Evaluation of bioequivalence assessment after single dose theophylline sustained release capsules in healthy volunteers

OBJECTIVE:To evaluate the bioequivalence assessment of theophylline sustained release capsules in healthy volunteers.METHODS:A reversed phase high performance liquid chromatography (RP HPLC) method was established for the determination of theophylline in plasma after a single oral dose of 200mg domestic theophylline sustained release capsules and imported theophylline sustained release capsules in a randomized crossover design. The detector was operated at UV 273nm.RESULTS:The dynamic course of theophylline plasma concentrations conformed to a one compartment open model with a 3P87 program and the main pharmacokinetic parameters after a single oral dose of 200mg domestic sustained release capsules and imported sustained release capsules were as follows: C max were (5 12±0 74)mg/L and (5 14±0 63)mg/L, t max were (5 4±1 0)h and (5 3±1 1)h, MRT were (17 79±1 48)h and (17 61±1 78)h, t 1/2 were (10 55±0 75)h and (10 59±1 10)h, AUC 0-36 were (85 33±10 56)mg·h/L and (86 26±8 80)mg·h/L,respectively.CONCLUSIONS:The relative bioavailability of domestic theophylline sustained release capsules is (98 9±6 4)%.The results of statistical analysis for C max ,AUC 0-36 and AUC 0-∞ showed that domestic sustained release capsules and imported sustained release capsules were bioequivalent.