人体中伊曲康唑及其活性代谢产物羟基伊曲康唑的整合药代动力学研究

目的: 羟基伊曲康唑(OH-ITZ)为目前临床一线抗真菌药伊曲康唑(ITZ)的主要活性代谢产物,其与ITZ有着相似的抗菌活性,且血药浓度较母体药物高,因此OH-ITZ的体内过程对临床疗效的影响研究不容忽视。本文旨在建立灵敏、快速的液相色谱-串联质谱法同时测定人血浆中ITZ及OH-ITZ,并应用整合药代动力学模型进行整体评价。方法: 血浆样品经沉淀蛋白后,以乙腈(甲酸 0.1%)-水(甲酸 0.1%)为流动相梯度洗脱,Zorbax XDB C₁₈柱分离,采用电喷雾电离源,以多反应监测(MRM)方式进行正离子检测。定量分析所用的离子反应分别为m/z 705 →m/z 392(ITZ),m/z 721→m/z 408(OH-ITZ)和m/z 386→m/z 122(内标,丁螺环酮)。结果: 测定血浆中ITZ及OH-ITZ的线性范围均为 0.50~500 ng/mL,日内、日间精密度(RSD)均小于 12.4%,准确度(RE)均在±7.5%以内;整合药动学研究结果显示综合浓度药-时曲线符合口服给药药物消除规律,整合后主要药动学参数t_1/2和AUC_0-∞分别为 19.5 h,5754 ng·h·mL^-1。结论: 本方法运行时间短、选择性强、灵敏度高、操作简便、血浆用量少,适用于ITZ及OH-ITZ的临床药代动力学研究;其整合药动学模型研究所获参数能够表征ITZ和OH-ITZ的整体处置规律,符合经典药代动力学模型特征。

Integrated pharmacokinetic study of itraconazole and its active metabolite-hydroxyitraconazole in human

AIM: Hydroxyitraconazole (OH-ITZ) is the magor active metabolite of itraconazole (ITZ) which is the first-line antifungal drug and it has antifungal activity similar to ITZ. Forther more, the plasma concentration of OH-ITZ is higher than that of ITZ. Therefore, it can not be ignored that the pharmacokinetics of OH-ITZ effect on the clinical therapeutic effects. This study was designed to develop a sensitive and rapid LC-MS/MS method for direct determination of ITZ and OH-ITZ in human plasma and to study the integrated pharmacokinetics of ITZ and OH-ITZ in human. METHODS: ITZ, OH-ITZ andinternal standard (buspirone) were pretreated from plasma OH-ITZ in human using protein precipitation with acetonitrile/methanol(1∶1). Chromatographic separation was achieved on an Agilent Zorbax-C₁₈ column (2.1 mm×50 mm, 3.5 μm) using a step gradient program with the mobile phase of 0.1% formic acid aqueous solution and acetonitrile with 0.1% formic acid, at a flow-rate of 0.50 mL/min. Electrospray ionization (ESI) source was applied and operated in the positive ion mode. Multiple reaction monitoring (MRM) mode with the transitions of m/z 705 →m/z 392, m/z 721→m/z 408 and m/z 386→m/z 122 was performed to quantify ITZ, OH-ITZ and IS, respectively. RESULTS: The linear concentration ranges of calibration curves for ITZ and OH-ITZ were 0.50-500 ng/mL. The inter- or intra-day precision (RSD) was less than 12.4% and the accuracy (RE) was within±7.5%. Based on the AUC weighting coefficients integration approach, the integrated pharmacokinetic parameters were calculated. The holistic t_1/2 and AUC_0-∞ were of 19.5 hr and 5754 ng·h·mL^-1 in human plasma after oral administration of 200 mg itraconazole. CONCLUSION: The method is sensitive, rapid, convenient, using less plasma and is proved to be suitable for clinical pharmocokinetics of ITZ and OH-ITZ. The holistic pharmacokinetic properties of ITZ and OH-ITZ were described successfully.