Case report: Response to tepotinib in Chinese non-small cell lung cancer patients harboring METex14 skipping with varying features.

MET exon 14 (METex14) skipping is the most reported MET mutation in non-small cell lung cancer (NSCLC) and has been confirmed to respond to MET tyrosine kinase inhibitors (TKI) in clinical trials. While MET TKI tepotinib was recently approved for METex14 skipping NSCLC in China, real-world evidence is limited. We report our experience treating NSCLC patients referred from oncology sites across China with tepotinib in the Boao Lecheng Pilot Zone. Four patients have been prescribed the drug with a median age of 67 years (range, 61-71 years). One patient has concomitant BRAF V600E mutation, and another patient had savolitinib as first line of therapy but discontinued due to hepatotoxicity. Till the end of follow-up, four patients were all on tepotinib therapy, with a median duration of therapy of 19 months. One patient achieved partial response and three achieved stable disease. Three patients had peripheral edema, but all were mild. Our experience showed in real clinical setting, tepotinib had robust and durable clinical activity and a favorable toxicity profile in Chinese patients with METex14 skipping NSCLC. It is the first report on the effectiveness of tepotinib in a patient with both METex14 skipping and BRAF V600E mutations and successful MET inhibitor switch after MET inhibitor-induced liver injury.

Mesenchymal-epithelial transition factor exon 14 skipping mutation-positive granulocyte colony-stimulating factor-producing lung adenocarcinoma mimicking lung abscess: A case report.

Granulocyte colony-stimulating factor (G-CSF)-producing lung tumours are rare, with their imaging features and effective treatments remaining elusive. Similarly, mesenchymal-epithelial transition (MET) exon 14 skipping mutations are also uncommon. Herein, we report a case of G-CSF-producing lung adenocarcinoma positive for a MET exon 14 skipping mutation, mimicking lung abscess. A 61-year-old man presented with cough and high fever. Contrast-enhanced chest computed tomography revealed a mass with a cavity and internal fluid accumulation. The patient initially underwent diagnostic treatment for a lung abscess but was ultimately diagnosed with lung adenocarcinoma positive for a MET exon 14 skipping mutation. Following tepotinib therapy, the primary lesion shrank, and serum G-CSF levels decreased, leading to a diagnosis of G-CSF-producing lung cancer. G-CSF-producing lung tumours can present imaging findings that mimic lung abscesses. Tepotinib therapy may be effective for patients with MET exon 14 skipping mutation, including those with G-CSF-producing lung cancer.

Brief Report: Tepotinib as a Treatment Option in MET Exon 14 Skipping-Positive Lung Cancers-Investigating Discordance Between ArcherMET and the Oncomine Dx Target Test.

Introduction: NSCLC is a leading cause of cancer-related mortality worldwide. Specific genetic alterations, such as MET exon 14 (METex14) skipping, have been identified in NSCLC, allowing targeted therapy. Tepotinib, a highly selective MET inhibitor, has displayed promise in patients with advanced NSCLC. Nevertheless, challenges arise when identifying treatment strategies for patients with discordant results regarding METex14 skipping detection between diagnostic tests. Methods: We investigated patients with NSCLC and discordant results for METex14 skipping between the Oncomine Dx Target Test (ODxTT) and ArcherMET. Clinical response, adverse events, and the duration of tepotinib treatment were assessed, and statistical analysis was performed. Results: Among the 19 patients deemed METex14 skipping positive by ODxTT, only 10 had concordant results with ArcherMET. The number of METex14 skipping reads detected by ODxTT was significantly lower in discordant cases. Of the 19 patients, 14 received tepotinib, and comparable response and disease control rates were observed in both concordant and discordant cases. The duration of treatment did not significantly differ between the two groups. Conclusions: Our findings suggest that tepotinib has comparable therapeutic effects in patients with METex14 skipping-positive NSCLC irrespective of the concordance of results between ODxTT and ArcherMET. Tepotinib is a possible treatment option for patients with METex14 skipping, even in patients with discordant test results.

A novel HLA-DQB2::MET gene fusion variant in lung adenocarcinoma with prolonged response to tepotinib: a case report.

