The Effect of Herbal Medicine Baicalin on Pharmacokinetics of Rosuvastatin, Substrate of Organic Anion-transporting Polypeptide 1B1

Abstract

The aim of this study was to explore potential herb–drug interaction between baicalin and rosuvastatin, a typical substrate for organic anion‐transporting polypeptide 1B1 (OATP1B1) related to different OATP1B1 haplotype groups. Eighteen unrelated healthy volunteers who were CYP2C9*1/*1 with different OATP1B1 haplotypes (six OATP1B1*1b/*1b, six OATP1B1*1b/*15, and six OATP1B1*15/*15) were selected to participate in this study. Rosuvastatin (20 mg orally) pharmacokinetics after coadministration of placebo and 50‐mg baicalin tablets (three times daily orally for 14 days) were measured for up to 72 h by liquid chromatography–mass spectrometry in a two‐phase randomized crossover study. After baicalin treatment, the area under the plasma concentration–time curve (AUC)_(0–72) and AUC_(0–∞) of rosuvastatin decreased by 47.0±11.0% (P=0.001) and 41.9±7.19% (P=0.001) in OATP1B1*1b/*1b, 21.0±20.6% (P=0.035) and 23.9±8.66% (P=0.004) in OATP1B1*1b/*15, and 9.20±11.6% (P=0.077) and 1.76±4.89% (P=0.36) in OATP1B1*15/*15, respectively. Moreover, decreases of both AUC_(0–72) and AUC_(0–∞) of rosuvastatin among different haplotype groups were significantly different (P=0.002 and OATP1B1 haplotype–dependent manner. Clinical Pharmacology & Therapeutics (2008) 83, 3, 471–476.doi:10.1038/sj.clpt.6100318