Comparative bioavailability study of two cefixime formulations administered orally in healthy male volunteers

The bioavailability of a new cefixime ((6R,7R)-7-[(Z)-2-(2-amino-4-thiazolyl)-2-(carboxymethoxyimino) acetamido]-8-oxo-3-vinyl-5-thia-1-azabicyclo-[4,2,0]-oct-2-ene-2-carboxylic acid, CAS 79350-37-1) tablet preparation (Loprax) was compared with that of a reference preparation of the drug in 24 healthy male volunteers. The trial was designed as an open, randomized, single-blind, two-sequence, two-period crossover study. Under fasting conditions, each subject received a single oral dose of 400 mg cefixime tablet as a test or reference formulation on 2 treatment days. The treatment periods were separated by a one-week washout period. The plasma concentrations of the drug were analyzed by a rapid and sensitive HPLC method with UV detection. The pharmacokinetic parameters included AUC0-24h, AUC0-infinity, Cmax, t1/2, and Ke. The mean AUC0-infinity of cefixime was 45008.7 +/- 10989.9 and 45221.3 +/- 2155.7 n x h/ml for the test and reference formulation, respectively. The maximum plasma concentration (Cmax) of cefixime was on average 4746.9 +/- 1284 ng/ml for the test and 4726.3 +/- 1206.9 ng/ml for the reference product. No statistical differences were observed for Cmax and the area under the plasma concentration-time curve for test and reference tablets. The calculated 90% confidence intervals based on the ANOVA analysis for the mean test/reference ratios of Cmax, AUC0-infinity and AUC0-24h of cefixime were in the bioequivalence range (94%-112%). Therefore, the two formulations were considered to be bioequivalent.     

Pharmacokinetics/bioavailability of colchicine in healthy male volunteers

In a randomized 2-way cross-over study with twelve healthy male volunteers, two colchicine preparations (tablets, A vs. oral solution, B) were tested. The preparations were administered as single doses of 1 mg; prior to and up to 72 h after medication blood samples were collected and the plasma colchicine concentrations determined. Additionally urine samples were collected at 0-2, 2-4, 4-6, 6-8, 8-10, 10-24, 24-48, 48-72 and 72-96 h intervals. The colchicine plasma and urine concentrations were determined by a newly developed and validated RIA method. The mean area under the plasma concentration-time curve (AUC-1, AUC-3) was calculated as 23.95 +/- 12.10 (AUC-1) and 26.73 +/- 12.75 (AUC-3) h.ng/ml after application of A and 28.01 +/- 14.74 (AUC-1) and 31.57 +/- 16.58 (AUC-3) h.ng/ml after application of B, respectively. Mean peak plasma concentrations of 4.15 +/- 2.35 (A) and 4.88 +/- 3.90 (B) ng/ml were reached at 1.15 +/- 0.38 (A) and 1.13 +/- 0.42 (B) h after application. The mean terminal half-lives accounted for 9.31 +/- 3.98 (A) and 10.57 +/- 5.53 (B) h. The mean total clearance (Cl/F) and volume of distribution (V/F) were found to be 40.12 +/- 20.87 (A) and 46.58 +/- 24.65 (B) l/h and 472.59 +/- 196.46 (A) and 624.89 +/- 304.09 (B) l, respectively. The mean total amount excreted in urine (Ae) was 172.66 +/- 91.51 (A) and 174.85 +/- 63.53 (B) micrograms.(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparative bioavailability of metoprolol tartrate after oral and transdermal administration in healthy male volunteers

