Prolonged survival and response to tepotinib in a non-small-cell lung cancer patient with brain metastases harboring MET exon 14 mutation: a research report.

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.

Roth KG ，Mambetsariev I ，Salgia R 《-》

Dramatic intracranial response to tepotinib in a patient with lung adenocarcinoma harboring MET exon 14 skipping mutation.

Mesenchymal-epithelial transition (MET) pathway activation is associated with the mechanisms that influence properties affecting cancer cell survival and invasiveness. The MET exon 14 skipping mutation (METex14del) is found in 2%-3% of patients with non-small cell lung cancer (NSCLC). Previous studies reported that NSCLC patients harboring a METex14del responded well to MET-tyrosine kinase inhibitors (TKIs), including tepotinib. Tepotinib is a highly selective, once-daily oral MET inhibitor that has shown promising clinical activity in patients with NSCLC with METex14del. The Food and Drug Administration accepted a new drug application for tepotinib as a treatment for patients with metastatic NSCLC harboring METex14del in February 2021 [Correction added on 5 March 2021, after first online publication: the FDA approval date for tepotinib has been corrected from 'September 2019' to 'February 2021'.]. However, in the previous clinical trials involving MET-TKIs, only patients with stable central nervous system metastases were eligible, and those with untreated symptomatic brain metastases (BMs) were excluded. Therefore, the efficacy and safety of MET-TKIs in that population remains unknown. We herein report a case of dramatic intracranial response to tepotinib in a patient with symptomatic BMs from lung adenocarcinoma harboring METex14del. In the current report, the symptoms derived from multiple BMs (headache and loss of appetite) rapidly disappeared, and brain magnetic resonance imaging (MRI) examination showed that all the lesions were too small to measure only 23 days after the commencement of tepotinib. For NSCLC patients with multiple BMs, whole-brain irradiation is a standard-of-care therapy, but its adverse effects on neurocognition are concerning. Tepotinib might therefore be a therapeutic option for NSCLC patients with symptomatic multiple BMs harboring METex14del.

Takamori S ，Matsubara T ，Fujishita T ，Ito K ，Toyozawa R ，Seto T ，Yamaguchi M ，Okamoto T ... -  《-》

Therapeutic strategies in METex14 skipping mutated non-small cell lung cancer.

METex14 skipping mutations occur in about 3-4% of lung adenocarcinoma patients and 1-2% of patients with other lung cancer histology. The MET receptor tyrosine kinase and its ligand hepatocyte growth factor (HGF) are established oncogenic drivers of NSCLC. A mutation that results in loss of exon 14 in the MET gene leads to dysregulation and inappropriate signaling that is associated with increased responsiveness to MET TKIs. Results from GEOMETRY mono-1 and VISION Phase I/II clinical trials demonstrated significant clinical activity in patients treated with the MET Exon 14 skipping mutation inhibitors capmatinib and tepotinib with tolerable toxicity profile. In the GEOMETRY mono-1 trial, capmatinib was especially active in treatment-naïve patients supporting the upfront testing of this oncogenic driver. Tepotinib demonstrated superior activity in the pretreated patients in the VISION trial. Savolitinib is another MET TKI that has shown efficacy in the first- and second-line settings, including patients with aggressive pulmonary sarcomatoid carcinoma. These studies have demonstrated that these TKIs can cross the blood brain barrier and demonstrated some activity toward CNS metastases. MET Exon 14 skipping mutation is detected by NGS-based testing of liquid or tissue biopsies, with preference for RNA-based NGS. The activity of capmatinib and tepotinib is limited by the development of acquired resistance. Current research is focused on strategies to overcome resistance and improve the effectiveness of these agents. Our aim is to review the current status of MET Exon 14 skipping mutation as it pertains NSCLC.

Drusbosky LM ，Dawar R ，Rodriguez E ，Ikpeazu CV ... -  《Journal of Hematology & Oncology》

Foretinib can overcome common on-target resistance mutations after capmatinib/tepotinib treatment in NSCLCs with MET exon 14 skipping mutation.

