单剂量的奈韦拉平

1、单剂量的奈韦拉平第1页，共45页，2022年，5月20日，2点14分，星期二摘要：两个随机、单剂量、交叉的生物利用度的研究结果，描述了奈韦拉平（是一种新型的非核苷抗逆转录病毒的药物）的药代动力学和口服生物利用度。 ABSTRACT: The results of two randomized, single-dose, crossover bioavailability studies are presented which describe the pharmacokinetics and oral bioavailability of nevirapine, a novel nonnucl

2、eoside antiretroviral drug. 第2页，共45页，2022年，5月20日，2点14分，星期二在第一个研究中，向12名健康男性志愿者体内短期静脉注射15mg奈韦拉平，或者口服50mg的片剂，或者口服参比溶液（50 mg/200 mL）。静脉注射完之后，奈韦拉平有一个较低的全身清除率(MeanS.D., Cl=1.40.3 L/h)和一个延长的消除相(t1/2=52.814.8 h; MRT =81.422.4 h). 。 In the first study 12 healthy male volunteers received nevirapine 15 mg via

3、short-term i.v. infusion or orally as a 50 mg tablet or reference solution (50 mg :200 mL). Following the i.v. dose,nevirapine had a low systemic clearance (MeanS.D., Cl=1.40.3 L/h) and a prolonged elimination phase (t1/2=52.814.8 h; MRT =81.422.4 h). 第3页，共45页，2022年，5月20日，2点14分，星期二奈韦拉平的绝对生物利用度分别为：注射

4、剂是939%，片剂和口服溶液是918%。在第二个研究中，24名健康男性志愿者服用200mg片剂奈韦拉平或者口服参比溶液（200 mg/200mL）。片剂和参比溶液的生物利用度没有显著的不同。 Nevirapine absolute bioavailability was 939% and918% for the tablet and oral solution, respectively. In the second study, 24 healthy male volunteers wereadministered nevirapine as a 200 mg production-line

5、 tablet or oral reference solution (200 mg/200 mL).There was no significant difference in bioavailability between the tablet and reference solution. 第4页，共45页，2022年，5月20日，2点14分，星期二总之，对50mg和200mg剂量的药代动力学参数进行比较，结果显示，服用临床相关剂量的奈韦拉平能够被很好的吸收。使用解卷积法得到的吸收曲线表明，这两种剂量或是每种剂量的给药途径没有由特定的酶诱导。Overall,comparison of t

6、he pharmacokinetic parameters between the 50 and 200 mg doses indicates that nevirapine is well absorbed at clinically relevant doses. The absorption profiles using deconvolution revealed no evidence of differential enzyme induction between the two doses or routes of administration following a singl

7、e dose. 第5页，共45页，2022年，5月20日，2点14分，星期二介绍：奈韦拉平的结构是二吡啶并二氮杂卓酮（如图），它是第一类适用于治疗人类免疫缺陷病毒（HIV）的非核甘类逆转录酶抑制剂。在细胞培养中，奈韦拉平通过与逆转录酶直接连接，抑制RNA依赖和DNA依赖的聚合酶活性。 Nevirapine, a dipyridodiaqepinone (Figure 1), was the first drug of the nonnucleoside reverse tran-scriptase inhibitor (NNRTIs) class to be approved for trea

8、ting the human immunodeficiency virus (HIV) infection in humans. By binding directly to reverse transcriptase, nevirapine inhibits the RNA-dependent and DNA-dependent polymerase activi-ties in cell culture第6页，共45页，2022年，5月20日，2点14分，星期二在临床试验中，当奈韦拉平与核苷类和蛋白酶类药物用于联合治疗时，能够证明奈韦拉平是强效的、持久的抗病毒药物。In clinical

9、trials, nevirapine has demonstrated potent and sustained antiviral activity when used in triple combination therapy with drugs of the nucleoside and protease inhibitor classes 第7页，共45页，2022年，5月20日，2点14分，星期二口服给药后，人体能够迅速的吸收奈韦拉平达到400mg。服用200mg剂量的奈韦拉平，给药4小时后，血浆浓度峰值达到大约2g/mL，尽管之后多重峰的次级峰值浓度也能被监测出。剂量达到200m

