While the most common TRAEs were EGFR TKI class-related toxicities (diarrhea, rash/acne and stomatitis) and were not unexpected, the overall rate of grade ≥ 3 TRAEs was 58% compared with 31–49% in the LUX Lung 3, 6 and 7 studies (diarrhea: 5–14%; rash/acne: 9–16%; stomatitis: 4–9%). Here, EGFR is linked to stomatitis.