Evaluation of the bioequivalence and pharmacokinetics of two tablet formulations of isosorbide-5-mononitrate after single oral administration in healthy volunteers

The pharmacokinetic parameters of two oral formulations of 20 mg tablets of isosorbide-5-mononitrate (CAS 16051-77-7, Dilavenil as test and another commercially available preparation as reference) were compared in an open-label, randomized, single oral dose, two-period cross-over design in 20 healthy volunteers under fasting conditions. Plasma concentrations of isosorbide-5-mononitrate were measured by a validated gas chromatographic assay. The parametric 90% confidence intervals of the geometric mean values of the test/reference ratios were 101.2% to 108.5% (point estimate: 104.7%) for AUC0-variation of, 101.6% to 110.7% (point estimate: 106.2%) for AUC0-t, and 98.1% to 115.5% (point estimate: 106.1%) for Cmax, within the acceptance criteria for bioequivalence (80%-125%). Tmax values were analyzed by the nonparametric Wilcoxon test and the difference was not statistically significant. Therefore, it is concluded that the test and reference isosorbide-5-mononitrate formulations are bioequivalent for both the extent and the rate of absorption.     

Evaluation of the bioequivalence of two tablet formulations of enalapril/hydrochlorothiazide after single oral administration to healthy volunteers

The pharmacokinetic parameters of two oral formulations of 20/12.5 mg tablets of enalapril/hydrochlorothiazide (CAS 75847-73-3 and CAS 58-93-5, respectively; Penopril as test and another commercially available preparation as reference) were compared in an open-label randomized single oral dose two-period cross-over design to 24 healthy volunteers under fasting conditions. Plasma concentrations of enalaprilat (CAS 76420-72-9), the pharmacologically active metabolite of enalapril, and hydrochlorothiazide were determined by a validated GC/MS and HPLC assay, respectively. Serial blood samples were collected prior to each administration and at 19 timepoints within 36 h after dosing. The parametric 90% confidence intervals of the geometric mean values of the test/reference ratios for enalaprilat were 99.3% to 118.9% (point estimate: 108.7%) for AUC(0-infinity), 97.3% to 116.9% (point estimate: 106.7%) for AUC(0-t), and 92.5% to 113.0% (point estimate: 102.3%) for Cmax, and for hydrochlorothiazide 92.3% to 105.1% (point estimate: 98.5%) for AUC(0-infinity), 92.7% to 105.4% (point estimate: 98.9%) for AUC(0-t), and 97.6% to 115.3% (point estimate: 106.0%) for Cmax, within the acceptance criteria for bioequivalence (80%-125%). Tmax values were analyzed by the nonparametric Wilcoxon test and the difference was not statistically significant. Therefore, it is concluded that the test and reference enalapril/hydrochlorothiazide formulations are bioequivalent for both the extent and the rate of absorption.     

Comparison of two microemulsion of cyclosporine A in healthy volunteers

This study evaluated the bioequivalence of a new Cyclosporine A microemulsion formulation in comparison to the reference market standard. Twenty-four adult healthy volunteers were randomised to receive the two Cyclosporin A microemulsion formulations, at a dose of 2.5 mg/kg, according to a cross-over design. Blood samples were taken before drug administration and at 12 points within 24 hours. Cyclosporine A whole blood concentrations were determined by HPLC. The pharmacokinetic parameters AUC0-t and AUC0-infinity were calculated by the trapezoidal rule, Cmax and Tmax were obtained directly from blood data. AUCs and Cmax were tested for bioequivalence after log transformation of data, differences for Tmax were evaluated by the rank test of Wilcoxon for paired data. The 90% confidence interval ratio between tested/reference drug was 0.98 for AUC0-t, 0.96 for AUC0-infinity and 1.01 for Cmax. All of them were within the range of bioequivalence. Tmax was 1.60 +/- 0.44 hours after test drug and 1.67 +/- 0.48 after reference drug (p = 0.27, Wilcoxon test). According to these results the two Cyclosporine A microemulsion formulations can be considered bioequivalent.     

