VE-821 NLT 98%

VE-821 is a potent ATP-competitive inhibitor of ATR with K_i/IC₅₀ of 13 nM/26 nM. IC50 & Target: Ki: 13 nM (ATR)^[1]
IC50: 26 nM (ATR)^[2] In Vitro: VE-821 shows excellent selectivity for ATR with minimal cross-reactivity against the related PIKKs ATM, DNA-PK, mTOR and PI3Kγ (K_is of 16 μM, 2.2 μM, >1 μM and 3.9 μM, respectively) and against a large panel of unrelated protein kinases^[1]. VE-821 (compound 27) also inhibits ATM and DNA-PK wirh IC₅₀ of >8 μM, and 4.4 μM, respectively^[2]. VE-821 significantly enhances the sensitivity of PSN-1, MiaPaCa-2 and primary PancM pancreatic cancer cells to radiation and Gemcitabine under both normoxic and hypoxic conditions. ATR inhibition by VE-821 leads to inhibition of radiation-induced G₂/M arrest in cancer cells. In both PSN-1 and MiaPaCa-2 cells, 1 µM VE-821 inhibits phosphorylation of Chk1 (Ser 345) after treatment with Gemcitabine (100 nM), radiation (6 Gy) or both, at 2 h post-irradiation^[3].