EGFR-mutant Non-small Cell Lung Cancer Research Articles

1272P Updated results from a first-in-human, phase I/II study of GB263T, a novel EGFR/cMET/cMET tri-specific antibody, in patients with advanced EGFR-mutated (EGFRm) non-small cell lung cancer (NSCLC)

1272P Updated results from a first-in-human, phase I/II study of GB263T, a novel EGFR/cMET/cMET tri-specific antibody, in patients with advanced EGFR-mutated (EGFRm) non-small cell lung cancer (NSCLC)

Discovery of flavonoid-containing compound Lupalbigenin as anti-NSCLC cancer agents via suppression of EGFR and ERK1/2 pathway

Epidermal growth factor receptor exon 20 insertions (EGFR Ex20ins) driver mutations in non–small cell lung cancer (NSCLC) is insensitive to EGFR tyrosine kinase inhibitors (TKIs). Therefore, it is necessary to develop more novel strategy to address the limitations of existing therapies targeting EGFR-mutated NSCLC. Lupalbigenin (LB), a flavonoid compound extracted from Derris scandens, has shown preclinical activity in lung cancer. However, the activity of LB in Ex20ins-driven tumors has not yet been elucidated. In this study, a series of stable BaF/3 cell-line that contains a high proportion (>90 %) of EGFR-eGFP Ex20ins were generated using an IL3-deprivation method. Ba/F3 cell models harboring dissimilar Ex20ins were used to characterize the antineoplastic mechanism of LB. Molecular docking confirmed that the LB could effectively bind to key target EGFR. The in vitro anticancer activity of LB was investigated in engineered Ba/F3 cells bearing diverse uncommon EGFR mutations. LB was shown to be more potent in inhibiting the viability of various uncommon EGFR-mutated cell lines. Mechanistic studies disclosed that LB repressed EGFR phosphorylation and downstream survival pathways in Ba/F3 cells expressing EGFR Ex20ins, resulting in caspase activation by activating the intrinsic apoptotic pathway. Further analyses showed that LB significantly induced G0/G1 cell cycle arrest and apoptosis in cells. LB also reduced the protein expression levels of CDK4, CDK6, CDK8, cyclin D1, cyclin A2, and Bcl2 and promoted the expression of cytochrome C, p27, and p53. In summary, we explored the possible potential targets of LB through network pharmacology and verified the target using in vitro experiments. Furthermore, our results demonstrated that LB showed potential anti-Ex20ins cancer activity through suppression of the EGFR and ERK1/2 signaling pathway in Ba/F3 cells bearing two to three amino acid insertion mutations. These findings suggested that LB might be valuable for further investigation as a potential candidate in the treatment of associated diseases.

Macrophage-induced Expression of TonEBP/NFAT5 Is Associated With Gefitinib Resistance and Migration in PC-9 Cells.

Macrophages prevail in the microenvironment of several tumors, including non-small-cell lung cancer (NSCLC), where they secrete pro-tumorigenic factors that contribute to cancer progression. This study investigated the role of macrophages on the resistance of epidermal growth factor receptor (EGFR)-mutated NSCLC cells to tyrosine kinase inhibitors (TKIs). EGFR-mutated cell lines PC-9 and HCC827 were cocultured with macrophages and treated with TKIs (erlotinib and gefitinib). The effects of the macrophage-conditioned medium (macrophage CM) on gefitinib resistance and cell migration were also evaluated. Co-culture with macrophages significantly enhanced the resistance to erlotinib and gefitinib in PC-9 and HCC827 cells compared to that in cells cultured independently. Macrophage CM markedly induced gefitinib resistance in PC-9 cells, with maximum resistance observed at 50% CM concentration. This resistance persisted for up to 48 h post-CM removal. Macrophage CM inhibited gefitinib-induced apoptosis, as evidenced by the decreased expression of cleaved caspase-3, PARP, and BIM. Additionally, macrophage CM increased the migration ability of PC-9 cells, as shown by the wound healing and transwell migration assays. Studies have shown that TonEBP is crucial in cancer metastasis and drug resistance; we found that inhibition of TonEBP/NFAT5 expression reduced gefitinib resistance and migration in macrophage CM-induced PC-9 cells, indicating its role as mediator of these effects. Macrophages contribute to TKI resistance and enhance the migration of EGFR-mutated NSCLC cells through mechanisms involving TonEBP/NFAT5. Therefore, targeting TonEBP/NFAT5 represents a potential therapeutic strategy for overcoming macrophage-induced TKI resistance in NSCLC cells.