盐酸利托君片在中国健康人体的生物等效性

目的评价2种国产盐酸利托君片在中国健康人体的生物等效性。方法22名健康女性受试者随机交叉单剂量口服盐酸利托君片试验药物或对照药物,各10 mg。用高效液相色谱-串联质谱法测定血浆中盐酸利托君浓度;用DAS2.0软件计算药代动力学参数,并对2种药物进行生物等效性评价。结果试验药物和对照药物的主要药代动力学参数:Cmax分别为(5.71±1.83)和(5.61±2.03)ng.mL-1;Tmax分别为(0.54±0.45)和(0.46±0.24)h;t1/2分别为(3.64±3.99)和(4.25±4.02)h;AUC0-t分别为(12.31±5.20)和(12.01±5.42)h.ng.mL-1。AUC0-t、AUC0-∞、Cmax的90%可信区间分别为95.8%～111.6%、92.3%～118.9%和95.4%～108.2%。试验药物相对于对照药物的生物利用度F为(105.3±19.96)%。结论试验药物和对照药物生物等效。     

Bioequivalence study of 2 orodispersible formulations of ondansetron 8 mg in healthy volunteers

This study was designed to compare the rate and extent of absorption of 2 oral formulations of ondansetron (CAS 99614-02-5) 8?mg orodispersible tablets in healthy volunteers. 22 subjects were administered ondansetron orodispersible tablets of test and reference formulation in a single-dose, 2-period, 2-sequence, fasting, open-label, crossover and randomised study. Plasma concentrations were determined by LC/MS/MS. Log-transformed AUCs and Cmax values were tested for bioequivalence based on the ratios of the geometric means (test/reference). Tmax was analysed nonparametrically. The 90% confidence intervals of the geometric mean values for the test/reference ratios for AUC0-t and Cmax were within the bioequivalence acceptance range of 80-125%. According to the European Guideline [1] it may be therefore concluded that test formulation of ondansetron 8?mg orodispersible tablet is bioequivalent to the reference formulation.     

盐酸二甲双胍片在中国健康人体的生物等效性

目的评价2种国产盐酸二甲双胍片(口服降糖药)在中国健康人体的生物等效性。方法 20名健康男性受试者随机交叉单剂量口服盐酸二甲双胍片试验药物和对照药物,各1.0 g。用高效液相色谱法测定血浆中盐酸二甲双胍的浓度,用DAS 2.0软件计算药代动力学参数,并对2种药物进行生物等效性评价。结果试验药物和对照药物的主要药代动力学参数如下:Cmax为(2.83±0.53),(2.57±0.57)mg.L-1;Tmax为(1.55±0.39),(1.63±0.36)h;t1/2为(3.70±1.76),(3.36±0.72)h;AUC0-24为(10.20±1.95),(9.71±2.56)mg.h.L-1。AUC0-24、AUC0-∞、Cmax的90%可信区间分别为99.1%～114.6%、99.1%～113.8%和100.6%～110.4%。试验药物相对于对照药物的生物利用度F为(108.3±20.5)%。结论试验药物和对照药物生物等效。     

Evaluation of the bioequivalence and pharmacokinetics of two formulations of rizatriptan after single oral administration in healthy volunteers

The pharmacokinetic parameters of two oral formulations of rizatriptan (CAS 144034-80-0, a capsule preparation as test and rizatriptan tablet as reference), given at a single dose of 10 mg each, were compared in an open-label, randomized, single oral dose, two-period cross-over design in 20 healthy volunteers under fasting conditions. Plasma concentrations of rizatriptan were measured by a validated HPLC assay. The parametric 90% confidence intervals of the geometric mean values of the test/reference ratios were 91.9% to 101.9% (point estimate: 97.3%) for AUC(0-infinity), 93.0% to 102.2% (point estimate: 96.5%) for AUC(0-t), 90.1% to 100.0% (point estimate: 95.4%) for Cmax, being within the acceptance criteria for bioequivalence (80%-125%). Tmax values were analyzed by the nonparametric Wilcoxon test and the difference was not statistically significant. Therefore, it is concluded that the test and reference rizatriptan formulations are bioequivalent with regard to both the extent and the rate of absorption.     

