In order to develop a standard procedure for the evaluation of bioequivalence of ethosuximide, an assay method was developed and bioavailability of ethosuximide was evaluated in three different laboratories using this method. Three laboratories were C...
In order to develop a standard procedure for the evaluation of bioequivalence of ethosuximide, an assay method was developed and bioavailability of ethosuximide was evaluated in three different laboratories using this method. Three laboratories were College of Pharmacy, Sungkyunkwan University (principle investigator: Prof. Seok-Yong Lee, Ph.D.), Department of Pediatrics, Seoul Asan Medical Center (principle investigator: Prof. Young-Seo Park, M.D., Ph.D.) and College of Pharmacy, ChungAng University (principle investigator: Prof. Uy-Dong Sohn, Ph.D.) The HPLC method, developed to determine the concentration of ethosuximide in human plasma, was validated completely in those three laboratories with respect to specificity, linearity, accuracy, precision, sensitivity and recovery. Bioavailability of ethosuximide was determine with eight healthy male volunteers. The product used was "Zarontil Soft Capsules" containing 250 mg ethosuximide made by Korean United Pharm. After 500 mg ethosuximide was administrated orally, plasm was obtained at predetermined time intervals, and the concentration of the unchanged drug was determined using the developed HPLC method. Plasma concentration of ethosuximide as a function of time was calculated and pharmacokinetic parameters such as Cmax(maxium serum concentration), Tmax(time to reach maximum concentration), AUC(area under the serum concentration-time curve) and t1/2(elimination half-life) were determined. Based on the results of bioavailability tests in three different laboratories, a standard procedure for the evaluation of bioequivalence of ethosuximide was suggested.