Pharmacokinetics and bioequivalence of atorvastatin calcium tablets in healthy male Chinese volunteers / 中华心血管病杂志

ABSTRACT

<p><b>OBJECTIVE</b>To compare the bioequivalence and pharmacokinetics of national made and imported atorvastatin in healthy male Chinese volunteers after single oral administration.</p><p><b>METHODS</b>This randomized sequence, open-label, two-period crossover study with a one-week washout period between doses was performed in 24 fasting healthy Chinese males. They were randomly assigned to receive 20 mg of either the test (national made) or reference (imported) formulation orally. The blood samples were collected over a 72-hour period. Plasma concentrations of parent atorvastatin (AT), ortho-hydroxy-atorvastatin (o-OAT) and para-hydroxy-atorvastatin (p-OAT) were simultaneously determined using the validated liquid chromatography-tandem mass spectrometry method, the bioequivalence was also evaluated throughout the study.</p><p><b>RESULTS</b>The main pharmacokinetic parameters of test and reference formulations were as follows the values of C(max) for AT were (10.6 ± 11.9) µg/L and (10.6 ± 9.8) µg/L, t(1/2z) were (11.4 ± 3.9) h and (11.4 ± 5.3) h, AUC(0-t) were (54.2 ± 37.4) µg×h(-1)×L(-1) and (51.7 ± 34.1) µg×h(-1)×L(-1), respectively. The values of C(max) for o-OAT were (7.8 ± 4.5) µg/L and (7.6 ± 4.3) µg/L, t(1/2z) were (12.3 ± 4.2) h and (11.9 ± 3.4) h, AUC(0-t) were (96.8 ± 48.2) µg×h(-1)×L(-1) and (92.3 ± 44.4) µg×h(-1)×L(-1), respectively. The values of C(max) for p-OAT were (0.5 ± 0.4) µg/L and (0.4 ± 0.3) µg/L, t(1/2z) were (18.4 ± 12.4) h and (23.3 ± 17.8) h, AUC(0-t) were (15.9 ± 12.3) µg×h(-1)×L(-1) and (13.8 ± 8.11) µg×h(-1)×L(-1), respectively. The relative bioavailability of AT and o-OAT in test formulation were (105.3 ± 20.7)% and (107.8 ± 23.2)%, respectively. The 90% confidence interval of the test/reference geometric mean ratios of AUC(0-t) for AT and o-OAT were (97.7 - 110.5)% and (98.3 - 111.3)%, C(max) for AT and o-OAT were (75.8 - 114.0)% and (90.6 - 122.9)%, they were all located within the bioequivalence criteria range (80% - 125% for AUC, and 70% - 143% for C(max)).</p><p><b>CONCLUSION</b>The result demonstrated that two formulations were bioequivalent.</p>