Comparative bioavailability of two brands of atenolol 100 mg tablets (Tensotin and Tenormin) in healthy human volunteers

A bioequivalence study of two oral formulations of 100 mg atenolol was carried out in 24 healthy volunteers following a single dose, two-sequence, cross-over randomized design at the International Pharmaceutical Research Centre (IPRC), as a joint venture with Al-Mowasah Hospital, Amman, Jordan. The two formulations were Tensotin (Julphar, UAE) as test and Tenormin (Zeneca, UK) as reference product. Both test and reference tablets were administered with 240 ml of water to each subject after an overnight fast on 2 treatment days separated by a 1 week washout period. After dosing, serial blood samples were collected for a period of 36 h. Whole blood was analysed for atenolol by a sensitive, reproducible and accurate HPLC method with fluorescence detection capable of detecting atenolol in the range of 20-1600 ng/ml with a limit of quantitation of 20 ng/ml. Various pharmacokinetic parameters including AUC0-t, AUC0-proportional to), Cmax, Tmax, T1/2 and lambdaZ were determined from blood concentrations of both formulations and found to be in good agreement with reported values. AUC0-t, AUC0-proportional to), and Cmax were tested for bioequivalence after log-transformation of data using ANOVA and 90% confidence interval and were found within the acceptable range of 80%-125%. Based on these statistical inferences, it was concluded that Tensotin is bioequivalent to Tenormin.     

Bioequivalence of two oral formulations of triflusal capsules in healthy volunteers

Triflusal (CAS 322-79-2) is an antiplatelet agent related to salicylates used in several European and Latin American countries in the treatment of cardiovascular diseases. The aim of this paper was to evaluate the bioequivalence of triflusal derived from two preparations using both parent drug and metabolite pharmacokinetic data. The bioavailabolity was measured in 24 healthy male Caucasian volunteers following a single oral dose (600 mg) of the test or reference products in the fasting state. Blood samples were collected for 120 h. Plasma concentrations of triflusal and its metabolite 3-hydroxy-4-trifluoromethylbenzoic acid (HTB) were analyzed by high-performance liquid chromatography with UV and fluorescence detection, respectively. The non-compartmental method was used for pharmacokinetic analysis. Log-transformed Cmax, AUC0-t and AUC0-infinity were tested for bioequivalence using ANOVA and Schuirmann's two-one sided t-test. Tmax was analyzed by nonparametric pharmacokinetic parameters of triflusal and HTB derived from the two formulations were nearly consistent with previous observations. Triflusal parameters derived from the test and reference drug were as follows: Cmax (16.85 +/- 11.41 vs 14.48 +/- 7.22 mg/l), AUC0-t (18.43 +/- 10.91 vs 16.22 +/- 7.58 mg/l per hour), Tmax (1 range 0.25-2h vs 0.875 range 0.25-1.5 h), and t(1/2) (0.49 +/- 00.27 vs 0.76 +/- 0.64). HTB parameters after test and reference formulation administration were as follows: Cmax (68.13 +/- 23.05 vs 65.51 +/- 19.44 mg/l), AUC0-t (2748.18 +/- 971.91 vs 2877.97 +/- 881.2 h x mg/l), AUC0-infinity (3350.15 +/- 1182.62 vs 3372.49 +/- 1110.35 h x mg/l), Tmax (2 range 1-10 h vs 2 range 0.75-12 h), and t(1/2) (42.19 +/- 7.82 vs 43.13 +/- 6.56 h). 90% of confidence intervals for the test/reference ratio of Cmax AUC0-t and AUC0-infinity derived from both triflusal and HTB were found within the range of 80%-125% acceptable for bioequivalence. No significant difference was found between the Tmax values for triflusal and HTB. It was concluded that the two preparations are bioequivalent and may be prescribed interchangeably.     