Background: MET rearrangements are infrequently observed in non-small cell lung cancer (NSCLC). Advanced genomic detection techniques have unveiled such infrequent genomic variations, particularly MET fusions in approximately 0.5% of NSCLC patients. Tyrosine kinase inhibitors (TKIs) have revolutionized the standard of care in lung cancer and more recently a second generation MET TKI tepotinib received Food and Drug Administration (FDA) approval for MET exon 14 alterations in metastatic NSCLC. Despite this, the therapeutic landscape for MET-rearranged NSCLC patients remains significantly unexplored. The aim of our report is to detail a unique case of a patient with metastatic lung adenocarcinoma with a novel HLA-DQB2::MET fusion detected by next-generation sequencing (NGS) following previous treatment resistance. Case Description: A 73-year-old female was initially started on carboplatin, pemetrexed and pembrolizumab with maintenance, but eventually had progression in the left upper lobe (LUL). Upon progression she was enrolled in a clinical trial of a monoclonal antibody with or without a PD-1 inhibitor, but brain metastasis progression was eventually detected by magnetic resonance imaging (MRI) requiring stereotactic radiosurgery (SRS) and a craniotomy. The trial drug was eventually discontinued due to progression and toxicity and NGS on bronchoscopy tissue revealed HLA-DQB2::MET fusion. The patient was initiated on tepotinib and continues with clinical and radiological stable disease for over 12 months. The patient's response to a MET inhibitor, tepotinib, underscores the potential efficacy of selective MET inhibitors for individuals with previously unexplored MET fusions. Conclusions: The positive response to tepotinib of a patient with NSCLC harboring a novel MET-Fusion underscores the importance of the use of comprehensive next-generational sequencing-based panels and highlights the necessity for additional research and clinical exploration of selective MET inhibitors for managing NSCLC with MET rearrangements.

Prolonged complete response to adjuvant tepotinib in a patient with newly diagnosed disseminated glioblastoma harboring mesenchymal-epithelial transition fusion.

The prognosis of patients with glioblastoma (GBM) remains poor despite current treatments. Targeted therapy in GBM has been the subject of intense investigation but has not been successful in clinical trials. The reasons for the failure of targeted therapy in GBM are multifold and include a lack of patient selection in trials, the failure to identify driver mutations, and poor blood-brain barrier penetration of investigational drugs. Here, we describe a case of a durable complete response in a newly diagnosed patient with GBM with leptomeningeal dissemination and PTPRZ1-MET fusion who was treated with tepotinib, a brain-penetrant MET inhibitor. This case of successful targeted therapy in a patient with GBM demonstrates that early molecular testing, identification of driver molecular alterations, and treatment with brain-penetrant small molecule inhibitors have the potential to change the outcome in select patients with GBM.

Effective treatment of MET exon 14 skipping mutation-positive non-small cell lung cancer using capmatinib following serious maculopapular rash caused by two MET inhibitors: a case report.

Background: Multi-gene panel testing and advancements in molecular targeted therapy have improved the overall survival of patients with driver mutation-positive non-small cell lung cancer (NSCLC). Mesenchymal-epithelial transition factor (MET) exon 14 skipping mutation-positive NSCLC, which remains untreated with MET inhibitors, shows a poorer prognosis than do cases of NSCLC without MET mutations. However, serious treatment-related adverse events (TRAEs) act as substantial treatment barriers. Case Description: Herein, we report a case of advanced NSCLC in a male in his 40s with MET exon 14 skipping mutation. A MET-inhibitory investigational drug was administered as first-line treatment; the development of grade 3 maculopapular rash necessitated dose reduction, which resulted in disease progression. Tepotinib was then administered with dexamethasone as a third-line treatment but was discontinued owing to the re-development of the grade 3 maculopapular rash. Finally, capmatinib administration as the fifth-line treatment appeared partially effective, with no serious adverse events. The patient could successfully resume work. Conclusions: This is the first report of MET exon 14 skipping mutation-positive NSCLC wherein partial response was achieved without severe TRAEs by alternating between two MET inhibitors. If no alternative treatments are available, cautious repeated re-administration of MET inhibitors after resolving serious rashes can be considered a potential approach.

Tepotinib-induced hand-foot skin reaction.

Tepotinib may cause hand-foot skin reactions with keratotic changes. When such changes are observed in the hands or toes after starting tepotinib treatment, its side effects should be considered, and corticosteroid ointment or withdrawal of tepotinib should be considered if necessary.

Absence of cross-toxicity between MET inhibitors in a non-small-cell lung cancer with a MET exon 14 skipping mutation.