Clinical utility of repeated rebiopsy for EGFR T790M mutation detection in non-small cell lung cancer.

In cases where rebiopsy fails to find the epidermal growth factor receptor (EGFR) T790M mutation, the criteria for selecting patients for repeated rebiopsy remains unclear. This study aimed to assess the impact of repeated rebiopsy on T790M mutation detection in non-small cell lung cancer (NSCLC) patients. Patients with advanced EGFR-mutated NSCLC between January 2018 and December 2021 at three-referral hospitals in South Korea underwent retrospective review. Of 682 patients who had rebiopsy after disease progression, T790M mutation status was assessed in plasma circulating tumor DNA (ctDNA) and/or tumor tissues. The overall T790M positivity rate increased from 40.8% after the first rebiopsy to 52.9% following multiple rebiopsies in the entire study population. Longer duration of initial EGFR TKI use (OR 1.792, ≥8 months vs. <8 months, p=0.004), better EGFR TKI responses (OR 1.611, complete or partial response vs. stable disease, p=0.006), presence of bone metastasis (OR 2.286, p<0.001) were correlated with higher T790M positivity. Longer EGFR TKI use and better responses increased T790M positivity in repeated tissue rebiopsy, while bone metastasis favored liquid rebiopsy. Additionally, T790M status has been shown to be positive over time through repeated rebiopsies ranging from several months to years, suggesting its dynamic nature. In this study, among patients who initially tested negative for T790M in rebiopsy, repeated rebiopsies uncovered an additional 23.5% T790M positivity. Particularly, it is suggested that repeated rebiopsies may be valuable for patients with prolonged EGFR TKI usage, better responses to treatment, and bone metastasis.

Cost-effectiveness of adjuvant icotinib versus chemotherapy for patients with stage II–IIIA EGFR-mutated non-small cell lung cancer in China

ObjectiveIcotinib has been approved for adjuvant treatment of stage II–IIIA non-small cell lung cancer (NSCLC) patients with activating epidermal growth factor receptor (EGFR) mutations in China, yet the long-term costs...

Chitinase 3-like-1 (CHI3L1) in the pathogenesis of epidermal growth factor receptor mutant non-small cell lung cancer

Non-small cell lung cancer (NSCLC) accounts for 85 % of all lung cancers. In NSCLC, 10–20 % of Caucasian patients and 30–50 % of Asian patients have tumors with activating mutations in the Epidermal Growth Factor Receptor (EGFR). A high percentage of these patients exhibit favorable responses to treatment with tyrosine kinase inhibitors (TKI). Unfortunately, a majority of these patients develop therapeutic resistance with progression free survival lasting 9–18 months. The mechanisms that underlie the tumorigenic effects of EGFR and the ability of NSCLC to develop resistance to TKI therapies, however, are poorly understood. Here we demonstrate that CHI3L1 is produced by EGFR activation of normal epithelial cells, transformed epithelial cells with wild type EGFR and cells with cancer-associated, activating EGFR mutations. We also demonstrate that CHI3L1 auto-induces itself and feeds back to stimulate EGFR and its ligands via a STAT3-dependent mechanism(s). Highly specific antibodies against CHI3L1 (anti-CHI3L1/FRG) and TKI, individually and in combination, abrogated the effects of EGFR activation on CHI3L1 and the ability of CHI3L1 to stimulate the EGFR axis. Anti-CHI3L1 also interacted with osimertinib to reverse TKI therapeutic resistance and induce tumor cell death and inhibit pulmonary metastasis while stimulating tumor suppressor genes including KEAP1. CHI3L1 is a downstream target of EGFR that feeds back to stimulate and activate the EGFR axis. Anti-CHI3L1 is an exciting potential therapeutic for EGFR mutant NSCLC, alone and in combination with osimertinib or other TKIs.

Exposure-response modelling of osimertinib in patients with non-small cell lung cancer.

