[CAS NO. 1184843-57-9]  SAR-020106

SAR-020106 can enhance the antitumor effects of both irinotecan and gemcitabine in vivo with appropriate biomarker changes and minimal toxicity. Although having minimal oral bioavailability in mice (F = 5%), distribution of SAR-020106 following i.p. dosing (40 mg/kg) was sufficient to inhibit CHK1 in the tumors, as shown by inhibition of the irinotecan-induced CHK1 pS296 autophosphorylation. At doses giving inhibition of CHK1 activity in vivo, the selective CHK1 inhibitor SAR-020106 showed no single agent activity in the SW620 xenograft model, and tumors grew at similar rates to the vehicle-treated controls. When dosed (i.p.) in combination with irinotecan, SAR-020106 was observed to potentiate the antitumor activity of the genotoxic drug in the SW620 xenograft model.