Epidermal Growth Factor Receptor L858R Mutation Research Articles

Abstract LB056: IBI334, a novel ADCC-enhanced B7-H3/EGFR bispecific antibody, demonstrated potent pre-clinical efficacy in solid tumors

Abstract Many solid tumors, such as colorectal cancer (CRC) and lung cancer, are dependent on epidermal growth factor receptor (EGFR) pathway for tumor growth. Antibodies that inhibit EGFR signaling, such as Cetuximab, show clinical efficacy but are associated with on-target toxicities that potentially limit the drug efficacy. To enhance the EGFR signaling inhibition and reduce on-target toxicities, we performed bioinformatics analysis for EGFR/TAA co-expression. We found that B7-H3, a member of the B7 family of immune checkpoint proteins, is broadly expressed in many solid tumors and their expression correlates with EGFR expression in multiple cancers, including lung cancer, head and neck cancer, pancreatic cancer and esophageal cancer. Using Innovent’s proprietary Innobody platform, we developed a bispecific antibody, IBI334, against B7-H3 and EGFR. IBI334 has an EGFR arm for signal blockage and is coupled with a fine-tuned B7-H3 arm with optimal affinity and binding domain. With the aid of B7-H3, IBI334 showed enhanced EGFR signal inhibition than Zalutumumab (EGFR mAb) and Amivantamab (c-met/EGFR bsAb). In addition, IBI334 is afucosylated to enhance its antibody-mediated cell cytotoxicity (ADCC) effects as compared to wild type antibody. IBI334 showed significantly better in vivo efficacy than Amivantamab in NCI-H358 (bronchioalveolar carcinoma with KRAS-G12C mutation), NCI-H292 (lymph node metastasis of a pulmonary mucoepidermoid carcinoma), SK-MES1 (lung cancer) and SK-MES1-LTC (lung cancer with EGFR L858R, T790M and C797S mutations) xenograft models and comparable efficacy in NCI-H322-EGFRexon20ins (lung cancer) model. Cetuximab, an EGFR monoclonal antibody, had high on-target toxicity with 50% early mortalities in cynomolgus monkeys at 120/75 mg/kg/week. With the careful design of B7-H3/EGFR bispecific antibody, IBI334 ameliorated the on-target toxicities and showed only slight hardening of the skin at the injection site at 120 mg/kg/week. As a result, IBI334 has a large therapeutic window of >200 folds. In conclusion, IBI334 is a potent B7-H3/EGFR bispecific antibody with broad application in many EGFR-driven solid tumors. The large therapeutic window enables safe and effective cancer treatment at high exposure levels. Citation Format: Jian Guan, Shuaixiang Zhou, Weiwei Wu, Tianyu Zhu, Lei Cao, Ming Wu, Ninghuan Li, Fenggen Fu, Zhengguan Liao, Shuming Lin, Zeyu Liu, Mengjia Zhu, Nana Luo, Ying Zhang, Tiong Sun Chia, Bingliang Chen, Kaijie He. IBI334, a novel ADCC-enhanced B7-H3/EGFR bispecific antibody, demonstrated potent pre-clinical efficacy in solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB056.

MET overexpression correlated with prognosis of EGFR-mutant treatment‑naïve advanced lung adenocarcinoma: a real‑world retrospective study.