INTRODUCTION: Selective tyrosine kinase inhibitors are proven effective in patients with non-small lung cancer (NSCLC) with a MET exon 14 skipping mutation. CASE PRESENTATION: The patient developed a metastatic lung adenocarcinoma with a MET exon 14 skipping mutation. She was treated with a first 1b MET inhibitor, Capmatinib, but had to stop the drug because of major hepatotoxicity. A few months later, she started Tepotinib, another 1b MET inhibitor with this time, no sign of hepatotoxicity. DISCUSSION: Adverse events are frequent with 1b MET inhibitors. However, there is a wide interpatient variability. Absence of cross-toxicity between Capmatinib and Tepotinib is misunderstood but can be explained by slight differences in phamarcodynamics and pharmacokinetics. Practitionners have to be warned about severe adverse events to stop or change the drug if necessary. CONCLUSION: This is the first case showing the absence of cross-toxicity between 1b MET inhibitors.

Long-term experience with tepotinib in Japanese patients with MET exon 14 skipping NSCLC from the Phase II VISION study.

Tepotinib is a highly selective MET tyrosine kinase inhibitor (TKI) that has demonstrated robust and durable clinical activity in patients with MET exon 14 (METex14) skipping non-small-cell lung cancer (NSCLC). In the Phase II VISION study, patients received oral tepotinib 500 mg once daily. The primary endpoint was an objective response by an independent review committee (IRC) according to RECIST v1.1 criteria. The secondary endpoints included duration of response (DOR), progression-free survival (PFS), overall survival (OS), and safety. Here we report the analysis of the efficacy and safety of tepotinib in all Japanese patients with advanced METex14 skipping NSCLC from VISION (n = 38) with >18 months' follow-up. The median age of the Japanese patients was 73 years (range 63-88), 39.5% of patients were ≥75 years old, 68.4% were male, 55.3% had a history of smoking, 76.3% had adenocarcinoma, and 10.5% of patients had known brain metastases at baseline. Overall, the objective response rate (ORR) was 60.5% (95% confidence interval (CI): 43.4, 76.0) with a median DOR of 18.5 months (95% CI: 8.3, not estimable). ORR in treatment-naïve patients (n = 18) was 77.8% (95% CI: 52.4, 93.6), and in patients aged ≥75 years (n = 15), ORR was 73.3% (95% CI: 44.9, 92.2). The most common treatment-related adverse event (AE) with any grade was blood creatinine increase (65.8%), which resolved following tepotinib discontinuation. Other common treatment-related AEs were peripheral edema (60.5%), hypoalbuminemia (34.2%), diarrhea (28.9%), and nausea (15.8%). In summary, tepotinib demonstrated robust and durable clinical activity irrespective of age or therapy line, with a manageable safety profile in Japanese patients with METex14 skipping NSCLC enrolled in VISION.

Comparison of Tepotinib, Paclitaxel, or Ramucirumab Efficacy According to the Copy Number or Phosphorylation Status of the MET Gene: Doublet Treatment versus Single Agent Treatment.

Although conventional combination chemotherapies for advanced gastric cancer (GC) increase survival, such therapies are associated with major adverse effects; more effective and less toxic treatments are required. Combinations of different anti-cancer drugs, for example, paclitaxel plus ramucirumab, have recently been used as second-line treatments for advanced GC. This study evaluated how copy number variations of the MET gene, MET mutations, and MET gene and protein expression levels in human GC cells modulate the susceptibility of such cells to single-agent (tepotinib, ramucirumab, or paclitaxel) and doublet (tepotinib-plus-paclitaxel or ramucirumab-plus-paclitaxel treatment regimens. Compared with ramucirumab-plus-paclitaxel, tepotinib-plus-paclitaxel better inhibited the growth of GC cells with MET exon 14 skipping mutations and those lacking MET amplification but containing phosphorylated MET; such inhibition was dose-dependent and associated with cell death. Tepotinib-plus-paclitaxel and ramucirumab-plus-paclitaxel similarly inhibited the growth of GC cells lacking MET amplification or MET phosphorylation, again in a dose-dependent manner, but without induction of cell death. However, tepotinib alone or tepotinib-plus-ramucirumab was more effective against c-MET-positive GC cells (>30 copy number variations) than was ramucirumab or paclitaxel alone or ramucirumab-plus-paclitaxel. These in vitro findings suggest that compared with ramucirumab-plus-paclitaxel, tepotinib-plus-paclitaxel better inhibits the growth of c-MET-positive GC cells, cells lacking MET amplification but containing phosphorylated MET, and cells containing MET mutations. Clinical studies are required to confirm the therapeutic effects of these regimens.

