The drug interaction potential of daprodustat when coadministered with pioglitazone, rosuvastatin, or trimethoprim in healthy subjects

This study was conducted to evaluate the likelihood of daprodustat to act as a perpetrator in drug-drug interactions (DDI) with the CYP2C8 enzyme and OATP1B1 transporter using the probe substrates pioglitazone and rosuvastatin as potential victims, respectively. Additionally, this study assessed the effect of a weak CYP2C8 inhibitor, trimethoprim, as a perpetrator of a DDI with daprodustat. This was a two-part study: Part A assessed the effect of coadministration of daprodustat on the pharmacokinetics of pioglitazone and rosuvastatin in 20 subjects; Part assessed the coadministration of trimethoprim on the pharmacokinetics of daprodustat in 20 subjects. Coadministration of 100 mg of daprodustat with pioglitazone or rosuvastatin had no effect on the plasma exposures of either probe substrate. When trimethoprim was coadministered with 25-mg daprodustat plasma daprodustat AUC and C-max increased by 48% and 28%, respectively. Additionally, AUC and C-max for the metabolite GSK2531401 were decreased by 32% and 40%, respectively. C-max for the other metabolites was slightly decreased (similar to 8-15%) but no changes in AUC were observed. As 100-mg daprodustat exceeds the planned top therapeutic dose, interaction potential of daprodustat as a perpetrator with substrates of the CYP2C8 enzyme and OATP1B1 transporters is very low. Conversely, daprodustat exposure (AUC and C-max) is likely to increase moderately with coadministration of weak CYP2C8 inhibitors.