Description
CEP-32496 is a highly potent inhibitor of BRAF(V600E/WT) and c-Raf with Kd of 14 nM/36 nM and 39 nM, modest potent to Abl-1, c-Kit, Ret, PDGFRβ and VEGFR2, respectively; insignificant affinity for MEK-1, MEK-2, ERK-1 and ERK-2. Phase 1/2.
Storage
2 years -20 centigrade Powder; 2 weeks 4 centigrade in DMSO; 6 months -80 centigrade in DMSO.
Targets
BRAF(V600E), BRAF(WT), c-Raf, Abl-1, CSF-1R
IC50
14 nM; 36 nM; 39 nM; 3 nM; 9 nM
Molecular Formula
C24H22F3N5O5
Chemical Name
Urea, N-[3-[(6,7-dimethoxy-4-quinazolinyl)oxy]phenyl]-N-[5-(2,2,2-trifluoro-1,1-dimethylethyl)-3-isoxazolyl]-
Solubility
DMSO 9 mg/mL; Water <1 mg/mL; Ethanol <1 mg/mL
In vitro
CEP-32496 inhibits A375 cell (BRAFV600E) proliferation with EC50 of 78 nM. CEP-32496 exhibits more sensitive cytotoxicity for tumor cell lines (A375, SK-MEL-28, Colo-205, Colo-679, and HT-144) expressing mutant BRAF than those expressing wild-type BRAF (HCT116, Hs578T, LNCaP, DU145, and PC-3). CEP-32496 inhibits mitogen-activated protein (MAP)/extracellular signal-regulated (ER) kinase (MEK) phosphorylation (pMEK) in human melanoma (A375) and colorectal cancer (Colo-205) cell lines with IC50 of 78 nM and 60 nM, respectively.
In vivo
CEP-32496 exhibits good stability in mouse, dog, monkey, and human liver microsomal preparations with measured intrinsic clearance values of <23 (μL/min)/mg and t1/2 > 60 min in all assays. CEP-32496 (30 mg/kg, orally, BID) exhibits tumor stasis and a 40% incidence of partial tumor regressions (PRs) in Colo-205 xenograft mouse model, whereas the 100 mg/kg dose group exhibits both tumor stasis and an 80% incidence of PRs. CEP-32496 (30 mg/kg, orally, BID) leads to a 50% and 75% inhibition of normalized pMEK in tumor lysates at the 2 hours and 6 hours postdose time point, respectively, while a 55 mg/kg dose results in a 75% to 57% inhibition of pMEK at 2 hours through 10 hours post administration in Colo-205 xenograft mouse model. CEP-32496 is orally bioavailable in multiple preclinical species (>95% in rats, dogs, and monkeys). CEP-32496 (100 mg/kg) results in inhibition of pMEK and pERK and sustained tumor stasis and regressions in BRAF(V600E) colon carcinoma xenografts in nude mice.