Theliatinib (HMPL-309) is a highly potent EGFR inhibitor with Ki value of 0.05 nM against the wild type EGFR and IC50 values of 3 nM and 22 nM against EGFR and EGFR T790M/L858R mutant. It demonstrats 50 fold greater selectivity for EGFR compared to 72 other kinases.