Recording and classifying MET receptor mutations in cancers

Tyrosine kinase inhibitors (TKI) directed against MET have been recently approved to treat advanced non-small cell lung cancer (NSCLC) harbouring activating MET mutations. This success is the consequence of a long characterization of MET mutations in cancers, which we propose to outline in this review. MET, a receptor tyrosine kinase (RTK), displays in a broad panel of cancers many deregulations liable to promote tumour progression. The first MET mutation was discovered in 1997, in hereditary papillary renal cancer (HPRC), providing the first direct link between MET mutations and cancer development. As in other RTKs, these mutations are located in the kinase domain, leading in most cases to ligand-independent MET activation. In 2014, novel MET mutations were identified in several advanced cancers, including lung cancers. These mutations alter splice sites of exon 14, causing in-frame exon 14 skipping and deletion of a regulatory domain. Because these mutations are not located in the kinase domain, they are original and their mode of action has yet to be fully elucidated. Less than five years after the discovery of such mutations, the efficacy of a MET TKI was evidenced in NSCLC patients displaying MET exon 14 skipping. Yet its use led to a resistance mechanism involving acquisition of novel and already characterized MET mutations. Furthermore, novel somatic MET mutations are constantly being discovered. The challenge is no longer to identify them but to characterize them in order to predict their transforming activity and their sensitivity or resistance to MET TKIs, in order to adapt treatment.

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.

Real-World Data on Combined EGFR-TKI and Crizotinib Treatment for Acquired and De Novo MET Amplification in Patients with Metastatic EGFR-Mutated NSCLC

Amplification of the mesenchymal epithelial transition (MET) gene is a mechanism of acquired resistance to epidermal growth factor receptor (EGFR)-tyrosine-kinase-inhibitors (TKIs) in over 20% of patients with advanced EGFR-mutated (EGFRm+) non-small lung cancer (NSCLC). However, it may also occur de novo in 2-8% of EGFRm+ NSCLC cases as a potential mechanism of intrinsic resistance. These patients represent a group with unmet needs, since there is no standard therapy currently approved. Several new MET inhibitors are being investigated in clinical trials, but the results are awaited. Meanwhile, as an alternative strategy, combinations of EGFR-TKIs with the MET/ALK/ROS1-TKI Crizotinib may be used in this setting, despite this use is principally off-label. Thus, we studied five of these MET amplified cases receiving EGFR-TKI and Crizotinib doublet after progression on EGFR-TKI treatment to assess the benefits and challenges related to this combination and the possible occurrence of genomic and phenotypic co-alterations. Furthermore, we compared our cases with other real-world reports on Crizotinib/EGFR-TKI combinations, which appeared effective, especially in patients with high-level MET amplification. Yet, we observed that the co-occurrence of other genomic and phenotypical alterations may affect the response to combined EGFR-TKI and Crizotinib. Finally, given the heterogeneity of MET amplification, the diagnostic methods for assessing it may be discrepant. In this respect, we observed that for optimal detection, immunohistochemistry, fluorescence in situ hybridization, and next-generation sequencing should be used together, as these methods possess different sensitivities and complement each other in characterizing MET amplification. Additionally, we addressed the issue of managing EGFR-mutated NSCLC patients with de novo MET amplification causing primary EGFR-TKI resistance. We conclude that, while data from clinical trials with new MET inhibitors are still pending, adding Crizotinib to EGFR-TKI in NSCLC patients acquiring MET amplification at progression on EGFR-TKI monotherapy is a reasonable approach, with a progression-free survival of 3-19 months.

Real-World Treatment Outcomes of MET Exon14 Skipping in Non-small Cell Lung Cancer: GFPC 03-18 Study

BACKGROUND

MET-targeted tyrosine kinase inhibitors (TKIs) demonstrated efficacy in advanced non-small cell lung cancer (aNSCLC) with MET exon14 skipping mutations (METexon14); yet, data on the management of these patients in clinical practice is sparse.

OBJECTIVE

The aim of this study was to describe the management of METexon14 aNSCLC patients.

PATIENTS AND METHODS

This real-life, retrospective study analyzed the management of METexon14 aNSCLC. The primary endpoint was the median overall survival (mOS). Secondary endpoints were to assess investigator-progression-free survival (PFS) and mOS in different subgroups: patients treated with (a) crizotinib, regardless of treatment line; (b) anti-MET TKIs (crizotinib, tepotinib, capmatinib); and (c) immunotherapy.

RESULTS

A total of 118 patients were included between December 2015 and January 1, 2020 in 13 centers. Median age was 73 years, 62.7% were female, 83.9% had adenocarcinoma, 92.4% at stage IV, and 27% had more than three metastatic sites. The majority of the patients (106, 89.8%) received at least one systemic treatment; 73% received at least one anti-MET TKI: crizotinib (68.6%), tepotinib (16%), capmatinib (10%). Only 10% received two anti-MET TKIs in their treatment sequences. With a median follow-up of 16 months (95% CI 13.6-29.7), mOS was 27.1 months (95% CI 18-31.4). There was no significant difference between mOS of patients treated and never treated with crizotinib, 19.7 (95% CI 13.6-29.7) and 28 (95% CI 16.4-NR) months, respectively (p = 0.16); mOS of the TKI cohort and of the TKI-naïve patient cohort were 27.1 (95% CI 18-29.7) and 35.6 (95% CI 8.6-NR) months respectively, with no significant difference (p = 0.7).

CONCLUSIONS

In this real-life study, there was no evidence of benefit in mOS with anti-MET TKIs.

A Systematic Review of the Cost-Effectiveness Analyses of Anaplastic Lymphoma Kinase (ALK) Inhibitors in Patients with Locally Advanced or Metastatic Non-small Cell Lung Cancer (NSCLC)

BACKGROUND

The anaplastic lymphoma kinase (ALK) inhibitor treatment landscape is rapidly evolving, providing patients with ALK-positive (+) non-small cell lung cancer (NSCLC) with multiple therapy options, multiple lines of treatments, and prolonged survival. However, these recent treatment advances have resulted in additional increases in treatment costs. The objective of this article is to review the economic evidence of ALK inhibitors in patients with ALK+ NSCLC.

METHODS

The systematic review was conducted in accordance with the Joanna Briggs Institute (JBI) systematic reviews of economic evaluation. The population included adult patients with locally advanced (stage IIIb/c) or metastatic (stage IV) NSCLC cancer with confirmed ALK fusions. The interventions included the ALK inhibitors alectinib, brigatinib, ceritinib, crizotinib, ensartinib, or lorlatinib. The comparators included the listed ALK inhibitors, chemotherapy, or best supportive care. The review considered cost-effectiveness analysis studies (CEAs) that reported incremental cost-effectiveness ratio in quality-adjusted life years and/or in life years gained. Published literature was searched in Medline (via Ovid) by 4 January 2023, in Embase (via Ovid) by 4 January 2023, in International Pharmaceutical Abstracts (via Ovid) by 4 January 2023, and in Cochrane library (via Wiley) by 11 January 2023. Preliminary screening of titles and abstracts was conducted against the inclusion criteria by two independent researchers followed by a full text of selected citations. Search results are presented in a Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) flow diagram. Critical appraisal was conducted using the validated Consolidated Health Economic Evaluation Reporting Standards 2022 (CHEERS) tool as well as the Phillips et al. 2004 appraisal tool to assess the reporting and quality of the economic evaluations. Data were extracted from the final set of articles and presented in a table of characteristics of included studies, an overview of study methods of included studies, and a summarization of outcomes of included studies.

RESULTS

A total of 19 studies met all inclusion criteria. The majority of the studies were in the first-line treatment setting (n = 15). Included CEAs varied in the interventions and comparators being evaluated and were conducted from different country perspectives, limiting their comparability. Outcomes from the included CEAs showed that ALK inhibitors may be considered a cost-effective treatment option for patients with ALK+ NSCLC in the first-line and subsequent lines of treatment setting. However, the probability of cost effectiveness of ALK inhibitors ranged from 46 to 100% and were mostly achieved at willingness-to-pay thresholds of $100,000 USD or higher (> $30,000 or higher in China) in the first-line treatment setting and at thresholds of $50,000 USD or higher in subsequent lines of treatment setting. The number of published full-text CEAs is low and the studies represent a handful of country perspectives. The source of survival data was dependent on data from randomized controlled trials (RCTs). Where RCT data were not available, indirect treatment comparisons or matched adjusted indirect comparisons were performed using efficacy data from different clinical studies. Real world evidence was rarely used for efficacy and costing data inputs.