BACKGROUND AND OBJECTIVE: Transdermal drug delivery systems (TDDSs) of metoprolol tartrate have been previously prepared and evaluated in vitro and in vivo in an animal model. This study compares the bioavailability of metoprolol tartrate from a TDDS with that from a conventional marketed tablet in healthy human volunteers. METHODS: This was an open-label, balanced randomised, two-treatment, two-period crossover study with a washout period of 1 week. Volunteers were randomised (by means of a SAS software-generated randomisation schedule) to have a TDDS applied to their chest for 48 hours or to receive a 100 mg conventional marketed tablet of metoprolol tartrate in period I. In period II, the volunteers received the other dosage form. Blood samples were collected through an indwelling cannula placed in the forearm vein of each subject. Metoprolol tartrate concentrations were quantified in plasma samples by a validated high-performance liquid chromatography method. RESULTS: A 3-fold improvement in bioavailability was observed with the TDDS form over oral therapy as shown by the extent of absorption indicated by the mean area under the concentration-time curve from time zero to time t values for tablets (451.98 ng x h/mL) and TDDS (1552.66 ng x h/mL). Although the maximum plasma concentration was higher for the tablet form than the TDDS (77.67 +/- 23.33 vs 51.16 +/- 16.61 ng/mL), the variable absorption profile, which is a characteristic feature of oral therapy, was quite evident. Plasma metoprolol tartrate concentrations plummeted to therapeutically ineffective concentrations as early as 8 hours following oral administration. CONCLUSION: The TDDS developed in our laboratory produced therapeutically effective plasma concentrations for up to 48 hours, with a minimum of 26.09 ng/mL and a maximum of 76.70 ng/mL, which is in good agreement with the therapeutic range (20-100 ng/mL) of metoprolol tartrate. It could be concluded that the TDDS meets the intended goal of 2-day management of hypertension with application of a single patch, obviating the inconvenience of frequent administration and thus improving patient compliance.     

Comparative bioavailability of clarithromycin formulations in healthy brazilian volunteers

OBJECTIVE: To compare the bioavailability of clarithromycin 500 mg tablets (Merck S.A Industrias Quimicas, Sao Paulo, SP, Brazil, used as test formulation) and Klaricid (Abbott Laboratórios do Brasil Ltda, Sao Paulo, SP, Brazil, used as reference formulation) in 24 healthy volunteers. MATERIAL AND METHODS: The study was conducted using an open, randomized, two-period crossover design with one-week interval between doses. Blood samples were collected at pre-dose, 0.33, 0.66, 1, 1.33, 1.66, 2, 2.5, 3, 4, 6, 8, 10, 12, 16, 20 and 24 hours after the administration. AUC was calculated by the trapezoidal rule extrapolation method. Cmax and tmax were compiled from the plasmatic concentration-time data. Analysis of variance was carried out using logarithmically transformed AUC(0-inf), AUC(0-24 h), Cmax and untransformed tmax. RESULTS: Intraindividual coefficient of variation (CV%) values were 14.25% and 12.62%, respectively for Cmax and AUC(0-24 h). The geometric mean values (+/- SD) for AUC(0-24 h) (microg x h/ml), AUC(0-inf) (microg x h/ml), and Cmax (microg/ml) for test medication were 18.56 (+/- 6.87), 18.8 (+/- 5.70) and 2.45 (+/- 0.88); the obtained values for reference medication were 18.29 (+/- 5.39), 19.10 (+/- 7.21) and 2.5 (+/- 0.69). 90% Cl for clarithromycin geometric mean of AUC(0-24 h), AUC(0-inf) and Cmax ratios (test/reference) were: 93.6-105.9%, 93.8-106.2% and 89- 103.2%. CCONCLUSION The test medication was considered bioequivalent to the reference medication based on the rate and extent of absorption.     