Osimertinib is a third-generation, irreversible, central nervous system-active, epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) with efficacy in EGFR-mutated non-small cell lung cancer (NSCLC). We assessed the relationship between plasma osimertinib levels and its efficacy and safety events. Comprehensive pharmacokinetics exposure-response (E-R) modelling was performed utilizing steady state area under the curve (AUCss) data from first-line, ≥second-line and adjuvant studies from the osimertinib clinical development programme (20-240 mg once-daily dosing; N = 1689 patients). Analyses were conducted for survival using a proportional hazard model; for interstitial lung disease (ILD) and left ventricular ejection fraction (LVEF) events using a penalized logistic regression model and graphical analysis of potential confounding factors; and for rash and diarrhoea events using descriptive analysis. E-R modelling analyses indicated no clear trend of increasing efficacy with increasing osimertinib AUCss; efficacy in all exposure quartiles was significantly better than the control arm (comparator EGFR-TKI, chemotherapy or placebo) irrespective of treatment line. Model-based analysis suggested a potential relationship between increased osimertinib exposure and increased probability of ILD events, predominantly in Japanese patients. Additionally, there were increased probabilities of rash or diarrhoea with increasing osimertinib exposure. The probability of LVEF events showed overlapping confidence intervals for osimertinib ≤80 mg and control. E-R modelling in patients with EGFR-mutated NSCLC demonstrated that increased osimertinib exposure was unlikely to increase efficacy but may increase occurrence of certain adverse events. Hence, long-term treatment with doses ≥80 mg was not expected to provide additional benefit.

Transcriptomic Heterogeneity of EGFR-Mutant Non-Small Cell Lung Cancer Evolution Toward Small-Cell Lung Cancer.

Histologic transformation from EGFR-mutant non-small cell lung cancer (NSCLC) to small-cell lung cancer (SCLC) is a key mechanism of resistance to EGFR tyrosine kinase inhibitors (TKI). However, transcriptomic changes between NSCLC and transformed SCLC (t-SCLC) remain unexplored. We conducted whole-transcriptome analysis of 59 regions of interest through the spatial profiling of formalin-fixed, paraffin-embedded tissues obtained from 10 patients (lung adenocarcinoma, 22; combined SCLC/NSCLC, 7; and t-SCLC, 30 regions of interests). Transcriptomic profiles and differentially expressed genes were compared between pre- and post-transformed tumors. Following EGFR-TKI treatment, 93.7% (15/16) of t-SCLC components evolved into neuroendocrine-high subtypes (SCLC-A or SCLC-N). The transition to t-SCLC occurred regardless of EGFR-TKI treatment and EGFR mutational status, with a notable decrease in EGFR expression (P < 0.001) at both mRNA and protein levels. Pathway analysis revealed that gene overexpression was related to epigenetic alterations in t-SCLC. Interestingly, histone deacetylase inhibitors restored EGFR expression in SNU-2962A cells and their organoid model. The synergistic effects of third-generation EGFR-TKI osimertinib and the histone deacetylase inhibitor fimepinostat were validated in both in vitro and in vivo models. Our study demonstrated that most t-SCLC cases showed neuronal subtypes with low EGFR expression. Differentially expressed gene analysis and t-SCLC preclinical models identified an epigenetic modifier as a promising treatment strategy for t-SCLC.

Efficacy and safety of immune checkpoint inhibitors for individuals with advanced EGFR-mutated non-small-cell lung cancer who progressed on EGFR tyrosine-kinase inhibitors: a systematic review, meta-analysis, and network meta-analysis

