Tepotinib Efficacy in a Patient with Non-Small Cell Lung Cancer with Brain Metastasis Harboring an HLA-DRB1-MET Gene Fusion

Dramatic response to crizotinib through MET phosphorylation inhibition in rare TFG-MET fusion advanced squamous cell lung cancer

With the widespread use of next-generation sequencing (NGS) for solid tumors, mesenchymal-to-epithelial transition factor (MET) rearrangement/fusion has been confirmed in multiple cancer types. MET amplification and MET exon 14 skipping mutations induce protein autophosphorylation; however, the pathogenic mechanism and drug sensitivity of MET fusion remain unclear. The following report describes the clinical case of a patient diagnosed with squamous lung cancer bearing a TFG-MET gene fusion. In vitro assays demonstrated MET phosphorylation and oncogenic capacity due to the TFG-MET rearrangement, both of which were inhibited by crizotinib treatment. The patient was treated with crizotinib, which resulted in sustained partial remission for more than 17 months. Collectively, cellular analyses and our case report emphasize the potential of MET fusion as a predictive biomarker for personalized target therapy for solid tumors.

Remarkable response to capmatinib in a patient with intrahepatic cholangiocarcinoma harboring TFG-MET fusion

Dysregulation of mesenchymal-epithelial transition factor (MET) gene due to amplification, mutation, and fusion has been reported in various types of human cancers. Recently, the efficacy of small-molecule tyrosine kinase inhibitors (TKIs) targeting MET has been demonstrated in a wide range of MET-dysregulated tumors. The majority of biliary tract cancers including intrahepatic cholangiocarcinoma (iCCA) are diagnosed at an advanced stage, and the utility of conventional chemotherapy is limited. Here, we present a case of metastatic iCCA harboring TFG-MET gene fusion, which demonstrated a remarkable response to treatment with capmatinib, a selective MET inhibitor. The patient was a 46-year-old man diagnosed with iCCA with hepatic, intraabdominal lymph nodes, and peritoneal metastases. Comprehensive genomic profiling (CGP) revealed TFG-MET gene fusion in his tumor. After becoming refractory to standard chemotherapy, he received capmatinib, which resulted in a marked shrinkage of the liver masses and lymph node metastases, as well as a drastic decrease in serum CA19-9 level. Our case reinforces the importance of CGP in exploring targeted therapy and supports the potential role of capmatinib in the treatment of tumors harboring MET fusions.

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.

Response to Savolitinib in a Patient with Advanced Poorly Differentiated Lung Carcinoma Positive for a Novel EML4-MET Gene Fusion

Background

Cellular-mesenchymal to epithelial transition factor (c-MET) alterations have significant therapeutic implications in non-small cell lung cancer (NSCLC). Although MET fusion is a rare genomic event, advances in detection technologies have enabled the identification of various MET fusion partner genes. However, standard therapeutic options for MET fusion in NSCLC cases remain undefined. This report presents a novel fusion variant, EML4-MET, encompassing exons 1 to 13 of EML4 and exons 15 to 21 of MET, including the entire MET kinase domain, and discusses the response of this case to savolitinib treatment.

Case Presentation

A 65-year-old woman was diagnosed with advanced poorly differentiated lung carcinoma. Molecular profiling of circulating tumor DNA (ctDNA), carried out by next-generation sequencing (NGS), identified a novel EML4-MET fusion. The patient was administered the MET receptor tyrosine kinase inhibitor savolitinib at 400 mg daily. One month later, computed tomography (CT) revealed some lesions with volume reduction. However, COVID-19 diminished the efficacy of savolitinib. Regrettably, the patient succumbed to respiratory and circulatory failure due to disease progression in March 2023.

Conclusion

This case uncovers a new type of MET fusion and expands the range of potential MET fusion targets in NSCLC. The patient responded to savolitinib, suggesting a reference basis for the treatment of similar cases with EML4-MET fusion in the future. Additional research is warranted to assess the biological significance of the EML4-MET fusion in NSCLC.