10、g时，血药浓度-时间曲线下面积和最大浓度呈线性关系。 In humans, nevirapine appears to be readily ab-sorbed following oral administration of doses up to 400 mg 7,8. Following a single 200 mg dose nevi-rapine peak plasma concentrations of approxi-mately 2g/mL are achieved by 4 h postdose,although subsequent multiple secondary

11、peak concentrations are also observed. Area under the plasma concentration time curve (AUC) and Cmax both exhibit dose linearity at doses up to 200 mg.第8页，共45页，2022年，5月20日，2点14分，星期二奈韦拉平的药代动力学特征是服用单一剂量后，有持续很长时间的药代动力学作用时期(t1/245h）奈韦拉平经过P450酶的代谢形成羟基葡糖苷酸它作为无活性代谢物主要被排泄到尿中。单剂量中不到3%作为原药排到尿中。 The pharmacoki

12、netics of nevirapine are also charac-terized by a prolonged pharmacokinetic dispositionphase (t1/245h)following a single dose. Nevirap-ine undergoes extensive P450 metabolism to hydroxylated glucuronides, which are largely excreted into the urine as inactive metabolites. Less than 3% of a dose is ex

13、creted in urine as parent compound. 第9页，共45页，2022年，5月20日，2点14分，星期二加倍剂量的药代动力学特征是，当从单剂量到200mg/day或更高剂量持续治疗两周时，细胞色素P450同工酶3A (CYP3A) 和 2B6 (CYP2B6)代谢的自身诱导，导致全身清除率明显增加1.5-2倍。自身诱导也会导致奈韦拉平末期半衰期的减少，使其在血浆中从单一剂量的45小时减少到多剂量的25-30小时。 The multiple dose pharmacokinetics are charac-terized by metabolic autoinduct

14、ion of cytochrome P450 isozymes 3A (CYP3A) and 2B6 (CYP2B6) re-sulting in a 1.5- to 2-fold increase in nevirapine apparent systemic clearance as treatment continues from a single dose to 2 weeks of dosing with 200mg/day or higher 8. Autoinduction also results ina decrease in the nevirapine terminal

15、phase half-life in plasma from 45 h following a single dose to 25 30 h with multiple dosing.第10页，共45页，2022年，5月20日，2点14分，星期二凭借它的弱碱性和电离(pKa=2.8)，奈韦拉平的溶解度与PH相关。当PH值小于酸度系数时，奈韦拉平在缓冲溶液中的溶解度很高。随着PH值的升高，奈韦拉平自由碱在水中的溶解度会逐渐降低到0.1 mg/mL。尽管奈韦拉平口服容易吸收，但是尤其是服用50mg或是更高的剂量时，显示溶解度限制了吸收的速率（延迟了到达峰值的时间，加倍了峰值浓度），并且生物利用度也

16、有稍微的下降。 By virtue of its weakly basic character and ionization (pKa=2.8)nevirapine exhibits pH dependent solubility. At pH values less than the pKa nevirapine is highly soluble in aqueous buffer. At higher pH values nevirapine free-base solubility in water decreases asymptotically to approximately.

17、0.1 mg :mL. Although the drug appears to be readily absorbed orally, nevirapine, particularly at doses of 50 mg and higher, exhibits characteristics of solubil-ity rate-limited absorption (delayed time-to-peak,multiple peak concentrations) and a slight fall-off in bioavailability.第11页，共45页，2022年，5月2

18、0日，2点14分，星期二本文描述了两个研究的结果，这两个研究旨在表明奈韦拉平在人体内绝对和相对生物利用度的特征。在这两个研究中，将片剂和口服参比溶液作比较，确定是否是药物的剂型或是物理特性或是两者皆有，导致了奈韦拉平在吸收的速率或程度上有所不同。另外，由于长时间的药代动力学作用时期和假设在不同的静脉注射和口服剂量之间药代动力学的线性关系，我们利用解卷积法来更好的评价奈韦拉平的口服吸收特性。 This report describes the results of two studies aimed at characterizing the absolute and relative bioa

19、vailability of nevirapine in humans. In both studies a tablet formulation was compared to an oral reference solution to determine whether any differences in the rate or extent of nevirapine ab-sorption could be attributed to either the formula-tion or the physical characteristics of the drug, or bot

