PT  - JOURNAL ARTICLE
AU  - Minjee Kim
AU  - Janice K. Laramy
AU  - Afroz S. Mohammad
AU  - Surabhi Talele
AU  - James Fisher
AU  - Jann N. Sarkaria
AU  - William F. Elmquist
TI  - Brain Distribution of a Panel of Epidermal Growth Factor Receptor Inhibitors Using Cassette Dosing in Wild-Type and <em>Abcb1/Abcg2</em>-Deficient Mice
AID  - 10.1124/dmd.118.084210
DP  - 2019 Apr 01
TA  - Drug Metabolism and Disposition
PG  - 393--404
VI  - 47
IP  - 4
4099  - http://dmd.aspetjournals.org/content/47/4/393.short
4100  - http://dmd.aspetjournals.org/content/47/4/393.full
SO  - Drug Metab Dispos2019 Apr 01; 47
AB  - Tyrosine kinase inhibitors that target the epidermal growth factor receptor (EGFR) have had success in treating EGFR-positive tumors, including non–small-cell lung cancer (NSCLC). However, developing EGFR inhibitors that can be delivered to the brain remains a challenge. To identify optimal compounds for brain delivery, eight EGFR inhibitors [afatinib, 6-[4-[(4-ethylpiperazin-1-yl)methyl]phenyl]-N-(1-phenylethyl)-7H-pyrrolo[2,3-day]pyrimidin-4-amine (AEE788), [4-(3-chloro-2-fluoroanilino)-7-methoxyquinazolin-6-yl] (2R)-2,4-dimethylpiperazine-1-carboxylate (AZD3759), erlotinib, dacomitinib, gefitinib, osimertinib, and vandetanib] were evaluated for distributional kinetics using cassette dosing with the ultimate goal of understanding the brain penetrability of compounds that share the same molecular target in an important oncogenic signaling pathway for both primary brain tumors (glioblastoma) and brain metastases (e.g., NSCLC). Cassette dosing was validated by comparing the brain-to-plasma ratios obtained from cassette-dosing to discrete-dosing studies. The brain-to-blood partition coefficients (Kp,brain) were calculated following cassette dosing of the eight EGFR inhibitors. The comparison of Kp,brain in wild-type and transporter-deficient mice confirmed that two major efflux transporters at the blood-brain barrier (BBB), P-glycoprotein and breast cancer resistance protein, play a crucial role in the brain distribution of seven out of eight EGFR inhibitors. Results show that the prediction of brain distribution based on physicochemical properties of a drug can be misleading, especially for compounds subject to extensive efflux transport. Moreover, this study informs the choice of EGFR inhibitors, i.e., determining BBB permeability combined with a known target potency, that may be effective in future clinical trials for brain tumors.