Comparative bioavailability cf two amlodipine formulation in healthy volunteers

The present study was conducted to find out whether the bioavailability of a 10 mg amlodipine (CAS 88150-42-9) tablet (Intervask, "test") was equivalent to that that of a reference formulation ("reference"). The pharmacokinetic parameters assessed in this study were area under the serum concentration-time curve from time zero to 144 h (AUCt), area under the serum concentration-time curve from time zero to infinity (AUCinf), the peak serum concentration of the drug (Cmax), time needed to achieve the peak serum concentration (tmax), and elimination half life (t(1/2)). This was a cross-over, randomized, single-blind study which included 12 healthy male and female volunteers under fasting condition. In each of the two study periods (separated by a washout of 3 weeks) a single dose of test or reference drug was administered. Blood samples were taken up to 144 h post dose, the plasma was separated and the concentrations of amlodipine were determined by a LC/MS method. The mean AUCt, AUCinf, Cmax, and t(1/2) were 353.15 ng x h/mL, 417.86 ng x h/mL, 8.08 ng/mL, and 48.04 h, respectively, for the test drug and 359.99 ng x h x mL(-1), 408.23 ng x h/mL, 8.22 ng/mL, and 43.81 h, respectively, for the reference drug. The median Tmax of the test drug and reference drug were 8.0 h and 8.5 h, respectively. The point estimators of the ratios test/reference drug for AUCt, AUCinf, and Cmax were 96.26%, 99.48%, and 97.03%, respectively. Furthermore, the 90% confidence intervals of the mean ratio of In-transformed were 83.73-110.68% for AUCt, 81.79-120.99% for AUCinf, and 81.94-114.81% for Cmax. It can be concluded that the two amlodipine tablets (test drug and reference drug) are bioequivalent in terms of the rate and extent of absorption.     

Comparative bioavailability of two fluconazole capsule formulations in healthy volunteers

This work reports the bioavailability of two fluconazole (CAS 86386-73-4) capsule formulations in 24 healthy volunteers of both sexes who received a single oral dose (150 mg). The study was conducted using an open, randomized, two-period crossover design with two-week washout interval. Plasma samples were obtained up to 168 h after drug administration and fluconazole concentration were analyzed using electrospray tandem mass spectrometry coupled to liquid chromatography. The pharmacokinetic parameters obtained for fluconazole after the administration of each formulation included the area under the curve (AUC)(0-168 h), AUC(0-infinity), maximum concentration (Cmax), time to reach Cmax (Tmax), elimination constant (Ke) and half-life (T1/2). The 90% confidence interval for the geometric mean of the individual ratio test formulation/reference formulation were 97.18-108.60% for AUC0-168 h), 90.87-111.11% for AUC(0-infinity), 104.88-114.88% for Cmax 90.38-136.79% for Ke, 91.87-108.93% for T1/2 and (-)1.5-(-)0.10 for Tmax (for individual differences). Since for both Cmax or AUC the 90% CI are within the interval proposed by the Food and Drug Administration (FDA), the test formulation (Zoltrix) is bioequivalent to the reference formulation for both the rate and the extent of absorption after single dose administration.     

Comparative bioavailability of two different diclofenac formulations in healthy volunteers

The aim of the study was to assess the bioequivalence of two different diclofenac (CAS 15307-86-5) formulations (diclofenac free acid suspension as test formulation and diclofenac resinate suspension, Cataflam, as reference formulation) in 24 healthy volunteers. After an overnight fast, the volunteers received a single oral dose (50 mg) of each formulation, following an open, randomized, two-period crossover design, with a fourteen-day washout interval between doses. Serum samples were obtained over a 24-h interval post-dosing, and were analysed for their diclofenac content by HPLC-UV. No adverse effect was reported for any of the formulations administered. Geometric mean test/reference individual ratios were: 92.8% for AUC(0-24 h), 93.2% for AUC(0-infinity), 117.2% for Cmax, 131.0% for Ke and 76.2% for T1/2. The variability of Cmax parameter expressed as CV was greater than 25%. Since the 90% CI for AUC(0-24 h) mean ratio were within the 80-125% interval proposed by the Food and Drug Administration, it can be concluded that diclofenac free acid formulation is bioequivalent to diclofenac resinate formulation for the extent of absorption. Since the European Community Agency accepts a 90% CI for Cmax of 70-143%, it can be concluded that diclofenac free acid formulation is bioequivalent to diclofenac resinate formulation for both the rate and the extent of absorption after single dose administration.     

