Efficacy and Tolerability of ALK/MET Combinations in Patients With ALK-Rearranged Lung Cancer With Acquired MET Amplification: A Retrospective Analysis

Introduction: MET amplification is a potentially actionable resistance mechanism in ALK-rearranged (ALK+) lung cancer. Studies describing treatment outcomes of this mo-lecular subgroup are lacking.Methods: We assembled a cohort of patients with ALK+ lung cancer and acquired MET amplification (identified by tissue or plasma) who received regimens targeting both ALK and MET. Efficacy and safety were assessed using the Response Evaluation Criteria in Solid Tumors version 1.1 and Common Terminology Criteria for Adverse Events version 4.03, respectively.Results: A total of 12 patients were included in the series. MET amplification was detected after a median of 1.5 (range 1-5) lines of therapy. Four distinct regimens were imple-mented to address MET amplification: crizotinib (n = 2), lorlatinib plus crizotinib (n = 6), alectinib plus capmatinib (n = 3), and alectinib plus crizotinib (n = 1). Partial re-sponses were observed in five (42%) of 12 patients, including patients who received crizotinib (n = one of two), lorlatinib plus crizotinib (n = three of six), and alectinib plus capmatinib (n = one of three). Primary progression was observed in four patients (33%). Grades 1 to 2 pe-ripheral edema, occurring in seven (58%) patients, was found with both crizotinib and capmatinib. One patient required dose reduction of capmatinib plus alectinib for persistent grade 2 edema. Across the regimens, one patient discontinued therapy for toxicity, specifically neurocognitive toxicity from lorlatinib plus crizotinib. At progression on ALK+ MET therapy, potential resistance mechanisms included MET copy number changes and ALK kinase domain mutations.Conclusions: Combined ALK and MET inhibition is associated with moderate antitumor activity in patients with ALK+ NSCLC with concurrent MET amplification. Prospective studies are indicated to confirm activity and identify individuals most likely to benefit from the treatment.(c) 2023 The Authors. Published by Elsevier Inc. on behalf of the International Association for the Study of Lung Cancer. This is an open access article under the CC BY-NC-ND li-cense (http://creativecommons.org/licenses/by-nc-nd/ 4.0/).