The clinical benefits of immune checkpoint inhibitor (ICI)-based treatments in treating individuals with advanced EGFR-mutated non-small-cell lung cancer (NSCLC) who have progressed on EGFR tyrosine-kinase inhibitors (TKIs) remain controversial. We aimed to review the literature to comprehensively investigate the individual and comparative clinical outcomes of various ICI-based treatment strategies in this population. In this systematic review and meta-analysis, we used single-arm, pairwise, and network meta-analytical approaches. We searched PubMed, Embase, Cochrane Library, Web of Science, ClinicalTrials.gov, and relevant international conference proceedings from database inception to Jan 31, 2024, without language restrictions, to identify eligible clinical trials that assessed ICI-based treatments for individuals with advanced EGFR-mutated NSCLC who progressed on EGFR-TKIs. Studies considered eligible were published and unpublished phase 1, 2, or 3 clinical trials enrolling participants with histologically or cytologically confirmed advanced EGFR-mutated NSCLC who had progressed after at least one EGFR-TKI treatment, and that evaluated ICI-based treatment strategies on at least one of the clinical outcomes of interest. The primary outcome analysed was progression-free survival. The protocol is registered with PROSPERO, CRD42021292626. 17 single-arm trials and 15 randomised controlled trials, involving 2886 participants and seven ICI-based treatment strategies (ICI monotherapy, ICI plus chemotherapy [ICI-chemo], ICI plus antiangiogenesis [ICI-antiangio], ICI plus antiangiogenesis plus chemotherapy [ICI-antiangio-chemo], dual ICIs [ICI-ICI], dual ICIs plus chemotherapy [ICI-ICI-chemo], and ICI plus EGFR-TKI [ICI-TKI]), were included. Three of these strategies-ICI monotherapy, ICI-antiangio-chemo, and ICI-chemo-had sufficient data across the included studies to perform a pairwise meta-analysis. The pairwise meta-analysis showed that, compared with chemotherapy, ICI monotherapy led to shorter progression-free survival (hazard ratio [HR] 1·73 [95% CI 1·30-2·29], I2=0%), whereas ICI-antiangio-chemo (HR 0·54 [0·44-0·67], I2=0%) and ICI-chemo (HR 0·77 [0·67-0·88], I2=0%) prolonged progression-free survival. The network meta-analysis showed that ICI-antiangio-chemo yielded the best progression-free survival results, with substantial benefits over ICI-chemo (HR 0·71 [95% credible interval 0·59-0·85]), ICI monotherapy (HR 0·30 [0·22-0·41]), and non-ICI treatment strategies including antiangio-chemo (HR 0·76 [0·58-1·00]) and chemotherapy alone (HR 0·54 [0·45-0·64]). ICI-antiangio-chemo was associated with higher risks of both any-grade and grade 3 or worse adverse events over ICI-chemo and chemotherapy in the network meta-analysis. For individuals with advanced EGFR-mutated NSCLC who progressed on EGFR-TKIs, ICI-antiangio-chemo was identified as the optimal treatment option. The toxicity of this treatment was acceptable but needs careful attention. ICI-chemo showed appreciably greater efficacy than the standard-of-care chemotherapy. These findings clarified the roles of ICI-based treatment strategies in this difficult-to-treat refractory population, potentially complementing recent guidelines. None.

PrPC controls epithelial-to-mesenchymal transition in EGFR-mutated NSCLC: implications for TKI resistance and patient follow-up

Patients with EGFR-mutated non-small cell lung cancer (NSCLC) benefit from treatment with tyrosine kinase inhibitors (TKI) targeting EGFR. Despite improvements in patient care, especially with the 3rd generation TKI osimertinib, disease relapse is observed in all patients. Among the various processes involved in TKI resistance, epithelial-to-mesenchymal transition (EMT) is far from being fully characterized. We hypothesized that the cellular prion protein PrPC could be involved in EMT and EGFR-TKI resistance in NSCLC. Using 5 independent lung adenocarcinoma datasets, including our own cohort, we document that the expression of the PRNP gene encoding PrPC is associated with EMT. By manipulating the levels of PrPC in different EGFR-mutated NSCLC cell lines, we firmly establish that the expression of PrPC is mandatory for cells to maintain or acquire a mesenchymal phenotype. Mechanistically, we show that PrPC operates through an ILK-RBPJ cascade, which also controls the expression of EGFR. Our data further demonstrate that PrPC levels are elevated in EGFR-mutated versus wild-type tumours or upon EGFR activation in vitro. In addition, we provide evidence that PRNP levels increase with TKI resistance and that reducing PRNP expression sensitizes cells to osimertinib. Finally, we found that plasma PrPC levels are increased in EGFR-mutated NSCLC patients from 2 independent cohorts and that their longitudinal evolution mirrors that of disease. Altogether, these findings define PrPC as a candidate driver of EMT-dependent resistance to EGFR-TKI in NSCLC. They further suggest that monitoring plasma PrPC levels may represent a valuable non-invasive strategy for patient follow-up and warrant considering PrPC-targeted therapies for EGFR-mutated NSCLC patients with TKI failure.

