱导期间的英夫利昔单抗浓度可预测联合治疗下炎症性肠病儿科患者的内镜缓解

目标

研究诱导治疗期间炎症性肠病 (IBD) 儿童的英夫利昔单抗 (IFX) 药代动力学，以预测结果并探索其他协变量是否影响结果。

学习规划

纳入 2017 年 5 月至 2019 年 5 月期间因活动性管腔疾病而开始 IFX 治疗的所有 IBD 儿童（第 0、2、6 和 12 周 5 mg/kg）并进行前瞻性随访。在诱导期间的多个时间点对患者进行采样（第 0、2、6 和 12 周的谷浓度和峰值浓度，以及第 1-4 周的中间浓度）。IFX 浓度和累积药物暴露与 6 个月时的结果相关。内镜下缓解定义为克罗恩病的简单内镜评分<3 或 Mayo 内镜评分为 0，深度缓解定义为内镜下临床缓解（小儿溃疡性结肠炎活动指数/小儿克罗恩病活动指数 <10）。

结果

从 32 名患者中获得了 252 种血清诱导浓度（81% 同时使用硫嘌呤）。从第 4 周开始，6 个月时内镜缓解（全部处于深度缓解）的儿童药物浓度显着升高。接受者操作特征曲线分析确定，第 12 周的 IFX 谷浓度≥5.0 μg/mL，第 0-12 周的曲线下面积≥4056.0 μg*day/mL 作为 6 个月时实现内镜缓解的最低目标（面积受试者工作特征曲线下面积分别为 0.796 [95% CI, 0.62-0.97] 和受试者工作特征曲线下面积 0.778 [95% CI, 0.61-0.94]）。此外，我们的研究结果表明，蛋白质组学分析可能有助于理解 IFX 反应。

结论

在儿童 IBD 患者的诱导治疗期间，较高的 IFX 暴露与 6 个月时显着更好的内镜和深度缓解率相关。从诱导后第 4 周开始，药物浓度将汇款人与非汇款人区分开来。