Drug Interaction Report

GENERALLY AVOID: Coadministration with erdafitinib may increase the plasma concentrations of drugs that are substrates of the P-glycoprotein (P-gp) efflux transporter, resulting in increased toxicity of these drugs. In vitro, erdafitinib has been shown to be an inhibitor of P-gp. However, no pharmacokinetic data are available from drug interaction studies.

MANAGEMENT: Concomitant use of erdafitinib and P-gp substrates should generally be avoided. If concomitant use is required, administer erdafitinib at least 6 hours before or after administration of P-gp substrates with narrow therapeutic ranges.

GENERALLY AVOID: Grapefruit juice may significantly increase the plasma concentrations of orally administered everolimus. The mechanism is inhibition of CYP450 3A4 and P-glycoprotein activity in the gut wall by certain compounds present in grapefruit.

MANAGEMENT: Patients treated with everolimus should avoid consumption of grapefruit and grapefruit juice.