阿德福韦酯胶囊人体生物等效性研究

目的：评价国产阿德福韦酯胶囊与进口阿德福韦酯片（贺维力）的生物等效性。方法：20位健康男性志愿者随机交叉口服单剂量受试制剂（阿德福韦酯胶囊）和参比制剂（贺维力）;用LC-MS/MS法,分别测定药物血浆浓度,DAS2.0计算药代动力学参数,评价生物等效性。结果：受试制剂和参比制剂的主要药代动力学参数,AUC0-t分别为（207.92±45.80）ng.h-1.mL-1和（221.25±54.18）ng.h-1.mL-1,AUC0-∞分别为（217.16±45.93）ng.h-1.mL-1和（230.63±53.80）ng.h-1.mL-1,Cmax分别为（17.61±3.21）ng.mL-1和（19.76±4.64）ng.mL-1,Tmax分别为（1.70±0.64）h和（1.33±0.61）h,t1/2分别为（8.10±1.12）h和（8.11±1.34）h。AUC0-t、AUC0-∞和Cmax90%可信区间分别为89.8%～99.2%、90.2%～98.9%和82.4%～98.0%;相对生物利用度为（95.1±11.9）%（以AUC0-t计）、（95.1±11.1）%（以AUC0-∞计）。结论：2种制剂具有生物等效性。     

Bioequivalence assessment of Lovrak (Julphar, UAE) compared with Zovirax (Glaxo Wellcome, UK)--Two brands of Acyclovir--in healthy human volunteers

Two studies were performed to assess the relative bioavailability of Lovrak (Julphar, UAE) compared with Zovirax (Glaxo Wellcome, UK) at the International Pharmaceutical Research Center (IPRC), Amman, Jordan. One study involved acyclovir tablets and the other acyclovir suspension. Each study enrolled 24 volunteers and in both studies, after an overnight fasting, the two brands of acyclovir were administered as a single dose on 2 treatment days separated by 1 week washout period. After dosing, serial blood samples were collected for a period of 16 h. Plasma harvested from blood, was analysed for acyclovir by an HPLC method with UV detection. Various pharmacokinetic parameters including AUC0-t, AUC0-infinity, Cmax, Tmax, T1/2 and Kelm were determined from plasma concentrations for both formulations and found to be in good agreement with the reported values. AUC0-t, AUC(0-proportional to), and Cmax were tested for bioequivalence after log-transformation of data. No significant difference was found based on ANOVA; 90% confidence intervals for the test/reference ratio of these parameters were found within the bioequivalence acceptance range 80%-125%. Based on these statistical inferences it was concluded that a Lovrak tablet is bioequivalent to a Zovirax tablet and that Lovrak suspension is bioequivalent to Zovirax suspension.     

Bioequivalence of two oral ciprofloxacin tablets formulations

The relative bioavailability of a new 750 mg tablet formulation of ciprofloxacin (test formulation supplied by Dr. August Wolff GmbH and Co., Germany) was compared with that of Ciprobay tablets 750 mg (reference formulation from Bayer Vital GmbH and Co., Germany). Twenty-four healthy volunteers (12 male and 12 female) were included in this single-dose, 2-sequence, crossover randomized study. Blood samples were obtained prior to dosing and at 0.5, 0.75, 1, 1.5, 2, 3, 4, 6, 8, 10, 12, 18, 24 and 30 hours after drug administration. Plasma concentrations of ciprofloxacin were determined by HPLC. No differences were found when the in vitro dissolution profiles of both formulations were compared. The pharmacokinetic parameters AUC(0-t), AUC(0-infinity), Cmax and Cmax/AUC(0-infinity) were tested for bioequivalence after log-transformation of data, and ratios of tmax were evaluated nonparametrically. The parametric analysis revealed the following mean values for the test/reference ratios (90% standard confidence intervals in parenthesis (ln-transformed data): 1.01 (0.95-1.07) for AUC(0-t), 0.99 (0.93-1.05) for AUC(0-infinity), 1.05 (0.97-1.14) for Cmax and 1.06 (0.97-1.15) for Cmax/AUC(0-infinity). The nonparametric confidence interval for tmax was 0.77-1.15. All parameters showed bioequivalence between both formulations as their confidence intervals were within the bioequivalence acceptable range of 0.80-1.25 limits; the 90% confidence interval for tmax slightly exceeded limits of bioequivalence. We conclude that both formulations show bioequivalence for both the rate and the extent of absorption.     

