Pathway Gefitinib Pathway, Pharmacokinetics

Representation of the candidate genes involved in the transportation and metabolism of gefitinib.
Gefitinib Pathway, Pharmacokinetics
clickable pathway icons


Gefitinib is an anilinoquinazoline compound with the chemical name 4-quinazolinamine, N-(3-chloro-4-flurophenyl)-7-methoxy-6-[3-(4-morpholinyl)propoxy]. Gefitinib inhibits receptor tyrosine kinases (TKs) including the epidermal growth factor recpetor (EGRF)-TK. Gefitinib also inhibits ATP-binding cassette transporter-mediated drug efflux, which in turn strongly increases the intracellular concentrations of co-administrated drug molecules that are transporter substrates.

After oral administration, gefitinib is widely distributed throughout the body. Gefitinib is metabolized in the liver by cytochrome P450s, primarily by CYP3A4, but CYP3A5 and CYP2D6 also play minor roles in gefitinib metabolism. In addition to its role as an ABC transporter inhibitor, gefitinib has also been implicated as an inhibitor of CYP2C19 and CYP2D6 activity. Therefore, gefitinib may inhibit the metabolism of co-administered drugs that are substrates of CYP2C19 and CYP2D6 and weakly inhibits the metabolism of substrates of CYP2C9, CYP3A4, and CYP1A2.

Authors: Tina Hernandez-Boussard, David Flockhart, Xing Jian Lou.
M. Whirl-Carrillo, E.M. McDonagh, J. M. Hebert, L. Gong, K. Sangkuhl, C.F. Thorn, R.B. Altman and T.E. Klein. "Pharmacogenomics Knowledge for Personalized Medicine" Clinical Pharmacology & Therapeutics (2012) 92(4): 414-417. Full text
If you would like to reproduce this PharmGKB pathway diagram, send an email to to request permission. In your request, include the name of the pathway diagram you would like to use and provide a description of the purpose.
Therapeutic Categories:
  • Anticancer agents

Entities in the Pathway

Genes (8)

Relationships in the Pathway

Arrow FromArrow ToControllersPMID
CYP1A1 CYP1A1 gefitinib
CYP2C19 CYP2C19 gefitinib
CYP2C9 CYP2C9 gefitinib
CYP2D6 CYP2D6 gefitinib
gefitinib M387783 CYP3A4, CYP3A5
gefitinib M523595 CYP2D6, CYP3A4
gefitinib M537194 CYP3A4, CYP3A5
gefitinib gefitinib ABCB1, ABCG2

Download data in TSV format. Other formats are available on the Downloads/LinkOuts tab.