Cerdulatinib hydrochloride (PRT2070 hydrochloride) is an oral active, multi-targeted tyrosine kinase inhibitor with IC50 of 12 nM/6 nM/8 nM/0.5 nM and 32 nM for JAK1/JAK2/JAK3/TYK2 and Syk, respectively. Also inhibits 19 other tested kinases with IC50 less than 200 nM.

JAK2:6 nM, JAK1:12 nM, TYK2:0.5 nM, JAK3:8 nM, Syk:32 nM

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. [1]

In a rat collagen-induced arthritis model, Cerdulatinib (5 mg/kg p.o.) significantly improves inflammatory infiltrate within the synovium and the integrity of the articular cartilage. In addition, Cerdulatinib also blocks BCR-induced B-cell activation and splenomegaly in mice. [1]

Purified Kinase Assays: 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 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. (Only for Reference)