Epidermal Growth Factor Receptor Tyrosine Research Articles

Identification of potential edible spices as EGFR and EGFR mutant T790M/L858R inhibitors by structure-based virtual screening and molecular dynamics

Epidermal growth factor receptor (EGFR) tyrosine kinases are overexpressed in several human cancers and could serve as a promising anti-cancer drug target. With this in view, the main aim of the present study was to identify spices having the potential to inhibit EGFR tyrosine kinase. The structure-based virtual screening of spice database consisting of 1439 compounds with EGFR tyrosine kinase (PDB ID: 3W32) was carried out using Glide. Top scored 18 hits (XP Glide Score ≥ −10.0 kcal/mol) was further docked with three EGFR tyrosine kinases and three EGFR T790M/L858R mutants using AutodockVina, followed by ADME filtration. The best three hits were further refined by Molecular Dynamics (MD) simulation and MM-GBSA-based binding energy calculation. The overall docking results of the selected hits with both EGFR and EGFR T790M/L858R were quite satisfactory and showed strong binding compared to the three coligands. Detailed MD analysis of CL_07, AC_11 and AS_49 also showed the stability of the protein-ligand complexes. Moreover, the hits were drug-like, and MM-GBSA binding free energy of CL_07 and AS_49 was established to be far better. AC_11 was found to be similar to the known inhibitor Gefitinib. Most of the potential hits are available in Allium cepa, CL_07 and AS_49 available in Curcuma longa and Allium sativum, respectively. Therefore, these three spices could be used as a potential therapeutic candidate against cancer caused by overexpression of EGFR after validation of the observations of this study in in-vitro experiments. Further extensive work is needed to improve the scaffolds CL_07, AC_11, AC_17, and AS_49 as potential anti-cancer drugs. Communicated by Ramaswamy H. Sarma

Characterization of stemness features and construction of a stemness subtype classifier to predict survival and treatment responses in lung squamous cell carcinoma

BackgroundCancer stemness has been proven to affect tumorigenesis, metastasis, and drug resistance in various cancers, including lung squamous cell carcinoma (LUSC). We intended to develop a clinically applicable stemness subtype classifier that could assist physicians in predicting patient prognosis and treatment response.MethodsThis study collected RNA-seq data from TCGA and GEO databases to calculate transcriptional stemness indices (mRNAsi) using the one-class logistic regression machine learning algorithm. Unsupervised consensus clustering was conducted to identify a stemness-based classification. Immune infiltration analysis (ESTIMATE and ssGSEA algorithms) methods were used to investigate the immune infiltration status of different subtypes. Tumor Immune Dysfunction and Exclusion (TIDE) and Immunophenotype Score (IPS) were used to evaluate the immunotherapy response. The pRRophetic algorithm was used to estimate the efficiency of chemotherapeutic and targeted agents. Two machine learning algorithms (LASSO and RF) and multivariate logistic regression analysis were performed to construct a novel stemness-related classifier.ResultsWe observed that patients in the high-mRNAsi group had a better prognosis than those in the low-mRNAsi group. Next, we identified 190 stemness-related differentially expressed genes (DEGs) that could categorize LUSC patients into two stemness subtypes. Patients in the stemness subtype B group with higher mRNAsi scores exhibited better overall survival (OS) than those in the stemness subtype A group. Immunotherapy prediction demonstrated that stemness subtype A has a better response to immune checkpoint inhibitors (ICIs). Furthermore, the drug response prediction indicated that stemness subtype A had a better response to chemotherapy but was more resistant to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). Finally, we constructed a nine-gene-based classifier to predict patients’ stemness subtype and validated it in independent GEO validation sets. The expression levels of these genes were also validated in clinical tumor specimens.ConclusionThe stemness-related classifier could serve as a potential prognostic and treatment predictor and assist physicians in selecting effective treatment strategies for patients with LUSC in clinical practice.

Pemetrexed induces ROS generation and cellular senescence by attenuating TS-mediated thymidylate metabolism to reverse gefitinib resistance in NSCLC.

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKI) are strongly recommended for non-small-cell lung cancer (NSCLC) patients harbouring active EGFR mutations, while drug resistance makes exploring resistance mechanisms and seeking effective therapeutic strategies urgent endeavours. Thymidylate synthetase (TYMS or TS) is a dominant enzyme in thymidylate nucleotide metabolism. In this study, we found a positive correlation between TS expression and overall survival (OS) and disease-free survival (DFS) in lung adenocarcinoma. The examination of gene sets from 140 NSCLC patients received EGFR-TKI therapy demonstrated a negative correlation between high TS expression and the efficacy of EGFR-TKI therapy. 24 tissue specimens from NSCLC patients exhibited upregulated TS mRNA expression in NSCLC patients resistant to gefitinib. The NSCLC cell PC9 and HCC827 sensitive to gefitinib and relatively resistant PC9/GR and HCC827/GR cells were used to demonstrate the knockdown of TS restored the sensitivity of resistant cells to gefitinib. Furthermore, pemetrexed effectively suppressed TS-mediated thymidylate metabolism and induced ROS generation, DNA damage and cellular senescence, thereby hampering cancer progression and restoring sensitivity to gefitinib. Our findings illuminate the potential mechanism of TS-triggered gefitinib resistance and indicate inhibition of TS by pemetrexed can potentiate the effect of gefitinib in NSCLC. Pemetrexed combined with gefitinib has potent anti-progression potential in gefitinib-resistant NSCLC. This study suggests that NSCLC patients with both high TS expression and EGFR-driving mutations might benefit more from a combination strategy of EGFR-TKI and pemetrexed-based chemotherapy than EGFR-TKI monotherapy, which has profound clinical implications and therapeutic value.