国产来曲唑片应用于乳腺癌内分泌治疗的 生物等效性研究

目的：研究国产来曲唑片在人体内的生物利用度,并与参比制剂比较,评价其生物等效性。方法20名健康男性志愿者随机口服国产来曲唑片2.5 mg（受试制剂）或进口来曲唑片2.5 mg（参比制剂）后,采用高效液相色谱法测定不同时刻血浆中来曲唑的浓度,用WinNonlin5.2.1数据统计软件计算药代动力学参数,并评价其生物等效性。结果单次口服国产来曲唑片2.5 mg或参比制剂2.5 mg后,药代动力学参数分别为：受试制剂的t1/2：（43.91±12.68）h、Cmax：（30.94±7.05）ng·mL^-1、Tmax：（2.13±2.59）h、AUC0-t：（1478±421）ng·h·mL^-1;参比制剂的t1/2：（40.49±12.23）h、Cmax：（27.93±5.41）ng mL^-1、Tmax：（2.20±1.72）h、AUC0-t：1503±396 ng·h·mL^-1。经方差分析、双单侧t检验和[1-2α]％置信区间法进行生物等效性评价,其中Tmax采用非参数检验法,结果表明受试制剂与参比制剂间的各药动学参数的差异无统计学意义（P〉0.05）。结论国产来曲唑片与进口来曲唑片在人体内具有生物等效性。     

左旋多巴片在健康人体的生物等效性

目的评价2种左旋多巴片(抗震颤麻痹药)在健康人体内的生物等效性。方法 18名健康男性受试者随机交叉给药,分别单次口服左旋多巴片的试验药物或对照药物250 mg,用高效液相色谱法测定左旋多巴的血药浓度,计算2种药物的药代动力学参数,并评价其生物等效性。结果口服左旋多巴片试验药物及对照药物的主要药代动力学参数:t1/2分别为(1.06±0.31),(1.02±0.40)h;Tmax分别为(0.53±0.39),(0.54±0.37)h;Cmax分别为(1.69±0.66),(1.61±0.68)μg.mL-1;AUC0-t分别为(2.00±0.64),(1.85±0.50)μg.h.mL-1;AUC0-∞分别为(2.10±0.64),(1.95±0.55)μg.h.mL-1。试验药物相对于对照药物的平均相对生物利用度F值:AUC0-t为(110.9±33.1)%,AUC0-∞为(111.1±32.4)%。结论 2种左旋多巴片生物等效。     

Comparative bioavailability of two immediate-release tablets of lisinopril/hydrochlorothiazide in healthy volunteers

AIM: Two formulations of lisinopril/hydrochlorothiazide (20 mg/12.5 mg) were evaluated for bioequivalence after single dosing in healthy volunteers. METHODS: The study was conducted according to an open, randomized, 2-period crossover design with a 2-week washout interval between doses. Twenty-four volunteers participated and all completed the study successfully. Lisinopril and hydrochlorothiazide were determined in plasma by HPLC. The pharmacokinetic parameters AUC(0-t), AUC(0-infinity), Cmax and Cmax/AUC(0-infinity) were tested for bioequivalence after logarithmic transformation of data and ratios of tmax were evaluated non-parametrically. RESULTS: For lisinopril, the parametric analysis revealed the following test/reference ratios and their confidence intervals (90% CI): 1.01 (0.84-1.22) for AUC(0-t), 0.98 (0.81-1.19) for AUC(0-infinity), 1.02 (0.83-1.25) for Cmax and 1.03 (0.99-1.08) for Cmax/AUC(0-infinity). The 90% CI for tmax was 0.94-1.07. All parameters showed bioequivalence between both formulations. As for hydrochlorothiazide, test/reference ratios and their confidence intervals (90% CI) were: 1.05 (0.95-1.17), 1.02 (0.93-1.12) for AUC(0-infinity), 0.99 (0.89-1.07) for Cmax and 0.97 (0.90-1.04) for Cmax/AUC(0-infinity). The 90% CI for tmax was 1.00-1.41. All parameters showed bioequivalence between both formulations except for tmax. A discrete fall in both systolic (SBP) and diastolic (DBP) blood pressure was observed after drug administration. The time course of both parameters was similar for the 2 formulations. Heart rates also followed a similar time profile. CONCLUSIONS: The bioequivalence of the 2 formulations of lisinopril/hydrochlorothiazide was demonstrated.     

