Earticle

Clopidogrel is used to reduce the risk of cardiovascular events in patients with atherosclerosis documented by recent ischemic stroke, recent myocardial infarction (MI), or established peripheral arterial disease (secondary prevention). Clopidogrel is metabolized by CYP3A4, and the active metabolites inhibit platelet aggregation. The purpose of this study was to assess clopidogrel only versus clopidogrel + others (aspirin, CYP3A4 inhibitor, and CYPBA4 inducer) in terms of cardiovasculalr events and bleeding complications. We reviewed the charts of patients who visited between August 1, 2002 and August 31, 2003, retrospectively. Total 72 patients were included and they consisted of 5 groups; clopidogrel group (n=36), clopidogrel + aspirin group (n=11), clopidogrel + CYP3A4 inhibitor group (n=15), clopidogrel + aspirin + CYP3A4 inhibitor group (n=6), clopidorel + CYP3A4 inducer group (n=4). The primary endpoints at 6 months, 12 months were the composite of cardiovascular (CV) events. The secondary end-point was the incidence of bleeding events at 6months, and 12months. At 12months, the primary endpoint was not significantly different among the five groups (p=0.056). In comparison of two groups as clopidogrel only versus clopidogrel + others (aspirin, CYP3A4 inhibitor and CYP3A4 inducer), the primary endpoint was significantly different (p=0.02). The CV events were increased in the clopidogrel + others group. The secondary end point was not significantly different among the five groups (p=0.52). However, time to bleeding events was 230.8 in the clopidogrel group and 74.7 in the clopidogrel + others group (p = 0.046). In conclusion, clopidogrel interaction with aspirin, CYP3A4 inhibitor, and CYP3A4 inducer affected cardiovascular events and bleeding events. Drug interaction of clopidogrel with concurrent medications should be considered cautiously.

Cholestatic liver disease is a frequent complication of prolonged parenteral nutrition, especially in premature infants. Numerous factors have been cited as contributing to TPN associated cholestasis. However the exact etiology remains obscure. Ursodeoxycholic acid (UDCA) has been reported to be beneficial far children and adults with various chronic cholestatic liver disease. The aim of this prospective, randomized, double-blind, placebo-controlled study was to determine the preventive effects of UDCA administration during TPN. Seventeen pediatric patients (8 boys and 9 girls) undergoing TPN were assigned randomly to two groups, UDCA and placebo group. UDCA group (n=9) received 15 mg/kg/day UDCA and placebo group (n=8) received 15 mg/kg/day placebo enterally during the TPN period. Liver function tests (total bilirubin, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase) were per-formed before TPN and weekly or three times a week. The patients' weights, complete blood count, composition of TPN, and the infusion rate of TPN and lipid were monitored everyday. Calcium and phosphate were monitored twice a week. Between the UDCA and placebo groups, there were no differences in weight at the onset of TPN, birth weight, duration of TPN, respiratory distress syndrome associated with prematurity, age at the onset of TPN, gestational age, the number of days the patients received antibiotics, the number of patients received enteral nutritions and the composition of TPN. In contrast, there was a significant difference between the UDCA and placebo groups in alanine aminotransferase levels during TPN. It doesn't seem that UDCA administration during TPN correlates directly with improvement of liver function. But the preventive administration of UDCA may be effective in reducing liver enzyme, alanine aminotransferase and has no adverse effects.

A bioequivalence study of CKD capsule (Chong Kun Dang Pharm Co., Ltd) to capsule (Lilly Korea Co., Ltd.) was conducted according to the guidelines of Korea Food and Drug Administration (KFDA). Twenty four healthy male Korean volunteers received each medicine at the cefaclor dose of 250 mg in a crossover study. There was a one-week washout period between the doses. An improved high-performance liquid chromatorgraphy (HPLC) analytical method with UV detection was used to determine plasma cefaclor concentration in human volunteers for 8 hr after oral drug administration. The area under the plasma concentration-time curve from time zero to 8 hr () was calculated by the linear trapezoidal rule. the (maximum plasma drug concentration) and (time to reach ) were compiled from the plasma concentration-time data. Analysis of variance was carried out using logarithmically transformed . No significant sequence effect was found for all of the bioavailability parameters indicating that the cross-over design was properly performed. The confidence intervals of the ratio and the ratio for CKD and were and , respectively. These values were within the acceptable bioequivalence intervals of 0.80-1.25. Thus, our study demonstrated the of CKD capsule was bioequivalent to capsule with respect to its bioavailability.

