Circulating tumour DNA biomarkers in savolitinib-treated patients with non-small cell lung cancer harbouring MET exon 14 skipping alterations: a post hoc analysis of a pivotal phase 2 study

Ensartinib for advanced or metastatic non-small-cell lung cancer with MET exon 14 skipping mutations (EMBRACE): a multi-center, single-arm, phase 2 trial

Background

MET exon14 skipping mutations (METex14) is an established actionable driver oncogene of non-small-cell lung cancer (NSCLC). While ensartinib is a known second-generation tyrosine kinase inhibitor with primary activity against ALK translocation, it is also classified as a type Ia MET inhibitor. We have previously shown anti-tumor activity against METex14 positive NSCLC both in vivo and in vitro. The EMBRACE trial aims to evaluate the clinical efficacy and safety of ensartinib for treatment of METex14 positive NSCLC.

Methods

This is a multicenter single arm phase II investigator-initiated study that enrolled METex14 positive lung cancer after failing first line chemotherapy and/or immunotherapy. Eligible patients received ensartinib 225 mg orally once daily in a continuous 28-day treatment cycle until disease progression, unacceptable side effect, or death. Primary endpoint was investigator-assessed objective response rate (ORR), and the secondary end point included disease control rate (DCR), progression-free survival (PFS), duration of response (DoR) and safety profiles. The study was registered with the Chinese Clinical Trial Registry (ChiCTR2100048767).

Findings

From July 2021 to February 2024, a total of 31 patients were enrolled and received ensartinib. Median follow-up time of the 30 evaluable patients was 9.2 months (95% Confidence Interval [CI], 6.3-not estimable). The ORR was 53.3% (16/30; 95% CI, 35.5-71.2) and DCR was 86.7% (26/30; 95% CI, 74.5-98.8). Median PFS was 6.0 months (95% CI, 3.0-8.8) and median DoR was 7.9 months (95% CI, 4.8-8.7). Adverse events (AEs) were reported in 24 patients (80%), with 7 (23.3%) of grade 3. The most common AEs were rash (14/30, 46.7%), followed by anemia (7/30, 23.3%), increased ALT (7/30, 23.3%), increased AST (7/30, 23.3%), and pruritus (6/30, 20%). No serious adverse events or treatment-related deaths occurred. Importantly, the exploratory ctDNA analysis indicates that clearance of circulating tumor DNA (ctDNA) at four weeks treatment was associated with more favorable treatment outcomes comparing with patients having positive ctDNA.

Interpretation

Ensartinib has a promising anti-tumor activity and manageable safety in previously treated patients with METex14 positive lung cancer.

Funding

This work was supported by the National Natural Science Foundation of China [82370028, 82422001] and the CSCO-MET Aberrant Solid Tumor Research Grant [Y-2022METAZMS-0066].

Savolitinib in patients in China with locally advanced or metastatic treatment-naive non-small-cell lung cancer harbouring MET exon 14 skipping mutations: results from a single-arm, multicohort, multicentre, open-label, phase 3b confirmatory study

BACKGROUND

Savolitinib has been approved in China for advanced or metastatic non-small-cell lung cancer (NSCLC) with MET exon 14 (METex14) skipping alterations in previously treated patients and those unable to receive platinum-based chemotherapy. We report results from a treatment-naive cohort of a phase 3b study that was designed to evaluate the efficacy and safety of savolitinib in locally advanced or metastatic METex14-mutated NSCLC.

METHODS

This single-arm, multicohort, multicentre, open-label, phase 3b study was done at 48 hospitals in China in adult (≥18 years) patients with locally advanced or metastatic METex14-mutated NSCLC who had not received previous systemic antitumour therapy. Patients with a bodyweight of 50 kg or more and those with a bodyweight of less than 50 kg received savolitinib once daily at 600 mg or 400 mg, respectively, in 21-day cycles. The primary endpoint was objective response rate assessed by independent review committee (IRC) per Response Evaluation Criteria in Solid Tumours, version 1.1. The full analysis set comprised all patients who received at least one dose of study medication, which was used to assess the efficacy endpoints and baseline and safety data. This study is registered with ClinicalTrials.gov (NCT04923945) and is closed to accrual.

FINDINGS

Between Aug 31, 2021, and Oct 20, 2023, 125 treatment-naive patients were assessed for eligibility, of whom 87 were enrolled and received savolitinib. The median age of patients was 70·0 years (IQR 65·2-75·8) and 51 (59%) of 87 patients were male and 36 (41%) were female. In the full analysis set, the IRC-assessed objective response rate was 62% (95% CI 51-72) and the investigator-assessed objective response rate was 60% (49-70), showing a high concordance rate (84%). Treatment-related adverse events were reported in 85 (98%) of 87 patients, with peripheral oedema (54 [62%]) being the most common. Two of these treatment-related adverse events led to death (cardiac failure n=1, unknown reasons n=1).

