采用计算机模拟技术结合Caco-2细胞模型与溶出度试验考察国产盐酸曲美他嗪片的生物等效性

目的：采用计算机模拟技术结合Caco-2细胞模型和溶出度试验,对国产盐酸曲美他嗪生物等效性进行研究。方法：首先基于Caco-2单层细胞膜模型考察盐酸曲美他嗪的渗透性,获得其表观渗透系数P_app;第二步采用HPLC法测定溶出曲线来比较10家国产企业与原研生产的盐酸曲美他嗪片在5种不同pH条件下体外溶出行为的差异;最后采用Gastrol Plus^TM软件,导入本试验实测P_app,通过该软件转化为P_eff值,建立准确的体外溶出曲线与体内药动学曲线之间的相关性模型,基于该模型预测国产盐酸曲美他嗪片的药动学曲线,对其生物等效性进行体内外相关的研究。HPLC测定法：C₁₈柱,以0.287%无水庚烷磺酸钠-甲醇（55：45）为流动相,检测波长为231 nm,流速1.0 mL·min^-1;溶出度方法：分别以0.05 mol·L^-1盐酸溶液,pH 1.2、pH 4.0、pH 6.8缓冲盐溶液和水为溶出介质,桨法50 r·min^-1,溶出体积900 mL,分别考察片剂在上述5种溶出介质中5,10,5,20,30,45,60,90 min取样的溶出曲线。结果：盐酸曲美他嗪的表观渗透系数P_app值随着药物浓度的增加反而下降,属于中等渗透的药物;不同pH的溶出介质对盐酸曲美他嗪片的溶出行为无区分性;但在每种溶出介质中,国外原研片剂溶出较慢,与国产片剂的溶出行为存在明显差异,多数国产片剂快速溶出;采用Gastrol Plus^TM软件从药物在体内具有不同释放速率时的体内吸收情况与通过体外溶出曲线模拟体内吸收情况两个方面进行模拟研究,结果显示现有的国产盐酸曲美他嗪片与原研片剂在体内能够生物等效。结论：尽管国产盐酸曲美他嗪片的体外溶出曲线与原研片剂存在差别,但体内生物等效的可能性极大。Gastrol Plus^TM软件能够预测口服固体制剂与原研制剂的生物等效性,可在一致性评价工作中推广应用。

Study on the bioequivalence of trimetazidine hydrochloride tablets by using computer simulation technique combined with dissolution testing and Caco-2 cell monolayer models

OBJECTIVE To study the bioequivalence of domestic trimetazidine hydrochloride by computer simulation technique combined with Caco-2 cell model and dissolution test. METHODS Caco-2 cell monolayer models were used to determinate the apparent permeability coefficient (P_app) of TMZ, and the dissolution profiles which determinated by HPLC were used to compare of the difference between the domestic and reference preparations in five pH dissolving media. Finally, Gastrol Plus^TM software was used to import the measured permeability coefficient P_app of this experiment, and the software was used to convert P_app into P_eff to establish an accurate in vitro dissolution curve and in vivo pharmacokinetic curve. HPLC assay:C18 column with 0.287% anhydrous sodium heptane sulfonate-methanol (55:45) as mobile phase, detection wavelength at 231 nm, flow rate 1.0 mL min^-1; dissolution method:0.05 mol·L^-1 hydrochloric acid solution, pH 1.2, pH 4.0, pH 6.8 buffered saline solution and water as dissolution medium, stirring paddle method 50 r·min^-1, dissolution volume 900 mL, respectively, to examine the dissolution curve of tablets in the above five dissolution media at 5, 10, 5, 20, 30, 45, 60, 90 min sampling.RESULTS The apparent permeability coefficient (P_app) of TMZ decreased with the increase of the drug concentration,and TMZ is a moderately permeable drug. The dissolution behavior of TMZ tablets in different pH solution media was indistinguishable. However, in each solution medium, the dissolution behavior of the reference tablet was significantly different from that of the traditional tablets, and most of the domestic tablets were released rapidly. The absorption behavior of the drugs with different release rates and dissolution curves in the gastrointestinal tract was predicted by Gastrol Plus^TM. The results showed that the domestic tablets were bioequivalent to the reference tablet in vivo. CONCLUSION Although the dissolution curves of domestic TMZ tablets are different from that of the reference tablet, the prediction results revealed that domestic tablets were probably bioequivalent to the reference tablet. The Gastrol Plus^TM can predict the bioequivalence of the oral solid preparation, and can be widely used in drug re-evaluation.