Twenty-seven adult patients with ALK–rearranged advanced NSCLC with an ECOG PS ≤2 were enrolled into five cohorts to receive various dose combinations of ceritinib (range, 300–450 mg/day) and ribociclib (range, 100–300 mg/day)...Among the 27 evaluable patients, the overall response rate (ORR) was 37.0% (95% CI, 19.4–57.6) and median progression-free survival (mPFS) was 21.5 months (95% CI, 5.5–25.0). At RP2D, the ORR was 50.0%, disease control rate was 75%, and mPFS was 24.8 months (95% CI, 5.5–25.1)....Combination of ceritinib and ribociclib showed clinical activity with a manageable safety profile in patients with advanced ALK-rearranged NSCLC.