INTERPRETATION

Savolitinib showed manageable toxicity and promising efficacy in treatment-naive patients with advanced or metastatic METex14-mutated NSCLC.

FUNDING

HUTCHMED and AstraZeneca.

Molecular profiling METex14+ non-small cell lung cancer (NSCLC): Impact of histology

OBJECTIVES

MET exon 14 skipping alterations (METex14+) represent a heterogeneous subgroup of non-small cell lung cancer (NSCLC) with distinct biological and genomic features. We characterized this heterogeneity in a large cohort, integrating genomic and transcriptomic profiling with clinical outcomes, to elucidate the histologic and molecular traits and survival patterns of METex14+ NSCLC.

MATERIALS AND METHODS

NSCLC tissue samples (n = 28,739) underwent DNA-based next-generation sequencing (592 genes, NextSeq) or whole-exome sequencing (NovaSeq), RNA-sequencing including whole transcriptome sequencing (WTS, NovaSeq), and PD-L1 IHC (Dako 22C3) at Caris Life Sciences. Immune cell fractions were estimated from bulk RNA sequencing (quanTIseq). Real-world survival data (mOS) was calculated from insurance claims. Statistical analyses employed Chi-square, Fisher's exact, or Mann-Whitney U and log-rank tests and were corrected for hypothesis testing where applicable.

RESULTS

A total of 711 METex14+ cases were detected. Of 575 cases of defined histology, 77 (13.6 %) were squamous (Sq), 474 (82.3 %) were nSq (non-squamous), and 24 (4.1 %) were adenosquamous. Mutations in POT1 and BRCA2 were enriched, and amplifications in MDM2, HMGA2, CDK4, and MET were common in METex14+ tumors. TMB-high and TP53 mutated tumors were reduced in METex14+ independent of histology. KEAP1 (2.1 vs 14.7 %) and STK11 mutations (0.8 vs 17.1 %) were reduced only in METex14+ nSq (vs METex14+ Sq, q < 0.05). While the prevalence of PD-L1 high tumors was enriched in METex14+ independent of histology, T-cell inflamed tumors were enriched only in nSq METex14+. B-cells and CD8+ T-cells (1.07-1.43-fold) were enriched in nSq METex14+, and dendritic cells (0.32 fold) were reduced only in METex14+ Sq. METex14+ tumors had a modest improvement in mOS compared to METex14- tumors (mOS = 22.9 m vs 18.6 m, HR = 0.914, p = 0.04). Moreover, METex14+ tumors who received immunotherapy (IO) had a modest improvement in survival (mOS = 27.5 m vs 21.8 m; HR = 0.803, p = 0.03) compared to those who did not receive IO. METex14+ nSq tumors were associated with improved mOS compared to METex14+ Sq tumors (mOS = 27.7 vs 8.9 m, HR = 0.493, p < 0.0001).

CONCLUSION

METex14+ alterations are a heterogeneous subgroup of NSCLC. Our analysis reveals that METex14+ nSq exhibit improved survival compared to METex14+ Sq. The distinct genomic and transcriptomic variations across histologies warrant clinical consideration.

Savolitinib conferred sensitivity in a patient with D1228H mutation-induced capmatinib-resistant MET exon 14 skipping mutated lung adenocarcinoma

Traditionally, the D1228 E/G/H/N mutation has been thought to cause Type I MET-TKI resistance. We reported a 75-year-old female with non-small cell lung cancer harboring MET exon 14 skipping mutation, who developed acquired MET D1228H mutation induced by capmatinib treatment. Interestingly, the patient demonstrated marked response to second-line savolitinib treatment with the duration of response of 19 months and several additional metastatic lesions appeared. Pathological assessment of rebiopsy sample showed adenocarcinoma and targeted next-generation sequencing revealed the loss of MET D1228H mutation and presence of MET p.Y1230N mutation. In response, the treatment regimen was amended to include a daily administration of 60 mg of cabozantinib, which resulted in moderate size reduction of the tumours. The switch of resistance mutations indicated that different type Ib MET inhibitors may exhibit distinct mechanisms of resistance. We call for futher studies on resistance based on patient-derived pre-clinical models including patient-derived tumor-like cell clusters, patient-derived organoids, and patient-derived xenografts.

Plasma ddPCR for the detection of MET amplification in advanced NSCLC patients: a comparative real-world study

Background

Mesenchymal-epithelial transition (MET) amplification is a crucial oncogenic driver and a resistance mechanism to epidermal growth factor receptor tyrosine kinase inhibitors (TKIs) of non-small-cell lung cancer (NSCLC). Fluorescence in situ hybridization (FISH) is the gold standard for MET amplification detection. However, it is inapplicable when tissue samples are unavailable.

Objective

This study assessed the performance of plasma droplet digital polymerase chain reaction (ddPCR) in MET amplification detection in NSCLC patients.

