Theliatinib (Xiliertinib) tartrate is a potent and highly selective EGFR inhibitor, displaying ATP-competitive and orally active properties. It exhibits promising efficacy with a K_i of 0.05 nM and an IC_50 of 3 nM for EGFR, alongside a specific IC_50 of 22 nM against the EGFR T790M/L858R mutant. Notably, Theliatinib demonstrates over 50-fold selectivity for EGFR compared to other kinases, underscoring its targeted action in inhibiting EGFR.