20、h. Additionally, because of the prolonged phar-macokinetic disposition phase and the assumption of pharmacokinetic linearity between different i.v.and oral doses, deconvolution was utilized to fur-ther assess the characteristics of nevirapine oral absorption.第12页，共45页，2022年，5月20日，2点14分，星期二实验对象和方法这两个

21、研究都是在Quintiles公司进行的（以前在Innovex公司），每一个研究用的纳入与排除的标准都一样。实验对象是不吸烟的健康的男性志愿者，年龄范围是从18岁到50岁。在研究过程中，志愿者不能服用其他药物，要戒除烟草制品、酒精、含咖啡因的饮料。要求志愿者的身高体重比在大城市人寿保险公司表定义的正常范围内占10%。志愿者是由相当好的健康状况决定的，它包括病史、外部身体检查和实验室检查（血液学、血液化学和尿液分析）。 Both studies were conducted at Quintiles, Inc. (for-merly Innovex, Inc.), Lenexa, KS, USA.

22、 The same inclusion and exclusion criteria were used for each study. Subjects were nonsmoking, healthy male vol-unteers, ranging in age from 18 to 50 years. No concomitant medications were allowed and subjects were required to abstain from tobacco products,alcohol or caffeine containing beverages du

23、ring the study. Subjects were required to have a height:weight ratio within 10% of normal as definedby the Metropolitan Life Insurance Company Ta-bles. Subjects were determined to be in reasonably good health based on medical history, physical ex-amination and a laboratory screen (hematology, blood

24、chemistry and urinalysis)第13页，共45页，2022年，5月20日，2点14分，星期二试验设计第一个研究通过服用片剂和参比溶液与静脉注射显示的(血药浓度时间)曲线下面积作比较，评估奈韦拉平的绝对生物利用度。这个实验根据一个公开的、单一剂量、随机的对12个健康的男性志愿者进行交叉实验。在进行药代动力学实验之前，我们在另一个实验中评估了12个志愿者（三个志愿者每剂量水平加上四倍的安慰剂）对三种静脉注射剂量（5、15和30mg）的奈韦拉平的安全性和耐药性。 The first study was designed to assess the absolute bioavai

25、lability of nevirapine from tablets and an oral reference solution by comparison of the extent of systemic exposure to the AUC from an intra-venous dose. The study was conducted according to an open label, single dose, randomized, crossover design in 12 healthy male volunteers. Before the pharmacoki

26、netic study, the safety and tolerance of three i.v. doses (5, 15 and 30 mg) of nevirapine were assessed in 12 subjects (three subjects per dose level plus four placebos) in a separate study. 第14页，共45页，2022年，5月20日，2点14分，星期二因为接受30mg剂量的志愿者有关节痛、头疼等症状，并且增加的肝功能检测表明，这些症状很可能由试验药物导致的，因此在目前的实验中，确定15mg是使用静脉注射的

27、最高耐受剂量。为了确定奈韦拉平的绝对生物利用度，十二个志愿者接收单一剂量的奈韦拉平，分别是静脉注射15mg，口服片剂50mg，口服溶液50mg。片剂用250mL的水送服，口服溶液（在1.5%的柠檬酸水溶液中每200mL含50mg奈韦拉平，PH3）用50mL水送服，静脉注射是通过手臂表面静脉注射37.5分钟（15 mg/18.75 mL）。不同的剂量由两周的清除时间分隔开。Because one of subjects receiving the 30 mg dose experience symptoms (e.g. arthralgia, headache) and increased li

28、ver function tests that were possibly attributed to the study drug, it was determined that 15 mg wasthe highest tolerable i.v. dose for use in the present study. For determination of absolute nevirapine bioavailability 12 subjects received single doses ofnevirapine as an intravenous injection (15mg)

29、, an oral tablet (50 mg), and an oral solution (50 mg).The tablet was administered with 250 mL of water,the oral solution (50 mg in 200 mL of 1.5% citric acid aqueous solution, pH B3) with 50 mL of water,and the i.v. injection was administered in a periph-eral arm vein as an i.v. infusion (15 mg :18

