First macrocyclic 3-generation ALK inhibitor for treatment of ALK/ROS1 cancer: Clinical and designing strategy update of lorlatinib.

Non-small cell lung cancers (NSCLC) harboring anaplastic lymphoma kinase (ALK) gene rearrangements invariably develop resistance to 2-generation ALK inhibitors. Lorlatinib (PF-06463922) (6) is a 3-generation macrocyclic ALK-TKI that demonstrates many advantages over 2-generation ALK inhibitors. Lorlatinib has demonstrated decent kinase selectivity, promising pharmacokinetic profile, selective brain-penetration and strong antiproliferative activity in several ALK/ROS1-driven tumor models. The current review describes the activity spectrum, key events from discovery to clinical applications and the evidences that lorlatinib acts as an ALK/ROS1 inhibitor in clinical settings.