ATM Inhibitor-8 (Compound 10r) is a potent, selective, and orally active ATM inhibitor with anti-tumor activity, characterized by an IC50 value of 1.15 nM [1].

ATM Inhibitor-8 exhibits inhibitory activity against colorectal cancer cells (HCT116, SW620) and breast cancer cells (MCF-7) [1]. When combined with 4.22 μM Etoposide and 0.036 μM Irinotecan at a concentration of 200 nM, ATM Inhibitor-8 significantly reduces the viability of MCF-7 cells [1]. Additionally, at the same concentration, ATM Inhibitor-8 in conjunction with 0.22 μM Irinotecan decreases SW620 cell viability and inhibits clonal formation of SW620 cells at 0.02 μM [1].

ATM Inhibitor-8, when combined with Irinotecan (40 mg/kg), demonstrates a potent suppressive effect on tumor growth in the SW620 mouse model [1]. Moreover, ATM Inhibitor-8 (10 mg/kg, i.v.) exhibits favorable pharmacokinetic (PK) properties in Balb/c mice, as evidenced by its low plasma clearance, high plasma exposure, and excellent oral bioavailability [1].