Comparative bioavailability of three ibuprofen formulations in healthy human volunteers

OBJECTIVE: To assess the bioequivalence of three ibuprofen formulations (Test formulation: ibuprofen (400 mg capsule) manufactured by Cardinal Health Brasil 402 Ltda. (Sorocaba, Brazil) and licensed to Boehringer Ingelheim do Brasil Quim. e Farm. Ltda. (SA poundo Paulo, Brazil); Reference formulation (1): ibuprofen (AdvilA(R); 2 A 200 mg coated tablet) from Wyeth-Whitehall Ltda. (Itapevi, Brazil); Reference formulation (2): ibuprofen (AliviumA; 8 ml A 50 mg/ml solution) from Schering Plough S.A. (Rio de Janeiro, Brazil)) in 24 healthy volunteers of both sexes. METHODS: The study was conducted using an open, randomized, three-period crossover design with at least 5-day washout interval. Plasma samples were obtained over a 24-h period. Plasma ibuprofen concentrations were analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) with negative ion electrospray ionization using multiple reaction monitoring (MRM). The following pharmacokinetic parameters were obtained from the ibuprofen plasma concentration vs. time curves: AUC(last), AUC(trunctmax), AUC(inf) and C(max). RESULTS: The limit of quantification for ibuprofen was 0.1 microg A ml(1). The geometric mean with corresponding 90% confidence interval (CI) for Test/Reference (1) percent ratios were 114.24% (90% CI = 105.67, 123.50%) for C(max), 98.97% (90% CI = 94.69, 103.44%) for AUC(last) and 99.40% (90% CI = 95.21, 103.78%) for AUC(inf). The geometric mean and respective 90% confidence interval (CI) for Test/Reference (2) percent ratios were 108.38% (90% CI = 100.19, 117.25%) for C(max), 100.79% (90% CI = 96.39, 105.40%) for AUC(last) and 101.26% (90% CI = 96.94, 105.77%) for AUC(inf); t(max) for the 400 mg Test capsule was shorter than that for the 2 A 200 mg Reference (1) tablets (p < 0.002). Conclusion: Since the 90% CI for AUC(last), AUC(inf) and Cmax ratios were within the 80 - 125% interval proposed by the US FDA, it was concluded that ibuprofen formulation manufactured by Cardinal Health Brasil 402 Ltda. and licensed to Boehringer Ingelheim do Brasil Quim. e Farm. Ltda. is bioequivalent to the AdvilA and AliviumA formulations with regard to both the rate and the extent of absorption.     

替米沙坦在中国健康人体内的药代动力学和相对生物利用度研究

目的:研究替米沙坦在中国人体内的药代动力学和相对生物利用度。方法:2 0名男性健康志愿者单剂量随机交叉口服80mg国产替米沙坦胶囊(试验片)和进口替米沙坦片(参比片) ,采用HPLC 荧光检测法测定受试者96h的血药浓度,生物等效性采用双侧t检验。结果:国产和进口的替米沙坦血药浓度 时间曲线符合二室开放模型,其主要药代动力学参数:Cmax分别为4 5 6 .2 8±2 5 2 .5 6和75 9.5 4±313.5 4μg·L- 1,Tmax分别为1.6 1±0 .71和1.0 8±0 .36h ,T1/ 2 β分别为2 2 .39±6 .2 9和2 1.0 8±5 .2 4 ,MRT分别为2 7.0 2±6 .2 3和2 4 .2 7±5 .79h ,AUC0 -t分别为345 4±10 5 0和36 36±130 0 μg·h·L- 1,统计分析,试验片与参比片的Cmax、Tmax有统计学差异(P <0 .0 5 ) ,而AUC0 -t没有显著性差异(P >0 .0 5 ) ,试验片相对生物利用度为97.2 8%±12 .74 %。结论:国产替米沙坦胶囊和进口片剂具有生物等效性。     

阿替洛尔片在人体内的相对生物利用度与生物等效性

目的考察阿替洛尔片(AT)在人体内相对生物利用度及生物等效性。方法22名男性健康受试者,采用单剂量、随机、自身交叉对照试验设计,空腹poAT试验片和参比制剂各50 mg后,用RP-HPLC荧光检测法检测血浆中AT经时血药浓度,计算药动学参数和相对生物利用度。结果AT的相对生物利用度为100.6%±33.0%。主要药动学参数的方差分析和双单测t检验表明,试验制剂和参比制剂的AUC0~t、Cmax无显著性差异(P>0.05),AT试验制剂的AUC0~t、Cmax的90%的置信区间分别为90.72%~111.86%、87.48%~117.29%。结论AT试验片和参比制剂具有生物等效性。     

Comparative oral bioavailability of non-fixed and fixed combinations of artesunate and amodiaquine in healthy Indian male volunteers

Objective  

The aim of the present study was to compare the pharmacokinetic properties, bioavailability and tolerability of artesunate (AS) and amodiaquine (AQ) administered as a fixed-dose combination (Amonate FDC tablets; Dafra Pharma, Turnhout, Belgium) or as a non-fixed dose combination of separate AS tablets (Arsuamoon; Guilin Pharmaceutical Co, Shanghai, China) and AQ tablets (Flavoquine; Sanofi-Aventis, Paris, France).     