CONCLUSION

The findings summarized available evidence on cost effectiveness of ALK inhibitors for the treatment of patients with locally advanced or metastatic ALK+ NSCLC across lines of treatment settings and generated a valuable overview of analytical approaches utilized to support future economic analyses. To help further inform treatment and policy decisions, this review emphasizes the need for comparative cost effectiveness of multiple ALK inhibitors simultaneously using real-world data sources with broad representation of settings.

Targeted Toxicities: Protocols for Monitoring the Adverse Events of Targeted Therapies Used in the Treatment of Non-Small Cell Lung Cancer

Targeted therapies have revolutionized the treatment for many patients with non-small cell lung cancer (NSCLC). Multiple new oral targeted therapies have been approved in the last decade; however, their overall efficacy may be reduced by poor adherence, treatment interruptions, or dose reductions due to adverse events. Most institutions lack standard monitoring protocols for toxicities from these targeted agents. This review describes important adverse events observed in clinical trials and reported by the U.S. Food and Drug Administration for both currently approved and upcoming promising therapies in the treatment of NSCLC. These agents cause a range of toxicities, including dermatologic, gastroenteric, pulmonary, and cardiac toxicities. This review proposes protocols for routine monitoring of these adverse events, both prior to initiation of therapy and while on treatment.

Crizotinib efficacy and safety in patients with advanced NSCLC harboring MET alterations: A real-life data of Turkish Oncology Group

Crizotinib is a multikinase inhibitor, effective in non-small cell lung cancer (NSCLC) harboring mesenchymal-epidermal transition (MET) alterations. Although small prospective studies showed efficacy and safety of crizotinib in NSCLC with MET alterations, there is limited real-life data. Aim of this study is to investigate real-life efficacy and safety of crizotinib in patients with advanced NSCLC harboring MET alterations. This was a retrospective, multicenter (17 centers) study of Turkish Oncology Group. Patients' demographic, histological data, treatment, response rates, survival outcomes, and toxicity data were collected. Outcomes were presented for the study population and compared between MET alteration types. Total of 62 patients were included with a median age of 58.5 (range, 26-78). Major histological type was adenocarcinoma, and 3 patients (4.8%) had sarcomatoid component. The most common MET analyzing method was next generation sequencing (90.3%). MET amplification and mutation frequencies were 53.2% (n = 33) and 46.8% (n = 29), respectively. Overall response rate and disease control rate were 56.5% and 74.2% in whole study population, respectively. Median progression free survival (PFS) was 7.2 months (95% confidence interval [CI]: 3.8-10.5), and median overall survival (OS) was 18.7 months (95% CI: 13.7-23.7), regardless of treatment line. Median PFS was 6.1 months (95% CI: 5.6-6.4) for patients with MET amplification, whereas 14.3 months (95% CI: 6.7-21.7) for patients with MET mutation (P = .217). Median PFS was significantly longer in patients who have never smoked (P = .040), have good performance score (P < .001), and responded to the treatment (P < .001). OS was significantly longer in patients with MET mutation (25.6 months, 95% CI: 15.9-35.3) compared to the patients with MET amplification (11.0 months; 95% CI: 5.2-16.8) (P = .049). In never-smokers, median OS was longer than smoker patients (25.6 months [95% CI: 11.8-39.3] vs 16.5 months [95% CI: 9.3-23.6]; P = .049). The most common adverse effects were fatigue (50%), peripheral edema (21%), nausea (29%) and diarrhea (19.4%). Grade 3 or 4 adverse effects were observed in 6.5% of the patients. This real-life data confirms efficacy and safety of crizotinib in the treatment of advanced NSCLC harboring MET alteration.

MET Signaling Pathways, Resistance Mechanisms, and Opportunities for Target Therapies

The MET gene, known as MET proto-oncogene receptor tyrosine kinase, was first identified to induce tumor cell migration, invasion, and proliferation/survival through canonical RAS-CDC42-PAK-Rho kinase, RAS-MAPK, PI3K-AKT-mTOR, and β-catenin signaling pathways, and its driver mutations, such as MET gene amplification (METamp) and the exon 14 skipping alterations (METex14), activate cell transformation, cancer progression, and worse patient prognosis, principally in lung cancer through the overactivation of their own oncogenic and MET parallel signaling pathways. Because of this, MET driver alterations have become of interest in lung adenocarcinomas since the FDA approval of target therapies for METamp and METex14 in 2020. However, after using MET target therapies, tumor cells develop adaptative changes, favoring tumor resistance to drugs, the main current challenge to precision medicine. Here, we review a link between the resistance mechanism and MET signaling pathways, which is not only limited to MET. The resistance impacts MET parallel tyrosine kinase receptors and signals shared hubs. Therefore, this information could be relevant in the patient's mutational profile evaluation before the first target therapy prescription and follow-up to reduce the risk of drug resistance. However, to develop a resistance mechanism to a MET inhibitor, patients must have access to the drugs. For instance, none of the FDA approved MET inhibitors are registered as such in Chile and other developing countries. Constant cross-feeding between basic and clinical research will thus be required to meet future challenges imposed by the acquired resistance to targeted therapies.

Molecular Characteristics of Radon Associated Lung Cancer Highlights MET Alterations

Simple Summary

Lung cancer (LC) is the leading cause of cancer death worldwide. After smoking, one of the most prominent risk factors for LC development is radon (Rn) exposure. In our study we analysed and compared the genetic landscape of LC patients from a Rn exposed village with local matched non-exposed patients. Within the concordant genetic landscape, an increase in genetic MET proto-oncogene, receptor tyrosine kinase (MET) alteration in the Rn-exposed cohort was monitored, underlining the importance of routine MET testing and potential to enable a more effective treatment for this specific subgroup.

Abstract

Effective targeted treatment strategies resulted from molecular profiling of lung cancer with distinct prevalent mutation profiles in smokers and non-smokers. Although Rn is the second most important risk factor, data for Rn-dependent driver events are limited. Therefore, a Rn-exposed cohort of lung cancer patients was screened for oncogenic drivers and their survival and genetic profiles were compared with data of the average regional population. Genetic alterations were analysed in 20 Rn-exposed and 22 histologically matched non-Rn exposed LC patients using targeted Next generation sequencing (NGS) and Fluorescence In Situ Hybridization (FISH). Sufficient material and sample quality could be obtained in 14/27 non-exposed versus 17/22 Rn-exposed LC samples. Survival was analysed in comparison to a histologically and stage-matched regional non-exposed lung cancer cohort (n = 51) for hypothesis generating. Median overall survivals were 83.02 months in the Rn-exposed and 38.7 months in the non-exposed lung cancer cohort (p = 0.22). Genetic alterations of both patient cohorts were in high concordance, except for an increase in MET alterations and a decrease in TP53 mutations in the Rn-exposed patients in this small hypothesis generating study.

Mutational Landscape and Expression of PD-L1 in Patients with Non-Small Cell Lung Cancer Harboring Genomic Alterations of the MET gene

Background

Mesenchymal-to-epithelial transition (MET) exon 14 skipping mutations and MET gene amplification occur in 3–5% of non-small cell lung cancer (NSCLC) patients. Tyrosine kinase inhibitors (TKIs) targeting MET alterations have shown promising results in these patients.

Objective

The aim of this study was to describe the genomic profile, PD-L1 expression and clinicopathological features of MET dysregulated NSCLC.

Patients and Methods

We identified 188 patients with advanced-stage NSCLC with data on MET expression by immunohistochemistry (IHC). IHC for PD-L1 expression was performed in 131 patient samples, and next-generation sequencing (NGS) analysis was performed in 109 patient samples.

Results

MET exon 14 skipping alterations were identified in 16 (14.7%) samples, MET amplifications with cut-off ≥4 copy number variations were identified in 11 (10.1%) samples, and an oncogenic MET mutation (MET p.D1228N) was identified in 1 (0.9%) sample. 12/15 tumors (80.0%) harboring MET exon 14 alterations and 7/11 (63.6%) MET-amplified tumors expressed PD-L1 in ≥1% of tumor cells. Tumors harboring MET exon 14 skipping alterations expressed PD-L1 more frequently than MET wild-type IHC-positive tumors (p = 0.045). Twenty-five percent of MET exon 14-altered cases and 33% of MET-amplified cases harbored potentially targetable oncogenic co-mutations in KRAS, BRAF, and EGFR. The most frequent co-occurring mutations in all MET-altered tumors were TP53, KRAS, BRAF, and CDK4.