MET alterations detection platforms and clinical implications in solid tumors: a comprehensive review of literature

MET alterations, including MET exon 14 skipping variants, MET amplification, MET overexpression, and MET fusion, play pivotal roles in primary tumorigenesis and acquired resistance to targeted therapies, especially EGFR tyrosine kinase inhibitors. They represent important diagnostic, prognostic, and predictive biomarkers in many solid tumor types. However, the detection of MET alterations is challenging due to the complexity of MET alterations and the diversity of platform technologies. Therefore, techniques with high sensitivity, specificity, and reliable molecular detection accuracy are needed to overcome such hindrances and aid in biomarker-guided therapies. The current review emphasizes the role of MET alterations as oncogenic drivers in a variety of cancers and their involvement in the development of resistance to targeted therapies. Moreover, our review provides an overview of and recommendations on the selection of various cross-platform technologies for the detection of MET exon 14 skipping variants, MET amplification, MET overexpression, and MET fusion. Furthermore, challenges and hurdles underlying these common detection platforms are discussed.

MET fusions are targetable genomic variants in the treatment of advanced malignancies

Targeted therapy for malignancies has developed rapidly in recent years, benefiting patients harboring genetic mutations sensitive to relevant tyrosine kinase inhibitors (TKIs). With the development of targeted sequencing techniques, an increasing number of detectable genomic alterations in malignancies, including MET fusions, have been revealed. MET fusions, although rare among malignancies, might be functional driver genes that participate in activating downstream signaling pathways and promoting cell proliferation. Therefore, it is believed that MET fusions could be targetable genomic variants of MET, and inhibition of MET is considered an optionable therapeutic choice for patients harboring MET fusions. According to the summary presented in this review, we recommend MET-TKIs as suitable treatment agents for patients harboring primary MET fusions. For patients harboring acquired MET fusions after the development of resistance to TKIs targeting primary genomic alterations, such as sensitive EGFR mutations, treatment with a MET-TKI alone or in combination with TKIs targeting primary genomic alterations, such as EGFR-TKIs, is hypothesized to be a reasonable option for salvage treatment. In summary, MET fusions, despite their low incidence, should be taken into consideration when developing treatment strategies for cancer patients.

[Chinese Expert Consensus on the Clinical Practice of Non-small Cell Lung Cancer Fusion Gene Detection Based on RNA-based NGS]

RNA-based next-generation sequencing (NGS) has been recommended as a method for detecting fusion genes in non-small cell lung cancer (NSCLC) according to clinical practice guidelines and expert consensus. The primary targetable alterations in NSCLC consist of gene mutations and fusions, making the detection of gene mutations and fusions indispensable for assessing the feasibility of targeted therapies. Currently, the integration of DNA-based NGS and RNA-based NGS allows for simultaneous detection of gene mutations and fusions and has been partially implemented in clinical practice. However, standardized guidelines and criteria for the significance, application scenarios, and quality control of RNA-based NGS in fusion gene detection are still lacking in China. This consensus aims to provide further clarity on the practical significance, application scenarios, and quality control measures of RNA-based NGS in fusion gene detection. Additionally, it offers guiding recommendations to facilitate the clinical implementation of RNA-based NGS in the diagnosis and treatment of NSCLC, ultimately maximizing the benefits for patients from fusion gene detection.
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The Preclinical Pharmacology of Tepotinib-A Highly Selective MET Inhibitor with Activity in Tumors Harboring MET Alterations

The mesenchymal-epithelial transition factor (MET) proto-oncogene encodes the MET receptor tyrosine kinase. MET aberrations drive tumorigenesis in several cancer types through a variety of molecular mechanisms, including MET mutations, gene amplification, rearrangement, and overexpression. Therefore, MET is a therapeutic target and the selective type Ib MET inhibitor, tepotinib, was designed to potently inhibit MET kinase activity. In vitro, tepotinib inhibits MET in a concentration-dependent manner irrespective of the mode of MET activation, and in vivo, tepotinib exhibits marked, dose-dependent antitumor activity in MET-dependent tumor models of various cancer indications. Tepotinib penetrates the blood-brain barrier and demonstrates strong antitumor activity in subcutaneous and orthotopic brain metastasis models, in-line with clinical activity observed in patients. MET amplification is an established mechanism of resistance to EGFR tyrosine kinase inhibitors (TKI), and preclinical studies show that tepotinib in combination with EGFR TKIs can overcome this resistance. Tepotinib is currently approved for the treatment of adult patients with advanced or metastatic non-small cell lung cancer harboring MET exon 14 skipping alterations. This review focuses on the pharmacology of tepotinib in preclinical cancer models harboring MET alterations and demonstrates that strong adherence to the principles of the Pharmacological Audit Trail may result in a successful discovery and development of a precision medicine.