Clinical features and prognosis of lung cancer in patients with connective tissue diseases: a retrospective cohort study.

Studies have demonstrated a close association between connective tissue diseases (CTDs) and lung cancer (LC). Evidence supports that poor survival may be associated with the presence of CTDs in patients with LC. This retrospective cohort study investigated 29 patients with LC with CTDs, and 116 patients with LC without CTDs were enrolled as case-matched control cohorts. Medical records, therapeutic efficacy of cancer, and outcomes were analyzed. The median duration from the diagnosis of CTDs to LC was 17 years. The Eastern Cooperative Oncology Group (ECOG) performance score for LC-CTD patients was worse than that for matched non-CTD LC patients. The median progression-free survival (mPFS) and overall survival (mOS) of first-line chemotherapy did not differ between patients with lung adenocarcinoma (AC) with and without CTDs. A significant difference was observed in mPFS [4 months vs. 17 months; hazard ratio (HR), 9.987; p = 0.004] and mOS (6 months vs. 35 months; HR, 26.009; p < 0.001) of first-line epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) treatment between patients with AC with and without CTDs. The presence of CTD, sex, ECOG performance status, and tumor-node-metastasis clinical stage were the independent prognostic factors in all patients with non-small cell LC (NSCLC). ECOG performance status was determined to be an independent prognostic factor in patients with LC-CTD. In patients with NSCLC with CTD (n = 26), sex (male) and worse ECOG score were the independent poor prognostic factors. CTDs were associated with poor survival in patients with LC. The therapeutic efficacy of first-line EGFR-TKI therapy was significantly worse in patients with lung AC with CTDs than in those without CTDs. ECOG performance status was determined as an independent prognostic factor for patients with LC and CTDs.

Alternating Therapy With Osimertinib and Afatinib Blockades EGFR Secondary Mutation in EGFR-Mutant Lung Cancer: A Single-Arm Phase II Trial

BackgroundResistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) has limited treatment options for patients with EGFR-mutated non–small-cell lung cancer (NSCLC). Although osimertinib or afatinib alone induced drug-resistant clones with EGFR secondary mutation in a preclinical model, its combination prevented the appearance of these mutations. We investigated alternating-dose therapy of osimertinib and afatinib in patients with EGFR-mutant NSCLC in a single-arm Phase II trial. MethodsTreatment-naïve patients with stage IV NSCLC harboring an activating EGFR mutation were enrolled. Alternating cycles of osimertinib (80 mg/day) followed by afatinib (20 mg/day) were administered every 8 weeks. Genomic analysis was performed using circulating tumor DNA obtained before and after the treatment. ResultsAmong the 46 enrolled patients, the median progression-free survival was 20.2 months. The overall response rate was 69.6%. The median overall survival was not reached. Among the 26 plasma samples obtained after the acquisition of resistance, 3 showed an increased MET gene copy number, and 1 showed BRAF mutation. Meanwhile, no EGFR secondary mutation was detected. ConclusionThe efficacy of our treatment was not significantly different from osimertinib alone, as reported previously in untreated advanced NSCLC patients with EGFR mutations. Although the sample size was limited, this treatment may prevent the emergence of EGFR secondary mutations that trigger drug resistance. Further studies are warranted to establish the significance of this treatment. Clinical Trial RegistrationjRCTs051180009.

Artificial neural network model analysis in T790M detection after failure of first- and second-generation epidermal growth factor receptor tyrosine kinase inhibitors.

e21041 Background: Despite osimertinib availability, first or second generation (1st/2nd gen.) epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) are commonly used in many countries. Clinical factors identified before first line EGFR TKIs treatment that correlate with T790M occurrence are not well-known. In this single center retrospective study we define the artificial intelligence-based model that support T790M detection in daily practice. Methods: In 80 patients (pts) consecutively progressed on 1st/2nd generation EGFR TKIs T790M mutation was assessed. In multivariate logistic regression factors predictive to T790M mutation were identified. Based on clinical and molecular factors present before EGFR TKIs initiation multi-layer perceptron (MLP) neural network was used for building model classifying patients according to T790M status. The artificial neural network consisted of three layers: input, hidden and output layers of 36, 6 (optimally due to the result of the neural network) and 1 neurons, respectively. During the learning process the weight links between the neurons were modified using Broyden-Fletcher-Goldfarb-Shanno algorithm. To calculate the diagnostic quality of the artificial neural network, we divided at random of all patients for two groups: training and testing. The training group contained 65 and testing group 15 cases. Sensitivity and specificity for both models were assessed. TIBCO Software Inc., Statistica (data analysis software system), version 13 software was used for all calculations. Results: In 49/80 pts (61.3%) T790M was present. In logistic regression model: del19 EGFR mutation, chest or liver metastases and 1st gen. TKI treatment correlated with T790M presence. Parameters included in building neural network model were: del19/L858R/other EGFR mutation status, sex, age, 1st/2nd gen. TKI in first line, clinical stage, metastases location, ECOG PS, smoking history. Learning and testing phase models detected T790M with sensitivity-94.7%, specificity – 91.3% and sensitivity-77.8%, specifity-83.3%. In testing set (15 pts) proposed neural network model achieved 80% accuracy in predicting correctly T790M status. Clinical stage, TKI generation in first line, metastases location, EGFR mutation were the most valuable entrance parameters. After conducting a sensitivity analysis for all 8 the analysed variables the observed error quotients were above 1, therefore, they are all significance and should be entered as input to the developed network. Conclusions: The proposed artificial neural network model used parameters identified before start of TKI treatment and achieved high accuracy in T790M status prevalence. Although this model need to be validated in large cohort it can be an useful tool to support clinicians decision.

