TAE684 (NVP-TAE684) is a potent and selective inhibitor of the anaplastic lymphoma kinase (ALK). It is primarily used in research settings to study ALK-driven cancers, particularly non-small cell lung cancer (NSCLC) and anaplastic large cell lymphoma (ALCL), where ALK gene rearrangements play a key role in tumor development. The compound demonstrates strong anti-tumor activity by blocking ALK phosphorylation and downstream signaling pathways such as STAT3, AKT, and ERK, leading to cell cycle arrest and apoptosis in ALK-positive cancer cells. Due to its high selectivity and efficacy in preclinical models, TAE684 has served as a critical tool compound for validating ALK as a therapeutic target and for guiding the development of clinically approved ALK inhibitors. It is not used in clinical practice but remains valuable in laboratory research for understanding resistance mechanisms, combination therapies, and the biology of ALK-dependent tumors.