Ichiro Ieiri, Shyohei Tsunemitsu, Kazuya Maeda, Yukie Ando, Noritomo Izumi, Miyuki Kimura, Naoe Yamane, Tsuyoshi Okuzono, Mariko Morishita, Naoki Kotani, Eri Kanda, Mariko Deguchi, Kyoko Matsuguma, Shunji Matsuki, Takeshi Hirota, Shin Irie, Hiroyuki Kusuhara, Yuichi Sugiyama
We investigated the mechanisms of ritonavir-mediated enhancement effect on the pharmacokinetics of saquinavir using in vivo probes for CYP3A4 (midazolam), p-glycoprotein (fexofenadine), and OATP1B1 (pravastatin) following oral micro/small dosing. A cocktail of the drugs (2 mg of saquinavir, 100 µg of each probe) was administered to eight healthy volunteers (phase 1), and then coadministered with 20 mg (phase 2) and 100 mg (phase 3) of ritonavir. Plasma concentrations of the drugs were measured by validated LC-MS/MS methods...
June 2013: Journal of Clinical Pharmacology