Tyrosine kinase inhibitors (TKIs) have transformed the standard of care in lung 
cancer. A number of TKIs have been discovered that specifically target 
oncogenes, including MET receptor tyrosine kinase. Second-generation MET TKIs 
are showing improved efficacy over first-generation TKIs. Herein, we report a 
case of a patient with metastatic lung adenocarcinoma harboring a MET exon 14 
splice site mutation who has had prolonged disease control by a 
second-generation MET-TKI tepotinib. A 66-yr-old man was diagnosed with stage IV 
lung adenocarcinoma. He was started on carboplatin, paclitaxel, and bevacizumab, 
but had severe toxicity. He was switched to pembrolizumab as his tumor was PD-L1 
70%, and molecular testing was not yet performed because of insufficient tissue. 
A bronchoscopy with endobronchial ultrasound was performed and a MET exon 14 
splice site mutation was detected by next-generation sequencing. Upon 
progression, he was then enrolled in a clinical trial of tepotinib and continues 
with stable disease for more than 45 cycles and 31 mo. The MET receptor tyrosine 
kinase and the ligand hepatocyte growth factor (HGF) have been implicated as 
oncogenes and drivers of non-small-cell lung cancer (NSCLC). Newer MET TKIs 
including capmatinib and tepotinib more recently showed not only improved 
localized control and response, but early data suggests intracranial activity as 
compared to first-generation MET TKIs, both in the front-line and the refractory 
setting. This is a case report demonstrating an effective duration of response 
in a patient with widely metastatic lung adenocarcinoma harboring a MET exon 14 
mutation.