NCI-H1975-C797S derived-xenografts were treated with APG-1252, cisplatin/docetaxel or their combinations….Combination therapy with APG-1252 and cisplatin or docetaxel exhibited synergistic antitumor activity. APG-1252 plus docetaxel combination achieved 100% tumor partial regression (PR). Similar results were demonstrated in a patient-derived xenograft (PDX) tumor model derived from an osimertinib-resistant NSCLC patient harboring 19del-T790M-C797S mutations.