CYP isoform-selective substrates
In vitro data indicate that regorafenib is a competitive inhibitor of the cytochromes CYP2C8
(Ki value of 0.6 µM), CYP2C9 (Ki value of 4.7 µM), CYP2B6 (Ki value of 5.2 µM) at
concentrations which are achieved in vivo at steady state (peak plasma concentration of 8.1 µM).
The in vitro inhibitory potency towards CYP3A4 (Ki value of 11.1 µM) and CYP2C19 (Ki value
of 16.4 µM) was less pronounced.