A pilot study of anlotinib with third-generation epidermal growth factor receptor tyrosine kinase inhibitors in untreated EGFR-mutant patients with advanced non-small cell lung cancer.

In recent years, osimertinib, a third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), has been recommended as a first-line treatment for EGFR-mutant advanced non-small cell lung cancer (NSCLC). A phase III study (AENEAS) to assess the efficacy and safety of aumolertinib, another third-generation EGFR-TKI, vs. gefitinib as a first-line treatment in patients with locally advanced or metastatic NSCLC harboring EGFR mutations has also achieved positive results. Despite the improvements in progression-free survival (PFS) and overall survival (OS) of third- vs. first-generation EGFR-TKIs, combined treatment strategies to postpone drug resistance and further prolong survival benefits remain to be explored. We conducted a nonrandomized phase II trial (ChiCTR2000035140) of an oral multitarget antiangiogenic TKI (anlotinib) with third-generation EGFR-TKIs (osimertinib or aumolertinib) in untreated patients with EGFR mutation and advanced NSCLC. Anlotinib and the third-generation EGFR-TKIs were orally administrated (anlotinib at a dose of 12 mg once every other day and osimertinib at 80 mg once daily or aumolertinib at 110 mg once daily). The primary end point of the study was the objective response rate (ORR). Secondary endpoints included the disease control rate (DCR), OS, PFS, and safety of the combined treatment. Enrollment was ceased due to treatment-related adverse events (trAEs) after 11 of 35 planned patients were treated. Among these 11 patients, two were lost to follow-up, and the treatment of five of the remaining nine patients was discontinued due to trAEs, including stomachache, rash, hyponatremia, pulmonary embolism, and interstitial pneumonia. AEs of grade 3 or worse were observed in five patients, but no treatment-related death occurred in these patients. Combining anlotinib and third-generation EGFR-TKIs in untreated EGFR-mutant patients with advanced NSCLC demonstrated significantly increased toxicity, suggesting that the combined treatment strategy was an inappropriate therapeutic choice in this setting.

Regulation of epidermal growth factor receptor tyrosine kinase inhibitor resistance via Ambra1-mediated autophagy in non-small cell lung cancer.

To explore the molecular mechanisms related to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKI) resistance, along with potential therapeutic targets and strategies. The autophagy and Beclin 1 regulator 1 (Ambra1) short hairpin ribonucleic acid (shRNA) lentivirus vector and Ambra1 overexpression plasmid, constructed with a plasmid cloning deoxyribonucleic acid (pcDNA) 3.1 vector, were used to down-regulate and up-regulate Ambra1 expression in the human lung adenocarcinoma erlotinib-resistant cell line (PC9/ER), respectively, as well as to screen stable transgenic cell lines. The IC50 of Erlotinib in these cell lines were measured to determine their resistance status. The real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to measure messenger ribonucleic acid (mRNA) expression of resistance-related genes like multidrug resistance protein 1 (MDR1), multidrug resistance-associated protein 1 (MRP1), and lung drug-resistant-related protein (LRP). Western blot was performed to analyze the protein expressions of the autophagy-related genes Beclin 1, LC3II/I, and p62. Each stable transgenic line formed a tumor under the skin in nude mice; the mice with subcutaneous tumorigenesis of PC9/ER cells and shAmbra1-PC9/ER cells were subsequently treated with rapamycin (RAPA) and chloroquine (CQ), respectively. The mRNA expressions of MDR1, MRP1, and LRP in each tumor tissue sample were detected by qRT-PCR. The protein expressions of adenosine monophosphate-activated protein kinase (AMPK), phosphorylated-AMPK (p-AMPK), forkhead box O3 (FoxO3a), and phosphorylated forkhead box O3 (p-FoxO3a) in the AMPK/FoxO3a signaling pathway were analyzed via Western blot. The qRT-PCR result revealed that the level of Ambra1 in EGFR-TKI-resistant cells had increased. This was further exacerbated by the overexpression of Ambra1 and was reduced after its inhibition. Additionally, Ambra1 upregulated the mRNA expression of drug-resistant genes and the expression of autophagy-related proteins. Subcutaneous tumorigenesis of RAPA-treated shAmbra1-PC9/ER cells resulted in increased expression of drug resistance-related genes and a concomitant decrease in p-AMPK and increase in p-FoxO3a. The results revealed that Beclin-1/β-actin, p62/β-actin, and LC3II/I in the model group were all significantly increased compared to the control group, with P<0.05. Compared to the model group, Beclin-1/β-actin, p62/β-actin, and LC3II/I were all significantly higher in the pcDNA-Ambra1 group, with P<0.05. Compared to the model group, Beclin-1/β-actin, p62/β-actin, and LC3II/I were all significantly decreased in the shAmbra1 group, with P<0.05. Thus, these data suggest that Ambra1 promotes cellular autophagy. In addition, subcutaneous tumorigenesis of CQ-treated shAmbra1-PC9/ER cells resulted in reduced expression of drug resistance-related genes, and a concomitant increase in p-AMPK and decrease in p-FoxO3a. The results of this study revealed that Ambra1-mediated autophagy regulated EGFR-TKI resistance in NSCLC, most probably through the AMPK/FoxO3a signaling pathway.