Identification of MET fusions in solid tumors: A multicenter, large scale study in China

MET amplification and exon 14 skipping are well known as oncogenic drivers in multiple cancer types. However, MET fusions in most cancer types are poorly defined. To explore the profile and analyze the characteristics of MET fusions, a large-cohort study was conducted to screen MET fusions in clinical samples (n = 10 882) using DNA-based NGS. A total of 37 potentially functional MET fusions containing the intact tyrosine kinase domain (TKD) of MET were identified in 36 samples. Further, 15 novel MET fusions were identified in five cancer types, and the incidence of novel MET fusions accounted for 40.5% (15/37). Brain cancer had the highest incidence of MET fusion, with PTPRZ1-MET as the most common fusion (37.0%). All MET breakpoints in brain cancer (n = 27) were also located in intron 1, while those in lung cancer (n = 4) occurred in intron 1, intron 11, intron 14 and exon 14, respectively. The positive consistency of the common fusion group was 100% (11/11), while that of the rare fusion group was 53.8% (7/13). In conclusion, we provided a comprehensive genomic landscape of MET rearrangement and updated the MET fusions database for clinical test. In addition, we revealed that DNA-based NGS might serve as the clinical test for common MET fusions; however, rare MET fusions must be validated by both DNA-based NGS and RNA-based NGS. Prospective trials are necessary to confirm the treatment efficacy of MET inhibitors.

Identification of MET fusions as novel therapeutic targets sensitive to MET inhibitors in lung cancer

INTRODUCTION

Alterations in the MET gene, including amplifications and exon 14 skipping mutations, have been identified as actionable oncogenic alterations. However, MET fusions are rarely detected in lung cancer, and their sensitivity to therapeutics has not been systematically analyzed.

METHODS

The data from 30876 lung cancer patients from the LAVA database and 7966 patients from cBioPortal database were screened. Basic demographic and clinical information for the patients harboring MET fusions were collected. A lung squamous cell cancer patient harboring a novel EML4-MET fusion was treated with crizotinib. Additionally, a literature review was performed to summarize the cases of patients harboring MET fusions and their treatment information.

RESULTS

MET fusions were found in only 0.2% to 0.3% of lung cancer patients and appeared in almost all exons of the MET gene. Intragenic MET fusions were found in 52.6% (41/78) of the included patients. Crizotinib was effective for MET fusions, including a novel identified EML4-MET fusion, even after the failure of multiple lines of treatment. This result suggested that acquired MET fusions become more regionally selective, as they usually occurred in exons encoding the extracellular region. Interestingly, the MET-fused genes in primary MET fusions or acquired MET fusions were very different, which indicated the different functions and influences of the disease.

CONCLUSION

MET fusions are rare, and half of the fusion types were intragenic fusions. Lung cancer patients harboring primary or acquired MET fusions could benefit from crizotinib. In addition, EML4-MET was first reported in this study as a novel MET fusion type.

Exposure-response analyses for the MET inhibitor tepotinib including patients in the pivotal VISION trial: support for dosage recommendations

Purpose

Tepotinib is a highly selective MET inhibitor approved for treatment of non-small cell lung cancer (NSCLC) harboring METex14 skipping alterations. Analyses presented herein evaluated the relationship between tepotinib exposure, and efficacy and safety outcomes.

Methods

Exposure–efficacy analyses included data from an ongoing phase 2 study (VISION) investigating 500 mg/day tepotinib in NSCLC harboring METex14 skipping alterations. Efficacy endpoints included objective response, duration of response, and progression-free survival. Exposure–safety analyses included data from VISION, plus four completed studies in advanced solid tumors/hepatocellular carcinoma (30–1400 mg). Safety endpoints included edema, serum albumin, creatinine, amylase, lipase, alanine aminotransferase, aspartate aminotransferase, and QT interval corrected using Fridericia’s method (QTcF).

Results

Tepotinib exhibited flat exposure–efficacy relationships for all endpoints within the exposure range observed with 500 mg/day. Tepotinib also exhibited flat exposure–safety relationships for all endpoints within the exposure range observed with 30–1400 mg doses. Edema is the most frequently reported adverse event and the most frequent cause of tepotinib dose reductions and interruptions; however, the effect plateaued at low exposures. Concentration-QTc analyses using data from 30 to 1400 mg tepotinib resulted in the upper bounds of the 90% confidence interval being less than 10 ms for the mean exposures at the therapeutic (500 mg) and supratherapeutic (1000 mg) doses.