Mesenchymal-epithelial transition Exon 14-Skipping Mutation-positive Invasive Mucinous Adenocarcinoma of the Lung: First Case Treated with Mesenchymal-epithelial Transition-tyrosine Kinase Inhibitors.

Mesenchymal-epithelial transition (MET) exon 14-skipping mutation (METex14) is rare in pulmonary invasive mucinous adenocarcinomas (IMAs), and the clinical impact of MET-tyrosine kinase inhibitors (TKIs) remains unknown. We herein report a 75-year-old woman with IMA harboring METex14 who was treated with the MET-TKI tepotinib. The lung tumor regressed over six months; however, the patient ultimately died of exacerbated interstitial lung disease (ILD), possibly associated with tepotinib. An autopsy revealed diffuse alveolar damage in preexisting chronic fibrosis. We discuss how to pre-evaluate ILD deterioration risks and monitor TKI-induced lung toxicity during treatment.

Tepotinib in patients with non-small cell lung cancer with high-level MET amplification detected by liquid biopsy: VISION Cohort B.

High-level MET amplification (METamp) is a primary driver in ∼1%-2% of non-small cell lung cancers (NSCLCs). Cohort B of the phase 2 VISION trial evaluates tepotinib, an oral MET inhibitor, in patients with advanced NSCLC with high-level METamp who were enrolled by liquid biopsy. While the study was halted before the enrollment of the planned 60 patients, the results of 24 enrolled patients are presented here. The objective response rate (ORR) is 41.7% (95% confidence interval [CI], 22.1-63.4), and the median duration of response is 14.3 months (95% CI, 2.8-not estimable). In exploratory biomarker analyses, focal METamp, RB1 wild-type, MYC diploidy, low circulating tumor DNA (ctDNA) burden at baseline, and early molecular response are associated with better outcomes. Adverse events include edema (composite term; any grade: 58.3%; grade 3: 12.5%) and constipation (any grade: 41.7%; grade 3: 4.2%). Tepotinib provides antitumor activity in high-level METamp NSCLC (ClinicalTrials.gov: NCT02864992).

First-line tepotinib for a very elderly patient with metastatic NSCLC harboring MET exon 14 skipping mutation and high PD-L1 expression.

Optimal treatment for metastatic non-small cell lung cancer (NSCLC) with mesenchymal epithelial transition gene (MET) exon 14 skipping mutation has not been established yet. MET inhibitors were demonstrated to be effective and tolerated in patients with this condition, while evidence on safety and efficacy of immunotherapy and/or chemotherapy in this population is limited. Here we report the case of an 86-year-old male with metastatic NSCLC harboring MET exon 14 skipping mutation and with high programmed cell death ligand 1 (PD-L1) expression (tumor proportion score ≥50%). The patient received the MET inhibitor tepotinib as first-line treatment, achieving a partial response, with G2 peripheral edema as adverse event that was successfully managed with temporary discontinuation, dose reduction, diuretics and physical therapy. After 31 months, the patient is still receiving tepotinib, with an ongoing response. Tepotinib is a valuable therapeutic option for first-line treatment of older patients with NSCLC harboring MET exon 14 skipping mutation, even in the presence of high PD-L1 expression.

Biophysical and structural characterization of the impacts of MET phosphorylation on tepotinib binding.

The receptor tyrosine kinase MET is activated by hepatocyte growth factor binding, followed by phosphorylation of the intracellular kinase domain (KD) mainly within the activation loop (A-loop) on Y1234 and Y1235. Dysregulation of MET can lead to both tumor growth and metastatic progression of cancer cells. Tepotinib is a highly selective, potent type Ib MET inhibitor and approved for treatment of non-small cell lung cancer harboring METex14 skipping alterations. Tepotinib binds to the ATP site of unphosphorylated MET with critical π-stacking contacts to Y1230 of the A-loop, resulting in a high residence time. In our study, we combined protein crystallography, biophysical methods (surface plasmon resonance, differential scanning fluorimetry), and mass spectrometry to clarify the impacts of A-loop conformation on tepotinib binding using different recombinant MET KD protein variants. We solved the first crystal structures of MET mutants Y1235D, Y1234E/1235E, and F1200I in complex with tepotinib. Our biophysical and structural data indicated a linkage between reduced residence times for tepotinib and modulation of A-loop conformation either by mutation (Y1235D), by affecting the overall Y1234/Y1235 phosphorylation status (L1195V and F1200I) or by disturbing critical π-stacking interactions with tepotinib (Y1230C). We corroborated these data with target engagement studies by fluorescence cross-correlation spectroscopy using KD constructs in cell lysates or full-length receptors from solubilized cellular membranes as WT or activated mutants (Y1235D and Y1234E/1235E). Collectively, our results provide further insight into the MET A-loop structural determinants that affect the binding of the selective inhibitor tepotinib.

