Pharmacokinetics and Relative Bioavailability of Sustained-Release Alfzosin Hydrochloride Capsules in Healthy Beagle Dogs

OBJECTIVE To study the pharmacokinetics and relative bioavailability of the sustained-release alfuzosin hydrochloride capsules in healthy Beagle dogs.METHODS Following a single oral dose of the sustained-release alfuzosin hydrochloride capsules(test formulation) and conventional tablets(reference formulation) to each of the 6 healthy beagle dogs in a randomized crossover design,the plasma levels of the active drugs at different-time points were determined by HPLC and the plasma concentration-time curves of these formulations were obtained.The pharmacokinetic parameters as well as the relative bioavailability were analyzed.RESULTS The t2max values of the test formulation and reference formulation were(1.42±0.49) and(0.79±0.19) h.The ρ2max values were(323.92±70.82) and(508.31±120.62) μg·L2-1,and the AUC20-t were(1 082.99±290.75) and(1 174.56±336.31) μg·h·L2-1,respectively.The relative bioavailability of the test formulation was found to be(92.20±14.94)% compared with the reference formulation.The variance analysis showed no significant difference between the test and reference formulation in periods and formulations(P0.05),but significant difference was obtained in subjects.The 90% confidence interval of AUC20-t of the test formulation was 82.5%~108.2 %,compared with the reference formulation.CONCLUSION Compared with the alfuzosin hydrochloride conventional tablets,the sustained-release alfuzosin hydrochloride capsules have longer action time in dogs and similar relative bioavailability.