Alectinib: a selective, next-generation ALK inhibitor for treatment of ALK-rearranged non-small-cell lung cancer.

Crizotinib was the first clinically available anaplastic lymphoma kinase (ALK) inhibitor, showing remarkable activity against ALK-rearranged non-small-cell lung cancer (NSCLC). Despite initial responses, acquired resistance to crizotinib inevitably develops, with the brain being a common site of relapse. Alectinib is a highly selective, next-generation ALK inhibitor with potent inhibitory activity also against ALK mutations conferring resistance to crizotinib, including the gatekeeper L1196M substitution. In a Phase I/II study from Japan, alectinib was found to be highly active and safe in crizotinib-naïve, ALK-rearranged NSCLC patients. Alectinib also demonstrated promising antitumor activity in crizotinib-resistant patients, including those with CNS metastases. Based on these data, the drug received Breakthrough Therapy Designation by the US FDA and has been recently approved in Japan for the treatment of ALK-positive, advanced NSCLC patients. However, patients may eventually develop resistance to alectinib, highlighting the need for novel therapeutic strategies to further improve the management of ALK-rearranged NSCLC.