比伐点定在中国人群药代动力学、药效学及安全性研究

【作者】 柴栋；

【导师】 王睿；

【作者基本信息】 中国人民解放军军事医学科学院 ， 药理学， 2011， 博士

【摘要】 目的初步研究比伐卢定在中国人群中的药代动力学、药效学以及安全性,建立PK/PD模型,设计适用于临床PCI围手术期的给药方案。方法①采用高效液相色谱串联质谱(LC-MS/MS)建立比伐卢定血药浓度测定方法,并考察方法的专一性、灵敏度、精密度、准确度、回收率、样品稳定性、稀释效应以及基质效应。②按入选、排除标准,筛选36名中国健康受试者,男女各半,分为三组,采用开放、单次给药、剂量爬坡设计,分别给予0.5,0.75,1.05mg/kg比伐卢定单次静脉推注,于给药前、给药后0,5,10,20,30,45,60,80,120,240 min共11个时间点于对侧上臂静脉各取血10ml,监测血药浓度和凝血功能变化,其中3ml用于血药浓度测定,3ml用于凝血四项(部分凝血活酶时间,凝血酶时间,凝血酶原时间,纤维蛋白原)测定,4ml用于活化凝血时间测定。方案经伦理委员会审批同意,受试者均签署知情同意书。应用winNonlin 5.2.1软件非房室模型计算t1/2、Cl、Vd、AUC等药代动力学参数,明确比伐卢定药代特征,观察药物效应与浓度关系,分析药效动力学特征。③以比伐卢定单次给药血药浓度以及活化凝血时间为指标,应用WinNonlin 5.2.1软件,进行模型模拟,建立比伐卢定药代动力学、药效动力学以及药代/药效统一模型,计算模型参数,并进行验证。④根据临床需求,应用PK/PD模型模拟比伐卢定序贯给药(静脉推注后静滴)体内药代动力学、药效学过程,设计序贯给药方案和血浆样本采集点。筛选12名中国健康受试者,男女各半,按设计方案(0.75mg/kg静脉推注后,1.75mg/kg/h静脉持续点滴4h)序贯给药,于给药前、推注结束静滴开始后0,10,30,60,120,240,245,250,260,285,300,320,360,480min共15个时间点于对侧上臂静脉各取血10ml,监测血药浓度、凝血功能变化,分析给药方案的临床适用性,并与模型结果进行对比,验证模型的适用性。⑤收集比伐卢定单次以及序贯给药临床试验期间,受试者的症状、体征、实验室检测等安全性数据,通过给药前后组间、组内变化差异比较,进行比伐卢定在中国人群安全性分析。⑥采用SAS 9.1.3软件进行统计分析。定量指标的描述包括例数、均数、标准差。分类指标的描述包括各类的例数及百分比。检验水准取0.05,P值小于或等于0.05被认为组间差别具有统计学意义。定量指标组间比较,如果满足正态性和方差齐性,采用F检验。否则采用非参数K-W检验。两两分析时,采用成组设计t检验或校正t检验。自身前后比较,采用配对t检验。结果①建立了比伐卢定血药浓度测定的LC-MS/MS方法,其专一性、灵敏度、精密度、准确度、回收率、样品稳定性、稀释效应以及基质效应均达到药代动力学检测要求,最低定量限为20μg/L,工作标准曲线线性范围是20-10000μg/L。②单次静脉推注0.5、0.75、1.05mg/kg比伐卢定的主要药代动力学参数: t1/2分别为0.41±0.12,0.49±0.18,0.46±0.15 h;Cl分别为0.50±0.24,0.38±0.06,0.53±0.24 L/h/kg;Vd分别为0.29±0.13 , 0.26±0.10 , 0.33±0.15L/kg ; MRT分别为0.37±0.06 , 0.45±0.12 ,0.43±0.08h;各剂量组间无统计学差异,P>0.05。