This study was intended to contribute towards the development of proper drug use system for pediatric patients by investigationg problems related to their medication and identifying drugs that need to be developed into low dosage tab-lets or syrups for pediatric use based on our analysis on the prescriptions for pediatric inpatients from 22 hospitals in South Korea on a day of Feb. 2003. The usage rates in the proportion of less than 0.5 and 1 per unit of oral solid formulation were and in hospitals with 1000 beds or more, 36.5 and in hospitals with 500 to less than 1000 beds, and in hospitals with less than 500 beds. Of the 63 oral solid formulation products that were used two or more times in the proportion oi less than 0.5 units, 34 products () were used as such despite the fact that syrups and lower dosage tablets or capsules were available in the market, and 24 products () so even when syrup formulations were available. Therefore, it would be desirable that pharmacist communities in charge of dispensing identify the most frequently crushed drugs or those that require special attention in choosing dispensing powders or solutions and develop dispensing guidelines that can be adopted by pharmacists in practice. Moreover government-led policies are needed to encourage development and manufacture of the formulations for pediatrics and to correct unsound prescription and dispensing practices such as using crushed forms of certain oral solid formulations although alternative formulations are available in the market.

We examined the effects of food on pharmacokinetic and pharmacodynamic properties of fenofibrate released from sustained-release(SR) capsule as therapy for hypolipidemia. Twenty-four healthy volunteers were used in crossover pharmacokinetic and pharmacodynamic study; Additional six volunteers were used as a control group (i.e., no fenofibrate administration). A single dose of fenofibrate (SR capsule, 250 mg) was administered on three occasions: after overnight fasting, after consumption of a standard breakfast, and after a high-fat breakfast. Serial blood samples were collected for the next 72 hours. Plasma fenofibric acid concentrations were measured by high performance liquid chromatography, and pharmacokinetic parameters were calculated using ADAPT II program. Plsama triglyceride concentrations were measured by blood chemistry analyzer (CH-100). The pharmacokinetic parameters were significantly affected by food intake. The high-fat breakfast affected the rate of absorption of fenofibrate more than did the standard breakfast and fasted conditions. Plasma concentrations of triglyceride at 24 hours decreased significantly after the administration of fenofibrate compared with the concentration at 0 hours(P<0.05). In healthy volunteers, the bioavailability of fenofibrate was greater when administered via sustained-release capsules immediately after the consumption of food than after fasting condition.

심바스타틴은 cholesterol 생합성 과정에서 속도 조절 효소인 HMG-CoA reductase의 강력한 상경적 길항약으로서 고지혈증 치료에 널리 쓰이는 약물이다. 심바스타틴 제제인 MSD 사의 조코 20 mg정을 대조약으로 하여 시험약인 유영 제약의 엘바스타 20mg정의 생물학적 동등성 평가를 하기 위해 22명의 건강한 지원자를 모집하였다. 지원자를 두 군으로 나누어 2정씩 투여하였고 교차시험을 실시하였다. 심바스타틴의 혈장 중의 농도를 정량하기 위하여 발리데이션된 LC/MS/MS를 사용하였다. 채혈 시간은 투약 전 및 투약 후 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 10, 12 시간에 걸쳐 총 12시점에 걸쳐 시행하였다. 생물학적 동등성을 판정하기 위한 파라미터로 12시간까지의 혈장 중 농도곡선 하 면적 ()과 최고 혈중 농도()를 사용하였다. 12시간 까지의 혈중 농도 곡선 하 면적의 기하 평균은 (시험약)과 (대조약)으로 나타났다. 최고 혈중 농도의 경우 각 각 5.08 ng/ml(시험약)과 5.20 ng/ml(대조약)으로 관찰 되었다. 의 경우 로그변환한 평균치 차의 신뢰구간이 log0.8510 - log1.1694이었고, 의 경우 log0.8176 - log1.1649로 계산되어 두 항목 모두 log0.8-log1.25이어야 한다는 식품의약품 안전청과 FDA의 기준을 모두 만족시켰다. 이상의 결과를 종합하면 시험약 엘바스타 정 20mg은 대조약 조코정 20 mg에 대하여 생물학적 동등한 것으로 판정되었다.