About 50-60% treatment-naïve advanced non-small-cell lung cancers were coexistence of epidermal growth factor receptor (EGFR) and mesenchymal epithelial transition (MET) overexpression. However, few studies demonstrated the prognostic value of MET protein expression in untreated EGFR-mutant lung adenocarcinoma (LUAD). A total of 235 EGFR-mutant untreated advanced LUAD patients were retrospectively enrolled. MET expression was determined using immunohistochemistry, and MET positivity was defined as 2 + or 3 + using the METmab scoring algorithm. Progression-free survival (PFS) and overall survival (OS) were analysed according to MET expression status. Independent factors predicting prognosis were identified using multivariate Cox regression analyses. Of the 235 patients, 113 (48.1%) harboured exon 19 deletion (19_del), 103 (43.8%) had exon 21 L858R mutations, and 19 (8.1%) had other mutation types, including exon 21 L861Q, exon 18 G719A/C, exon 20 S768I, and L858R/19_del double mutations. MET-positive expression was observed in 192 (81.7%) cases. There was no significant difference in baseline clinicopathological characteristics between MET positivity and MET negativity groups. Patients were stratified by different EGFR mutation subtypes. MET-positive patients in the L858R mutation subgroup had markedly shorter PFS and OS than MET-negative patients (median PFS: 13 versus 27.5months, p < 0.001; median OS: 29 versus not reached, p = 0.008), but no significant difference was observed in the 19_del subgroup. Multivariate Cox regression analyses indicated that MET positivity was an independent predictor for poor PFS and OS in L858R subgroup (PFS: HR = 3.059, 95% CI 1.552-6.029, p = 0.001; OS: HR = 3.511, 95% CI 1.346-9.160, p = 0.010). Additionally, an inferior survival outcome of MET positivity was observed in the L858R mutation subgroup when treated with EGFR-tyrosine kinase inhibitor (TKI) monotherapy as the first-line regimen (median PFS: 13 versus 36.5months, p < 0.001; median OS: 29 versus not reached, p = 0.012) but not with EGFR-TKI plus platinum doublet chemotherapy. MET positive expression was an independent predictor of poor outcomes in untreated EGFR L858R mutation advanced LUAD patients treated with first-line EGFR-TKI monotherapy.

Genetic mutation profiling reveals biomarkers for targeted therapy efficacy and prognosis in non-small cell lung cancer

IntroductionThe genetic heterogeneity of non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations may affect clinical responses and outcomes to EGFR tyrosine kinase inhibitors (EGFR-TKIs). This study aims to investigate the genomic factors that influence the efficacy and clinical outcomes of first-line, second-line and third-line treatments in NSCLC and explore the heterogeneity of resistance mechanisms. Materials and methodsThis real-world study comprised 65 patients with EGFR mutant NSCLC. Molecular alterations were detected using a customized DNA panel before and after administering targeted therapy. The efficacy and prognosis of each treatment line were evaluated. ResultsIn first-generation EGFR-TKIs treatment, gefitinib showed favorable efficacy compared to icotinib and erlotinib, particularly in patients with EGFR L858R mutations. The resistance mechanisms to first-generation EGFR-TKIs varied among different EGFR mutation cohorts and different first-generation EGFR-TKIs. In second-line EGFR-TKIs treatment, EPH receptor A3 (EPHA3), IKAROS family zinc finger 1 (IKZF1), p21 (RAC1) activated kinase 5 (PAK5), DNA polymerase epsilon, catalytic subunit (POLE), RAD21 cohesin complex component (RAD21) and RNA binding motif protein 10 (RBM10) mutations were markedly associated with poorer progression-free survival (PFS). Notably, EPHA3, IKZF1 and RBM10 were identified as independent predictors of PFS. The mechanisms of osimertinib resistance exhibited heterogeneity, with a higher proportion of non-EGFR-dependent resistant mutations. In third-line treatments, the combination of osimertinib and anlotinib demonstrated superior efficacy compared to other regimens. Glutamate ionotropic receptor NMDA type subunit 2A (GRIN2A) mutation was an independent risk indicator of shorter OS following third-line treatments. ConclusionsComprehending the tumor evolution in NSCLC is advantageous for assessing the efficacy and prognosis at each stage of treatment, providing valuable insights to guide personalized treatment decisions for patients.

