Definition

The methanesulfonic acid salt form of FWD1509, an orally bioavailable, irreversible, small molecule, mutant-selective inhibitor of epidermal growth factor receptor (EGFR), with potential antineoplastic activity. Upon oral administration, EGFR mutant-selective inhibitor FWD1509 MsOH targets, binds to, and inhibits the activity of EGFR with exon20 insertion mutations, as well as L858R, exon19del and T790M mutations, thereby preventing EGFR-mediated signaling. This may both induce cell death and inhibit tumor growth in EGFR-overexpressing tumor cells. EGFR, a receptor tyrosine kinase mutated in many tumor cell types, plays a key role in tumor cell proliferation and tumor vascularization. FWD1509 MsOH is able to cross the blood-brain barrier (BBB).