Bioequivalence of two tablet formulations of atenolol after single oral administration in healthy volunteers

The pharmacokinetic parameters of two oral formulations of 100 mg tablets of atenolol (CAS 29122-68-7; Azectol as test and another commercially available preparation as reference) were compared in an open-label, randomized, single oral dose, two-period cross-over design to 17 healthy volunteers under fasting conditions. Serial blood samples were collected prior to each administration and at 17 points within 36 h after dosing. Plasma concentrations of atenolol were measured by a validated HPLC assay with fluorometric detection. The parametric 90% confidence intervals of the geometric mean values of the test/reference ratios were 94.4% to 112.9% (point estimate: 103%) for AUC0-infinity, 93.7% to 112.8% (point estimate: 103%) for AUC0-36, and 88.3% to 112.1% (point estimate: 100%) for Cmax, within the acceptance criteria for bioequivalence (80%-125%). Tmax values were analyzed by the nonparametric Wilcoxon test and the difference was not statistically significant. Therefore, it is concluded that the test and reference atenolol formulations are bioequivalent for both the extent and the rate of absorption.     

多剂量口服硝苯地平缓释片的药动学及生物等效性研究

目的研究多剂量口服硝苯地平缓释片在人体内的药动学特点和两种硝苯地平缓释片的生物等效性.方法22名健康男性志愿者采用双周期交叉、自身对照试验设计.以尼群地平为内标,采用高效液相色谱-大气压化学源-质谱联用(HPLC-MS)的方法,测定人血浆中硝苯地平的浓度.将22名受试者的经时血药浓度录入DAS(ver 1.0)程序,得到药代动力学参数,并进行统计分析和生物等效性评价.结果多剂量口服 20 mg×7 d 受试和参比制剂后血浆中硝苯地平的Cmax分别为 52.5±27.4、54.0±31.2 ng·ml-1,Cmin分别为 5.4±4.1、6.2±5.9 ng·ml-1,Cav分别为 16.8±9.2、19.3±12.4 ng·ml-1,Tmax分别为 3.7±0.9、4.1±1.1 h,t1/2分别为 8.9±4.9、8.5±3.1 h,AUC0-τ分别为 403.4±221.0、461.9±296.6 ng·h·ml-1,AUC0-36h分别为 444.4±256.1、503.1±330.9 ng·h·ml-1,AUC0-∞分别为 482.1±268.9、542.3±348.4 ng·h·ml-1 ,DF分别为(299.8±117.7)%、(279.2±97.5)%.Tmax进行非参数秩和检验,Cmax、Cmin、Cav、DF、AUC0-τ、AUC0-36h、AUC0-∞经对数转换后做方差分析,并经双向单侧t检验,两制剂的Tmax、Cmax、Cmin、Cav、DF、AUC0-τ、AUC0-36h、AUC0-∞均无显著性差异(P＞0.05),受试制剂的Cav、DF、AUC0-36h、AUC0-τ、AUC0-∞的90%可信限落在参比制剂的80%～125%范围内;Cmax、Cmin的90%可信限落在参比制剂的70%～143%范围内.两种制剂的相对生物利用度为(100.6±38.6)%(AUC0-36h,T/AUC0-36h,R×100%).结论两种制剂具有生物等效性.     

Bioequivalence study of two limaprost alfadex 5 microg tablets in healthy subjects: moisture-resistant tablet (dextran formulation) versus standard tablet (lactose formulation)