Real-world analysis of survival outcomes in advanced EGFR-mutant NSCLC patients treated with platinum-pemetrexed after EGFR-TKI treatment failure

EGFR tyrosine kinase inhibitors (TKIs) are the standard therapy for non-small-cell lung cancer (NSCLC) patients with EGFR-activating mutations in the first-line setting. Despite initial efficacy, resistance to EGFR-TKIs often develops, and platinum-based chemotherapy is the predominant subsequent treatment. For this study, we aimed to identify prognostic factors for overall survival (OS) and progression-free survival (PFS) among advanced EGFR-mutant NSCLC patients receiving platinum-pemetrexed after progression on EGFR-TKIs. Our analysis specifically focuses on 1st-line treatments limited to 1st- or 2nd-generation EGFR-TKIs, while not restricting later-line treatments involving osimertinib prior to chemotherapy. From 2012 to 2017, 363 patients who received first-line treatment with first- or second-generation EGFR-TKIs, including gefitinib, erlotinib, and afatinib were enrolled. Some patients received different EGFR-TKIs, including osimertinib, as later-line treatment before platinum-pemetrexed. Median OS from the initiation of platinum-pemetrexed was 22.0 months and median PFS with platinum-pemetrexed was 6.2 months. In the multivariate Cox model, we identified three independent prognostic factors for better OS: postoperative recurrence (HR: 0.34, p=0.004), first-line EGFR-TKI PFS ≥12 months (HR: 0.54, p=0.002), and osimertinib treatment after platinum-pemetrexed (HR: 0.56, p=0.005) while BMI <18.5 indicated poor prognosis (HR:1.76, p=0.049). No statistically significant independent prognostic factors for PFS were found. Receiving osimertinib before platinum-pemetrexed treatment did not impact PFS with platinum-pemetrexed treatment (HR: 1.11, p=0.64). Postoperative recurrence, first-line EGFR-TKI PFS ≥12 months and osimertinib treatment after platinum-pemetrexed predicted better OS, while BMI <18.5 predicted worse OS. Osimertinib treatment before platinum-pemetrexed treatment did not affect the efficacy of platinum-pemetrexed.

Real-world outcomes of atypical EGFR-mutated metastatic non-small cell lung cancer (mNSCLC) treated with osimertinib (osi) vs. Afatinib or erlotinib

ObjectivesLimited data are available comparing the efficacy of osi versus earlier generation TKIs for mNSCLC with atypical EGFR mutations (AMs) such as L861Q, G719X, S768I and exon20. MethodsWe performed a single-institution retrospective analysis of patients with EGFR-mutated mNSCLC treated from 2007 to 2023 with 1L TKIs, comparing outcomes for AM patients treated with osi, afatinib, and erlotinib. Baseline demographics, disease characteristics, treatment history, toxicity, and clinical outcomes were abstracted from the electronic medical record and compared between TKIs using independent sample t-tests and chi-square analyses. Median progression free survival (mPFS) and overall survival (mOS) were compared via Kaplan-Meier log-rank analysis and Cox multivariable regression. ResultsAmong 355 patients with EGFR-mutated mNSCLC, 36 (10 %) harbored AMs in G719X (N=21; 6 %), Exon 20 (N=11; 3 %), L861Q (N=7; 2 %), S768I (N=4; 1 %), C797S (N=1; 0.3 %); 6 patients had compound mutations. Patients with classical mutations (CMs) vs AMs had similar baseline demographic and disease characteristics and usage of TKIs (p = 0.124). Among AM patients, osi yielded superior mPFS (22 m) vs afatinib (12 m; p = 0.005) or erlotinib (9 m; p = 0.001). mOS was likewise superior for osi (32 m) vs afatinib (21 m; p = 0.032) or erlotinib (17 m; p = 0.011). Dose-reduction rates due to AEs were lower for osi (19 %) vs afatinib (24 %; p = 0.003) or erlotinib (23 %; p = 0.002). Discontinuation rates due to AEs were lower for osi vs afatinib (1 % vs 2 %; p < 0.001) or erlotinib (2 %; p = 0.004). ConclusionsIn a large real-world analysis, osi demonstrated superior progression-free and overall survival and improved tolerability compared to afatinib or erlotinib for atypical EGFR-mutated mNSCLC.

PIKing up and AKTing on Resistance Mutations in Osimertinib-Treated EGFR-Mutated NSCLC.