Concurrent EGFR wild-type tongue squamous cell carcinoma and EGFR-mutant lung adenocarcinoma and response to osimertinib.

e18074 Background: Epidermal growth factor receptor (EGFR) mutation is most commonly oncogenic driver in lung adenocarcinoma with 50% incidence in Asians.Osimertinib is the third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), which has been widely used in metastatic EGFR-mutant non-small cell lung cancer (NSCLC) and has significantly improved outcomes. At present, the treatment of HNSCC mainly relies on surgery or chemoradiotherapy. EGFR is overexpressed in more than 90% of head and neck squamous cell carcinoma (HNSCC). Targeted therapy for HNSCC is mainly monoclonal antibodies, while the application of small molecule inhibitors is limited. The EGFR-TKI can only be applied in subsequent-line, when disease progression on or after platinum therapy. However, the efficacy of EGFR-TKI in patients with both NSCLC and HNSCC remains unclear. Methods: We searched all patients with EGFR-mutation metastatic non-small cell lung cancer and HNSCC who used EGFR-TKI in the Second Xiangya Hospital. Tumor sections were assessed immunohistochemically using PD-L1 and EGFR expression. EGFR amplification was detected by fluorescence in situ hybridization (FISH). We collected clinical characteristics and treatment histories for all patients including time to progression on EGFR-TKI. Time to progression on EGFR-TKI was defined as time from start of EGFR-TKI to time of radiographic RECIST progression. The efficacy and prognosis were evaluated based on the RECIST (version 1.1). Results: We found an advanced lung adenocarcinoma patient who harbored an EGFR-mutation and concurrently had tongue squamous cell carcinoma with EGFR wild-type.The tongue tumor tissue sample for EGFR expression was positive by immunohistochemistry and EGFR amplification was negative by FISH. NGS showed inactive mutation of patched1 (PTCH1) and EGFR wild-type.PET-CT scans demonstrated a partial response (PR) of the lung tumor and tongue cancer after two months of treatment of osimertinib. The lung tumor maintian partial response until now (nearly 30 months). And the tongue tumor reached the first progression- free survival (PFS) at 21 months. Conclusions: The patient with NSCLC and tongue cancer who exhibited objective response to EGFR-TKI, osimertinib monotherapy. The result indicates a clear response of tongue cancer to osimertinib and the potential for the use of osimertinib in tongue cancer. However, with the specific mechanism largely unknown, it is necessary to study further the effect of osimertinib on HNSCC.

Study on the therapeutic effect of epidermal growth factor receptor tyrosine kinase inhibitors in non-small cell lung cancer patients.

Study on the therapeutic effect of epidermal growth factor receptor tyrosine kinase inhibitors in non-small cell lung cancer patients.

Potential components and mechanism of Liangxue Tuezi Mixture in treating Henoch-Schönlein purpura based on network pharmacology and metabolomics

Ultra-performance liquid chromatography-quadrupole time of fight/mass spectrometry(UPLC-Q-TOF-MS) and UNIFI were employed to rapidly determine the content of the components in Liangxue Tuizi Mixture. The targets of the active components and Henoch-Schönlein purpura(HSP) were obtained from SwissTargetPrediction, Online Mendelian Inheritance in Man(OMIM), and GeneCards. A &quot;component-target-disease&quot; network and a protein-protein interaction(PPI) network were constructed. Gene Ontology(GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analysis were performed for the targets by Omishare. The interactions between the potential active components and the core targets were verified by molecular docking. Furthermore, rats were randomly assigned into a normal group, a model group, and low-, medium-, and high-dose Liangxue Tuizi Mixture groups. Non-targeted metabolomics was employed to screen the differential metabolites in the serum, analyze possible metabolic pathways, and construct the &quot;component-target-differential metabolite&quot; network. A total of 45 components of Liangxue Tuizi Mixture were identified, and 145 potential targets for the treatment of HSP were predicted. The main signaling pathways enriched included resistance to epidermal growth factor receptor tyrosine kinase inhibitors, phosphatidylinositol 3-kinase/protein kinase B(PI3K-AKT), and T cell receptor. The results of molecular docking showed that the active components in Liangxue Tuizi Mixture had strong binding ability with the key target proteins. A total of 13 differential metabolites in the serum were screened out, which shared 27 common targets with active components. The progression of HSP was related to metabolic abnormalities of glycerophospholipid and sphingolipid. The results indicate that the components in Liangxue Tuizi Mixture mainly treats HSP by regulating inflammation and immunity, providing a scientific basis for rational drug use in clinical practice.

