[CAS NO. 1258392-53-8]  AZD5582

After AZD5582 treatment, tumor growth and weight decrease, whereas cleaved caspase 3 expression increases in Panc-1-derived xenograft model. When administered intravenously to MDA-MB-231 xenograft-bearing mice, AZD5582 results in cIAP1 degradation and caspase-3 cleavage within tumor cells and causes substantial tumor regressions following two weekly doses of 3.0 mg/kg. Following a modest 0.5 mg/kg intravenous bolus dose of AZD5582 in mice, unbound plasma levels remain above the concentrations at which apoptosis induction and cell death are observed in MDA-MB-231 cells over the course of several hours. Although cIAP1 degradation happens very quickly upon exposure to AZD5582 in vivo, apoptosis induction (as measured by the amount of cleaved caspase-3) takes longer to reach a maximal effect. A single agent AZD5582 does not exhibit broad-based cytotoxicity but instead should be employed in selected tumor settings expected to be sensitive to IAP inhibitors or in rational combinations with other targeted therapies. The dihydrochloride salt of AZD5582 has sufficient aqueous solubility (>7 mg/mL at pH 4−6) to enable formulation for intravenous administration at the projected efficacious doses. With respect to chemical stability, AZD5582 is found to be photostable and hydrolytically stable between pH 4−6, although some amide hydrolysis is observed under strongly acidic (pH < 1) and basic (pH > 8) conditions. In addition, the compound is stable in the plasma of multiple species, with no compound degradation observed after several hours under physiological conditions.