Conclusions

These analyses provide important quantitative pharmacologic support for benefit/risk assessment of the 500 mg/day dosage of tepotinib as being appropriate for the treatment of NSCLC harboring METex14 skipping alterations.

Registration Numbers

NCT01014936, NCT01832506, NCT01988493, NCT02115373, NCT02864992.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00280-022-04441-3.

Case Report: Patient With Lung Adenocarcinoma With ALK-HLA-DRB1 Rearrangement Shows Impressive Progression-Free Survival After Sequential Crizotinib and Ceritinib Treatment

The anaplastic lymphoma kinase (ALK) gene rearrangement is a driving mutation that underlies about 5-6% of non-small cell lung cancer (NSCLC) cases. Lung cancers that are ALK gene rearrangement-positive can be effectively treated with ALK inhibitors. However, the response of patients with rarer ALK gene rearrangements to ALK inhibitors remains unknown. Herein, we described a case of lung adenocarcinoma carrying ALK-HLA-DRB1 fusion in a 48-year-old nonsmoking woman. A similar case of ALK-HLA-DRB1 rearrangement in NSCLC has not been described previously neither in NSCLC nor in other disease. The patient achieved a progression-free survival of 18 months after sequential therapy consisting of crizotinib and then ceritinib during the follow-up. These findings provide basis for the application of ALK inhibitors in patients carrying the rare ALK-HLA-DRB1 fusion.

Brain penetration and efficacy of tepotinib in orthotopic patient-derived xenograft models of MET-driven non-small cell lung cancer brain metastases

Central nervous system-penetrant therapies with intracranial efficacy against non-small cell lung cancer (NSCLC) brain metastases are urgently needed. We report preclinical studies investigating brain penetration and intracranial activity of the MET inhibitor tepotinib. After intravenous infusion of tepotinib in Wistar rats (n = 3), mean (±standard deviation) total tepotinib concentration was 2.87-fold higher in brain (505 ± 22 ng/g) than plasma (177 ± 20 ng/mL). In equilibrium dialysis experiments performed in triplicate, mean tepotinib unbound fraction was 0.35% at 0.3 and 3.0 µM tepotinib in rat brain tissue, and 4.0% at 0.3 and 1.0 µM tepotinib in rat plasma. The calculated unbound brain-to-plasma ratio was 0.25, indicating brain penetration sufficient for intracranial target inhibition. Of 20 screened subcutaneous patient-derived xenograft (PDX) models from lung cancer brain metastases (n = 1), two NSCLC brain metastases models (LU5349 and LU5406) were sensitive to the suboptimal dose of tepotinib of 30 mg/kg/qd (tumor volume change [%TV]: -12% and -88%, respectively). Molecular profiling (nCounter®; NanoString) revealed high-level MET amplification in both tumors (mean MET gene copy number: 11.2 and 24.2, respectively). Tepotinib sensitivity was confirmed for both subcutaneous models at a clinically relevant dose (125 mg/kg/qd; n = 5). LU5349 and LU5406 were orthotopically implanted into brains of mice and monitored by magnetic resonance imaging (MRI). Tepotinib 125 mg/kg/qd induced pronounced tumor regression, including complete or near-complete regressions, compared with vehicle in both orthotopic models (n = 10; median %TV: LU5349, -84%; LU5406, -63%). Intracranial antitumor activity of tepotinib did not appear to correlate with blood-brain barrier leakiness assessed in T1-weighted gadolinium contrast-enhanced MRI.

Receptor Tyrosine Kinases and Their Signaling Pathways as Therapeutic Targets of Curcumin in Cancer

Receptor tyrosine kinases (RTKs) are transmembrane cell-surface proteins that act as signal transducers. They regulate essential cellular processes like proliferation, apoptosis, differentiation and metabolism. RTK alteration occurs in a broad spectrum of cancers, emphasising its crucial role in cancer progression and as a suitable therapeutic target. The use of small molecule RTK inhibitors however, has been crippled by the emergence of resistance, highlighting the need for a pleiotropic anti-cancer agent that can replace or be used in combination with existing pharmacological agents to enhance treatment efficacy. Curcumin is an attractive therapeutic agent mainly due to its potent anti-cancer effects, extensive range of targets and minimal toxicity. Out of the numerous documented targets of curcumin, RTKs appear to be one of the main nodes of curcumin-mediated inhibition. Many studies have found that curcumin influences RTK activation and their downstream signaling pathways resulting in increased apoptosis, decreased proliferation and decreased migration in cancer both in vitro and in vivo. This review focused on how curcumin exhibits anti-cancer effects through inhibition of RTKs and downstream signaling pathways like the MAPK, PI3K/Akt, JAK/STAT, and NF-κB pathways. Combination studies of curcumin and RTK inhibitors were also analysed with emphasis on their common molecular targets.

