RG14620 is an EGFR inhibitor with an IC₅₀ of 3 μM. IC50 & Target: IC50: 3 μM (EGFR)^[1] In Vitro: RG14620 inhibits colony formation (IC₅₀=3 μM) and DNA synthesis (IC₅₀=1 μM) by HER 14 cells, which are stimulated by 50 ng/mL EGF, in a dose-dependent manner. RG14620 also suppresses colony formation(IC₅₀=4 μM) and DNA synthesis (IC₅₀=1.25 μM) by EGF-stimulated MH-85 cells in a dose-dependent manner. The growth-inhibitory effect of RG14620 irreversible^[2]. In Vivo: RG14620, at a dose of 200 g/mouse/day inhibits H-85 tumor growth in nude mice. Mice show less cachexia and hypercalcemia, eat more food, and are more active than untreated MH-85 tumor-bearing animals^[2].