Conclusions

We demonstrated that MET exon 14 skipping alterations and MET amplification are not mutually exclusive to other oncogenic co-mutations, and report the association of genomic MET alterations with PD-L1 expression. Since genomic MET alterations are emerging targets requiring upfront treatment, optimal understanding of the co-mutational landscape for this patient population is needed.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11523-022-00918-6.

MET Exon 14 Splice-Site Mutations Preferentially Activate KRAS Signaling to Drive Tumourigenesis

Simple Summary

MET exon 14 splice-site mutations occur in ~3–4% of lung adenocarcinoma cases, defining a cohort of patients which might benefit from anti-MET targeted therapy. Such therapies have yielded mixed results, however, pointing to the need for better treatment design. Our study sought to aid this by characterizing key changes in mutant MET signaling behaviour. We first compared the transcriptional profiles of lung tumours with either METΔex14 or wild-type MET-amplification. METΔex14-mutant tumours exhibited increased activation of the Ras-MAPK pathway, consistent with our observations in an isogenic model system. Furthermore, sustained activity of this pathway is necessary for proliferation and maintenance of METΔex14 tumours, while forced reactivation of this pathway is sufficient to restore growth in the absence of MET activity. Our findings suggest that the MAPK pathway represents a main effector of METΔex14-driven cancer, lending credence to the possibility of combined MET-MAPK inhibition to improve therapeutic outcomes.

Abstract

Targeted therapies for MET exon 14-skipping (METΔex14)-driven lung cancers have generated some promising results but response rates remain below that seen for other kinase-driven cancers. One strategy for improving treatment outcomes is to employ rational combination therapies to enhance the suppression of tumour growth and delay or prevent the emergence of resistance. To this end, we profiled the transcriptomes of MET-addicted lung tumours and cell lines and identified the RAS-mitogen-activated protein kinase (MAPK) pathway as a critical effector required for METΔex14-dependent growth. Ectopic expression of MET in an isogenic cell line model showed that overexpression of the mutant MET receptor led to higher levels of MAPK phosphorylation and nuclear import, resulting in increased expression and phosphorylation of nuclear MAPK targets. In comparison, other known MET effectors were unaffected. Inhibition of this pathway by KRAS knockdown in MET-addicted cells in vitro led to decreased viability in only the METΔex14-mutant cells. Conversely, decoupling RAS-MAPK axis, but not other effector pathways, from MET activity via the introduction of constitutively active mutants conferred resistance to MET inhibitors in vitro. Our results suggest that aberrant hyperactivity of the MET receptor caused by the exon 14-skipping mutation does not uniformly upregulate all known downstream effectors, rather gaining a predilection for aberrantly activating and subsequently relying on the RAS-MAPK pathway. These findings provide a rationale for the co-targeting of the RAS-MAPK pathway alongside MET to prolong therapeutic response and circumvent resistance to improve patient survival.

Targeted Therapy for Older Patients with Non-Small Cell Lung Cancer: Systematic Review and Guidelines from the French Society of Geriatric Oncology (SoFOG) and the French-Language Society of Pulmonology (SPLF)/French-Language Oncology Group (GOLF)

Simple Summary

Targeted therapy has become essential in the treatment of non-small cell lung cancer (NSCLC). There are currently no guidelines for older patients who are frailer with regard to this type of treatment. Two learned societies, the French Society of Geriatric Oncology (SoFOG) and the French-language Society of Pulmonology (SPLF)/French-language Oncology Group (GOLF), joined forces to conduct a systematic review of the literature from May 2010 to May 2021 regarding the efficacy, toxicity, and feasibility of targeted therapy in older patients with NSCLC. Guidelines were then drawn up to enable clinicians to adapt the type of targeted therapy proposed according to the oncological and geriatric profile of the older patient with NSCLC.

Abstract

Systematic molecular profiling and targeted therapy (TKI) have changed the face of Non-Small Cell Lung Cancer (NSCLC) treatment. However, there are no specific recommendations to address the prescription of TKI for older patients. A multidisciplinary task force from the French Society of Geriatric Oncology (SoFOG) and the French Society of Pulmonology/Oncology Group (SPLF/GOLF) conducted a systematic review from May 2010 to May 2021. Protocol registered in Prospero under number CRD42021224103. Three key questions were selected for older patients with NSCLC: (1) to whom TKI can be proposed, (2) for whom monotherapy should be favored, and (3) to whom a combination of TKI can be proposed. Among the 534 references isolated, 52 were included for the guidelines. The expert panel analysis concluded: (1) osimertinib 80 mg/day is recommended as a first-line treatment for older patients with the EGFR mutation; (2) full-dose first generation TKI, such as erlotinib or gefitinib, is feasible; (3) ALK and ROS1 rearrangement studies including older patients were too scarce to conclude on any definitive recommendations; and (4) given the actual data, TKI should be prescribed as monotherapy. Malnutrition, functional decline, and the number of comorbidities should be assessed primarily before TKI initiation.

Case Report: A 91-Year-Old Patient With Non-Small Cell Lung Cancer Harboring MET Y1003S Point Mutation

Background

The Y1003S point mutation in exon 14 of mesenchymal-epithelial transition (MET) is a rare mutation that can lead to oncogenic transformation. Few data are available on the characteristics of this mutation. This report presents an elderly patient with non-small cell lung cancer (NSCLC) and a Y1003S mutation in MET detected by next-generation sequencing (NGS).

Case Report

In October 2020, a 91-year-old male was admitted to the Department of Respiratory and Critical Care Medicine, Ruijin Hospital because of an increased carcinoembryonic antigen. Imaging revealed highly suspicious lesions in the right upper lobe of the lung, right apex, and left upper lobe with traction of the adjacent pleura. The patient was histologically confirmed as having adenocarcinoma and the MET Y1003S mutation was detected by the NGS subsequently. After evaluation, the patient started crizotinib treatment in December 2020. In the first assessment of tumor response, a chest CT scan in January 2021 showed a partial response. The patient experienced a pulmonary embolism and an abnormal liver function during the treatment and recovered after symptomatic treatment. He maintained a partial response in the last available assessment in July 2021, with the right upper lung lesion being 26 × 9 mm.

Conclusion

The MET Y1003S mutation was detected in this case, and the patient achieved a partial response using crizotinib. This case highlighted the role of NGS in detecting a rare mutation. Successful remission of complications in such an elderly patient necessitates careful and timely management.

Phase I Study of 2- or 3-Week Dosing of Telisotuzumab Vedotin, an Antibody-Drug Conjugate Targeting c-Met, Monotherapy in Patients with Advanced Non-Small Cell Lung Carcinoma

PURPOSE

Telisotuzumab vedotin (Teliso-V) is an anti-c-Met-directed antibody-drug conjugate. Here, we present safety and efficacy data from a phase I/Ib study of Teliso-V monotherapy evaluated in once every 2 weeks/once every 3 weeks schedules in patients with non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

During dose escalation, patients received Teliso-V monotherapy intravenously once every 3 weeks (0.15-3.3 mg/kg) or once every 2 weeks (1.6-2.2 mg/kg). The dose-expansion phase enrolled patients with NSCLC and c-Met H-score ≥150 (c-Met+) or MET amplification/exon 14 skipping mutations. Safety, pharmacokinetics, and efficacy were assessed. Herein, the analysis of patients receiving ≥1.6 mg/kg once every 2 weeks or ≥2.4 mg/kg once every 3 weeks Teliso-V is reported.

RESULTS

Fifty-two patients with NSCLC were enrolled and received ≥1.6 mg/kg Teliso-V once every 2 weeks (n = 28) or ≥2.4 mg/kg Teliso-V once every 3 weeks (n = 24). The most common adverse events were fatigue (54%), peripheral neuropathy (42%), and nausea (38%). No dose-limiting toxicities were observed for Teliso-V once every 2 weeks and once every 3 weeks up to 2.2 and 2.7 mg/kg, respectively. The recommended phase II dose was established at 1.9 mg/kg once every 2 weeks and 2.7 mg/kg once every 3 weeks on the basis of overall safety and pharmacokinetics. Forty of 52 patients were c-Met+ (33 nonsquamous, 6 squamous, 1 mixed histology) and were included in the efficacy-evaluable population. Of those, 9 (23%) had objective responses with median duration of response of 8.7 months; median progression-free survival was 5.2 months.