Targeted Treatment of Non-Small Cell Lung Cancer: Focus on Capmatinib with Companion Diagnostics

MET dysregulation promoting tumorigenesis in non-small cell lung cancer (NSCLC) is associated with worse outcomes following chemotherapy as compared to non-driver mutated NSCLC and occurs either through mutations causing MET exon 14 skipping (METex14) or gene amplification and overexpression that result in enhanced receptor signaling. Capmatinib is the first FDA-approved targeted therapy for NSCLC with METex14 skipping mutations, approved in 2020. FoundationOne^® CDx, a comprehensive genomic profiling test for solid tumors, was concurrently approved as a companion diagnostic for capmatinib use. The GEOMETRY mono-1 phase II trial of capmatinib monotherapy demonstrated an overall response rate (ORR) of 68% in treatment naïve (n=28) and 41% in pre-treated (n=69) METex14 skipping advanced NSCLC; in MET amplified advanced NSCLC (gene copy number ≥ 10) ORRs of 40% in treatment naïve and 29% in pre-treated disease was seen. This review outlines the clinical data supporting capmatinib approval in the treatment of NSCLC and FoundationOne^® CDx approval as a companion diagnostic. We detail the practical clinical administration of capmatinib, including dosing and toxicity management, compare capmatinib to other approved and investigational MET-targeted therapies, discuss limitations of capmatinib, and highlight ongoing trials of capmatinib in combinatorial approaches.

Canadian Consensus Recommendations on the Management of MET-Altered NSCLC

In Canada, the therapeutic management of patients with advanced non-small cell lung cancer (NSCLC) with rare actionable mutations differs between provinces, territories, and individual centres based on access to molecular testing and funded treatments. These variations, together with the emergence of several novel mesenchymal-epithelial transition (MET) factor-targeted therapies for the treatment of NSCLC, warrant the development of evidence-based consensus recommendations for the use of these agents. A Canadian expert panel was convened to define key clinical questions, review evidence, discuss practice recommendations and reach consensus on the treatment of advanced MET-altered NSCLC. Questions addressed by the panel include: 1. How should the patients most likely to benefit from MET-targeted therapies be identified? 2. What are the preferred first-line and subsequent therapies for patients with MET exon 14 skipping mutations? 3. What are the preferred first-line and subsequent therapies for advanced NSCLC patients with de novo MET amplification? 4. What is the preferred therapy for patients with advanced epidermal growth factor receptor (EGFR)-mutated NSCLC with acquired MET amplification progressing on EGFR inhibitors? 5. What are the potential strategies for overcoming resistance to MET inhibitors? Answers to these questions, along with the consensus recommendations herein, will help streamline the management of MET-altered NSCLC in routine practice, assist clinicians in therapeutic decision-making, and help ensure optimal outcomes for NSCLC patients with MET alterations.

Advances in Lung Cancer Driver Genes Associated With Brain Metastasis

Brain metastasis, one of the common complications of lung cancer, is an important cause of death in patients with advanced cancer, despite progress in treatment strategies. Lung cancers with positive driver genes have higher incidence and risk of brain metastases, suggesting that driver events associated with these genes might be biomarkers to detect and prevent disease progression. Common lung cancer driver genes mainly encode receptor tyrosine kinases (RTKs), which are important internal signal molecules that interact with external signals. RTKs and their downstream signal pathways are crucial for tumor cell survival, invasion, and colonization in the brain. In addition, new tumor driver genes, which also encode important molecules closely related to the RTK signaling pathway, have been found to be closely related to the brain metastases of lung cancer. In this article, we reviewed the relationship between lung cancer driver genes and brain metastasis, and summarized the mechanism of driver gene-associated pathways in brain metastasis. By understanding the molecular characteristics during brain metastasis, we can better stratify lung cancer patients and alert those at high risk of brain metastasis, which helps to promote individual therapy for lung cancer.