• 한국임상약학회지
• /
• 제16권1호
• /
• pp.52-56
• /
• 2006

Aceclofenac, a nonsteroidal antiinflammatory agent of a phenylacetic acid type, has been used for rheumatoid arthritis and osteoarthrits. Although the metabolic pathway of aceclofenc is relatively well-known in vitro, pharmacokinetic profiles of its three major or metabolites are still unclear in human. The present study was designed to investigate pharmacokinetic profiles of the metabolites of aceclofenac, and to evaluate the bioequivalence of the generic preparation of aceclofenac 100 mg tablet. Blood samples were serially collected for a period of 12 hours following a single oral administration of 100 mg aceclofenac in 20 healthy human volunteers. A simple protein precipitation with acetonitrile was employed to purify those substances from plasma. Aceclofenac, diclofenac, 4'-hydroxyaceclofenac and 4'-hydroxy-diclofenac in heparinized plasma were simultaneously measured with flufenamic acid, an internal standard, using HPLC coupled to a tandem mass spectrometer. Time courses of 4'-hydroxydiclofenac, diclofenac and aceclofenac plasma concentrations were clearly revealed, and the pharmacokinetic properties were analyzed. The 90% confidence intervals for the ratios of test/reference for log-transformed AUC and $C_{max}$ lie within 0.80-1.25.

• The Korean Journal of Physiology and Pharmacology
• /
• 제13권5호
• /
• pp.367-371
• /
• 2009

The estimation of 90% parametric confidence intervals (CIs) of mean AUC and Cmax ratios in bioequivalence (BE) tests are based upon the assumption that formulation effects in log-transformed data are normally distributed. To compare the parametric CIs with those obtained from nonparametric methods we performed repeated estimation of bootstrap-resampled datasets. The AUC and Cmax values from 3 archived datasets were used. BE tests on 1,000 resampled data sets from each archived dataset were performed using SAS (Enterprise Guide Ver.3). Bootstrap nonparametric 90% CIs of formulation effects were then compared with the parametric 90% CIs of the original datasets. The 90% CIs of formulation effects estimated from the 3 archived datasets were slightly different from nonparametric 90% CIs obtained from BE tests on resampled datasets. Histograms and density curves of formulation effects obtained from resampled datasets were similar to those of normal distribution. However, in 2 of 3 resampled log (AUC) datasets, the estimates of formulation effects did not follow the Gaussian distribution. Bias-corrected and accelerated (BCa) CIs, one of the nonparametric CIs of formulation effects, shifted outside the parametric 90% CIs of the archived datasets in these 2 non-normally distributed resampled log (AUC) datasets. Currently, the 80~125% rule based upon the parametric 90% CIs is widely accepted under the assumption of normally distributed formulation effects in log-transformed data. However, nonparametric CIs may be a better choice when data do not follow this assumption.

• Journal of Pharmaceutical Investigation
• /
• 제33권3호
• /
• pp.229-235
• /
• 2003

The purpose of the present study was to evaluate the bioequivalence of two enalapril maleate tablets, $Renitec^{TM}$ (MSD Korea Ltd.) and $Enalace^{TM}$ (Welfide Korea Ltd.), according to the guidelines of Korea Food and Drug Administration (KFDA). Twenty-four normal male volunteers, $22.33{\pm}2.55$ year in age and $66.54{\pm}8.30$ kg in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After two tablets containing 10 mg of enalapril maleate per tablet were orally administered, blood was taken at predetermined time intervals and concentrations of enalapril in plasma were determined using LC-MS-MS. Pharmacokinetic parameters such as $AUC_t,\;C_{max}\;and\;T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_t,\;and\;C_{max}$ untransformed $T_{max}$. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals for the log transformed data were acceptance range of log0.8 to log1.25$(e.g.,\;log1.02{\sim}log1.14\;and\;log1.03{\sim}log1.19\;for\;AUC_t\;and\;C_{max},\;respectively)$. The major parameters, $AUC_t,\;and\;C_{max}$, met the criteria of KDFA for bioequivalence indicating that $Enalace^{TM}$ tablet is bioequivalent to $Renitec^{TM}$ tablet.

• Journal of Pharmaceutical Investigation
• /
• 제35권1호
• /
• pp.45-50
• /
• 2005

The purpose of the present study was designed to evaluate the bioequivalence of two ofloxacin tablets, Tarivid (Jeil Pharm. Co., Ltd.) and Favid (ILHWA Co., Ltd.), according to the guidelines of Korea Food and Drug Administration (KFDA). Twenty-four normal male volunteers, $23.67{\pm}3.12$ year in age and $68.50{\pm}7.23$ kg in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After four tablets containing 100 mg of ofloxacin were orally administered, blood was taken at predetermined time intervals and concentrations of ofloxacin in plasma were determined using HPLC. Pharmacokinetic parameters such as $AUC_t$, $C_{max}$ and $T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_t$ and $C_{max}$ and untransformed $T_{max}$. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals for the log transformed data were acceptance range of log 0.8 to log 1.25 (e.g., $log0.94{\sim}log1.04\;and\;log0.90{\sim}log1.07\;for\;AUC_t\;and\;C_{max}$, respectively). The major parameters, $AUC_t$, and $C_{max}$, met the criteria of KDFA for bioequivalence indicating that Favid tablet is bioequivalent to Tarivid tablet.

