NCIt definition : The tosylate salt form of NB003, an orally bioavailable inhibitor of specific mutated
forms of platelet-derived growth factor receptor alpha (PDGFR alpha; PDGFRa) and mast/stem
cell factor receptor c-Kit (SCFR; CD117), with potential antineoplastic activity.
Upon oral administration, ubavitinib specifically targets, binds to and inhibits specific
mutant forms of PDGFRa and c-Kit. This results in the inhibition of PDGFRa- and c-Kit-mediated
signal transduction pathways and the inhibition of proliferation in tumor cells that
express these PDGFRa and c-Kit mutants. PDGFRa and c-Kit, protein tyrosine kinases,
are upregulated or mutated in various tumor cell types; they play key roles in the
regulation of cellular proliferation and resistance to chemotherapy.;