Droplet digital PCR as an alternative method for detecting MET amplification in patients with non-small cell lung cancer.

e15107 Background: Mesenchymal-epithelial transition (MET) amplification is associated with resistance to epidermal growth factor receptor tyrosine kinase inhibitors in lung cancer patients and poor prognosis. Fluorescence in situ hybridization (FISH) is the most commonly used method for detecting MET amplification but is not possible in cases where tissue samples are unavailable. Here, we evaluated the utility of droplet digital PCR (ddPCR) in detecting MET amplification in non-small cell lung cancer (NSCLC) patients. Methods: We evaluated a c-Met: EFTUD ddPCR assay of the c-Met gene and using EFTUD as the reference gene to determine c-Met amplification in plasma cfDNA samples from 80 advanced NSCLC patients. A total of 84 plasma samples were collected for MET amplification detection using ddPCR. Paired tissue samples using FISH were to evaluate the correlation between the MET-ddPCR ratio and MET FISH. Results were correlated with clinical findings. Results: We found that ddPCR had an 88.1% concordance rate with FISH in detecting MET CNG, with an area under the curve (AUC) of 0.84. Eleven patients were positive for MET amplification by FISH prior to MET inhibitor treatment, and these patients had a partial response rate (PR) of 45.5% and a median progression-free survival (PFS) of 12.1 months. However, MET amplification identified by ddPCR failed to distinguish significant clinical outcomes. The PR rate and median PFS for ddPCR-positive vs. negative patients were 57.1% vs. 50.0% and 12.1 months vs. 2.1 months (P = 0.276). Conclusions: Our results suggest that ddPCR is a reliable alternative to detect MET amplification in plasma cfDNA samples. Met status determined in cfDNA may have potential as a predictive factor for PFS after c-Met inhibitor therapy.

CO163 Associations between Epidermal Growth Factor Receptor-Tyrosine Kinase Inhibitors (EGFR-TKIS) and Venous Thromboembolism Among Older Patients with Advanced Non-Small Cell Lung Cancer (NSCLC)

Venous thromboembolism (VTE), including deep venous thromboembolism (DVT) and pulmonary embolism (PE), poses clinical and economic burdens in patients with advanced non-small cell lung cancer (NSCLC). However, little is known about the risk of developing VTE in patients with NSCLC receiving epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). We aim to compare the risk of developing VTE after initiating different EGFR-TKIs in older patients with advanced NSCLC.

Aumolertinib with chemotherapy or alone compared with osimertinib in patients with EGFR-mutant non–small-cell lung cancer (TREBLE).

TPS9153 Background: Aumolertinib is a novel third-generation (3G) epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI). Safety and efficacy of aumolertinib have been demonstrated in patients with EGFR-mutated locally advanced or metastatic (LA/m) NSCLC. (Lu, 2021; Lu, 2022) A phase 3 study in these patients in the first-line setting showed a significant improvement in progression-free survival (PFS) for aumolertinib vs gefitinib (median 19.3 months versus 9.9 months; P &lt; 0.0001). Aumolertinib was generally well-tolerated. (Lu, 2022) Aumolertinib is approved in China for patients with LA/m NSCLC who have an EGFR T790M resistance mutation upon disease progression and for treatment naïve patients with EGFR-mutated NSCLC. Studies evaluating first-generation EGFR-TKI + chemotherapy (chemo) showed improved PFS in select patient populations. (Hosomi, 2019) It is unclear if the addition of chemo to a 3G EGFR-TKI will improve PFS in patients with EGFR-mutated LA/m NSCLC. As the addition of chemo to a 3G EGFR-TKI may prove warranted, there is a need to understand the relative efficacy and safety in the diversity of patients encountered in routine clinical practice. (Tanaka, 2021). Methods: This is a randomized, multi-regional, phase 3 clinical trial comparing aumolertinib + chemo or aumolertinib monotherapy with osimertinib monotherapy. Patients are eligible if they have stage IIIB, IVA, or IVB NSCLC; harbor ex19del or L858R EGFR mutations alone or with other EGFR mutations; and have an ECOG PS of ≤2. Patients are ineligible if they received prior systemic therapy for mNSCLC or are a candidate for curative intent therapy. Eligible patients will be randomized 2:2:1 and stratified by mutation status (ex19del or L858R), ECOG PS (0 vs 1/2), and race (White vs Asian vs other races combined). Anticipated enrollment is 500 patients; 200 to receive aumolertinib + chemo (110 mg PO QD aumolertinib + investigator's choice chemo), 200 to receive osimertinib (80 mg PO QD), and 100 to receive aumolertinib (110 mg PO QD). The primary endpoint is PFS, by blinded independent review committee (BICR) per RECIST 1.1, for aumolertinib + chemo vs osimertinib. Overall survival (OS) is a key secondary endpoint for aumolertinib + chemo vs osimertinib. Additional efficacy endpoints will be assessed for aumolertinib + chemo vs osimertinib and aumolertinib vs osimertinib, as well as safety and patient reported outcomes. Exploratory endpoints include characterizing mechanisms of acquired resistance across all arms, CNS efficacy, and exposure-response relationship. Enrollment began in July 2022. The study is currently recruiting and will include approximately 200 sites globally. The study design will provide a power of 80% at a 2-sided Type I error of 0.05 for the primary endpoint. If the primary endpoint is statistically significant, a sequential test method will be used to evaluate OS. Clinical trial information: NCT05493501 .