CONCLUSIONS

Teliso-V monotherapy was tolerated and showed antitumor activity in c-Met+ NSCLC. On the basis of overall safety, pharmacokinetics, and efficacy outcomes, 1.9 mg/kg Teliso-V once every 2 weeks and 2.7 mg/kg once every 3 weeks schedules were selected for further clinical development.

HGF/c-MET pathway in cancer: from molecular characterization to clinical evidence

This review provides a comprehensive landscape of HGF/c-MET (hepatocyte growth factor (HGF) /mesenchymal-epithelial transition factor (c-MET)) signaling pathway in cancers. First, we generalize the compelling influence of HGF/c-MET pathway on multiple cellular processes. Then, we present the genomic characterization of HGF/c-MET pathway in carcinogenesis. Furthermore, we extensively illustrate the malignant biological behaviors of HGF/c-MET pathway in cancers, in which hyperactive HGF/c-MET signaling is considered as a hallmark. In addition, we investigate the current clinical trials of HGF/c-MET-targeted therapy in cancers. We find that although HGF/c-MET-targeted therapy has led to breakthroughs in certain cancers, monotherapy of targeting HGF/c-MET has failed to demonstrate significant clinical efficacy in most cancers. With the advantage of the combinations of HGF/c-MET-targeted therapy, the exploration of more options of combinational targeted therapy in cancers may be the major challenge in the future.

Treatment of Rare Mutations in Patients with Lung Cancer

Lung cancer is a worldwide prevalent malignancy. This disease has a low survival rate due to diagnosis at a late stage challenged by the involvement of metastatic sites. Non-small-cell lung cancer (NSCLC) is presented in 85% of cases. The last decade has experienced substantial advancements in scientific research, leading to a novel targeted therapeutic approach. The newly developed pharmaceutical agents are aimed towards specific mutations, detected in individual patients inflicted by lung cancer. These drugs have longer and improved response rates compared to traditional chemotherapy. Recent studies were able to identify rare mutations found in pulmonary tumors. Among the gene alterations detected were mesenchymal epithelial transition factor (MET), human epidermal growth factor 2 (HER2), B-type Raf kinase (BRAF), c-ROS proto-oncogene (ROS1), rearranged during transfection (RET) and neurotrophic tyrosine kinase (NTRK). Ongoing clinical trials are gaining insight onto possible first and second lines of medical treatment options intended to enable progression-free survival to lung cancer patients.

An improved assay for detection of theranostic gene translocations and MET exon 14 skipping in thoracic oncology

Theranostic translocations may be difficult to detect by routine techniques, especially when specimens are exiguous. We recently demonstrated in a series of translocated lung adenocarcinomas that LD-RT-PCR (ligation-dependent reverse transcription polymerase chain reaction) assay could identify ALK, ROS1 and RET rearrangements with 64% sensitivity and 100% specificity. Here, we report an upgraded version of this assay used in a routine prospective cohort of lung carcinomas. Newly diagnosed lung carcinomas referred to the Rouen molecular platform between 15/05/2018 and 15/05/2019 for ALK and ROS1 IHC, genotyping (SNaPshot© +/- high-throughput genotyping) and sometimes FISH (standard routine process) were tested prospectively in parallel with the LD-RT-PCR assay designed to detect at one go ALK, ROS1 and RET translocations and MET exon 14 skipping. 413 tumors from 396 patients were included. LD-RT-PCR had a global sensitivity of 91.43% (standard routine process: 80%), with a specificity of 100%. It detected 15/18 ALK and 4/4 ROS1 translocated tumors, but also 6/6 tumors with MET exon 14 skipping retrieved by genotyping. In addition, it retrieved 7 alterations missed by the routine process, then confirmed by other means: 5 MET exon 14 skipping and 2 RET translocated tumors. Finally, it allowed to deny an effect on MET exon 14 skipping for 8 mutations detected by routine genotyping. We successfully implemented LD-RT-PCR in routine analysis. This technique is cheap, fast, sensitive, specific, and easily upgradable (e.g., NTRK translocations), but still requires IHC to be performed in parallel. Owing to its advantages, we recommend considering it, in parallel with IHC and genotyping, as an excellent cost-effective alternative, for the systematic testing of lung adenocarcinoma, to FISH and to more expensive and complex assays such as RNA-seq.

Crizotinib for c-MET-amplified advanced NSCLC: a single-center experience

INTRODUCTION

Lung cancer is the most common cause of cancer-related death in the world. Changes in the treatment of metastatic lung cancer in recent years have made targetable mutations gain importance. MET alteration is one of these driver mutations and crizotinib is a tyrosine kinase inhibitor used in therapy.

METHODS

In our study, data of patients with c-MET amplification who received crizotinib treatment between July 2017 and November 2020 in the Medical Oncology Clinic of Bakırköy Dr. Sadi Konuk Training and Research Hospital were retrospectively analyzed. c-MET scanning was performed by the fluorescent in situ hybridization method by using Cytotest MET/CCP7 probe kit by evaluating 100 tumor cells and the threshold value for positivity was accepted as above 20%.

RESULTS

Eight of 28 patients who received crizotinib treatment had c-MET amplification. Seven of these patients were male and one was female. Progression-free survival and overall survival in these eight patients were 9.4 and 10.9 months, respectively, and objective response rate was 50%. Grade 4 nausea was observed in only one patient; there was no grade 4-5 toxicity and no patient discontinued the drug due to toxicity.

CONCLUSION

Crizotinib is an effective treatment option other than cytotoxic chemotherapy in the limited number of patients with MET amplification in the stage 4 lung adenocarcinoma subgroup. It is important to investigate this amplification, which can be detected especially in smoking patients in the appropriate patient group, and to use appropriate tyrosine kinase inhibitors in treatment.

Uncommon targets in non-small cell lung cancer: Everyone wants a slice of cake

Target therapies completely changed the clinical approach in EGFR mutated and ALK rearranged non-small cell lung cancer, ensuring these patients exceptional outcomes with a better toxicity profile compared to conventional chemotherapy. In recent years, beyond EGFR and ALK alterations, new data are emerging about less common alterations, new drugs have been already approved and others agents have been recently investigated or are currently under investigation. In this review we will discuss some uncommon alterations in non-small cell lung cancer such as ROS1, BRAF, RET, HER2, NTRK, MET and other targets that are in an early evaluation phase. We will summarize the characteristics of patients harboring these alterations, the already approved or under investigation therapies and the related resistance mechanisms.

Novel Emerging Molecular Targets in Non-Small Cell Lung Cancer

In the scenario of systemic treatment for advanced non-small cell lung cancer (NSCLC) patients, one of the most relevant breakthroughs is represented by targeted therapies. Throughout the last years, inhibitors of the epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), c-Ros oncogene 1 (ROS1), and V-raf murine sarcoma viral oncogene homolog B (BRAF) have been approved and are currently used in clinical practice. However, other promising molecular drivers are rapidly emerging as therapeutic targets. This review aims to cover the molecular alterations with a potential clinical impact in NSCLC, including amplifications or mutations of the mesenchymal–epithelial transition factor (MET), fusions of rearranged during transfection (RET), rearrangements of the neurotrophic tyrosine kinase (NTRK) genes, mutations of the Kirsten rat sarcoma viral oncogene (KRAS) and phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA), as well as amplifications or mutations of human epidermal growth factor receptor 2 (HER2). Additionally, we summarized the current status of targeted agents under investigation for such alterations. This revision of the current literature on emerging molecular targets is needed as the evolving knowledge on novel actionable oncogenic drivers and targeted agents is expected to increase the proportion of patients who will benefit from tailored therapeutic approaches.