Design and methods

A total of 87 NSCLC patients were enrolled, and 94 paired tissue and plasma samples were analyzed for the concordance between FISH and plasma ddPCR/tissue next-generation sequencing (NGS) in detecting MET amplification. In addition, the efficacy of patients with MET amplification using different detection methods who were treated with MET-TKIs was evaluated.

Results

Plasma ddPCR showed substantial concordance with FISH (74.1% sensitivity, 92.5% specificity, and 87.2% accuracy with a kappa value of 0.68) and outperformed tissue NGS (kappa value of 0.64) in MET amplification detection. Combined plasma ddPCR and tissue NGS showed substantial concordance with FISH (92.3% sensitivity, 89.2% specificity, and an accuracy of 90.1% with a kappa value of 0.77). The efficacy is comparable in these NSCLC patients with MET amplification detected by FISH and plasma ddPCR who were treated with MET-TKIs.

Conclusion

Plasma ddPCR is a potentially reliable method for detecting MET amplification in advanced NSCLC patients. Combined plasma ddPCR and tissue NGS might be an alternative or complementary method to MET amplification detection.

Savolitinib: A Promising Targeting Agent for Cancer

Savolitinib is a highly selective small molecule inhibitor of the mesenchymal epithelial transition factor (MET) tyrosine kinase, primarily developed for the treatment of non-small cell lung cancer (NSCLC) with MET mutations. It is also being investigated as a treatment for breast, head and neck, colorectal, gastric, pancreatic, and other gastrointestinal cancers. In both preclinical and clinical studies, it has demonstrated efficacy in lung, kidney, and stomach cancers. Savolitinib is an oral anti-cancer medication taken as a 600 mg dose once daily. It can be used as a monotherapy in patients with non-small cell lung cancer with MET mutations and in combination with epidermal growth factor receptor (EGFR) inhibitors for patients who have developed resistance to them. Furthermore, savolitinib has shown positive results in gastric cancer treatment, particularly in combination with docetaxel. As a result, this review aims to validate its efficacy in NSCLC and suggests its potential application in other gastrointestinal cancers, such as pancreatic cancer, based on related research in gastric and renal cancer.

Clinical application of liquid biopsy based on circulating tumor DNA in non-small cell lung cancer

Lung cancer is a widely occurring and deadly malignancy, with high prevalence rates in China and across the globe. Specifically, non-small cell lung cancer (NSCLC) represents about 85% of all lung cancer cases. The 5-year disease-free survival rate after surgery for stage IB-IIIB NSCLC patients (disease-free survival, DFS) has notably declined from 73% to 13%. Early detection of abnormal cancer molecules and subsequent personalized treatment plans are the most effective ways to address this problem. Liquid biopsy, surprisingly, enables safe, accurate, non-invasive, and dynamic tracking of disease progression. Among the various modalities, circulating tumor DNA (ctDNA) is the most commonly used liquid biopsy modality. ctDNA serves as a credible "liquid biopsy" diagnostic tool that, to a certain extent, overcomes tumor heterogeneity and harbors genetic mutations in malignancies, thereby providing early information on tumor genetic alterations. Despite considerable academic interest in the clinical significance of ctDNA, consensus on its utility remains lacking. In this review, we assess the role of ctDNA testing in the diagnosis and management of NSCLC as a reference for clinical intervention in this disease. Lastly, we examine future directions to optimize ctDNA for personalized therapy.

Landscape of Savolitinib Development for the Treatment of Non-Small Cell Lung Cancer with MET Alteration-A Narrative Review

Non-small cell lung cancer (NSCLC) is increasingly being treated with targeted therapies. Savolitinib (Orpathys^®) is highly selective mesenchymal epithelial transition (MET)-tyrosine kinase inhibitor (TKI), which is conditionally approved in China for advanced NSCLC with MET exon 14 skipping mutations (METex14). This article summarizes the clinical development of savolitinib, as a monotherapy in NSCLC with METex14 mutation and in combination with epidermal growth factor receptor (EGFR) inhibitor in post EGFR-TKI resistance NSCLC due to MET-based acquired resistance. Preclinical models demonstrated anti-tumor activities in MET-driven cancer cell line and xenograft tumor models. The Phase Ia/Ib study established an optimized, recommended phase II dose in Chinese NSCLC patients, while TATTON study of savolitinib plus osimertinib in patients with EGFR mutant, MET-amplified and TKI-progressed NSCLC showed beneficial efficacy with acceptable safety profile. In a pivotal phase II study, Chinese patients with pulmonary sarcomatoid carcinoma, brain metastasis and other NSCLC subtype positive for METex14 mutation showed notable responses and acceptable safety profile with savolitinib. Currently, results from ongoing clinical trials are eagerly anticipated to confirm the efficacious and safety benefits of savolitinib as monotherapy and in combination with EGFR-TKI in acquired resistance setting in advanced NSCLC and its subtypes with MET alterations.