Therapeutic resistance in ROS1-rearranged NSCLC has largely been studied in the context of crizotinib therapy but the resistance pattern has begun to emerge with the recent FDA approval of the type I ROS1-TKIs entrectinib and the National Comprehensive Cancer Network (NCCN) guideline recommendation of lorlatinib [41, 42]. The gene discussed is ROS1; the disease is non-small cell lung carcinoma.