The results of the phase I trial conducted on advanced or metastatic non-small cell lung cancer (NSCLC) patients bearing EGFR-activating mutations, as well as HR-positive, HER2-negative breast cancer (BC) that had previously received third-generation tyrosine kinase inhibitors (TKIs) or CDK4/6 inhibitors and at least one line of chemotherapy were recently presented at the American Society of Clinical Oncology (ASCO) 2024 Annual Meeting held in Chicago. Here, CDK4 is linked to breast cancer.