Bioequivalence study of a valsartan tablet and a capsule formulation after single dosing in healthy volunteers using a replicated crossover design

Two formulations of valsartan (Diovan), 320 mg tablets and marketed 160 mg capsules, were evaluated for bioequivalence after single dosing.The study was designed as a single-center, open-label, 2-treatment, 3-period, repeated-measure (replicated), randomized crossover comparison in 40 healthy volunteers, all of whom completed the study successfully. Valsartan was determined in plasma by HPLC with fluorescence detection after solid-phase extraction.Comparing the new 320 mg tablet with 2 x 160 mg of the marketed valsartan capsules taken at the same time, the ratios of the least square means for AUC(0-t), AUC(all), AUC(0-infinity) and Cmax were 1.11, 1.10, 1.10 and 1.09, respectively. The 90% confidence intervals of the AUC and Cmax parameters were within the range of 0.80-1.25.Bioequivalence of the new 320 mg tablet with 2 marketed 160 mg capsules was demonstrated.