Comparative bioavailability of 875 mg amoxicillin tablets in healthy human volunteers

OBJECTIVE: To compare the bioavailability of amoxicillin 875 mg tablets (EMS Sigma Pharma used as test formulation) and Amoxil BD 875 mg tablets (GlaxoSmithKline used as reference formulation) in 26 healthy volunteers. MATERIAL AND METHODS: 26 healthy volunteers (13 males and 13 females) received each formulation in an open, 2 x 2 crossover, randomized study with seven days of washout period between doses. Plasma samples were obtained over a 12-hour interval after administration. Plasmatic amoxicillin concentrations were obtained by combined reversed-phase liquid chromatography and mass spectrometry with positive ion electrospray ionization using the select ion monitoring method. AUC was calculated by the trapezoidal rule extrapolation method. Cmax and tmax were compiled from the plasmatic concentration-time data. Analysis of variance was carried out using logarithmically transformed AUC0-inf, AUC0-12 h, Cmax and untransformed tmax. RESULTS: The mean values (+/- SD) for AUC0-12 h (microg x h x ml(-1)), AUC0-inf (microg x h x ml(-1)), Cmax (microg x ml(-1)), t1/2 (h) and tmax (h), were, respectively: 55.42 (+/- 16.85), 55.42 (+/- 16.85), 18.59 (+/- 6.3), 1.49 (+/- 1.57) and 2.04 (+/- 0.75) concerning the test formulation, and 51.11 (+/- 18.9), 51.29 (+/- 19.12), 17.83 (+/- 5.86), 1.52 (+/- 1.31) and 2.02 (+/- 0.87) concerning the reference formulation. Confidence intervals (90%) of amoxicillin means of AUC0-12 h and Cmax ratios (test/reference) were: 0.961-1.149 and 0.914-1.142, respectively, agreeing with the bioequivalence criteria established by the Brazilian National Health Surveillance Agency. CONCLUSION: Both formulations were bioequivalent based on both the rate and extent of absorption.     

Comparative bioavailability of two cetirizine tablet formulations in Indonesian healthy volunteers

AIM: To compare the bioavailability of two cetirizine tablet (10 mg) formulations (ZyrtecA from UCB Pharma, Spain as a reference formulation and RyvelA from Novell Pharmaceutical Laboratories, Indonesia as a test formulation). MATERIAL AND METHODS: The study was conducted according to an open, randomized, two-period crossover design with a 1-week washout period. Eighteen volunteers participated and all completed the study successfully. Blood samples were obtained prior to dosing and at 0.25, 0.5, 1, 2, 3, 5, 8, 12, 24 and 30 hours after drug administration. Plasma concentrations of cetirizine were monitored using high-performance liquid chromatography over a period of 30 hours after administration. The pharmacokinetics parameter AUC(0-30h), AUC(0-infinity) and C(max) were tested for bioequivalence after log-transformation of data and ratios of t(max) were evaluated non-parametrically. RESULT: The point estimates and 90% confidence intervals for AUC(0-30h), AUC(0-infinity) and C(max) were 108.23% (101.90 a 114.95%), 108.11% (101.91 a 114.68%) and 99.71% (90.18 a 110.25%), respectively, satisfying the bioequivalence criteria of the European Committee for Proprietary Medicinal Products an the US Food and Drug Administration guidelines. CONCLUSION: These results indicate that two medications of cetirizine are bioequivalent and, thus, may be prescribed interchangeably.     