30、.75 mL)over 37.5 min. Doses were separated by a 2-week washout period.第15页，共45页，2022年，5月20日，2点14分，星期二在奈韦拉平的临床研究中进行的第二个实验，设计用来对200mg的片剂奈韦拉平与200mg的参比溶液的口服生物利用度进行比较，作为维乐命注册要求的一部分。这是一个在24个成年男性志愿者中进行的随机的、单一剂量的交叉实验。志愿者用250mL水送服一片200mg的奈韦拉平（在商业批量的条件下生产），50mL水送服参比溶液（每200mL3%柠檬酸水溶液中含奈韦拉平200mg，PH3）。24个志愿者中18个

31、完成了实验。不同的剂量由三周的清除时间分隔开。The second study, occurring later in the clinical development of nevirapine, was designed to assess the oral bioavailability of nevirapine 200 mg tablets compared to a 200 mg oral reference solution as part of the registration requirements for Viramune.This was a randomized, s

32、ingle dose, crossover study in 24 adult male volunteers. Subjects wereadministered nevirapine as a 200 mg tablet (manu-factured under commercial batch conditions) with 250 mL of water and as an oral reference solution(200 mg in 200 mL of 3% citric acid aqueous solu-tion, pH B3) with 50 mL of water.

33、Eighteen of the 24 enrolled subjects completed the study. Doses were separated by a 3-week washout period.第16页，共45页，2022年，5月20日，2点14分，星期二过程每种单一剂量都前一天晚上十点快速开始，服药后持续四小时，奈韦拉平大约在早上八点给药。在口服50mg剂量和静脉注射15mg剂量奈韦拉平五分钟之后开始计时，在0.17, 0.33, 0.5, 0.63, 0.75,0.83, 1, 1.25, 1.5, 1.75, 2, 3, 4, 8, 12, 16, 24, 48, 72

34、, 96和168小时的时候，抽取一系列用于药代动力学分析的静脉血样。 Each single dose was preceded by an overnight fastbeginning at 22:00 h and lasting until 4 h after dosing. Nevirapine was administered at approxi-mately 08:00 h. Serial sampling of venous blood(5 mL) for pharmacokinetic analysis was done 5 min before (0 h) and at 0

35、.17, 0.33, 0.5, 0.63, 0.75, 0.83, 1, 1.25, 1.5, 1.75, 2, 3, 4, 8, 12, 16, 24, 48, 72, 96and 168 h following the 50 mg oral and 15 mg i.v.doses. 第17页，共45页，2022年，5月20日，2点14分，星期二在第二个实验中，在200mg剂量服用之前和服用之后的0.5, 1, 2, 4, 6, 8, 12, 16, 24, 48,72, 96, 120, 144 和168小时收集血浆样品。血液被收集在肝素真空管中，然后在相对离心力10000的作用下离心十分

36、钟。血浆被收集起来后转移到螺旋盖冻存管储存在-20，然后用色谱法对奈韦拉平进行含量测定。In the second study plasma samples were collected prior to and 0.5, 1, 2, 4, 6, 8, 12, 16, 24, 48, 72, 96, 120, 144 and 168 h following the 200 mg doses. Blood was collected in heparinized evacuated tubes, which were then centrifuged at 10 000g for 10 min.

37、 Aliquots of plasma were collected, transferred to screw-top cryotubes and stored at 20C until they were chromatographically assayed for nevirapine at Boehringer Ingelheim Pharmaceuticals, Inc.第18页，共45页，2022年，5月20日，2点14分，星期二分析方法使用高效液相色谱法和紫外检测法(=280 nm)测定奈韦拉平（相对分子质量266.3）在人体血浆中的含量。定量检测的下限是25 ng/mL，上限

38、是10000 ng/mL。通过每种分析方法对样品进行分析表明，这种含量检测方法的精确度（%变异系数）和准确度（%偏差）在15%以内。Nevirapine (MW 266.3) was quantitated in human plasma using a high performance liquid chromato-graphic (HPLC) assay with ultraviolet (UV) detection (=280 nm) 13. The assay limits of quantitation were 25 ng :mL and 10 000 ng:mL.Quality

39、 control samples analysed with each analyti-cal run demonstrated that the assay had a precision(% coefficient of variation (C.V.) and an accuracy(% bias) within 15%.第19页，共45页，2022年，5月20日，2点14分，星期二药代动力学分析 对于口服数据，药代动力学分析是利用数据分析软件SAS6.22版进行的。最高观察浓度值和相关的时间点被定义为峰浓度（Cmax）和达峰时间（Tmax）。检测血药浓度-时间数据的半对数曲线图被用于确