Targeted Therapy Approaches for MET Abnormalities in Non-Small Cell Lung Cancer

The tyrosine kinase receptor mesenchymal epithelial transition (MET) is a proto-oncogene that, through the activation of the MET-hepatocyte growth factor (HGF) pathway, encodes a variety of biological processes, including cell development, proliferation, invasion, and migration. Abnormal activation of the MET pathway, occurring through MET protein overexpression, and gene amplification or mutation, can contribute to oncogenesis and has been implicated in non-small cell lung cancer (NSCLC). Though it is associated with poor clinical outcome in NSCLCs, MET overexpression and its role as a therapeutic target remains somewhat elusive due to discrepancies in its occurrence. Unlike MET overexpression, MET amplification has demonstrated a stronger potential as a biomarker for therapeutic treatment, with clinical data indicating a compelling connection between a high MET gene copy number and a high response rate to targeted therapies. However, MET exon 14 skipping mutations, occurring in 3%-4 % of lung adenocarcinomas, are of particular interest, as tumors harboring these mutations have shown a significant response to MET inhibitors. Following the discovery of MET as a potential therapeutic target, extensive clinical studies have proposed three approaches to targeting MET: (1) MET tyrosine kinase inhibitors (TKIs), including crizotinib, capmatinib, tepotinib, savolinitib, and cabozantinib; (2) MET or HGF monoclonal antibodies, including emibetuzumab and ficlatuzumab; and (3) MET or HGF antibody drug conjugates, including telisotuzumab. Herein, we discuss the relevant clinical trials, particularly focusing on the efficacy as well as the safety and tolerability of the treatment options, in the promising field of targeting MET in NSCLC.

Targeting MET Amplification with Crizotinib in a Case of Sinonasal Undifferentiated Carcinoma

Comprehensive molecular testing of individual tumors has led to the identification of novel molecularly defined cancer therapies and treatment indications. Given low frequencies of many molecular alterations, efficacy of therapies used to target them are often undefined, especially in the context of rare malignancies. Here we describe the first reported case of MET amplification in sinonasal undifferentiated carcinoma (SNUC), a rare cancer with a poor prognosis. The patient was treated with crizotinib, a tyrosine kinase inhibitor that targets c-MET, and experienced a complete response. Our report demonstrates the potential of employing precision oncology approaches in SNUC and other rare cancers.

Breakthrough in targeted therapy for non-small cell lung cancer

Non-small cell lung cancer (NSCLC) remains by far the single most common malignancy of lung cancer which causes more and more mortality in recent years. NSCLC accounts for more than 80 % of lung cancers, and the vast majority of patients were found to be in advanced inoperable stages. Chemotherapy used to be the main treatment for NSCLC, but due to its obvious side effects. Chemotherapy gradually withdrew from the stage of history. In recent years, cellular and molecular biotechnology has developed rapidly, and researchers have begun to target key genes and regulatory molecules for treatment. Targeted drugs have also emerged. The purpose of this review is to introduce important research achievements in recent years and the treatment progress of new drugs.

Tyrosine Kinase Receptors in Oncology

Tyrosine kinase receptors (TKR) comprise more than 60 molecules that play an essential role in the molecular pathways, leading to cell survival and differentiation. Consequently, genetic alterations of TKRs may lead to tumorigenesis and, therefore, cancer development. The discovery and improvement of tyrosine kinase inhibitors (TKI) against TKRs have entailed an important step in the knowledge-expansion of tumor physiopathology as well as an improvement in the cancer treatment based on molecular alterations over many tumor types. The purpose of this review is to provide a comprehensive review of the different families of TKRs and their role in the expansion of tumor cells and how TKIs can stop these pathways to tumorigenesis, in combination or not with other therapies. The increasing growth of this landscape is driving us to strengthen the development of precision oncology with clinical trials based on molecular-based therapy over a histology-based one, with promising preliminary results.

Drug Repositioning: New Approaches and Future Prospects for Life-Debilitating Diseases and the COVID-19 Pandemic Outbreak

Traditionally, drug discovery utilises a de novo design approach, which requires high cost and many years of drug development before it reaches the market. Novel drug development does not always account for orphan diseases, which have low demand and hence low-profit margins for drug developers. Recently, drug repositioning has gained recognition as an alternative approach that explores new avenues for pre-existing commercially approved or rejected drugs to treat diseases aside from the intended ones. Drug repositioning results in lower overall developmental expenses and risk assessments, as the efficacy and safety of the original drug have already been well accessed and approved by regulatory authorities. The greatest advantage of drug repositioning is that it breathes new life into the novel, rare, orphan, and resistant diseases, such as Cushing's syndrome, HIV infection, and pandemic outbreaks such as COVID-19. Repositioning existing drugs such as Hydroxychloroquine, Remdesivir, Ivermectin and Baricitinib shows good potential for COVID-19 treatment. This can crucially aid in resolving outbreaks in urgent times of need. This review discusses the past success in drug repositioning, the current technological advancement in the field, drug repositioning for personalised medicine and the ongoing research on newly emerging drugs under consideration for the COVID-19 treatment.

Feasibility and first reports of the MATCH-R repeated biopsy trial at Gustave Roussy

Unravelling the biological processes driving tumour resistance is necessary to support the development of innovative treatment strategies. We report the design and feasibility of the MATCH-R prospective trial led by Gustave Roussy with the primary objective of characterizing the molecular mechanisms of resistance to cancer treatments. The primary clinical endpoints consist of analyzing the type and frequency of molecular alterations in resistant tumours and compare these to samples prior to treatment. Patients experiencing disease progression after an initial partial response or stable disease for at least 24 weeks underwent a tumour biopsy guided by CT or ultrasound. Molecular profiling of tumours was performed using whole exome sequencing, RNA sequencing and panel sequencing. At data cut-off for feasibility analysis, out of 333 inclusions, tumour biopsies were obtained in 303 cases (91%). From these biopsies, 278 (83%) had sufficient quality for analysis by high-throughput next generation sequencing (NGS). All 278 samples underwent targeted NGS, 215 (70.9%) RNA sequencing and 222 (73.2%) whole exome sequencing. In total, 163 tumours were implanted in NOD scid gamma (NSG) or nude mice and 54 patient-derived xenograft (PDX) models were established, with a success rate of 33%. Adverse events secondary to invasive tumour sampling occurred in 24 patients (7.6%). Study recruitment is still ongoing. Systematic molecular profiling of tumours and the development of patient-derived models of acquired resistance to targeted agents and immunotherapy is feasible and can drive the selection of the next therapeutic strategy.

Clinical Utility of Reflex Ordered Testing for Molecular Biomarkers in Lung Adenocarcinoma

INTRODUCTION

In order to standardize and expedite molecular biomarker testing, we implemented reflex ordered testing of targeted gene alterations in newly diagnosed lung adenocarcinomas within our hospital system.

PATIENTS AND METHODS

Reflex ordered testing of specific molecular biomarkers at the time of pathologic diagnosis of lung adenocarcinoma was approved and adopted system-wide in our hospital during 2017. Through institutional review board approval, we retrospectively looked at cohort of patients whose specimens received a diagnosis of lung adenocarcinoma, with molecular biomarker testing performed at Houston Methodist Hospital between 2016 and 2018. We compared average turnaround time (TAT) from 2016 (prior to reflex ordered testing) to 2017 and 2018 (post reflex ordered testing).

RESULTS

Standard molecular testing performed on 39 patients in 2016 had an average TAT of 52.6 days, whereas reflex ordered molecular testing in 2017 yielded an average TAT of 26.5 days (n = 127) and 15.6 days in 2018 (n = 54). The average TAT for reporting of molecular results significantly decreased by 37 days (P = .0002) within our hospital system post adoption of reflex ordered testing for lung adenocarcinoma. Reflex ordered testing also resulted in a higher variant detection rate than standard molecular biomarker ordering practices (48.8% vs. 25.6%; P < .05). Overall, the frequencies and types of variants identified among our cohort were similar to previous reports.

CONCLUSIONS

Reflex ordered testing of molecular biomarkers in lung adenocarcinoma led to significantly decreased TAT within our hospital system and higher detection rates of targeted gene alterations.