• Journal of Pharmaceutical Investigation
• /
• 제35권3호
• /
• pp.187-192
• /
• 2005

The purpose of the present study was designed to evaluate the bioequivalence of two benidipine hydrochloride tablets, Codipine (Youngjin Pharm. Co., Ltd.) and Benipine (Myungmoon Pharm. Co., Ltd.), according to the guidelines of Korea Food and Drug Administration (KFDA). Twenty-four normal male volunteers, $23.00{\pm}1.82$ year in age and $70.08{\pm}9.59$ kg in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After two tablets containing 4 mg of benidipine hydrochloride were orally administered, blood was taken at predetermined time intervals and concentrations of benidipine in plasma were determined using LC-MS/MS. Pharmacokinetic parameters such as $AUC_t$, $C_{max}$ and $T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_t$, and $C_{max}$. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals for the log transformed data were acceptance range of log0.8 to log1.25 $(e.g., \;log1.04{\sim}log1.24\;and\;log0.91{\sim}log1.09$ for $AUC_t$, and $C_{max}$ respectively). The major parameters, $AUC_t$ and $C_{max}$, met the criteria of KDFA for bioequivalence indicating that Benipine tablet is bioequivalent to Codipine tablet.

• Journal of Pharmaceutical Investigation
• /
• 제35권5호
• /
• pp.355-360
• /
• 2005

The purpose of the present study was to evaluate the bioequivalence of two cetirizine HCl tablets, Zyrtec tablet (UCB Pharm. Co., Ltd. Korea, reference product) and Zyrix tablet (Kukje Pharm. Co., Ltd., Korea, test product), according to the guidelines of Korea Food and Drug Administration (KFDA). After adding an internal standard (diazepam), plasma samples were extracted using 1 mL of dichloromethane. Compounds extracted were analyzed by reverse-phase HPLC with ultra-violet detector. This method for determination cetirizine is proved accurate and reproducible with a limit of quantitation of 10 ng/mL in male plasma. Twenty-four healthy male Korean volunteers received each medicine at the cetirizine HCl dose of 10 mg in a $2{\times}2$ crossover study. There was a one-week wash out period between the doses. Plasma concentrations of cetirizine were monitored for over a period of 24 hr after the administration. AUC (the area under the plasma concentration-time curve) was calculated by the linear trapezoidal rule. $C_{max}$ (maximum plasma drug concentration) and $T_{max}$ (time to reach $C_{max}$) were compiled from the plasma concentration-time data. Analysis of variance was carried out using logarithmically transformed AUC and $C_{max}$. No significant sequence effect was found for all of the bioavailability parameters indicating that the crossover design was properly performed. The 90% confidence intervals for the log transformed data were acceptable range of log 0.8 to log 1.25 $(e.g.,\;log\;0.93-log\;1.08\;for\;AUC_{0-t},\;log\;0.91-log\;1.08\;for\;AUC_{0-{\infty}}\;and\;log\;1.01-log\;1.11\;for\;C_{max})$. The major parameters, AUC and $C_{max}$ met the criteria of KFDA for bioequivalence indicating that Zyrix tablet is bioequivalent to Zyrtec tablet.

• Journal of Pharmaceutical Investigation
• /
• 제29권2호
• /
• pp.151-156
• /
• 1999

Bioequivalence of two fluoxetine capsules, the $Prozac^{\circledR}$ (Daewoong Lilly Pharmaceutical Co., Ltd.) and the $Lucetin^{\circledR}$ (Kyungdong Pharmaceutical Co., Ltd.), was evaluated according to the guideline of KFDA. Twenty normal male volunteers $(21{\sim}30\;years\;old)$ were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After three capsules containing 20 mg of fluoxetine per capsule were orally administered, blood was taken at predetermined time intervals, and the concentrations of fluoxetine in serum were determined using HPLC method with UV detector. The pharmacokinetic parameters ($AUC_t$, $C_{max}$ and $T_{max}$) were calculated and ANOVA test was utilized for the statistical analysis of parameters. The results showed that the differences in $AUC_t$, $C_{max}$ and $T_{max}$ between two capsules based on $Lucetin^{\circledR}$ capsules were -8.01 %, -7.02% and 1.49%, respectively. The powers $(1-{\beta})$ for $AUC_t$, $C_{max}$ and $T_{max}$ were 84.72%, 96.68% and 83.06%, respectively. Detectable differences $({\Delta})$ and confidence intervals were all less than ${\pm}20%$. All the parameters above met the criteria of KFDA for bioequivalence, indicating that $Lucetin^{\circledR}$ capsule is bioequivalent to $Prozac^{\circledR}$ capsule.