AX-0085, a novel AXL kinase inhibitor, and effects on osimertinib-resistance in non–small-cell lung cancer.

e15121 Background: Osimertinib is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) having high efficacy in treating patients with advanced non-small cell lung cancer (NSCLC) with EGFR activating mutations and EGFR T70M mutations. Although, osimertinib is a frontline anticancer agent for treating NSCLC, many patients inevitably develop osimertinib-resistance tumor recurrence. The activation of AXL was reported to be a major factor driving osimertinib-resistance in NSCLC. Thus, AXL is a promising therapeutic target for the treatment of osimertinib-resistant NSCLC, and we developed a new small-molecule AXL inhibitor, AX-0085. Methods: We established osimertinib-resistant cell lines from EGFR-mutated NSCLC cell lines, HCC827 and H1975, after high dose exposure and stepwise exposure to osimertinib in culture. We investigated the cell viability of AX-0085 and other kinase inhibitors, and the anti-tumor activity of AX-0085 on the proliferation, migration, apoptosis, and epithelial-mesenchymal transition (EMT) in osimertinib-resistant cells. Results: Compared to the parental cells, IC50 of resistant cell to osimertinib was significantly increased and osimertinib-resistant cells showed remarkably increased expression of AXL/pAXL and p-SRC as compared to the parental HCC827 cell. AX-0085 was completely blocked the AXL and SRC activation but EGFR inhibitors (gefitinib and osimertinib) did not inhibit the activation of AXL and SRC in the osimertinib-resistant cell line. AX-0085 (IC50: 4.4nM for AXL kinase in cell-based kinase assay) was one of the most potent AXL inhibitors and showed the strongest cytotoxicity against osimertinib-resistant cells compared to other kinase inhibitors. AX-0085 effectively down-regulated mRNA level of AXL and AXL regulating transcription factors in NSCLC cell lines such as HCC827 and H1975. AX-0085 treatment effectively inhibited the activation of AXL in acquired osimertinib-resistant cells and decreased the mRNA level of AXL and AXL regulating transcription factors. AX-0085 significantly inhibited the cell proliferation, apoptosis, migration, and EMT in acquired osimertinib-resistant cells. Conclusions: Our results showed that AX-0085 selectively inhibits the activation of AXL to overcome acquired resistance to osimertinib, suggesting an effective AXL-based therapy for patients with osimertinib-resistant tumors. Currently, AX-0085 is undergoing non-clinical trials.

Safety and preliminary efficacy of YK-029A, a novel EGFR TKI, in patients with advanced NSCLC harboring ex20ins, T790M or rare mutations.

9014 Background: This study aimed to evaluate the safety and preliminary efficacy of YK-029A, a novel third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, in treated or untreated patients with advanced NSCLC. Methods: This dose-escalation and dose-expansion phase 1 trial recruited previously untreated or treated patients with EGFR ex20ins mutant locally advanced or metastatic NSCLC and previously treated patients with EGFR T790M or rare mutations. In dose-escalation phase, patients with EGFR T790M mutation were enrolled. YK-029A was given at doses of 50, 100, 150, 200 to 250 mg/day (3+3 design). In dose-expansion phase, patients with EGFR T790M, EGFR ex20ins, or rare mutations were enrolled. The primary objective was safety. Dose-limiting toxicity (DLT) and maximum tolerated dose (MTD) were explored. In the treatment-naïve cohort of EGFR ex20ins mutant NSCLC, patients were administered oral YK-029A 200 mg once daily in a 28-day cycle, and efficacy was assessed by the independent review committee. The study was registered (chinadrugtrials.org.cn,CTR20180350). Results: A total of 108 were included in the safety analysis set. DLT did not occur in dose-escalation phase. MTD was not reached. Treatment-emergent adverse events (TEAEs) of any grade and grade≥3 occurred in 106 (98.1%) and 41 (38.0%) patients, respectively. Treatment-related adverse events (TRAEs) of any grade and grade≥3 occurred in 102 (94.4%) and 30 (27.8%) patients, respectively. One patient had liver abscess related to YK-029A and died. Three patients terminated the treatment because of TEAEs. The most common TRAEs were diarrhea (46.3%), anemia (38.0%), and rash (32.4%). For the treatment-naïve EGFR ex20ins mutant cohort, 26 patients were included in the efficacy analysis set. Most patients were adenocarcinoma (96.4%) and at stage IV (85.7%). At the cut-off date on October 30, 2022, 19 patients (73.1%) had partial remission, five patients (19.2%) had stable disease, and two patients (7.7%) developed disease progression. The confirmed objective response rate achieved 73.1% (95% confidence interval [CI], 52.21% to 88.43%). The median progression-free survival was 9.3 months (95% CI, 5.85 to not evaluated). Conclusions: YK-029A was well tolerated and showed preliminary efficacy in treatment-naïve EGFR ex20ins mutant patients with locally advanced or metastatic NSCLC. [Table: see text]

