In the subgroup with women, < 65 years, ECOG (Eastern Cooperative Oncology Group) 0–1, nonsmoker, EGFR 21 mutation, and positive EGFR T790M mutation, PFS was significantly longer in the Chemo + IO group….Pembrolizumab combined with chemotherapy may improve PFS and survival compared to platinum-based chemotherapy alone in pre-treated EGFR-mutant NSCLC patients after EGFR-TKI therapy discontinuation.