• 한국임상약학회지
• /
• 제15권2호
• /
• pp.82-88
• /
• 2005

A new medical system was started in Korea in 2000 and pharmaceutical affairs law was revised in 2001. According to the revised law, generic substitution is permitted only to therapeutically equivalent generic product. Bioequivalence studies are usually used to demonstrate therapeutic equivalence between reference listed drugs and generic drugs. The issues that are recently heating up in Korea are to increase bioequivalent drug products and at the same time to ensure the credibility of the therapeutic equivalence of generic drugs. Sometimes food can change the bioavailability (BA) of a drug and influence the bioequivalence (BE) between test and reference products as well. Food effects on BA can have clinically significant consequences. Food can alter BA by various means including delaying gastric emptying, stimulating bile flow and changing gastointestinal pH. This paper provides the recently published Korean guideline on food-effect BA and fed BE studies.

• Biomolecules & Therapeutics
• /
• 제9권4호
• /
• pp.285-290
• /
• 2001

Bioequivalence of two acetyl-1-carnitine tablets, test product (Carnitile tablet: Hanmi Pharm. Co., Ltd.) and reference product (Nicetil $e^{R}$ tablet: Dong-A Pharm. Co., Ltd.), was evaluated according to the guide- lines of Korea Food and Drug Administration (KFDA). Twenty-six healthy volunteers were divided randomly into two groups and administered the drug orally at the dose of 500 mg as acetyl-1-carnitine in a 2$\times$2 crossover study. Blood samples were taken at predetermined time intervals for 12 hours and the plasma concentration of acetyl-1-carnitine was determined using HPLC by derivatization with p-bromophenacyl bromide. The pearmacokinetic parameters (AU $C_{0-}$12h/ $C_{max}$ and $T_{max}$) were calculated and ANOVA was utilized for the statistical analysis of parameters. The apparent differences of these parameters between two drugs were less than 20% (i.e., 1.26,-5.08 and 8.59% for AU $C_{0-}$12h/ $C_{max}$ and $T_{max}$, respectively). The powers (1-$\beta$) for AU $C_{0-}$12h/ $C_{max}$ and $T_{max}$, and Tmax were over 0.9. Minimal detectable difference ($\Delta$) at $\alpha$=0.05, 1-$\beta$=0.8 were less than 20% (i.e.,7.31, 14.88 and 11.77% for AU $C_{0-}$12h/ $C_{max}$ and $T_{max}$, respectively). The confidence intervals ($\delta$) for these parameters were also within $\pm$ 20% (i.e.,-3.03$\leq$$\delta$$\leq$5.54, -13.80$\leq$$\delta$$\leq$3.64 and 1.69$\leq$$\delta$$\leq$15.48 for AU $C_{0-}$12h/ $C_{max}$ and $T_{max}$, respectively). These results satisfied the criteria of KFDA guideline for bioequivalence, indicating Carnitile bioequivalent to Nicetil $e^{R}$ .TEX>$^{R}$ .> R/ . R/ .

• Journal of Pharmaceutical Investigation
• /
• 제39권4호
• /
• pp.233-242
• /
• 2009

Bioequivalence (BE) studies provide important information in the overall set of data that ensure the availability of safe and effective medicines to patients and practitioners. Thus its determination of proper criterion for assessing BE is very important. BE is frequently expressed or measured by estimating area under the plasma concentration-time curve (AUC) and maximum concentration ($C_{max}$) that are reflective of systemic exposure. In all countries except Canada, the acceptance criteria of BE is that the 90% confidence interval of difference in the average values of logarithmic AUC and $C_{max}$ between test and reference products is within the acceptable range of log(0.8) ${\sim}$ log(1.25). In Canada, unlike other countries, point estimation instead of applying 90% confidence interval is applied to assess $C_{max}$ which is, in essence, more variable than AUC. We also compared other parts of BE guidelines which include a fed study, average BE (ABE), scaled-ABE, population BE (PBE), individual BE (IBE), dropout & withdrawal, sampling frequency & time and number of subjects. This article reviews the most recent BE guidelines of Korea, USA, Europe, Canada and Japan, highlighting the differences focused on Korean BE guidelines compared to other countries. It will help us to revise BE guideline of Korea reflecting international trends. Finally, it is strongly recommended that the extended acceptance criterion for the highly variable drug among all the considering aspects for the revision of current BE guideline has to be adopted into Korea BE guideline in the nearest future.