Oncogene-Addicted Non-Small-Cell Lung Cancer: Treatment Opportunities and Future Perspectives

Before the introduction of tyrosine kinase inhibitors (TKIs) for a particular subgroup of patients, despite platinum-based combination chemotherapy, the majority of patients affected by non-small-cell lung cancer (NSCLC) did not live longer than one year. With deeper understanding of tumor molecular biology, treatment of NSCLC has progressively entered the era of treatment customization according to tumor molecular characteristics, as well as histology. All this information allowed the development of personalized molecular targeted therapies. A series of studies have shown that, in some cases, cancer cells can grow and survive as result of the presence of a single driver genomic abnormality. This phenomenon, called oncogene-addiction, more often occurs in adenocarcinoma histology, in non-smokers (except BRAF mutations, also frequent in smoking patients), young, and female patients. Several different driver mutations have been identified and many studies have clearly shown that upfront TKI monotherapy may improve the overall outcome of these patients. The greater efficacy of these drugs is also associated with a better tolerability and safety than chemotherapy, with fewer side effects and an extremely good compliance to treatment. The most frequent oncogene-addicted disease is represented by those tumors carrying a mutation of the epidermal growth factor receptor (EGFR). The development of first, second and third generation TKIs against EGFR mutations have dramatically changed the prognosis of these patients. Currently, osimertinib (which demonstrated to improve efficacy with a better tolerability in comparison with first-generation TKIs) is considered the best treatment option for patients affected by NSCLC harboring a common EGFR mutation. EML4-ALK-driven disease (which gene re-arrangement occurs in 3-7% of NSCLC), has demonstrated to be significantly targeted by specific TKIs, which have improved outcome in comparison with chemotherapy. To date, alectinib is considered the best treatment option for these patients, with other newer agents upcoming. Other additional driver abnormalities, such as ROS1, BRAF, MET, RET and NTRK, have been identified as a target mirroring peculiar vulnerability to specific agents. Oncogene-addicted disease typically has a low early resistance rate, but late acquired resistance always develops and therefore therapy needs to be changed when progression occurs. In this narrative review, the state of art of scientific literature about targeted therapy options in oncogene-addicted disease is summarized and critically discussed. We also aim to analyze future perspectives to maximize benefits for this subgroup of patients.

Management of Non-small Cell Lung Cancer Patients with MET Exon 14 Skipping Mutations

OPINION STATEMENT

The MET exon 14 skipping mutation is found in approximately 3% of lung adenocarcinomas and slightly more than 2% of lung squamous cell carcinomas. In recent years, more and more evidence has shown that MET inhibitors have achieved good anti-tumor effect in patients with MET exon 14 skipping mutation, suggesting that MET exon 14 skipping mutation may be a new target for NSCLC patients. Patients with positive MET exon 14 skipping mutation are recommended to be administered MET inhibitors, and crizotinib is recommended by the NCCN guideline. Due to the presence of gene amplification, second site mutation, bypass activation, and pathological type transformation, one of the inevitable problems of targeted therapy is drug resistance. If type I MET inhibitors (crizotinib, capmatinib, tepotinib, savolitinib) drug resistance is developed, type II MET inhibitors (cabozantinib, glesatinib, merestinib) can be considered.

Phase II, open-label, multicenter trial of crizotinib in Japanese patients with advanced non-small cell lung cancer harboring a MET gene alteration: Co-MET study

BACKGROUND

MET-deregulated non-small cell lung cancer represents an urgent clinical need because of the lack of specific therapies. Although recent studies have suggested a potential role for crizotinib in patients harboring MET gene alterations, no conclusive data are currently available. Therefore, we designed the Co-MET study, a single-arm phase II study to assess the efficacy and safety of crizotinib in patients with advanced non-small cell lung cancers harboring MET gene alterations.

METHODS

Co-MET is an open-label, multi-center, single-arm, phase II trial to assess the safety and efficacy of oral crizotinib in patients with advanced non-small cell lung cancer harboring MET exon 14 skipping mutation (cohort 1) or a high MET gene copy number of ≥ 7 (cohort 2). We will identify MET gene alterations using RT-PCR and/or next-generation sequencing. Oral crizotinib 250 mg BID will be administered until disease progression or unacceptable toxicity. A radiology committee will review tumor scans according to the RECIST criteria. The primary endpoint is the objective response rate. Assuming a null hypothesis of 20% objective response rate and an alternative hypothesis of 50% objective response rate for cohort 1, and a one-sided alpha error of 0.05 and 80% power based on the exact binomial distribution, the required number of evaluable patients is 19. We set the exploratory sample size for cohort 2 at 10 patients.

DISCUSSION

The results of this study are expected to provide evidence regarding the usefulness of oral crizotinib for advanced MET exon 14 skipping mutation-positive or MET high gene copy number-positive non-small cell lung cancer.

TRIAL REGISTRATION

This study was registered with the University Hospital Medical Information Network Clinical Trials Registry as UMIN000031623 on 3 March 2018.

MET Oncogene in Non-Small Cell Lung Cancer: Mechanism of MET Dysregulation and Agents Targeting the HGF/c-Met Axis

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death worldwide and has a poor prognosis. Current treatments for advanced NSCLC included traditional chemotherapy, radiotherapy, targeted therapy, and immunotherapy. The efficacy of targeted therapy relies on oncogene addiction. Mesenchymal-epithelial transition factor (MET) gene can encode unconventional receptor tyrosine kinases with pleiotropic functions, when signals are abnormally activated, it can initiate and maintain tumor transformation, promote cell proliferation, survival, tumor invasion and angiogenesis. Thus, it is a promising therapeutic target. Previous studies have shown that elevated levels of HGF and/or overexpression of c-Met are associated with poor prognosis in lung cancer. In preclinical and clinical trials, c-MET inhibitors have shown some antitumor activity in NSCLC. Although the efficacy results of MET inhibitors in Phase III clinical trials are disappointing, given the molecular heterogeneity of NSCLC, only subgroups of patients with MET gene alterations may benefit from c-MET inhibitors. The challenge for the future is to screen out the potential beneficiaries. To solve this problem, there is need for large data analysis for the detection methods and treatment effects, to establish standards that meet the MET activation status, and determine reliable thresholds to achieve effective patient stratification and clinical decision making. This article summarized the structure of the hepatocyte growth factor (HGF)/c-Met axis, the different mechanisms of MET addiction, as well as MET amplification as acquired resistance mechanism to epidermal growth factor receptor-tyrosine kinase inhibitors, the latest advances of MET inhibitors, and immuotherapy in the treatment of NSCLC with MET alterations.

Acquired Resistance in Lung Cancer

The last decade has witnessed a transformation in the treatment of advanced-stage lung cancer from a largely palliative approach to one where long-term durable remissions and even cures might be within reach. In this review, we discuss the current state of oncogene-directed precision medicine therapies in lung cancer and focus on the major cause of mortality for lung cancer patients: acquired resistance. We consider the multifaceted resistance mechanisms tumors utilize, often simultaneously. We then present areas for future scientific and clinical investigation with an emphasis on population dynamics, early detection, combinatorial therapies targeting resistance mechanisms, and understanding the drug-tolerant persister state.

Acquisition of Cabozantinib-Sensitive MET D1228N Mutation During Progression on Crizotinib in MET-Amplified Triple-Negative Breast Cancer

BACKGROUND

Targeting of somatic MET mutations using crizotinib has led to strong clinical responses, most frequently in patients with lung cancer, raising the possibility of adopting similar treatment strategies in patients with MET alterations in other cancer types.

PATIENT AND METHODS

We describe a patient with advanced triple-negative breast cancer with a 30-fold amplification of MET. Next-generation sequencing of pre- and postprogression biopsies was performed to identify the resistance mechanism emerging after an initial exceptional response to crizotinib. The response of the resistance mutant to type I and II MET inhibitors was assessed in cultured cells.

RESULTS

After progressing on crizotinib, a MET-D1228N mutation was detected, which is located in the crizotinib-binding region of the MET kinase domain. Experimental studies demonstrated that this mutation confers complete resistance to crizotinib yet retains cabozantinib sensitivity. Treatment of the patient with cabozantinib led to a subjective improvement in clinical symptoms, but the patient progressed after 7 weeks.

CONCLUSION

Although MET mutations are rare in breast cancer, these patients may experience substantial clinical benefit from crizotinib treatment. Nevertheless, drug resistance owing to on-target MET mutations will likely be frequently encountered and comprehensive mechanistic studies to assess sensitivity of these mutants to a series of potential second-line therapies may help guide subsequent treatment for these patients.

Precision medicine and actionable alterations in lung cancer: A single institution experience

OBJECTIVES

Oncology has become more reliant on new testing methods and a greater use of electronic medical records, which provide a plethora of information available to physicians and researchers. However, to take advantage of vital clinical and research data for precision medicine, we must initially make an effort to create an infrastructure for the collection, storage, and utilization of this information with uniquely designed disease-specific registries that could support the collection of a large number of patients.