A simple HPLC method was employed for the determination of pentoxifylline in human serum. After addition of internal standard (IS, 50 uL of 3 ug/mL chloramphenicol methanol solution) into the serum sample, the drug and IS were extracted by dichloromethane. Following a 1-min vortex-mixing and a 15-min centrifugation at 3500 게m, the organic phase was transferred and evaporated to dryness under a vacuum. The residue was reconstituted with 120 of mobile phase and 50 was injected into C18 column with a mobile phase composed of 0.034 M phosphoric acid adjusted to pH 4 with 10 M NaOH and acetonitrile (75:25, v/v). The samples were detected using an ultraviolet detector at 273 nm. The method was simple, specific and validated with a limit of 10 ng/mL. Intra- and inter-day precision and accuracy were acceptable for all quality control samples including the lower limit of quantification. The applicability of this method was evaluated by analysis of human serum after oral administration of a single 400 mg dose to 8 healthy subjects. The pharmacokinetic parameters for pentoxifylline in human subjects were calculated using WinNonlin program. As a result, and were , ng/mL, hr and hr, respectively. Based on the results, this validated method appears to be useful fur the pharmnacokinetic study of pentoxifylline in humans.

The purpose of this study is to investigate the effect of aspirin on the pharmacokinetics of pranoprofen by oral coadministration of pranoprofen (5 mg/kg) with aspirin (5, 10 and 20 mg/kg) in Sprague-Dawley rats. After oral coadministration of pranoprofen with aspirin, the area under the plasma concentration-time curves (AUC) of pranoprofen was increased significantly by 10 mg/kg (p<0.05) and 20 mg/kg (p<0.01) of aspirin coadministration, and peak concentrations () of pranoprofen was increased significantly by coadministration of 20 mg/kg aspirin (p<0.05) compared to pranoprofen alone. Relative bioavailabilities (RB) of pranoprofen in coadmistration were higher (from 1.42 to 1.67 fold) than control. The half-lives () of pranoprofen in coadministration were increased significantly (p<0.05) by 20-mg/kg aspirin. Based on these results, we might be considered that the pharmacokinetics of pranoprofen would be affected by coadministration of aspirin, by inhibit its metabolism in the liver and the tubular secretion of the kidney with the same acidic property. It should take into consideration in dosage regimen of pranoprofen when coadministration of pranoprofen with aspirin in treatment of rheumatoid arthritis.

The aim of this study is to investigate the effect of naringin on the pharmacokinetics of tamoxifen in rats. Tamoxifen (10 mg/kg) was administered orally 0.5 h and 3 days after oral administration of naringin (5 mg/kg). The plasma concentrations of tamoxifen were increased significantly tv naringin compared to control. Absorption rate constant () of tamoxifen with naringin was increased significantly compared to that of the control. The areas under the plasma concentration-time curve (AUC) and the peak concentrations () of tamoxifen with naringin were significantly higher than those of the control. Consequently, the relative bioavailability (R.B) of tamoxifen with naringin was 2-3-fold higher than the control, and absolute bioavailability (A.B) of tamoxifen were significantly higher (p<0.05 with coadministration, p<0.01 with pretreatment) than those of the control. The increased bioavailability of tamoxifen in rats with naringin might be associated with the inhibition by naringin of an efflux pump P-glycoprotein and the first-pass metabolizing enzyme CYP3A4.

This study was designed to establish a strategy for the bioequivalence study of doxifluridine, an anticancer drug, in dogs instead of cancer patients. Although the results from animals may not occur in the same manner from human, those would be worth enough in terns of the bioequivalence. As for critically ill population such as cancer patients, bioequivalence studies in animals bring many advantages. Six healthy Beagle dogs were selected on the basis of hematology and blood chemistry test. After an over night fast, 200 mg of doxifluridine was orally administered, and blood was serially taken up to 12 hours. Plasma concentration of doxifluridine was measured using a newly validated bioanalytical method by a HPLC coupled tandem mass spectrometry. Time course of plasma doxifluridine concentration was analyzed with non-compartmental and compartmental approaches. Consequently, we represented hematology and blood chemistry database for the selection of healthy Beagle dogs, and suggested a sensitive and validated analytical method of doxifluridine, as well as a study design for the bioequivalence of doxifluridine in dogs.