A recent study identified high rates of PI3K-AKT pathway mutations from the FLAURA and AURA3 osimertinib trials and pre-clinically validated that these mutations decreased osimertinib sensitivity in EGFR-mutated non-small cell lung cancer. The AKT inhibitor capivasertib was found to overcome this resistance, providing an important rationale for the development of AKT inhibitors in non-small cell lung cancer. See related article by Grazini et al., p. 4143.

Patient-centric thresholding of Cobas® EGFR mutation Test v2 for surveillance of EGFR-mutated metastatic non-small cell lung cancer

Cobas EGFR mutation Test v2 was FDA-approved as qualitative liquid biopsy for actionable EGFR variants in non-small cell lung cancer (NSCLC). It generates semiquantitative index (SQI) values that correlate with mutant allele levels, but decision thresholds for clinical use in NSCLC surveillance are lacking. We conducted long-term ctDNA monitoring in 20 subjects with EGFR-mutated NSCLC; resulting in a 155 on-treatment samples. We defined optimal SQI intervals to predict/rule-out progression within 12 weeks from sampling and performed orthogonal calibration versus deep-sequencing and digital PCR. SQI showed significant diagnostic power (AUC 0.848, 95% CI 0.782–0.901). SQI below 5 (63% of samples) had 93% (95% CI 87–96%) NPV, while SQI above 10 (25% of samples) had 69% (95% CI 56–80%) PPV. Cobas EGFR showed perfect agreement with sequencing (Kappa 0.860; 95% CI 0.674–1.00) and digital PCR. SQI values strongly (r: 0.910, 95% 0.821–0.956) correlated to mutant allele concentrations with SQI of 5 and 10 corresponding to 6–9 (0.2–0.3%) and 64–105 (1.1–1.6%) mutant allele copies/mL (VAF) respectively. Our dual-threshold classifier of SQI 0/5/10 yielded informative results in 88% of blood draws with high NPV and good overall clinical utility for patient-centric surveillance of metastatic NSCLC.

Combination of radiotherapy and PD-L1 blockade induces abscopal responses in EGFR-mutated lung cancer through activating CD8+ T cells

Patients with EGFR-mutated non-small cell lung cancer (NSCLC) respond poorly to immune checkpoint inhibitors (ICIs). It has been reported that the number of CD8+T cells is reduced in EGFR-mutated NSCLC. However, the extent of heterogeneity and effector function of distinct populations of CD8+T cells has not been investigated intensively. In addition, studies investigating whether a combination of radiotherapy and ICIs can improve the efficacy of ICIs in EGFR-mutated lung cancer are lacking. Single-cell RNA sequencing (scRNA-seq) was used to investigate the heterogeneity of CD8+T cell populations in EGFR-mutated NSCLC. The STING pathway was explored after hypofractionated radiation of EGFR-mutated and wild-type cells. Mice bearing LLC-19del and LLC-EGFR tumors were treated with radiotherapy plus anti-PD-L1. The scRNA-seq data showed the percentage of progenitor exhausted CD8+T cells was lower in EGFR-mutated NSCLC. In addition, CD8+T cells in EGFR-mutated NSCLC were enriched in oxidative phosphorylation. In EGFR-mutated and wild-type cells, 8 Gy × 3 increased the expression of chemokines that recruit T cells and activate the cGAS-STING pathway. In the LLC-19del and LLC-EGFR mouse model, the combination of radiation and anti-PD-L1 significantly inhibited the growth of abscopal tumors. The enhanced abscopal effect was associated with systemic CD8+T cell infiltration. This study provided an intensive understanding of the heterogeneity and effector functions of CD8+T cells in EGFR-mutated NSCLC. We showed that the combination of hypofractionated radiation and anti-PD-L1 significantly enhanced the abscopal responses in both EGFR-mutated and wild-type lung cancer by activating CD8+T cells in mice.

Cost-effectiveness analysis of osimertinib plus chemotherapy for patients with EGFR-mutated advanced non-small cell lung cancer.

