PHA-793887

Intravenous injection once daily

A2780 cells

A Phase I clinical trial of PHA-793887 for advanced/metastatic solid tumors has been terminated.

PHA-793887 is a novel and potent inhibitor of CDK2, CDK5 and CDK7 with IC50 of 8 nM, 5 nM and 10 nM, respectively.

Multi-CDKs inhibitor.

8 nM, 8 nM, 8 nM, 8 nM, 8 nM, 8 nM

PHA-793887 (10–30 mg/kg) shows good efficacy in the human ovarian A2780, colon HCT-116, and pancreatic BX-PC3 carcinoma xenograft models. [1] PHA-793887 (20 mg/kg) is effective in xenograft models of K562 and HL60 cells, primary leukemic disseminated model, and a high-burden disseminated ALL-2 model derived from a relapsed Philadelphia-positive acute lymphoid leukemia patient. [2]

[3], CDK Kinase Assay, The biochemical activity of compounds is determined by incubation with specific enzymes and substrates, followed by quantitation of the phosphorylated product. PHA-793887 (1.5 nM–10 uM) is incubated for 30 90 min at room temperature in the presence of ATP/33P-gamma-ATP mix, substrate, and the specific enzyme (0.7 100 nM) in a final volume of 30 uL of kinase buffer, using 96 U bottom plates. After incubation, the reaction is stopped and the phosphorylated substrate is separated from nonincorporated radioactive ATP using SPA beads, Dowex resin, or Multiscreen phosphocellulose filter as follows: (1) For SPA Assays. The reaction is stopped by the addition of 100 uL of PBS + 32 mM EDTA + 0.1% Triton X-100 + 500 uM ATP, containing 1 mg of streptavidin-coated SPA beads. After 20 min of incubation for substrate capture, 100 uL of the reaction mixture is transferred into Optiplate 96-well plates containing 100 uL of 5 M CsCl, left to stand for 4 hours to allow stratification of beads to the p of the plate, and counted using TopCount to measure substrate-incorporated phosphate. (2) For Dowex Resin Assay. An amount of 150 uL of resin/formate, pH 3.00, is added to stop the reaction and capture unreacted 33P-gamma-ATP, separating it from the phosphorylated substrate in solution. After 60 min of rest, 50 uL of supernatant is transferred to Optiplate 96-well plates. After the additon of 150 uL of Microscint 40, the radioactivity is counted in the TopCount. (3) For Multiscreen Assay. The reaction is stopped with the addition of 10 uL of EDTA (150 mM). An amount of 100 uL is transferred to a MultiScreen plate to allow substrate binding to phosphocellulose filter. Plates are then washed three times with 100 uL of H2PO4 (75 mM) filtered by a MultiScreen filtration system, and dried. After the additon of 100 uL of Microscint 0, radioactivity is counted in the TopCount. IC50 values are obtained by nonlinear regression analysis.

361, 48

DMSO 72 mg/mL, Water <1 mg/mL, Ethanol 72 mg/mL