甲磺酸加替沙星胶囊与片剂的相对生物利用度研究

目的:评价甲磺酸加替沙星胶囊剂对片剂的相对生物利用度.方法:选择24例18～40岁健康成年男性受试者,随机分为2组,自身前后交叉依次口服甲磺酸加替沙星胶囊剂与片剂400mg,应用高效液相色谱法测定各受试者给药后不同时间点的血药浓度,采用3P97软件进行数据处理,计算药动学参数,应用STAT进行统计分析.结果:甲磺酸加替沙星胶囊剂与片剂药-时曲线符合二房室模型,胶囊剂与片剂达峰时间(Tmax)分别为(1.16±0.40)和(1.10±0.40)h;峰浓度(Cmax)分别为(3.91±0.61)和(3.85±0.83)mg·L-1;血浆生物半衰期(t1/2)分别为(6.77±1.65)和(7.28±1.20)h;血药浓度-时间曲线下面积(AUC0～t)分别为(28.23±4.77)和(26.88±6.54)mg·h·L-1.胶囊剂与片剂主要药动学参数无显著差异.结论:甲磺酸加替沙星胶囊剂相对于片剂的相对生物利用度为105.4%.     

Relative bioavailability study of two nifedipine tablet formulations in healthy male volunteers

OBJECTIVE: To assess the bioequivalence of two oral formulations containing 10 mg of nifedipine. The test preparation were Macorel tablets, the reference preparation were Adalat tablets. SUBJECTS, MATERIAL AND METHODS: The study was designed as a single-dose, three-period crossover randomized design to 18 non-smoker, healthy male volunteers under fasting conditions. Seventeen volunteers completed the study. Plasma samples were analyzed for nifedipine by HPLC after solid-phase extraction. The pharmacokinetic parameters used to assess the bioequivalence of the two formulations were AUC(0-infinite) and AUC(0-t) for the extent of absorption and Cmax and Tmax for the rate of absorption. Statistical comparisons of AUC(0-infinite) AUC(0-t), and Cmax data were evaluated after logarithmic transformation by two-way analysis of variance (ANOVA), and differences of Tmax were tested non-parametricaly. RESULTS: Point estimates (90% confidence intervals) of the test/reference ratios were 97.4% (87.6%-108.3%) for AUC(0-infinite) 97.0% (85.6%-110.1%) for AUC0-t, and 107.7% (89.1%-130.7%) for Cmax. No statistically significant difference was found for Tmax and elimination half-life values. CONCLUSION: Therefore, in accordance with the European Union bioequivalence requirements, the test and reference nifedipine preparations are bioequivalent for both the extent and the rate of absorption.     

二甲双胍片在中国健康男性志愿者中的药代动力学及其生物利用度

目的研究中国健康志愿者口服二甲双胍片的人体药代动力学和相对生物利用度.方法18名健康志愿受试者随机双交叉口服二甲双胍受试药和参比药各 1 000 mg,阳离子交换柱HPLC法测定血浆中二甲双胍浓度.结果受试药及参比药药代动力学参数分别为T1/2 2.9±0.2 与 3.0±0.5 h;Cmax 1.8±0.5 与 1.7±0.3 mg*L-1;Tmax 1.6±0.7 与 2.4±0.8 h ;AUC0～12 8.6±1.9 与 8.6±2.0 mg*h-1*L-1.受试药相对生物利用度为102±14%.结论试验药和参比药药动学参数相似,在吸收上具有生物等效性.     

Comparative bioavailability study with two chlorpropamide tablet formulations in healthy volunteers