First-line osimertinib plus chemotherapy significantly prolonged progression-free survival of patients with EGFR-mutated advanced non-small cell lung cancer (NSCLC) compared to osimertinib, according to the FLAURA2 trial. We established a Markov model to compare the cost-effectiveness of osimertinib plus chemotherapy with that of osimertinib alone. Clinical data were obtained from the FLAURA and FLAURA2 trials, and additional data were extracted from online resources and publications. Sensitivity analyses were conducted to evaluate the robustness of the findings. We used A willingness-to-pay threshold of $150,000 per quality-adjusted life-years (QALYs) gained. The main outcomes were QALYs, overall costs, incremental cost-effectiveness ratio (ICER), incremental net monetary benefit, and incremental net health benefit. Subgroup analyses were conducted according to patients' mutation type and central nervous system (CNS) metastatic status. In a 20-year time horizon, the ICER of osimertinib plus chemotherapy versus osimertinib alone was $223,727.1 per QALY gained. The sensitivity analyses identified the cost of osimertinib and the hazard ratio for overall survival as the top 2 influential factors and a 1.9% probability of osimertinib plus chemotherapy to be cost-effective. The subgroup analyses revealed ICERs of $132,614.1, $224,449.8, $201,464.1, and $130,159.7 per QALY gained for L858R mutations, exon 19 deletions, CNS metastases, and no CNS metastases subgroups, respectively. From the perspective of the United States health care system, osimertinib plus chemotherapy is not cost-effective compared to osimertinib alone for treatment-naïve patients with EGFR-mutated advanced NSCLC, but more favorable cost-effectiveness occurs in patients with L858R mutations and patients without baseline CNS metastases.

Landscape of Concomitant Driver Alterations in Classical EGFR-Mutated Non-Small Cell Lung Cancer.

Next-generation sequencing (NGS) has enabled the detection of concomitant driver alterations in non-small cell lung cancer (NSCLC). However, the magnitude and clinical relevance of concomitant drivers remain to be explored. We profiled concomitant driver alterations of EGFR+ NSCLC by using targeted NGS. The associated genomic and clinical features were analyzed and validated in an independent The Cancer Genome Atlas cohort of patients with EGFR+ NSCLC. Out of the total patient population, 334 patients had EGFR mutations along with concomitant driver mutations, comprising 3.09% of the entire cohort. The most frequent co-occurring mutations with sensitizing EGFR mutations include KRAS at 53.9%, followed by ERBB2 at 24.3%, MET at 16.5%, and BRAF at 3.3%. KRAS mutations in concomitant drivers were frequently hyperexchange mutations (25.6% v 8.2%, P < .001), compared with KRAS single drivers. EGFR/ERBB2 drivers exhibited a higher incidence of ERBB2 amplification (40.7% v 16.5%, P < .001) and p.S310F/Y mutations (44.4% v 4.3%, P < .001) compared with ERBB2 alone. EGFR/MET drivers had a higher frequency of MET amplification (71.4% v 43.3%) than MET single drivers. At the genomic level, the median number of additional concurrent mutations was four, with TSC2 (4%), CD274 (1%), and TP53 (63%) being the most frequently coaltered genes in concomitant driver tumors. Interestingly, clonality analysis indicated that EGFR mutations were more likely to occur as clonal events, whereas the codrivers were more often subclonal. Patients with concomitant drivers or with concomitant MET amplification exhibited worse prognosis. These findings might aid in the selection of effective therapeutic regimens and facilitate the development of combination therapies.

Afatinib plus PEM and CBDCA overcome osimertinib resistance in EGFR-mutated NSCLC with high thrombospondin-1 expression.

Osimertinib induces a marked response in non-small-cell lung cancer (NSCLC) patients harboring epidermal growth factor receptor (EGFR) gene mutations. However, acquired resistance to osimertinib remains an inevitable problem. In this study, we aimed to investigate osimertinib-resistant mechanisms and evaluate the combination therapy of afatinib and chemotherapy. We established osimertinib-resistant cell lines (PC-9-OR and H1975-OR) from EGFR-mutant lung adenocarcinoma cell lines PC-9 and H1975 by high exposure and stepwise method. Combination therapy of afatinib plus carboplatin (CBDCA) and pemetrexed (PEM) was effective in both parental and osimertinib-resistant cells. We found that expression of thrombospondin-1 (TSP-1) was upregulated in resistant cells using cDNA microarray analysis. We demonstrated that TSP-1 increases the expression of matrix metalloproteinases through integrin signaling and promotes tumor invasion in both PC-9-OR and H1975-OR, and that epithelial-to-mesenchymal transition (EMT) was involved in H1975-OR. Afatinib plus CBDCA and PEM reversed TSP-1-induced invasion ability and EMT changes in resistant cells. In PC-9-OR xenograft mouse models (five female Balb/c-Nude mice in each group), combination therapy strongly inhibited tumor growth compared with afatinib monotherapy (5 mg/kg, orally, five times per week) or CBDCA (75 mg/kg, intraperitoneally, one time per week) + PEM (100 mg/kg, intraperitoneally, one time per week) over a 28-day period. These results suggest that the combination of afatinib plus CBDCA and PEM, which effectively suppresses TSP-1 expression, may be a promising option in EGFR-mutated NSCLC patients after the acquisition of osimertinib resistance.

