MO01.03 Biomarker Testing Patterns and Treatment Outcomes in Patients With Advanced Non-Small Cell Lung Cancer and MET Exon 14 Skipping Mutations

Abstract

MET exon 14 skipping mutation (METex14) occurs in ∼3% of patients with non-small cell lung cancer (NSCLC) and is a poor prognostic factor. Prior to capmatinib, the first FDA-approved therapy targeting METex14, chemotherapy and immuno-oncology (IO) therapy were commonly used to treat patients with METex14 NSCLC. Because treatment decisions also depend upon biomarker testing results, this study examines biomarker testing patterns and clinical outcomes of chemotherapy and IO in patients with advanced NSCLC (aNSCLC) and METex14. A descriptive retrospective study was conducted using the Flatiron Health–Foundation Medicine Clinico-Genomic Database (CGDB). Adult aNSCLC patients with METex14 confirmed by next-generation sequencing (NGS) testing who received ≥1 line of systemic therapy were included in the biomarker testing pattern analysis. The duration from specimen collection (as testing order date was unavailable) to reported results was assessed for METex14 and PD-L1 tested patients. Duration was only reported for specimens collected in 2019, the most recent year for which data were available, to minimize potential overestimation due to tissue archiving. Clinical outcomes were assessed in patients initiating IO monotherapy or chemotherapy as first-line (1L) and second-line (2L) therapy. Real-world progression-free survival (RW-PFS) was estimated using Kaplan-Meier analysis. Among 91 patients eligible for inclusion in the biomarker testing pattern analysis and confirmed positive for METex14 by NGS testing, 62% received PD-L1 testing, and 60% and 77% received NGS and PD-L1 testing within 3 months post aNSCLC diagnosis, respectively. Among 9 patients who were assessed for both METex14 and PD-L1 with specimen collection dates in 2019, the median duration between specimen collection and reporting for NGS was 7 days longer than that for PD-L1. Median RW-PFS was 5.7 months [95% CI, 4.6-7.1] and 2.4 months [95% CI, 1.4-3.2] in patients on 1L chemotherapy (n=59) and 1L IO monotherapy (n=18), with 3month RW-PFS rates of 78% and 33%, respectively. Median RW-PFS was 3.5 months [95% CI, 1.9-11.1] and 4.7 months [95% CI, 2.8-12.9] in patients on 2L chemotherapy (n=16) and 2L IO monotherapy (n=23), with 3-month RW-PFS rates of 54% and 67%, respectively. Among patients with METex14 aNSCLC in the real-world setting, IO monotherapy was associated with limited RW-PFS, and similar results were observed with chemotherapy. In this study, the difference in median duration between specimen collection and reporting of NGS and PD-L1 results was 7 days. Future real-world studies are needed to assess the effectiveness of different regimens in the METex14 population.