Gefitinib

Gefitinib was found to be a potent inhibitor of EGFR kinase (Ki = 0.40 nM), but much weaker against ErbB-2 kinase (Ki = 870 nM) and ErbB-4 kinase (Ki = 1.1 µM). The IC₅₀ values for Gefitinib to inhibit HT-29 and LoVo cell growth were 23.6 - >100 µM and 7.3 - 48.5 µM, respectively, when the exposure times are from 18 hours to 3 days. The IC₅₀ values of Gefitinib to the breast cancer cell lines BT20, HCC1937, MDA-MB-231, BT474, and SKBR3 are 15.5±1.4, 8.4±1.5, 20.7±1.1, 0.25±0.05, 0.88±0.31 µM, respectively