MscI restriction enzyme cooperating recombinase-aided isothermal amplification for the ultrasensitive and rapid detection of low-abundance EGFR mutations on microfluidic chip

The detection of low-abundance mutation genes of the epidermal growth factor receptor (EGFR) exon 21 (EGFR L858R) plays a crucial role in the diagnosis of non-small cell lung cancer (NSCLC), as it enables early cancer detection and facilitates the development of treatment strategies. A detection platform was developed by combining the MscI restriction enzyme with the recombinase-aided isothermal amplification (RAA) technique (MRE-RAA). During the RAA process, “TGG^CCA” site of the wild-type genes was cleaved by the MscI restriction enzyme, while only the low-abundance mutation genes underwent amplification. Notably, when the RAA product was combined with CRISPR-Cas system, the sensitivity of detecting the EGFR L858R mutation increased by up to 1000-fold for addition of the MscI restriction enzyme. This achievement marked the first instance of attaining an analytical sensitivity of 0.001%. Furthermore, a disk-shaped microfluidic chip was developed to automate pretreatment while concurrently analyzing four blood samples. The microfluidic features of the chip include DNA extraction, MRE-RAA, and CRISPR-based detection. The fluorescence signal is employed for detection in the microfluidic chip, which is visible to the naked eye upon exposure to blue light irradiation. Furthermore, this platform has the capability to facilitate early diagnosis for various types of cancer by enabling high-sensitivity detection of low-abundance mutation genes.

Brain metastasis, EGFR mutation subtype and generation of EGFR-TKI jointly influence the treatment outcome of patient with EGFR-mutant NSCLC

Non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutation is brain metastasis (BM)-prone. We determined the impact of this hallmark, along with EGFR subtype and generation of tyrosine kinase inhibitor (TKI) treatment, on patients’ outcome. 553 metastatic EGFR-mutant NSCLC patients received front-line EGFR-TKI treatment. Progression-free survival (PFS), overall survival (OS) and secondary T790M rate were analysed. BM was observed in 211 (38.2%) patients. BM (HR 1.20 [95% CI 0.99–1.48]; p = 0.053), ECOG PS 0–1 (HR 0.71 [95% CI 0.54–0.93]; p = 0.014) and afatinib treatment (HR 0.81 [95% CI 0.66–0.99]; p = 0.045) were associated with PFS. Afatinib-treated patients without BM demonstrated a significantly longer PFS (16.3 months) compared to afatinib-treated patients with BM (13.7 months) and to gefitinib/erlotinib-treated patients with (11.1 months) or without BM (14.2 months; p < 0.001). CNS-only progression trended higher in afatinib-treated patients. ECOG PS 0–1 (HR 0.41 [95% CI 0.31–0.56]; p < 0.001) and EGFR L858R mutation (HR 1.46 [95% CI 1.13–1.88]; p = 0.003), but not BM, were the predictors for OS. BM (OR 2.02 [95% CI 1.02–4.08]; p = 0.040), afatinib treatment (OR 0.26 [95% CI 0.12–0.50]; p < 0.001) and EGFR L858R mutation (OR 0.55 [95% CI 0.28–1.05]; p = 0.070) were associated with secondary T790M rate. In BM patients, gefitinib/erlotinib-treated ones with 19 deletion mutation and afatinib-treated ones with L858R mutation had the highest and the lowest T790M rate (94.4% vs. 27.3%, p < 0.001), respectively. BM and generation of EGFR-TKI jointly impact PFS and secondary T790M rate in patients with EGFR-mutant NSCLC, whereas OS was mainly associated with EGFR subtype.

Tissue and Plasma-Based Highly Sensitive Blocker Displacement Amplicon Nanopore Sequencing for EGFR Mutations in Lung Cancer.

