In vitro activity: In human whole blood from normal donors, Cerdulatinib affects BCR-mediated B-cell activation by dual inhibition of SYK and JAK. As a dual SYK/JAK inhibitor, Cerdulatinib significantly reduces cell viability in a subset of NHL cell lines, and induces apoptosis in BCR-signaling competent NHL cell lines.

Kinase Assay: Potency against purified SYK is determined by fluorescence resonance energy transfer. A broader panel of 270 purified kinases is surveyed in which PRT062070 is tested at a fixed concentration of 300 nM. [33P]-labeled substrate is measured after incubation of purified kinase with peptide substrate and [33P]ATP at the Km concentration for the kinase.

Cell Assay: Cell lines (Ramos RA-1, Daudi, Toledo, SU-DHL4 and SU-DHL6) are cultured in RPMI media supplemented with 10% fetal bovine serum. Cells are treated with the indicated concentrations of PRT062070, the SYK-selective inhibitor PRT060318, the pan-JAK inhibitor 1, a 1:1 combination of PRT060318 and JAK inhibitor 1, or vehicle control (0.5% dimethylsulfoxide) for 72 hours. Cell viability assays are performed using CellTiter Glo in 384-well plates. Cells are seeded at a density of 5000 cells per well.

J Pharmacol Exp Ther. 2014 Dec;351(3):538-48.