40、定合适的初始数据点（24h），用来推测最终的消除速率常数(z)。可以利用线性梯形积分法计算奈韦拉平血浆浓度-时间曲线下面的从时间0到最终可计量的浓度时间的区域的面积（AUCt）。 For the oral data pharmacokinetic analyses were performed using the statistical analysis software program SASVersion 6.11 (SAS Institute, Cary,NC). The highest observable concentration and as-sociated time poin

41、t were defined as the peak concentration ( Cmax) and time-to-peak concentration(Tmax). Semilogarithmic plots of the plasma concentration time data were examined to determine the appropriate initial data point (24 h) for estimating the terminal elimination rate constant (z). The areas under the nevir

42、apine plasma concentration time curve from time zero to the last quantifiable concen-tration (AUCt) were calculated using the linear trapezoidal rule. 第20页，共45页，2022年，5月20日，2点14分，星期二总的AUC可以看成是AUCT和Ct/z，这里Ct代表最终可计量浓度。另外，还计算了奈韦拉平的一些药代动力学参数表观全身清除率(Cl/F)、末期半衰期（t1/2）、平均停留时间（MRT）、表观分布容积（Vss/F）。绝对生物利用度（F）可

43、以这样计算，标准化给药的AUCoral/AUCi.v.的比率。相对生物利用度（Frel）可以当成相同给药剂量的AUC片剂/AUC溶液的比率来计算。Total AUC was calculated as the sum of AUCTand Ct/z, where Ct represents the last quantifiable concentration. Additionally, the pharmacokinetic parameters of nevirapine apparent systemic clearance(Cl/F ), terminal-phase half-li

44、fe (t1/2),mean residence time (MRT), apparent volume of distribution (Vss/F ) were calculated . Absolute bioavailability (F ) was calculated as the dose-normalized ratio of AUCoral divided by AUCi.v. Relative bioavailability (Frel) was calculated as the same dose ratio of AUC tablet divided by AUC s

45、oln第21页，共45页，2022年，5月20日，2点14分，星期二血管内给药的药代动力学的特点是通过非线性回归分析（SAS NLIN）把观察的i.v.浓度数据拟合成一个零级吸收和一级消除的二室模型：The pharmacokinetics of the intravenous dose were characterized by fitting a two-compartmentmodel with a zero-order input and first-order elimination to the observed i.v. concentration data using nonl

46、inear regression analysis (SAS NLIN)：第22页，共45页，2022年，5月20日，2点14分，星期二这里公式(1)中C(t)表示血浆浓度，Ai和i分别表示二室模型的系数和速度常数，在注射时等于时间(=t），在注射之后等于注射时间（=tinf）。非线性回归分析用到一个浓度的倒数的加权函数（1/Yi1.4)，这里i是指第i个受试对象的估计浓度。拟合度是通过求加权平方和的最小值来评价的，同时还要检查预测值和残差图的离散度。where C (t ) in Equation (1) represents the plasma concentration, Ai and

47、 ai represent the coefficients and rate constants for a two-compartment model, respectively, and equals time during the infusion(=t ) and equals the infusion time following the end of infusion (=tinf). An inverse concentration weighting function (1/Yi1.4) was used for the nonlinear regression analys

48、is where i is the predicted concentration for the ith subject. Goodness of fit was evaluated by minimizing the weighted sums of squares and by examining the randomness of scatter of the predicted values and residual plots.第23页，共45页，2022年，5月20日，2点14分，星期二我们进行了成对的口服和静脉注射数据的数值解卷积来评价奈韦拉平随着时间吸收的速度和积累的程度。描

49、述任意药物给药和导致的浓度分布曲线图之间的关系的表达由公式（2）解卷积积分给出。 Numerical deconvolution of the paired oral and intravenous data was performed to assess the rate and cumulative extent of nevirapine absorption over time. The expression that describes the rela-tionship between drug administration and the re-sulting concentra

50、tion profile for any drug is given by the convolution integral in Equation (2)第24页，共45页，2022年，5月20日，2点14分，星期二这里的C（t）表示观察到的药物浓度，f(t)表示吸收速率，C(t)表示单位脉冲响应，符号“*”表示卷积。假设线性药代动力学和时间变量C(t)代表瞬间注入药物后的药物的药动学处置，C(t)是从静注浓度-时间数据拟合公式（1）得到的静脉注射药动学参数建立的： where C (t ) represents the observed drug concentration, f (t )