MATERIALS AND METHODS

In this study, we perform an in-depth analysis of a series of lung adenocarcinoma patients (n = 415) with genomic and clinical data in a recently created thoracic patient registry.

RESULTS

Of the 415 patients with lung adenocarcinoma, 59% (n = 245) were female; the median age was 64 (range, 22-92) years with a median OS of 33.29 months (95% CI, 29.77-39.48). The most common actionable alterations were identified in EGFR (n = 177/415 [42.7%]), ALK (n = 28/377 [7.4%]), and BRAF V600E (n = 7/288 [2.4%]). There was also a discernible difference in survival for 222 patients, who had an actionable alteration, with a median OS of 39.8 months as compared to 193 wild-type patients with a median OS of 26.0 months (P<0.001). We identified an unprecedented number of actionable alterations [53.5% (222/415)], including distinct individual alteration rates, as compared with 15.0% and 22.3% in TCGA and GENIE respectively.

CONCLUSION

The use of patient registries, focused genomic panels and the appropriate use of clinical guidelines in community and academic settings may influence cohort selection for clinical trials and improve survival outcomes.

First-in-human phase I study of BPI-9016M, a dual MET/Axl inhibitor, in patients with non-small cell lung cancer

Background

BPI-9016M is a novel small-molecule inhibitor that simultaneously targets both c-Met and AXL tyrosine kinases. This phase I study aimed to determine the maximum tolerated dose (MTD), safety, pharmacokinetics, and antitumor activity of BPI-9016M in Chinese patients with advanced non-small cell lung cancer (NSCLC).

Methods

Over the dose range of 100 mg to 800 mg, eligible patients were administered with a single dose of 9016M tablet and received 7 days of pharmacokinetics evaluation, followed by continuous dose administration (QD dosing, 28 days). Standard “3 + 3” dose escalations were performed.

Results

Twenty NSCLC patients were treated. All patients experienced at least one adverse event (AE), of which treatment-related adverse events (TRAEs) were reported in 17 (85.0%) patients. The most common TRAEs were alanine transaminase (ALT) elevation (60%), bilirubin increased (40%), dysgeusia (40%), constipation (30%), hypertension (25%), and palmar-plantar erythrodysesthesia syndrome (15%). The TRAEs of grade 3 or higher during treatment were hypertension (15%), pulmonary embolism (5%), and laryngeal pain (5%). No dose-limiting toxicity (DLT) was observed, and the MTD was not reached. The median time to C_max ranged from 2.0 to 3.5 h, and the plasma concentration of BPI-9016M declined rapidly after T_max fitting a single-compartment model. The mean AUC_0–72 h of M1 and M2-2, main metabolites of BPI-9016M, were 4.8–6.6 folds and 4.1–9.8 folds higher than that of BPI-9016M, respectively. Exposure to BPI-9016M, M1, and M2-2 reached moderate saturation at 600 mg. Among 19 evaluable patients, 1 had a partial response and 10 patients had stable disease.

Conclusion

BPI-9016M showed favorable safety and pharmacokinetic profiles, and no DLT was observed at doses up to 800 mg once daily. The promising antitumor activity in Chinese NSCLC patients supports further development of this tyrosine kinase inhibitor.

Trial registration

Clinical Trial ID: NCT02478866, registered May 21, 2015.

Elucidation of the relationships of MET protein expression and gene copy number status with PD-L1 expression and the immune microenvironment in non-small cell lung cancer

OBJECTIVES

Alterations in the MET gene, such as mutations and high-level amplification, are important drivers of non-small cell lung cancer (NSCLC). The efficacy of immune checkpoint inhibitors (ICIs) in lung cancer with MET abnormalities is unclear. We evaluate the potential relationship between MET alterations and the tumor immune microenvironment and PD-1/PD-L1 axis.

MATERIAL AND METHODS

MET and phospho-MET protein expression were assessed in 622 resected NSCLC specimens. MET amplification was assessed by fluorescence in-situ hybridization in 272 tumors. PD-L1 expression was evaluated by immunohistochemistry. CD8+, Foxp3+, CD45RO, and PD-1+ tumor-infiltrating lymphocytes (TILs) in the tumor nest and surrounding stroma were profiled. Associations with MET alterations were explored.

RESULTS

The cohort comprised 425 male patients (68.3 %), 184 never-smokers (29.6 %), and 408 adenocarcinoma (ADC) patients (65.6 %). Median age was 68 years. MET alteration was observed mainly in ADCs (18.9 % MET-positive, 3.9 % phospho-MET-positive, and 15.1 % with MET amplification). PD-L1 expression was significantly increased in MET-altered ADCs (P < 0.001 for MET; P = 0.002 for phospho-MET; P = 0.019 for MET amplification). Most TIL subset numbers in the tumor nest were significantly increased in MET-altered tumors. Only MET amplification was independently associated with tumoral CD8 + TILs. Three of the six patients responded to ICI treatment; two of them showed MET overexpression and an increase in MET copy number.

CONCLUSION

MET-altered tumors showed significantly stronger PD-L1 expression and more abundant tumoral TILs than non-MET-altered tumors. Among the MET alterations assessed, MET amplification was particularly implicated in the inflamed microenvironment, suggesting that MET-amplified tumors might respond to ICIs.

Antitumor activity of crizotinib in lung cancers harboring a MET exon 14 alteration

MET exon 14 alterations are oncogenic drivers of non-small-cell lung cancers (NSCLCs)1. These alterations are associated with increased MET activity and preclinical sensitivity to MET inhibition2. Crizotinib is a multikinase inhibitor with potent activity against MET3. The antitumor activity and safety of crizotinib were assessed in 69 patients with advanced NSCLCs harboring MET exon 14 alterations. Objective response rate was 32% (95% confidence interval (CI), 21-45) among 65 response-evaluable patients. Objective responses were observed independent of the molecular heterogeneity that characterizes these cancers and did not vary by splice-site region and mutation type of the MET exon 14 alteration, concurrent increased MET copy number or the detection of a MET exon 14 alteration in circulating tumor DNA. The median duration of response was 9.1 months (95% CI, 6.4-12.7). The median progression-free survival was 7.3 months (95% CI, 5.4-9.1). MET exon 14 alteration defines a molecular subgroup of NSCLCs for which MET inhibition with crizotinib is active. These results address an unmet need for targeted therapy in people with lung cancers with MET exon 14 alterations and adds to an expanding list of genomically driven therapies for oncogenic subsets of NSCLC.

Phase 1 study of capmatinib in MET-positive solid tumor patients: Dose escalation and expansion of selected cohorts

Capmatinib is an oral, ATP‐competitive, and highly potent, type 1b MET inhibitor. Herein, we report phase 1 dose‐escalation results for capmatinib in advanced MET‐positive solid tumor patients and dose expansion in advanced non‐lung tumors. Capmatinib was well tolerated with a manageable safety profile across all explored doses. Dose‐limiting toxicities (DLT) occurred at 200 mg twice daily (bid), 250 mg bid, and 450 mg bid capsules; however, no DLT were reported at 600 mg bid (capsules). Capmatinib tablets at 400 mg bid had comparable tolerability and exposure to that of 600 mg bid capsules. Maximum tolerated dose was not reached; recommended phase 2 dose was 400 mg bid tablets/600 mg bid capsules; at this dose, C_trough >EC₉₀ (90% inhibition of c‐MET phosphorylation in animal models) is expected to be achieved and maintained. Among the dose‐expansion patients (N = 38), best overall response across all cohorts was stable disease (gastric cancer 22%, hepatocellular carcinoma 46%, other indications 28%); two other indication patients with gene copy number (GCN) ≥6 achieved substantial tumor reduction. Near‐complete immunohistochemically determined phospho‐MET inhibition (H‐score = 2) was shown following capmatinib 450 mg bid capsule in paired biopsies obtained from one advanced colorectal cancer patient. Incidence of high‐level MET GCN (GCN ≥6) and MET‐overexpressing (immunohistochemistry 3+) tumors in the expansion cohorts was 8% and 13%, respectively; no MET mutations were observed. Thus, the recommended phase 2 dose (RP2D) of capmatinib was 600 mg bid capsule/400 mg bid tablet. Capmatinib was well tolerated and showed antitumor activity and acceptable safety profile at the RP2D.

(ClinicalTrials.gov Identifier: NCT01324479).