EGRET: A first-in-human study of the novel antibody-drug conjugate (ADC) AZD9592 as monotherapy or combined with other anticancer agents in patients (pts) with advanced solid tumors.

TPS3156 Background: The epidermal growth factor receptor (EGFR) and mesenchymal-epidermal transition tyrosine kinase receptor (c-MET) are expressed in diverse solid tumors, and function as driver genes in some types. Clinical benefit of bispecific monoclonal antibodies (Ab) targeting these receptors was demonstrated in pts with EGFR mutated (EGFRm) non-small-cell lung cancer (NSCLC), but an ADC targeting these receptors has not been developed. AZD9592 is an ADC with a bispecific Ab targeting EGFR and c-MET. When internalized, AZD9592 releases a topoisomerase 1 inhibitor (TOP1i) warhead that traps TOP1 on DNA, causing double-strand breaks and induction of apoptotic cell death. Preclinical data have demonstrated promising efficacy and safety of AZD9592 in tumors expressing EGFR and c-MET, including but not limited to adenocarcinoma and squamous NSCLC and head and neck squamous cell carcinoma (HNSCC). Methods: EGRET is a phase 1, open-label, multicenter, modular study in pts with advanced solid tumors (NCT05647122). Module 1 will evaluate AZD9592 monotherapy in pts with metastatic NSCLC (mNSCLC) with EGFRm (sensitizing L858R mutation or exon 19 deletions) or EGFR wild-type, or recurrent or metastatic HNSCC. Module 2 will evaluate AZD9592 in combination with osimertinib in pts with EGFRm mNSCLC. Each module will include dose escalation (Part A) and dose expansion (Part B) cohorts. Key inclusion criteria are age ≥18 years, ECOG performance status 0–1, life expectancy ≥12 weeks, measurable disease per RECIST v1.1, and adequate organ and bone marrow function. Key exclusion criteria for both modules include unresolved toxicities of Grade ≥2 (NCI CTCAE v5.0) from prior therapy, uncontrolled intercurrent illness, cardiovascular disorders, history of drug-induced interstitial lung disease or pneumonitis, and previous treatment with a TOP1i ADC or an EGFR- or MET-targeted ADC. Treatment continues until disease progression, initiation of alternative anticancer therapy or unacceptable toxicity. The primary objectives of Part A are to assess safety and tolerability, and to determine the maximum tolerated dose and/or the recommended phase 2 dose of AZD9592 as monotherapy or in combination with osimertinib. The primary objectives for Part B are to evaluate safety and tolerability, and antitumor activity by investigator-assessed objective response rate (ORR) according to RECIST v1.1. Secondary objectives for both Part A and B include assessing AZD9592, as monotherapy and in combination with osimertinib, for efficacy (by ORR, disease control rate, duration of response, and progression-free and overall survival), pharmacokinetics, and immunogenicity. Descriptive statistics will be used for all variables. The study will include sites across the EU, USA, and Asia Pacific; sites in USA and Australia are currently open for enrollment. Clinical trial information: NCT05647122 .

Retreatment with EGFR inhibitor in non-small cell lung cancer patients previously exposed to EGFR-TKI: A systematic review and meta-analysis.

e21159 Background: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) are the standard therapy for EGFR-mutated non-small cell lung cancer (NSCLC) patients. Unfortunately, patients eventually develop resistance to EGFR-TKI and disease progression. Re-exposure after a drug-free interval may be an alternative to overcome tumor resistance. We performed a systematic review and meta-analysis to assess EGFR-TKI retreatment’s efficacy in advanced NSCLC. Methods: We systematically searched PubMed, Embase, and Cochrane databases for clinical trials and observational cohort studies evaluating EGFR-TKI retreatment in advanced NSCLC patients. We aimed to assess the objective response rate (ORR), disease control rate (DCR), and survival outcomes. Subgroup analyses were performed according to the type of EGFRmutation and the TKI drug used in retreatment. We further stratified studies to assess the efficacy of rechallenging with the same drug used initially or a different one. Heterogeneity was assessed using the Cochran Q test, and I2 statistics and random effects models were fitted. Results: We included 16 studies (7 prospective clinical trials, and 9 retrospective cohorts) with 806 patients. Most of them had adenocarcinoma (70.8%), were females (58.1%), and were non-smokers (74.5%). The most frequently TKI given as the initial treatment was gefitinib (58.1%), whereas in the rechallenge it was erlotinib (36.6%) followed by gefitinib (31.6%). In a pooled analysis of patients who were retreated with TKI, the median PFS was 4.1 months (95%CI 3.0 - 4.4), and OS was 12.6 months (95%CI 10.2 - 12.6). ORR was 16% (95%CI 10 - 22%) and DCR was documented in 63% (95%CI 0.54 - 0.72%). Patients harboring a sensitive EGFR mutation had a significantly higher DCR, compared to patients with EGFRT790M mutation, and those with unknown mutational status, (DCR: 70%, 62%, and 48%, respectively, p = 0.02). Patients rechallenged with gefitinib, erlotinib, or afatinib had a similar DCR of 60%, while patients re-exposed to osimertinib had a greater DCR of 70% (95%CI 59 - 80%), (p &lt; 0.01). Regarding ORR, no significant difference was observed amongst the groups defined by the type of EGFR mutation (p = 0.74) or type of TKI used (p = 0.05). Rechallenge using the same versus a different TKI resulted in similar ORR and DCR. In a subgroup analysis of 102 patients who had disease control with the first TKI, 62% (95%CI 45 – 79%) achieved disease control with TKI rechallenge. Conclusions: Our meta-analysis suggests that a subgroup of advanced EGFR-mutated NSCLC patients who failed TKI treatment benefit from rechallenge with an EGFR-TKI after a TKI-free interval. Re-exposure with either the same or a different TKI was shown to be equally effective. Patients treated with osimertinib and those with EGFR-sensitive mutations have better responses to the treatment.

