A recent breakthrough in the treatment of EGFR T790M mutant cancers occurred with the development of mutant selective pyrimidine based third-generation EGFR-TKIs, which include the WZ4002, CO-1686, osimertinib and HM61713 inhibitors which have demonstrated tumor responses in > 50% of patients harboring EGFR T790M mutation [11–14]. The gene discussed is EGFR; the disease is cancer.