51、 the input rate, c (t ) is the unit impulse response, and the symbol * denotes convolution. Assuming linear pharmacokinetics and time invariance c (t ) represents the pharmacokinetic disposition of the drug following instantaneous input, and was constructed from the i.v. pharmacokinetic parameters d

52、erived by fitting Equation (1) to the i.v.concentration time data:第25页，共45页，2022年，5月20日，2点14分，星期二然后利用PC软件程序PCDCON提供的标准数值解卷积算法以观察的口服浓度数据（C(t)）评估口服吸收速率（f(t)）。The rate of oral absorption ( f (t ) was then assessed on the observed oral concentration data (C (t ) using standard numerical deconvolution al

53、gorithms pro-vided with the PC software program PCDCON 18.第26页，共45页，2022年，5月20日，2点14分，星期二数据分析为了评价相对生物利用度，我们对AUC和Cmax的log转化比值进行了误差分析（ANOVA），分析时利用了SAS6.11中的GLM程序。模型考虑了下列误差来源：顺序、嵌入顺序的志愿者、周期和治疗。我们检验了AUC和Cmax的两个片面假设，适用于建立的90%置信区间的片剂和口服参比溶液之间的比率。For purposes of evaluating relative bioavailability,an analy

54、sis of variance (ANOVA) was performed on the log-transformed ratios for AUC and Cmax using the GLM procedure in SAS 6.11. The following sources of variation were accounted for in the model: sequence, subjects nested within sequence, period, and treatment. The two one-sided hypothesis (p=0.05) was te

55、sted for AUC and for Cmax where applicable by constructing the 90% confidence intervals for the ratio between the tablet formulations and the oral reference solution.第27页，共45页，2022年，5月20日，2点14分，星期二结果实验对象参加绝对生物利用度实验的12名健康成年男性志愿者没有事故全部完成了实验。志愿者的平均年龄是29.8岁（范围是20-49岁）。他们的平均体重是80.6千克（范围是千克）。没有严重的不良反应的报道，

56、在生命特征和实验试验中也没有重大的临床变化。 All 12 healthy adult men enrolled in the absolute bioavailability study completed the study without incident. Subjects mean age was 29.8 years (range20 49 years). Their mean body weight was 80.6 kg(range 67.7 96.8 kg). There were no reported seri-ous adverse events and no clin

57、ically important changes in vital signs or laboratory tests. 第28页，共45页，2022年，5月20日，2点14分，星期二有24个成年男性志愿者参加了相对生物利用度的实验。他们的平均年龄和体重分别是26.9岁（范围是18-43岁）和78.5千克（范围是千克）。十八个志愿者完成了实验。在中断实验的六个人中，有五个是因为实验时间太长退出，一个是因为肝功检查升高而停止。其他人都有很好的耐受性，并且没有严重的不良反应。For the relative bioavailability study, 24 adult men were enro

58、lled. Their mean age and weight were 26.9 years (range 18 43 years) and 78.5 kg (range 58.8 95.5 kg), respectively. Eighteen subjects completed the study. Of the six subjects who discontinued the study, five dropped out due to the length of the study and one was discontinued due to an elevation in h

59、is liver function tests. Otherwise, the treatments were well tolerated and there were no reported serious adverse events第29页，共45页，2022年，5月20日，2点14分，星期二奈韦拉平的药代动力学和生物利用度血浆中奈韦拉平静脉注射和口服剂量的浓度-时间曲线图见图2。静脉注射后，平均药代动力学的各项参数见表1。经过37.5分钟的注射后，奈韦拉平的血浆浓度呈双指数下降。平均停留时间（81.4h）、分布和末期半衰期(0.38 h对52.8 h)表明奈韦拉平在人体内有一个持续很

60、久的药代动力学作用时期。奈韦拉平的全身清除率(1.41 L/h)与报道的奈韦拉平作为单一剂量服用的其它单剂量的实验一致。 The plasma concentration time profiles of nevirapine i.v. and oral dosing are shown in Figure 2. The mean pharmacokinetic disposition parameters afteri.v. dosing are presented in Table 1. Following the 37.5 min infusion nevirapine plasma c