OBJECTIVE: The aim of this study was the assessment of the bioequivalence of two formulations (250 mg tablet) of chlorpropamide (CAS 94-20-2) in 36 healthy volunteers of both sexes. METHODS: The study was conducted using an open, randomized, two-period crossover design with a 3-week washout interval. Plasma samples were obtained over a 72-h period. Plasma chlorpropamide concentrations were analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS-MS) with positive ion electrospray ionization using multiple reaction monitoring (MRM). From the chlorpropamide plasma concentration vs time curves, the following pharmacokinetic parameters were obtained: AUC(0-72h), AUC(inf) and C(max). RESULTS: The limit of quantification was 0.1 microg/mL for plasma chlorpropamide analysis. The geometric mean and respective 90 % confidence interval (CI) of Test/ Reference percent ratios were 93.99% (87.11%-101.41%) for C(max), 92.45% (85.96%-99.44%) for AUC(0-72h) and 90.30% (83.35%-97.82%) for AUC(0-inf). CONCLUSION: Since the 90 % CI for AUC(0-72h), AUC(0-inf) and C(max) ratios were within the 80-125%interval proposed by the US FDA, it was concluded that chlorpropamide 250 mg tablet (test formulation) was bioequivalent to the reference 250 mg tablet for of both the rate and extent of absorption.     

Comparative bioavailability study with two gemfibrozil tablet formulations in healthy volunteers

OBJECTIVE: To assess the bioequivalence of gemfibrozil (CAS 25812-30-0) 900 mg tablet formulation from EMS Farmaceutica as test formulation versus a 900 mg tablet formulation as reference in 36 healthy volunteers of both sexes. METHODS: The study was conducted using an open, randomized, two-period crossover design with a 1-week washout interval. Plasma samples were obtained over a 24-h period. Plasma gemfibrozil concentrations were analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS-MS) with negative ion electrospray ionization using multiple reaction monitoring (MRM). From the gemfibrozil plasma concentration vs time curves, the following pharmacokinetic parameters were obtained: AUClast, AUC(0-inf) and Cmax. RESULTS: The limit of quantification was 0.05 microg/mL for plasma gemfibrozil analysis. The geometric mean and respective 90% confidence interval (CI) of Test/Reference percent ratios were 90.29 (81.39-100.17) for Cmax, 96.26 (90.33-102.59) for AUClast, 96.04 (90.21-102.23) for AUC(0-24 h) and 96.62 (90.82-102.78) for AUC(0-infinity). CONCLUSION: Since the 90% CI for AUClast, AUC(0-inf) and Cmax, ratios were within the 80-125% interval proposed by the U.S. FDA, it was concluded that gemfibrozil 900 mg tablet (test formulation) was bioequivalent to the 900 mg tablet reference formulation for both rate and extent of absorption.     

Comparative fasting bioavailability and pharmacokinetic properties of 2 formulations of glucosamine hydrochloride in healthy Chinese adult male volunteers

Glucosamine (CAS 66-84-2) hydrochloride is an amino monosaccharide indicated for the treatment of arthrosis, especially osteoarthritis of the knee joint. This study was conducted to assess and compare the pharmacokinetic (PK) properties, bioavailability of a newly developed dispersible tablet formulation (test) of glucosamine hydrochloride with those of an established branded capsule formulation (reference) in healthy Chinese adult male volunteers.This single-dose, randomized, open-label, 2-period crossover study was conducted in 18 healthy Chinese adult male volunteers under fasting condition. Plasma samples were collected at pre-specified times over a 12-h period following administration in each period and analyzed the plasma glucosamine concentrations by Liquid Chromatography coupled with Tandem Mass Spectrometry (LC/MS/MS) method. The mean (SD) PK parameters of Cmax, Tmax, AUC0-12, and AUC0-∞ after administration of the test and reference formulations were, respectively, as follows: Cmax, 907.01 (444.22) vs. 944.40 (429.89) ng/mL, Tmax, 3.03 (0.95) vs. 3.30 (0.99) hours, AUC0-12, 2891.41 (1352.30) vs. 2889.69 (925.48) ng/mL/h, and AUC0-∞, 3029.90 (1321.36) vs. 3091.87 (870.36) ng/mL/h. The mean (SD) t1/2 was 1.10 (0.52) hours for the test formulation and 1.50 (1.17) hours for the reference formulation. On ANOVA, neither period nor sequence effects were observed for any PK properties. The relative bioavailability of the test formulation was 98.3% assessed by AUC0-12. The 90% CIs of glucosamine for the log-transformed ratios of Cmax, AUC0-12, and AUC0-∞ were 78.4-113.9%, 80.8-108.5% and 80.8-105.8%, respectively, meeting the predetermined criteria for bioequivalence of SFDA.