Ceritinib, alectinib, brigatinib, and ensartinib are second-generation ALK inhibitors, and lorlatinib is a third-generation ALK inhibitor, and all have been used to treat patients with ALK+ lung cancer.[3] ALK inhibitors have been shown to improve PFS and OS compared with standard first-line therapy of pemetrexed plus platinum-based chemotherapy.[5] However, eventual drug resistance is common with crizotinib, while second- and third-generation ALK inhibitors can also improve PFS and OS of patient. This evidence concerns the gene ALK and lung cancer.