The epidermal growth factor receptor (EGFR) mutation is a widely prevalent oncogene driver in non-small cell lung cancer (NSCLC) in East Asia. The detection of EGFR mutations is a standard biomarker test performed routinely in patients with NSCLC for the selection of targeted therapy. Here, our objective was to develop a portable new technique for detecting EGFR (19Del, T790M, and L858R) mutations based on Nanopore sequencing. The assay employed a blocker displacement amplification (BDA)-based polymerase chain reaction (PCR) technique combined with Nanopore sequencing to detect EGFR mutations. Mutant and wild-type EGFR clones were generated from DNA from H1650 (19Del heterozygous) and H1975 (T790M and L858R heterozygous) lung cancer cell lines. Then, they were mixed to assess the performance of this technique for detecting low variant allele frequencies (VAFs). Subsequently, formalin-fixed, paraffin-embedded (FFPE) tissue and cell-free DNA (cfDNA) from patients with NSCLC were used for clinical validation. The assay can detect low VAF at 0.5% mutant mixed in wild-type EGFR. Using FFPE DNA, the concordance rates of EGFR 19Del, T790M, and L858R mutations between our method and Cobas real-time PCR were 98.46%, 100%, and 100%, respectively. For cfDNA, the concordance rates of EGFR 19Del, T790M, and L858R mutations between our method and droplet digital PCR were 94.74%, 100%, and 100%, respectively. The BDA amplicon Nanopore sequencing is a highly accurate and sensitive method for the detection of EGFR mutations in clinical specimens.

Do patient characteristics affect EGFR tyrosine kinase inhibitor treatment outcomes? A network meta-analysis of real-world survival outcomes of East Asian patients with advanced non-small cell lung cancer treated with first-line EGFR-TKIs.

Despite the well-established efficacies of tyrosine kinase inhibitors (TKIs) in epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC), there is limited real-world evidence comparing their effectiveness according to patients' clinical characteristics. This network meta-analysis (NMA) compared survival outcomes among first-line EGFR-TKIs in different subgroups of East Asian patients with advanced NSCLC. This NMA included real-world observational studies reporting outcomes with TKIs in patients aged >65 years, with baseline brain metastasis, with different Eastern Cooperative Oncology Group (ECOG) statuses, or with different common EGFR mutation types. In patients with the EGFR L858R mutation, afatinib resulted in significantly longer progression-free survival (PFS) than erlotinib (hazard ratio [HR]: 0.59, 95% confidence interval [CI]: 0.46-0.75) and gefitinib (HR: 0.41, 95% CI: 0.32-0.53). Similarly, in patients with the EGFR Del19 mutation, afatinib and erlotinib resulted in significantly longer PFS than gefitinib (HR: 0.48 with 95% CI: 0.33-0.71 and HR: 0.54 with 95% CI: 0.36-0.80, respectively). Moreover, afatinib resulted in significantly longer PFS than gefitinib in patients with brain metastasis (HR: 0.53, 95% CI: 0.33-0.87) or ECOG status 0-1 (HR: 0.37, 95% CI: 0.23-0.59). This NMA suggests that afatinib results in similar PFS to erlotinib and superior PFS than gefitinib in patients with Del19 mutant NSCLC, aged ≥65 years, with ECOG scores of 0-1, and with baseline brain metastasis.

Effects of concurrent TP53 mutations on the efficacy and prognosis of targeted therapy for advanced EGFR mutant lung adenocarcinoma