比伐卢定主要药代动力学参数:t1/2为0.45±0.15h;Cl为0.47±0.21 L/h/kg ;Vd为0.30±0.13 L/kg; MRT为0.41±0.10h。三剂量组C0分别为4902.84±4556.64、6495.15±4659.54、6805.62±4130.55μg/L;AUC0～t分别为1126.91±352.93、1968.24±359.28、2292.34±903.91h?μg/l,C0、AUC0~ t随剂量的增加而基本成比例增加,各剂量组剂量归一化的C0和AUC0～t差异无显著性统计学意义,P>0.05。男性、女性的药代动力学参数:t1/2分别为0.48±0.17,0.43±0.13h;Vd分别为0.31±0.15,0.28±0.10 L/kg;Cl分别为0.48±0.26,0.46±0.14 L/h/kg;MRT分别为0.39±0.09,0.35±0.08h,组间无统计学差异,P>0.05。③单次静脉推注0.5、0.75、1.05mg/kg比伐卢定,给药即刻ACT达到峰值, Emax分别为237.13±49.31、244.67±40.52、281.79±31.72 s,时效曲线与药时曲线平行。其他药效指标,如部分凝血活酶时间、凝血酶时间、凝血酶原时间也在给药后即可达到峰值,时效曲线与药时曲线平行。④经房室模型模拟,比伐卢定静脉注射二房室线性代谢药代动力学模型AIC值最小,药效动力学采用有基础效应的M-M equation模型,建立比伐卢定PK/PD统一模型,模型数理参数分别为Vc=0.12,k10=3.54,k12=0.75,k21=1.44,E0=126.87,Emax=340.03,EC50=4258.03。经验证,单次静脉注射比伐卢定模拟值均落在实测值的95%置信区间内。⑤比伐卢定0.75mg/kg静脉推注,1.75mg/kg/h静脉持续点滴4h,其血药浓度波动在3000-4500μg/L之间,对应的ACT值波动在220-240s之间。比伐卢定序贯给药模拟值均落在实测值的95%置信区间内。⑥比伐卢定单次或序贯给药前后,除血压平均下降4-5mmHg外,其他症状、体征、实验室检查在正常范围之内,变化无临床意义。试验期间共出现5例不良事件,其中3例与药物有关,为轻度黏膜出血,均发生在序贯给药组。结论①建立了比伐卢定血药浓度测定LC-MS/MS方法,方法学达到临床药代动力学研究所需检测要求。②中国健康受试者单次静脉推注比伐卢定,在0.5-1.05mg/kg范围内,消除过程符合线性代谢特征,半衰期约为0.45h。静脉注射比伐卢定体内过程无性别差异。③比伐卢定静脉注射起效迅速,维持时间短暂,抗凝作用与其血药浓度密切相关,呈浓度依赖性,无性别差异。④比伐卢定药代动力学符合二房室线性代谢模型,药效动力学符合有基础效应的M-M equation模型,研究所建立的比伐卢定PK/PD模型能有效模拟临床疗效。⑤比伐卢定序贯给药(0.75mg/kg静推后,1.75mg/kg/h静脉持续点滴),可以满足临床有效性需求。⑥比伐卢定静脉注射在0.5~1.05mg/kg范围内,或比伐卢定0.75mg/kg静推后,1.75mg/kg/h静脉持续点滴4h序贯给药,在中国人群有良好的安全耐受性。更多还原

