MET exon 14 skipping mutations in non-small-cell lung cancer: real-world data from the Italian biomarker ATLAS database

Background: Mesenchymal–epithelial transition (MET) exon 14 (METex14) skipping mutation is a rare alteration in non-small-cell lung cancer (NSCLC), occurring in about 3%-4% of cases. Here we report disease and patient characteristics, and efficacy and tolerability of MET inhibitors among advanced METex14 NSCLC patients from the Italian real-world registry ATLAS. Materials and methods: Clinical-pathological and molecular data, and treatment efficacy/tolerability outcomes were retrospectively collected from the ATLAS registry. Results: From July 2020 to July 2023 a total of 146 METex14 advanced NSCLC patients were included across 27 Italian centers. Median age was 74 years, and most patients were male (52%), with an Eastern Cooperative Oncology Group performance status < 2 (72%) and adenocarcinoma subtype (83%). One hundred and twenty-five out of 146 (86%) patients received at least one line of systemic anticancer therapy. Fifty-six (38%) were treated with capmatinib and 34 (23%) with tepotinib. 29% and 52% of them received targeted treatment in the first and second line, respectively. In the cohort of patients treated with MET inhibitors, the response rate (RR) was 37% (33% in previously treated patients and 46% in treatment-naïve) with a disease control rate of 62%. With a median follow-up of 10.8 months, progression-free survival was 6.6 months [95% confidence interval (CI) 4.3-8.3 months] and overall survival was 10.7 months (95% CI 7.2-19.3 months). In patients with measurable brain metastases (17 cases), the intracranial RR was 41%. Grade ≥3 treatment-related adverse events (TRAEs) occurred in 12% of patients with grade 3 peripheral edema in 7% of cases. A fatal adverse reaction occurred in one patient due to pneumonitis. TRAEs-related dose reduction and discontinuation were reported in 6% and 8% of cases, respectively. Conclusion: Capmatinib and tepotinib represent an effective treatment option in NSCLC patients with METex14. Real-world efficacy outcomes are worse than those reported in prospective clinical trials. Their activity is more pronounced in the treatment-naïve population, suggesting that this is the right setting in the management of patients with METex14.