Rechallenge of afatinib for EGFR-mutated non-small cell lung cancer previously treated with osimertinib: a multicenter phase II trial protocol (REAL study).

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have revolutionized the treatment of advanced non-small cell lung cancer (NSCLC) and contributed to the development of precision medicine. Osimertinib is a standard first-line (1L) treatment for EGFR-mutated NSCLC and has demonstrated superior survival benefits over previous-generation TKIs. However, resistance to osimertinib is nearly inevitable, and subsequent treatment strategies remain unmet medical needs in this setting. Afatinib, a second-generation EGFR-TKI, exhibits activity against certain uncommon EGFR mutation types in the 1L setting. There are a few case reports on the efficacy of afatinib against EGFR-dependent resistance after osimertinib treatment, although these have not been prospectively investigated. The present phase II, single-arm multicenter trial aims to verify the efficacy and safety of afatinib rechallenge after 1L osimertinib resistance. Patients (aged ≥20 years) with advanced or recurrent non-squamous NSCLC harboring drug-sensitive EGFR mutations (deletion of exon 19 or L858R) who were previously treated with 1L osimertinib and second-line chemotherapy other than TKIs are considered eligible. Undergoing next-generation sequence-based comprehensive genomic profiling is one of the key inclusion criteria. The primary endpoint is the objective response rate; the secondary endpoints are progression-free survival, overall survival, and tolerability. Thirty patients will be recruited in December 2023. The results of this study may promote incorporating afatinib rechallenge into the treatment sequence after 1L osimertinib resistance, a setting in which concrete evidence has not been yet established. UMIN Clinical Trial Registry: UMIN000049225.

Acute osimertinib exposure induces electrocardiac changes by synchronously inhibiting the currents of cardiac ion channels.

Introduction: As the third generation of epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), osimertinib has demonstrated more significant cardiotoxicity than previous generations of EGFR-TKIs. Investigating the mechanism of osimertinib cardiotoxicity can provide a reference for a comprehensive understanding of osimertinib-induced cardiotoxicity and the safety of the usage of this drug in clinical practice. Methods: Multichannel electrical mapping with synchronous ECG recording was used to investigate the effects of varying osimertinib concentrations on electrophysiological indicators in isolated Langendorff-perfused hearts of guinea pigs. Additionally, a whole-cell patch clamp was used to detect the impact of osimertinib on the currents of hERG channels transfected into HEK293 cells and the Nav1.5 channel transfected into Chinese hamster ovary cells and acute isolated ventricular myocytes from SD rats. Results: Acute exposure to varying osimertinib concentrations produced prolongation in the PR interval, QT interval, and QRS complex in isolated hearts of guinea pigs. Meanwhile, this exposure could concentration-dependently increase the conduction time in the left atrium, left ventricle, and atrioventricular without affecting the left ventricle conduction velocity. Osimertinib inhibited the hERG channel in a concentration-dependent manner, with an IC50 of 2.21 ± 1.29μM. Osimertinib also inhibited the Nav1.5 channel in a concentration-dependent manner, with IC50 values in the absence of inactivation, 20% inactivation, and 50% inactivation of 15.58 ± 0.83μM, 3.24 ± 0.09μM, and 2.03 ± 0.57μM, respectively. Osimertinib slightly inhibited the currents of L-type Ca2+ channels in a concentration-dependent manner in acutely isolated rat ventricular myocytes. Discussion: Osimertinib could prolong the QT interval; PR interval; QRS complex; left atrium, left ventricle, and atrioventricular conduction time in isolated guinea pig hearts. Furthermore, osimertinib could block the hERG, Nav1.5, and L-type Ca2+ channels in concentration-dependent manners. Therefore, these findings might be the leading cause of the cardiotoxicity effects, such as QT prolongation and decreased left ventricular ejection fraction.