Dose-escalation trial of the ALK, MET & ROS1 inhibitor, crizotinib, in patients with advanced cancer

Aim: This first-in-human, dose-finding study evaluated safety, pharmacokinetics and pharmacodynamics of crizotinib and established a recommended Phase II dose (RP2D) among patients with advanced solid malignancies. Patients & methods: Patients received oral crizotinib in a 3 + 3 dose escalation design. Results: Thirty-six patients received crizotinib (50 mg once daily-300 mg twice daily); maximum tolerated dose (and RP2D) was 250 mg twice daily. Most patients (89%) experienced ≥1 treatment-related adverse event. Three patients had grade 3 dose-limiting toxicities: alanine aminotransferase increased (n = 1) and fatigue (n = 2). Generally, an increase in soluble MET was found with increasing crizotinib concentrations. Conclusion: Crizotinib demonstrated a favorable safety profile. The observed pharmacodynamic effect on soluble MET provide evidence for targeted MET inhibition by crizotinib. Clinicaltrials. gov identifier: NCT00585195.

Highly accurate DNA-based detection and treatment results of MET exon 14 skipping mutations in lung cancer

OBJECTIVES

The oncogenic MET exon 14 skipping mutation (METex14del) is described to drive 1.3 %-5.7 % of non-small-cell lung cancer (NSCLC) and multiple studies with cMET inhibitors show promising clinical responses. RNA-based analysis seems most optimal for METex14del detection, however, acquiring sufficient RNA material is often problematic. An alternative is DNA-based analysis, but commercially available DNA-based panels only detect up to 63 % of known METex14del alterations. The goal of this study is to describe an optimized DNA-based diagnostic test for METex14del in NSCLC, including clinical features and follow-up of patients treated with cMET-targeted therapy and consequent resistance mechanisms.

MATERIAL AND METHODS

Routinely processed diagnostic pathology non-squamous NSCLC specimens were investigated by a custom-made DNA-based targeted amplicon-based next generation sequencing (NGS) panel, which includes 4 amplicons for METex14del detection. Retrospectively, histopathological characteristics and clinical follow up were investigated for advanced non-squamous NSCLC with METex14del.

RESULTS

In silico analysis showed that our NGS panel is able to detect 96 % of reported METex14 alterations. METex14del was found in 2 % of patients with non-squamous NSCLC tested for therapeutic purposes. In total, from May 2015 - Sep 2018, METex14del was found in 46 patients. Thirty-six of these patients had advanced non-squamous NSCLC, they were predominantly elderly (76.5 years [53-90]), male (25/36) and (ex)-smokers (23/36). Five patients received treatment with crizotinib (Pfizer Oncology), in a named patient based program, disease control was achieved for 4/5 patients (3 partial responses, 1 stable disease) and one patient had a mixed response. Two patients developed a MET D1228N mutation during crizotinib treatment, inducing a resistance mechanism to crizotinib.

CONCLUSIONS

This study shows that METex14del can be reliably detected by routine DNA NGS analysis. Although a small cohort, patients responded well to targeted treatment, underlining the need for routine testing of METex14del in advanced non-squamous NSCLC to guarantee optimal personalized treatment.

MET Genomic Alterations in Head and Neck Squamous Cell Carcinoma (HNSCC): Rapid Response to Crizotinib in a Patient with HNSCC with a Novel MET R1004G Mutation

Identification of effective targeted therapies for recurrent/metastatic head and neck squamous cell carcinoma (HNSCC) remains an unmet medical need. A patient with platinum-refractory recurrent oral cavity HNSCC underwent comprehensive genomic profiling (CGP) that identified an activating MET mutation (R1004). The patient was treated with the oral MET tyrosine kinase inhibitor crizotinib with rapid response to treatment.Based on this index case, we determined the frequency of MET alterations in 1,637 HNSCC samples, which had been analyzed with hybrid capture-based CGP performed in the routine course of clinical care. The specimens were sequenced to a median depth of >500× for all coding exons from 182 (version 1, n = 24), 236 (version 2, n = 326), or 315 (version 3, n = 1,287) cancer-related genes, plus select introns from 14 (version 1), 19 (version 2), or 28 (version 3) genes frequently rearranged in cancer. We identified 13 HNSCC cases (0.79%) with MET alterations (4 point mutation events and 9 focal amplification events). MET-mutant or amplified tumors represent a small but potentially actionable molecular subset of HNSCC. KEY POINTS: This case report is believed to be the first reported pan-cancer case of a patient harboring a MET mutation at R1004 demonstrating a clinical response to crizotinib, in addition to the first documented case of head and neck squamous cell carcinoma (HNSCC) with any MET alteration responding to crizotinib.The positive response to MET inhibition in this patient highlights the significance of comprehensive genomic profiling in advanced metastatic HNSCC to identify actionable targetable molecular alterations as current treatment options are limited.

MET Inhibition in Non-Small Cell Lung Cancer

Cancer treatment paradigms have evolved over recent years with an emphasis on personalised medicine. Targeted agents are being used to improve treatment outcomes and quality of life. For the treatment of non-small cell lung cancer, several agents with unique genetic and epigenetic targets are available. To this extent, mesenchymal–epithelial transition (MET), a heterodimer receptor tyrosine kinase involved in embryogenesis and organogenesis, has been investigated as a potential target for biological agents. MET dysregulation can occur via different mechanisms and trigger tumourigenesis and disease spread. Besides driving the oncogenic dependence of cells, MET is also involved in acquired resistance to epidermal growth factor receptor inhibitors. As such, many small molecule kinase inhibitors and antibodies have been developed or are currently in different phases of clinical trials to counteract the MET-induced neoplastic activity. Some of these agents are selective while others are nonselective with multiple other potential targets. This article aims to present an overview of biological functioning of MET, its role in oncogenesis and resistance to treatment, and clinical studies evaluating MET inhibitors for treatment of non-small cell lung cancer.

Phase I dose-escalation study of capmatinib (INC280) in Japanese patients with advanced solid tumors

Capmatinib is a highly specific, potent and selective MET inhibitor. This was an open‐label, multicenter, dose‐escalation, phase I study conducted in Japanese patients with advanced solid tumors (not selected based on their MET status). The primary objective was to determine the maximum tolerated dose (MTD) and/or highest studied dose being safe. Secondary objectives included safety, pharmacokinetics and preliminary antitumor activity. Dose escalation was guided by a Bayesian Logistic Regression Model dependent on dose‐limiting toxicities (DLT) in cycle 1. Of 44 adult Japanese patients with confirmed advanced solid tumors enrolled, 29 received capmatinib capsules (doses ranging from 100 mg once daily [q.d.] to 600 mg twice daily [b.i.d.]) and 15 received tablets (200 mg b.i.d. and 400 mg b.i.d.). DLT occurred in two patients: grade 2 suicidal ideation (600 mg b.i.d. capsule) and grade 3 depression (400 mg b.i.d. tablet). MTD was not reached. The highest studied dose determined to be safe as tablet was 400 mg b.i.d., whereas it is not yet determined for capsules. Most common adverse events suspected to be drug‐related were increased blood creatinine, nausea, decreased appetite, vomiting and diarrhea. Following repeated daily dosing up to day 15 by q.d. or b.i.d. regimen using capsules, median time to reach maximum plasma drug concentration (T_max) was 1.0‐4.0 hours; absorption was more rapid after dosing using tablets, with median T_max of 1.0 hour on both days 1 and 15. Eight patients had a best overall response of stable disease. These data support further clinical development of capmatinib.

Case report: HER2 amplification as a resistance mechanism to crizotinib in NSCLC with MET exon 14 skipping

Patients with non-small cell lung cancer (NSCLC) harboring MET exon 14 skipping can benefit from crizotinib treatment. Currently, the main resistance mechanisms to crizotinib are MET D1228N and Y1230C mutations. We reported a case of a Chinese NSCLC patient with MET exon 14 skipping detected by targeted next-generation sequencing (NGS) achieved clinical and imaging remission after crizotinib treatment. Then, amplification of multiple genes such as erb-b2 receptor tyrosine kinase 2 (HER2) was detected when disease progressed, indicating novel resistance mechanisms to crizotinib. Ultimately the patient died from cancer-related factors. This was the first NSCLC case with MET exon 14 skipping which reported the HER2 gene amplification at the time of progression during crizotinib treatment, indicating that bypass mechanisms contribute to the development of acquired resistance to MET inhibitors.