Charles Rudin, MD, PhD of Memorial Sloan Kettering Cancer Center discusses Osimertinib, its real world toxicity issues and comparison with 1st generation TKIs. Osimertinib has less toxicity than the first generation EGFR TKIs. From the FLAURA study, numerical data suggests similar toxicity profile, with both rash and diarrhea being significant component. Gastrointestinal (GI) toxicity is a problem with persistent diarrhea, but the skin toxicity is substantially less.