LY3009120

LY3009120 (DP-4978) is a pan RAF inhibitor which inhibits BRAF^V600E, BRAF^WT and CRAF^WT with IC₅₀s of 5.8, 9.1 and 15 nM, respectively. IC50 & Target:IC50: 5.8 nM (BRAF^V600E), 9.1 nM (BRAF^WT), 15 nM (CRAF^WT)^[1] In Vitro: In the whole-cell based KiNativ assay, LY3009120 shows affinity to each RAF isoform with the IC₅₀ of 44, 31-47 and 42 nM for ARAF, BRAF and CRAF respectively. LY3009120 exhibits anti-proliferative effects on cell lines harboring BRAF^V600E, KRAS^G13 and KRAS^G12 mutations. LY3009120 (1 μM) inhibits the phosphorylation of both MEK1/2 and ERK1/2 in cell lines with high basal levels of pMEK1/2 and pERK1/2 (RKO and HCT 116)^[1]. LY3009120 shows inhibitory effect on tumor cells such as BxPC-3, NCI-H2405 and OV-90 cell lines. LY3009120 (0.01 μM) demonstrates potent and dose-dependent inhibition of phospho-MEK and ERK in all three cell lines. LY3009120 demonstrates a concentration-dependent cell growth inhibition with IC₅₀ values of 0.04, 0.087, and 0.007 μM against H2405, BxPC-3, and OV-90 cells, respectively^[2]. LY3009120 inhibits BRAF^WT, CRAF^WT, BRAF^V600E, and BRAF^V600E+G468A with the IC₅₀ values of 9.1, 15, 5.8, and 17 nM, respectively. LY3009120 induces BRAF-CRAF dimerization but inhibits the phosphorylation of downstream MEK and ERK. LY3009120 also inhibits various forms of RAF dimers including BRAF or CRAF homodimers^[3]. LY3009120 gives only very minor activation at very low doses, with near complete inhibition of phospho-ERK at concentrations above 100 nM^[4]. In Vivo: LY3009120 (20 mg/kg bid) displays significant activity in in vivo BRAF^mut and KRAS^mut CRC xenograft models. In Colo 205 xenografts (BRAF^mut), LY3009120 results in statistically significant tumor regression, while treatment of HCT 116 xenografts (KRAS^mut) results in statistically significant inhibition of tumor growth. LY3009120 treatment reduces pMEK1/2 in all HT-29 xenografts and reduces pERK1/2 in the majority of HT-29 xenografts^[1]. LY3009120 (15 or 30 mg/kg) achieves almost complete tumor growth regression, and inhibits downstream phospho-MEK and ERK by approximately 70% and 60%, respectively, in the H2405 model^[2].