DNA-directed DNA polymerase x TYMS

Main research purpose: According to the relevant provisions of bioequivalence test, brivudine tablets (trade name: Zostex, specification: 125 mg/tablet) produced by Berlin-Chemie AG were selected as the reference preparation, and the test preparation brivudine tablets (specification: 125 mg/tablet) provided by China Resources Double Crane Pharmaceutical Co., Ltd. and produced by China Resources Double Crane Limin Pharmaceutical (Jinan) Co., Ltd. were subjected to human bioequivalence test for fasting and postprandial administration, to compare whether the absorption rate and degree of the drug in the test preparation were within the acceptable range with the reference preparation, and to compare the bioequivalence of the two preparations under fasting and postprandial administration conditions. Secondary research purpose: To observe the safety of oral administration of the test preparation brivudine tablets (specification: 125 mg/tablet) and the reference preparation brivudine tablets (trade name: Zostex, specification: 125 mg/tablet) in healthy volunteers.

To investigate the pharmacokinetic characteristics of brivudine tablets (test preparation, specification: 125 mg) produced by Hunan Warner Pharmaceutical Co., Ltd. and brivudine tablets (reference preparation, trade name: Zostex®, specification: 125 mg) produced by Berlin-Chemie AG after a single oral administration under fasting and postprandial conditions in healthy subjects, evaluate the bioequivalence between the two preparations, and provide a basis for the registration application of the test preparation.

Evaluate the fasting bioavailability of the two preparations, obtain the intra-individual variability of the reference preparation, which is used to calculate and adjust the sample size of the formal test, and verify and determine the formal test process, blood collection points and sample number to determine whether to use the average bioequivalence evaluation method corrected by the reference preparation. Calculate the overall coefficient of variation of the test and reference preparations after meals, which is used to calculate and adjust the sample size of the formal test, and verify and improve the formal test process, blood collection points and sample number.