Intracranial Response to Capmatinib After Progression on Crizotinib in a Patient with Exon 14 Skipping Non-small Cell Lung Cancer-a Case Report

Background: Capmatinib, a potent and selective tyrosine kinase inhibitor (TKI), holds promise as a therapeutic agent due to its potentially elevated intracranial efficacy in metastatic non-small cell lung cancer (NSCLC) patients harboring exon 14 skipping alterations in (MET Proto-Oncogene). This study aims to evaluate a targeted therapeutic approach to an exon 14 skipping (METex14) advanced NSCLC patient that progressed on Crizotinib and developed off target resistance alteration in PIK3CA.

Case Discription: We present a case of advanced METex14 NSCLC patient wherein central nervous system (CNS) relapse occurred post complete surgical resection and remission of the lung tumor under first-line crizotinib treatment. Subsequent disease monitoring demonstrated a profound intracranial response to capmatinib in a crizotinib-resistant brain lesion. Molecular analysis unveiled the original METex14 D1028N driver mutation and a newly arisen bypass mutation, potentially contributing to off-target resistance.

Conclusions: Before capmatinib was approved as a first line treatment option for metastatic NSCLC harboring somatic METex14 mutations, crizotinib conferred a potential option for targeted treatment. Switching to a selective -TKI like capmatinib with a better CNS penetration, it appears to be a promising approach for CNS metastasized NSCLC patients with METex14 mutations that failed on crizotinib. Further research is needed to more effectively understand and monitor resistance mechanisms using advanced diagnostic techniques such as DNA-based hybrid-capture (HC) next generation sequencing (NGS) to guide molecularly stratified therapy beyond the first line setting.