A case of successful desensitization treatment with tepotinib after tepotinib-induced rash.

Tepotinib is one of the key drugs for MET exon 14-skipping mutation-positive non-small cell lung cancer (NSCLC). The main adverse event of tepotinib treatment is edema. Rash is a rare adverse event, affecting only 0.7% of patients. We report a case of successful desensitization after skin rash caused by tepotinib. A 61-year-old male was treated with tepotinib 500 mg as second-line therapy for NSCLC with MET exon 14-skipping mutation. Treatment was discontinued on day 12 due to grade 3 erythema throughout the body. After improvement of the skin rash, he was started on 250 mg tepotinib with an oral antihistamine and topical steroid. Treatment was discontinued on day 11 due to skin rash exacerbation. One month of treatment-free follow-up showed skin rash improvement but lung carcinoma growth. Tepotinib desensitization therapy was started at a dose of 12.5 mg and gradually increased to 250 mg/day. The patient has since continued tepotinib treatment without skin rashes. Desensitization therapy may be effective for managing skin rash due to tepotinib.

The Treatment of a New Entity in Advanced Non-Small Cell Lung Cancer: MET exon 14 Skipping Mutation.

BACKGROUND: MET (MET Proto-Oncogene, Receptor Tyrosine Kinase) exon 14 skipping mutation represents one of the most common MET alterations, accounting for approximately 1-3% of all mutations in advanced lung adenocarcinomas. While until 2020 no specific treatment was available for this subset of patients, as of today, three MET Tyrosine Kinase Inhibitors (TKIs) are currently approved in this setting, namely capmatinib, tepotinib and savolitinib. OBJECTIVE: This article aims to provide an extensive overview of the current therapeutic standard of care for exon 14 skipped advanced Non-Small Cell Lung Cancer (NSCLC) patients, alongside with mentions of the main future challenges and opportunities. CONCLUSION: FDA-approved MET-TKIs currently represent the best option for treating exon 14 skipped advanced NSCLC patients, thanks to their excellent efficacy profile, alongside their manageable safety and tolerability. However, we currently lack specific agents to treat patients progressing on capmatinib or tepotinib, due to a limited understanding of the mechanisms underlying both on- and off-target resistance. In this respect, on-target mutations presently constitute the most explored ones from a mechanistic point of view, and type II MET-TKIs are currently under investigation as the most promising agents capable of overcoming the acquired resistance.

MET Exon 14 Skipping in NSCLC: A Systematic Literature Review of Epidemiology, Clinical Characteristics, and Outcomes.

INTRODUCTION: MET exon 14 (METex14) skipping is a rare oncogenic driver in non-small-cell lung cancer (NSCLC) for which targeted therapy with MET tyrosine kinase inhibitors (TKIs) was recently approved. Given the heterogeneity in published data of METex14 skipping NSCLC, we conducted a systematic literature review to evaluate its frequency, patient characteristics, and outcomes. METHODS: On June 13, 2022 we conducted a systematic literature review of publications and conference abstracts reporting frequency, patient characteristics, or outcomes of patients with METex14 skipping NSCLC. RESULTS: We included 139 studies reporting frequency or patient characteristics (350,997 patients), and 39 studies reporting clinical outcomes (3989 patients). Median METex14 skipping frequency was 2.0% in unselected patients with NSCLC, with minimal geographic variation. Median frequency was 2.4% in adenocarcinoma or nonsquamous subgroups, 12.0% in sarcomatoid, and 1.3% in squamous histology. Patients with METex14 skipping NSCLC were more likely to be elderly, have adenocarcinoma histology; there was no marked sex or smoking status distribution. In first line of treatment, median objective response rate ranged from 50.7% to 68.8% with targeted therapies (both values correspond to MET TKIs), was 33.3% with immunotherapy, and ranged from 23.1% to 27.0% with chemotherapy. CONCLUSIONS: Patients with METex14 skipping are more likely to have certain characteristics, but no patient subgroup can be ruled out; thus, it is crucial to test all patients with NSCLC to identify suitable candidates for MET inhibitor therapy. MET TKIs appeared to result in higher efficacy outcomes, although no direct comparison with chemotherapy or immunotherapy regimens was found.