内源性药物碘制剂的生物等效性研究

目的：以卵磷脂络合碘的人体生物等效性研究为例,探讨内源性药物的生物等效性研究方法。方法：对内源性及其他来源（饮食性）的碘进行控制。24名健康受试者进行双周期、双交叉、单剂量口服9片卵磷脂络合碘试验品和参比品,采用砷铈催化分光光度法测定血、尿中碘的浓度,用DAS2.1.1软件计算药动学参数,并进行生物等效性检验。结果：试验品与参比品的血碘平均净浓度增加值分别为16.8%和19.0%,尿碘回收率分别为84.5%和83.3%。计算同一周期的尿碘净排泄量,用尿碘累积净排泄量（Ae0-t）、最大净排泄速率（Rmax）进行生物等效性分析。本实验研究表明卵磷脂络合碘受试制剂与参比制剂具有生物等效性。结论：具有生物自稳定机制的内源性药物的生物等效性研究,实验设计更加复杂,各种内外因素对结果影响较大,需要尿药浓度结合背景扣除。

Bioequivalence study of endogenous drugs by iodine preparations

AIM. To study the bioequivalence of endogenous drug of iodized lecithin. METH- ODS： The endogenous and other sources （diet） iodine need to he controled. By a two-period cross-over trial, a total of 24 healthy volunteers were randomized to two groups to receive 9 io- dized lecithin tablets （test or reference formula- tion）. The concentrations of iodized lecithin in serum or urine were determined by arsenic-ceri- um catalytic spectrophotometric method. The pharmacoMnetic parameters were measured by DAS2.1.1 software. RESULTS.The value added of the average net concentration of blood iodine are 16.8% （test formulation） and 19.0% （refer- ence formulation）, and the recovery rate of uri- nary iodine are 84.5% and 83.3%. The net ex- cretion of urinary iodine were subtracted from the amount obtained on the drug dosing day, and the bioequivalence analysis was done according to the baseline-adjusted parameters （Ae0-24h： cumulative urinary excretion from 0 to 4g hours, Rmax. maximal rate of urinary excretion）. The test and reference preparations of iodized lecithin were bioequivalent. CONCLIJSION. It is a com- plicated design for the study of the bioequiva- lence of endogenous drug. Various kinds of in vivo and in vitro factors have a great influence on the result, and background need to be deduc- ted.