Shaw AT, et al. - Researchers assessed anaplastic lymphoma kinase (ALK) mutations as well as the association between ALK mutation status and efficacy of lorlatinib in 198 patients with ALK-positive non–small-cell lung cancer from the registrational phase II study of lorlatinib. They analyzed baseline plasma and tumor tissue samples and assessed objective response rate, duration of response, and progression-free survival by ALK mutation status. According to the findings, a greater efficacy was displayed by lorlatinib in patients with ALK mutations vs patients without ALK mutations among those who had failed 1 or more second-generation ALK tyrosine kinase inhibitors (TKIs). Patients with more chances to derive clinical benefit from lorlatinib could be detected via tumor genotyping for ALK mutations following the failure of a second-generation TKI.