Pharmacokinetics of tenofovir disoproxil fumarate capsule in Chinese volunteers

To investigate the pharmacokinetics of tenofovir disoproxil fumarate(TDF)capsule in Chinese volunteers. A phase I, 3-period study was performed in healthy Chinese subjects. 12 Healthy subjects received either single 300 mg, multiple 300 mg and single 600 mg doses of TDF under fasted conditions, or received single 300 mg doses under fed condition. For 300 mg and 600 mg single administration of TDF, the c_max data were(305. 4±96. 4)and(590. 0±149. 6)ng/mL, respectively, and the AUC_{0-72 h} data were(2 396±489)and(4 465±1 042)ng ·h/mL, respectively. In the dose range of 300-600 mg, tenofovir demonstrated linear pharmacokinetic characteristics in Chinese volunteers. No significant gender difference in the pharmacokinetic parameters was found. High fat food decreased the absorption rate of tenofovir, but increased its exposure. In the multiple-dose study at 300 mg dose for 7 consecutive days, the degree of fluctuation(DF)was 2. 7±0. 6, and the accumulation parameter(R_cmax)and(R_AUC)were 1. 3±0. 3 and 1. 7±0. 4, respectively. Compared with the single dose administration, an increased exposure of 70% in AUC_0-τ of tenofovir was observed after a multiple administration.