OBJECTIVE: A study was conducted to assess the bioequivalence of two limaprost alfadex 5 microg tablets, a moisture-resistant tablet (dextran formulation) and a standard tablet (lactose formulation). MATERIALS AND METHODS: The clinical investigation was designed as a randomized, open-labeled, two-part, two-treatment, two-period crossover study, in 120 healthy male volunteers. One tablet of either formulation was administered with 200 ml of water after 10-hour overnight fast. After dosing, serial blood samples were collected for a period of 6 hours. Plasma harvested from blood was analyzed for limaprost by a validated LC/MS/MS method. The peak plasma concentration (Cmax) values and time associated with the maximal concentration (tmax) were obtained from the observed data. The elimination rate constant (lambda z) was obtained as the slope of the linear regression of the log-transformed concentration values vs. time data in the terminal phase, and the elimination half-life (t1/2) was calculated as 0.693/lambda z. The area under the curve to the last measurable point (AUC0-t) was estimated by the linear trapezoidal rule. The analysis of variance (ANOVA) was carried out using log-transformed AUC0-t, AUC0-A yen and Cmax and untransformed tmax, and 90% confidence intervals for AUC0-t and Cmax were calculated. If the 90% confidence intervals (CI) for both AUC0-t and Cmax fell fully within the interval 80 - 125%, the bioequivalence of the two formulations was established. RESULTS: The means of AUC0-t were 0.779 vs. 0.754 pg x h/ml (test vs. reference), and the means of the Cmax were 1.26 vs. 1.12 pg/ml (test vs. reference). The geometric mean ratios of the test formulation to reference formulation for AUC0-t and Cmax were 104.0 and 112.4%, respectively, and the 90% CI for AUC0-t and Cmax were 100.7 - 107.4% and 105.6 - 119.6%, respectively. Both 90% CI for AUC0-t and Cmax fell within the Ministry of Health, Labour and Welfare of Japan accepted bioequivalence range of 80 - 125%. CONCLUSIONS: Based on the results, the moisture-resistant tablet was determined to be bioequivalent to the standard tablet.     

Bioequivalence Study of 2 Orodispersible Formulations of Zolmitriptan 5 mg in Healthy Volunteers

A bioequivalence study of 2 zolmitriptan (CAS 139264-17-8) orodispersible tablet formulations was carried out in 26 healthy volunteers according to an open label, randomized, 2-period, 2-sequence, crossover, single dose and fasting conditions design. The test and reference formulations were administered in 2 treatment days, separated by a washout period of 7 days. Plasma concentrations of zolmitriptan and its active metabolite (N-desmethyl-zolmitriptan) were obtained by LC/MS/MS method. Log-transformed AUCs and Cmax values were tested for bioequivalence based on the ratios of the geometric means (test/reference). Tmax was analysed nonparametrically. The 90% confidence intervals of the geometric mean values for the test/reference ratios for AUC0-t and Cmax were within the bioequivalence acceptance range of 80-125%. According to the European Guideline 1 it may be therefore concluded that test formulation of zolmitriptan 5?mg orodispersible tablet is bioequivalent to the reference formulation.     

Bioequivalence and pharmacokinetic comparison of 3 metformin extended/sustained release tablets in healthy Indian male volunteers

This study was undertaken to compare the bioavailability and pharmacokinetic properties of 3 marketed product of metformin (CAS 1115-70-4) extended/sustained release formulation in Indian male volunteers. Study was designed as an open-label, randomized, 3-treatment, single-dose, crossover, bioavailability study comparing 3 marketed brands of 500?mg metformin extended/sustained release tablets in 18 healthy human male volunteers under fed condition. A single oral dose of 500?mg metformin sustained release products, test A (Glycomet SR), test B (Bigomet SR) and extended release reference product was administered as per computer generated randomization schedule during 3 period of the study having 7 days of washout period. A liquid Chromatography mass spectroscopy method for the determination of metformin in human plasma was developed and validated using metformin-D6 as an internal standard. A noncompartment pharmacokinetic method was employed to determine the pharmacokinetic parameters (Cmax, Tmax, AUC0-t, AUC0-∞ and t?) of metformin using WinNonlin-Node 4.0 software. Cmax, AUC0-t and AUC0-∞ were used to test for bioequivalence after log transformation of plasma data. The predetermined regulatory range of 90% CI for bioequivalence was 0.80 to 1.25. The 90% confidence intervals for log transformed data for Cmax, AUC0-t and AUC0-∞ for test A vs. reference were 82.11-98.91, 86.29-102.17 and 86.34-102.59 respectively whereas for test B vs. reference were 104.39-125.76, 94.78-112.22 and 92.85-110.33 respectively. The results of this study suggest that the test A was bioequivalent to reference product, whereas test B was not as per regulatory defined criteria.