The efficacy of almonertinib and anlotinib combination therapy for advanced non-small-cell lung cancer patients who continued to experience cancer progression during third-generation EGFR-TKI treatment: a retrospective study.

Epidermal growth factor receptor (EGFR) mutations are key drivers in a significant portion of non-small-cell lung cancer (NSCLC) patients. While third-generation EGFR-tyrosine kinase inhibitors (TKIs) such as osimertinib have demonstrated efficacy, the management of patients who continue to experience disease progression during treatment remains challenging. The emergence of drug resistance, including the development of secondary mutations, necessitates exploration of alternative treatment strategies. This study aims to evaluate and observe the efficacy and safety of almonertinib combined with anlotinib in patients after cancer progression during third-generation EGFR-TKI therapy. In this retrospective analysis, we included EGFR-mutated NSCLC patients who were resistant to third-generation EGFR-TKIs. All patients were treated with almonertinib combined with anlotinib. The clinical characteristics, treatment history, clinical benefits, and adverse events of these patients were retrospectively collected. A total of 16 eligible patients were included in the analysis. The results revealed that combination therapy with almonertinib and anlotinib was effective in this patient cohort. The overall response rate was 25% and the disease control rate was 93.75%. The 6 and 12 months of PFS rates were 92.9% (95% confidence interval [CI] 80.3%, 100.0%) and 84.4% (95% CI 66.6%, 100.0%), respectively. Moreover, this combination therapy was generally well-tolerated, with manageable adverse events. Our retrospective analysis suggests that almonertinib and anlotinib combination therapy may represent a viable option for EGFR-mutated NSCLC patients who have progressed on third-generation EGFR-TKIs, especially for those with posterior lines and no standard treatment options. Further investigation and larger clinical trials are warranted to validate these observations and refine treatment guidelines.

METTL14-mediated Bim mRNA m6A modification augments osimertinib sensitivity in EGFR-mutant NSCLC cells.

Resistance to osimertinib represents a significant challenge for the successful treatment of non-small cell lung cancer (NSCLC) harboring activating mutations in epidermal growth factor receptor (EGFR). N6-methyladenosine (m6A) on mRNAs is critical for various biological processes, yet whether m6A regulates osimertinib resistance of NSCLC remains unknown. In this study, we demonstrated that developing osimertinib-resistant phenotypes depends on m6A reduction resulting from downexpression of m6A methyltransferase METTL14 in EGFR-mutant NSCLCs. Both in vitro and in vivo assay showed that specific knockdown of METTL14 was sufficient to confer osimertinib resistance and elevated expression of METTL14 rescued the efficacy of osimertinib in the resistant NSCLC cells. Mechanistically, METTL14 promoted m6A methylation of pro-apoptotic Bim mRNA and increased Bim mRNA stability and expression, resulting in activating the Bim-dependent pro-apoptotic signaling and thereby promoting osimertinib-induced cell apoptosis. Analysis of clinical samples revealed that decreased expression of METTL14 was observed in osimertinib-resistant NSCLC tissues and significantly associated with a poor prognosis. In conclusion, our study reveals a novel regulatory mechanism by which METTL14-mediated m6A methylation of Bim mRNA inhibited osimertinib resistance of NSCLC cells. It offers more evidences for the involvement of m6A modification in regulation of osimertinib resistance, and provides potential therapeutic targets for novel approaches to overcome the tolerance of osimertinib and other EGFR-TKIs. Implications: This study offers more evidences for the involvement of METTL14-mediated m6A modification in regulation of osimertinib resistance, and provides potential therapeutic targets for novel approaches to overcome the tolerance of osimertinib and other EGFR-TKIs.