The FDA recommends rosuvastatin dosage reductions in Asian patients because pharmacokinetic studies have demonstrated an approximate two-fold increase in median exposure to rosuvastatin in Asian subjects when compared to Caucasian controls. Yet, no explanation for this ethnic difference has been confirmed. Here we show that rosuvastatin exposure in Asians and Whites does not differ significantly when all subjects are wildtype carriers for both Solute Carrier Organic anion transporter1B1 *1a and ATP Binding Cassette Subfamily G Member 2 c.421 transporters in a two arm, randomized, cross-over rosuvastatin pharmacokinetics study in healthy White and Asian volunteers. For single rosuvastatin doses, AUC0–48 were 92.5(±36.2) and 83.5(±32.2) ng/mL*hr and Cmax were 10.0(±4.1) and 7.6(±3.0) ng/mL for Asians and Whites, respectively. When transporters were inhibited by intravenous rifampin, rosuvastatin AUC0–48 and Cmax also showed no ethnic differences. Our study suggests that both SLCO1B1 and ABCG2 polymorphisms are better predictors of rosuvastatin exposure than ethnicity alone and could be considered in precision medicine dosing of rosuvastatin.

No abstract

The co-administration of rabeprazole with atazanavir resulted in significant decreases in atazanavir exposure. The addition of betaine HCl did not sufficiently mitigate the loss of ATV exposure observed during RAB-induced hypochlorhydria. Meal effects lead to a marked difference in the outcome of betaine HCl on atazanavir exposure than we previously reported for dasatanib under fasting conditions.

Here we address the potential difference in rosuvastatin pharmacokinetics in Asians vs. whites. Our prospective study, reported in this issue, shows no ethnic difference when all subjects are wild-type for OATP1B1 and BCRP. We argue that although our study may be under powered to prove no ethnic difference, and that further confirmatory study is required, the virtual clinical study analysis, also reported in this issue, does not contradict the results of our prospective clinical study and that previous retrospective analysis of clinical studies does not include enough relevant subjects to conclude that wild-type OATP1B1 and BCRP do still demonstrate ethnic differences.

No abstract