Refametinib is a potent, selective, allosteric MEK1/MEK2 inhibitor with IC50s of 19 nM and 47 nM, respectively.
Description :
A potent, non–ATP-competitive, highly selective, allosteric inhibitor of MEK1/2 with IC50 of 19/47 nM respectively; inhibits anchorage-dependent growth of human cancer cell lines harboring the gain-of-function V600E BRAF mutant with GI50 of 67-89 nM; exhibits complete suppression of ERK phosphorylation at fully efficacious doses in mice and orally bioactive.
Liver Cancer
RDEA119 is selectively bound directly to an allosteric pocket in the MEK1/2 enzymes, and highly efficacious at inhibiting cell proliferation in several tumor cell lines, including A375, SK-MEI-28, Colo205, HT-29 and BxPC3. RDEA119 inhibits anchorage-dependent growth of human cancer cell lines harboring the gain-of-function V600E BRAF mutant with GI50 values ranging from 67 to 89 nM. Under anchorage-independent conditions, GI50 values for all cell lines tested are similar (40-84 nM). RDEA119 shows a tissue selectivity that reduces its potential for central nervous system–related side effects. [1] RDEA119 potently inhibits the proliferation of the 4 cell lines that harbored BRAF mutation but has no or modest effects on the other 4 cells that harbored wild-type BRAF (IC50 of 0.034-0.217 μM vs. 1.413-34.120 μM). This inhibitory effect of RDEA119 in selected cell lines OCUT1 (BRAF V600E(+), PIK3CA H1047R(+)) and SW1376 (BRAF V600E(+)) is enhanced by combination with the mTOR inhibitor, temsirolimus. RDEA119 and temsirolimus also show synergistic effects on autophagic death of OCUT1 and KAT18 cells selectively tested. [2]
Refametinib (RDEA119, BAY 869766) is an orally available, potent, non-ATP-competitive, highly selective inhibitor of MEK1/2, which is active in human tumor xenograft models and is well tolerated within the therapeutic exposure range in animals.The human melanoma A375 tumor xenograft is found to be sensitive to Refametinib treatment with 54% and 68% tumor growth inhibition (TGI) seen with 25 and 50 mg/kg/d administered orally on a once daily ×14 schedule. Significant tumor growth delay (TGD) and regressions are also observed in A375 tumors on this once-daily schedule. For example, five to eight complete or partial responses (CR/PR) and up to six tumor-free survivors (TFS) are observed. Administering Refametinib every other day at 100 mg/kg is less effective than daily dosing with either 25 or 50 mg/kg. When Refametinib is dosed on a twice-daily schedule, it is more effective than once-daily schedules[1].