【Abstract】 Objective To study the pharmacokinetics, pharmacodynamics and safety of bivalirudin in healthy Chinese volunteers, and to develop the Pharmacokinetic-Pharmacodynamic(PK/PD)model of bivalirudin to design suitable dosage regimen of bivalirudin during percutaneous coronary intervention (PCI) operation.Methods①A method of liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the determination of bivalirudin concentration in plasma was developed, and the methodology was assayed including the specificity,sensitivity, precision, average recovery ratio, stability, dilution effect and matrix effect.②Applying the open, single dose and dose climbing design, 36 healthy Chinese volunteers were enrolled and divided into 3 different groups for the clinical trial, evenly male and female. The three groups were administrated by one bolus of 0.5,0.75,1.05mg/kg bivalirudin respectively. 10mL blood samples were obtained at predetermined time points before and after bivalirudin administation, which is 0,5,10,20,30,45,60,80,120,240 min, 3mL of which was used for determining the bivalirudin concentration in plasma, 3ml for assaying the four indicators of blood coagulation ( PT, APTT, TT and FIB), 4ml for monitoring the ACT. The protocol was agreed by ethic committee, and informed consent form was signed by every volunteer. The primary pharmacokinetic parameters were t1/2、C1、Vd、AUC that were caculated using WinNonlin 5.2.1 through non-compartment models , and the relationship of concentration and effect was observed, which ensured the PK/PD feathers of the Bivalirudin.③the pharmacokinetic-pharmacodynamic data from the clinical trial was used to develop PK,PD and PK/PD model by winNonlin 5.2.1 compartment model. The feasibility of the PK/PD model was assayed by comparing the results of model and detection.④According to the clinical demand, by using the developed PK/PD model to simulate the Pharmacokinetic-Pharmacodynamic process of Bivalirudin, the Sequential dosing regimen was designed. 12 healthy Chinese volunteers were selected for the trial and administrated the bivalirudin sequential regimen (0.75 mg/kg bolus followed by a 1.75 mg/kg/h infusion for 4h). 10mL blood samples were obtained at predetermined time points before and after bivalirudin adminstration, which is 0,10,30,60,120,240,245,250,260,285,300,320,360,480min. which was used to determine the concentration and assay the changes of blood coagulation. Then, by comparing the results of the model with the detection, the feasibility of developed PK/PD model was explored.⑤The signs and symptoms of the research subjects in the single dosing and sequential dosing clinical trial were collected to analyze the safety of the Bivalirudin in Chinese population.⑥SAS 9.1.3 was used to conduct the statistic analysis. Quantitative index includes samples, average and standard deviation. Classification index includes a variety of numbers and percentages. The level of significance is 0.05, if the value of P less than or equal to 0.05 is considered statistically significant. According to different cases, F-test, K-W test or t-test was used.Results①A simple, rapid LC-MS/MS method was developed and validated for the identification and quantification of bivalirudin in human plasma and the specificity,sensitivity, precision, average recovery ratio, stability, dilution effect and matrix effect all satisfied the pharmacokinetic detection requirements. The assay demonstrated linearity from 20 to 20000 ug/L bivalirudin in plasma, with a detection limit of 20 ug/L.②Administrated by one bolus of 0.5,0.75,1.05mg/kg respectively, the main Pharmacodynamic parameters of bivalirudin: t1/2 is 0.41±0.12,0.49±0.18,0.46±0.15 h respectively; Cl is 0.50±0.24,0.38±0.06,0.53±0.24 L/h/kg respectively;Vd is 0.29±0.13,0.26±0.1,0.33±15 L/kg respectively;MRT is 0.37±0.06,0.45±0.12,0.43±0.08h. There is no statistically significant differences within different dosage groups (P>0.05).C0 is 4902.84±4556.64、6495.15±4659.54、6805.62±4130.55μg/L respectively; AUC0～t is 1126.91±352.93、1968.24±359.28、2292.34±903.91h*μg/l respectively,C0、AUC0~t increases in proportion to the increase of doses,and there is no statistically significant differences among C0、AUC0~t of each dose group normalized by dose ( P>0.05). The main Pharmacodynamic parameters of male and femal: t1/2 is 0.48±0.17,0.43±0.13h;Vd is 0.31±0.15,0.28±0.10 L/kg;Cl is 0.48±0.26,0.46±0.14 L/h/kg;MRT is 0.39±0.09,0.35±0.08h. There is no difference between male and femal(P>0.05)。③Bivalirudin administrated by once bolus of 0.5、0.75、1.05mg/kg, the value of ACT reaches the peak at once, and the Emax is 237.13±49.31、244.67±40.52、281.79±31.72 s respectively, time-effect curves and time-concentration curve are paralleled.④According to the stimulating of the bivalirudin compartment model, the value of AIC is minimum in the two-compartment model. The pharmacodynamic model fit the M-M equation model. The parameters of the PK/PD model are as follows: Vc=0.12,k10=3.54,k12=0.75,k21=1.44,E0=126.87,Emax=340.03,EC50=4258.03. all the model value lies in the 95% confidence interval.⑤Sequential dosing of bivalirudin (0.75 mg/kg bolus followed by a 1.75 mg/kg/h infusion for 4h) the concentration in plasma waved between 3000-4500ug/L, the value of ACT is between 220-240s, the value of PK/PD model lies in the 95% confidence interval too.⑥Most of the signs and the symptoms of the volunteers before and after the single or the sequential dosing of bivalirudin have no statistically significant differences (P>0.05), except Blood pressure decreased 4-5mmHg averagely. During the trials, 5 cases totally appeared adverse events, including 3 cases related with Bivalirudin, with mild mucosal bleeding, all of which were in the sequential group.Conclusions①The developed assay method was successfully applied to a pharmacokinetic (PK) study in healthy volunteers after intravenous administration of bivalirudin.②Administrated by once bolus on Chinese healthy volunteers, the excreting process of Bivalirudin was first-order elimination in the range of 0.5-1.05mg/kg.③Bivalirudin has a fast and short effect, and the drug effect has relation with the concentration in plasma, showing concentration-dependent manners.④Pharmacokinetics of bivalirudin in plasma after intravenous administration were fitted to the two-compartment model with the first-order elimination and pharmacodynamics of bivalirudin was fitted to the M-M equation model. The developed PK/PD model can predict the clinical effect accurately.⑤Sequential dosing (0.75 mg/kg bolus followed by a 1.75 mg/kg/h infusion for 4h) can meet the clinical demand effectively.⑥Bivalirudin regimen in the range of 0.5~1.05mg/kg or Sequential dosing (0.75 mg/kg bolus followed by a 1.75 mg/kg/h infusion for 4h) has good safety and tolerance in Chinese population.更多还原