Capmatinib and tepotinib are guideline-recommended front-line treatments for non-small-cell lung cancer (NSCLC) patients with MET exon 14 skipping mutations (METex14). However, the emergence of acquired resistance to capmatinib/tepotinib is almost inevitable partially due to D1228X or Y1230X secondary mutations of the MET. In this study, we explored agents that are active against both D1228X and Y1230X MET to propose an ideal sequential treatment after capmatinib/tepotinib treatment failure in NSCLC patients with METex14. The inhibitory effects of 300 drugs, including 33 MET-TKIs, were screened in Ba/F3 cells carrying METex14 plus MET D1228A/Y secondary mutations. The screen revealed four-candidate type II MET-TKIs (altiratinib, CEP-40783, foretinib and sitravatinib). Therefore, we performed further growth inhibitory assays using these four MET-TKIs plus cabozantinib and merestinib in Ba/F3 cells carrying MET D1228A/E/G/H/N/V/Y or Y1230C/D/H/N/S secondary mutations. We also performed analyses using Hs746t cell models carrying METex14 (with mutant allele amplification) with/without D1228X or Y1230X in vitro and in vivo to confirm the findings. Furthermore, molecular dynamics (MD) simulations were carried out to examine differences in binding between type II MET-TKIs. All 6 type II MET-TKIs were active against Y1230X secondary mutations. However, among these 6 agents, only foretinib showed potent activity against D1228X secondary mutations of the MET in the Ba/F3 cell and Hs746t in vitro model and Hs746t in vivo model, and CEP-40783 and altiratinib demonstrated some activity. MD analysis suggested that the long tail of foretinib plays an important role in binding D1228X MET through interaction with a residue at the solvent front (G1163). Tertiary G1163X mutations, together with L1195F/I and F1200I/L, occurred as acquired resistance mechanisms to the second-line treatment foretinib in Ba/F3 cell models. The type II MET-TKI foretinib may be an appropriate second-line treatment for NSCLCs carrying METex14 after campatinib/tepotinib treatment failure by secondary mutations at residue D1228 or Y1230.

Fujino T ，Suda K ，Koga T ，Hamada A ，Ohara S ，Chiba M ，Shimoji M ，Takemoto T ，Soh J ，Mitsudomi T ... -  《Journal of Hematology & Oncology》

Tepotinib in Non-Small-Cell Lung Cancer with MET Exon 14 Skipping Mutations.

A splice-site mutation that results in a loss of transcription of exon 14 in the oncogenic driver MET occurs in 3 to 4% of patients with non-small-cell lung cancer (NSCLC). We evaluated the efficacy and safety of tepotinib, a highly selective MET inhibitor, in this patient population. In this open-label, phase 2 study, we administered tepotinib (at a dose of 500 mg) once daily in patients with advanced or metastatic NSCLC with a confirmed MET exon 14 skipping mutation. The primary end point was the objective response by independent review among patients who had undergone at least 9 months of follow-up. The response was also analyzed according to whether the presence of a MET exon 14 skipping mutation was detected on liquid biopsy or tissue biopsy. As of January 1, 2020, a total of 152 patients had received tepotinib, and 99 patients had been followed for at least 9 months. The response rate by independent review was 46% (95% confidence interval [CI], 36 to 57), with a median duration of response of 11.1 months (95% CI, 7.2 to could not be estimated) in the combined-biopsy group. The response rate was 48% (95% CI, 36 to 61) among 66 patients in the liquid-biopsy group and 50% (95% CI, 37 to 63) among 60 patients in the tissue-biopsy group; 27 patients had positive results according to both methods. The investigator-assessed response rate was 56% (95% CI, 45 to 66) and was similar regardless of the previous therapy received for advanced or metastatic disease. Adverse events of grade 3 or higher that were considered by investigators to be related to tepotinib therapy were reported in 28% of the patients, including peripheral edema in 7%. Adverse events led to permanent discontinuation of tepotinib in 11% of the patients. A molecular response, as measured in circulating free DNA, was observed in 67% of the patients with matched liquid-biopsy samples at baseline and during treatment. Among patients with advanced NSCLC with a confirmed MET exon 14 skipping mutation, the use of tepotinib was associated with a partial response in approximately half the patients. Peripheral edema was the main toxic effect of grade 3 or higher. (Funded by Merck [Darmstadt, Germany]; VISION ClinicalTrials.gov number, NCT02864992.).

Paik PK ，Felip E ，Veillon R ，Sakai H ，Cortot AB ，Garassino MC ，Mazieres J ，Viteri S ，Senellart H ，Van Meerbeeck J ，Raskin J ，Reinmuth N ，Conte P ，Kowalski D ，Cho BC ，Patel JD ，Horn L ，Griesinger F ，Han JY ，Kim YC ，Chang GC ，Tsai CL ，Yang JC ，Chen YM ，Smit EF ，van der Wekken AJ ，Kato T ，Juraeva D ，Stroh C ，Bruns R ，Straub J ，Johne A ，Scheele J ，Heymach JV ，Le X ... -  《-》