BackgroundHow concurrent TP53 mutations affect targeted therapy of advanced Epidermal Growth Factor Receptor (EGFR) mutant lung adenocarcinoma remains controversial, particularly the deep classification of TP53 mutations. MethodsThis study retrospectively analyzed the clinical data of advanced EGFR mutant lung adenocarcinoma patients treated with EGFR-tyrosine kinase inhibitors (TKIs) in the First Affiliated Hospital of Soochow University. The survival rates were compared using Log-rank tests. Potential prognostic factors were identified using multivariate Cox hazard regression models. ResultsTotal 156 advanced lung adenocarcinoma patients treated with EGFR-TKIs were included in this study. Multivariate analysis showed that male [hazard rate (HR): 1.537, 95% confidence interval (CI): 1.055–2.240, P = 0.025], brain metastasis (HR: 1.707, 95%CI: 1.086–2.682, P = 0.020) and concurrent TP53 mutations (HR: 1.569, 95%CI: 1.051–2.341, P = 0.028) were independent negative predictors of progression-free survival (PFS). EGFR L858R mutations (HR: 2.475, 95%CI: 1.443–4.248, p = 0.001), smoking history (HR: 2.530, 95%CI: 1.352–4.733, P = 0.004) and concurrent TP53 mutations (HR: 2.326, 95%CI: 1.283–4.218, P = 0.005) were associated with worse survival. Further analysis revealed that mutations in TP53 exons 4, 5 and 8 (P<0.05), missense mutations (P = 0.006) and nondisruptive mutations (P<0.001) were associated with shorter PFS, whereas mutations in TP53 exons 5 and 7 (P<0.05), missense mutations and non-missense mutations (P = 0.006; P = 0.007), disruptive mutations and nondisruptive mutations (P = 0.013; P = 0.013) were all associated with poorer survival times. In addition, the PFS and overall survival (OS) of nondisruptive mutations in exon 7 were worse than those in other exons (P = 0.041; P<0.001). ConclusionsConcurrent TP53 mutations conferred worse EGFR-TKIs efficacy and prognosis in advanced EGFR mutant lung adenocarcinoma and the effects of different TP53 mutation types were heterogeneous.

Effect of bevacizumab plus double dose icotinib on advanced non-small cell lung cancer with EGFR L858R mutation.

e21020 Background: Double-dose icotinib has been proven effective and well tolerated for advanced NSCLC patients with the Epidermal Growth Factor Receptor (EGFR) L858R mutation. For the same patients, the excellent efficacy of bevacizumab combined with erlotinib has been proven in previous studies. In this study, we would investigate the efficacy of the combined therapy bevacizumab and double-dose icotinib for advanced NSCLC patients with EGFR L858R mutation. Methods: 35 patients diagnosed from September 2, 2021 to September 28, 2022 were enrolled in this study and 5 patients were excluded for analysis due to missing efficacy evaluation data. All patients were treated with intravenous bevacizumab (15mg / kg) combined with oral double-dose icotinib (250mg, tid). The primary endpoint was progression-free survival (PFS), and the secondary endpoints were safety, efficacy, and overall survival (OS). Results: Among the 35 patients, 12 were male and 23 were female. The median age at diagnosis was 66. Eight patients were diagnosed with brain metastases. All of the patients have EGFR L858R mutation, and 14 patients were with other coexisting mutations. To the data of December 31, 2022, the median follow-up time was 10 months (range: 3 to 18 months). For 30 patients with complete efficacy evaluation data, 20 patients achieved partial responses (PR), 9 patients had stable disease (SD), and 1 patient developed progress disease (PD). The objective response rate (ORR) was 66.7%, the disease control rate (DCR) was 96.7%, and the median PFS was 14.8 months. For adverse reaction evaluation, the grade 3 adverse events were albuminuria (n = 1) and hepatotoxicity (n = 1). Other adverse events were grade 1-2, mainly oral mucositis, rash, diarrhea and hypertension. Conclusions: The combination of bevacizumab with double-dose icotinib is an effective and relatively safe treatment for advanced NSCLC patients with EGFR L858R mutation. Further exploration will provide more evidence for this type of treatment. Clinical trial information: NCT05263947 .

Osimertinib combined with bevacizumab as the first-line treatment in non-small cell lung cancer patients with brain metastasis harboring epidermal growth factor receptor mutations.

The efficacy and safety of osimertinib combined with bevacizumab in non-small cell lung cancer (NSCLC) patients with brain metastasis harboring epidermal growth factor receptor (EGFR) mutations have not been fully studied. Treatment-naïve NSCLC patients with brain metastasis harboring EGFR-activating mutations were treated with osimertinib 80 mg oral daily and bevacizumab 15 mg/kg intravenously on day 1, repeated every 21 days, until disease progression, intolerable toxicity, or death. The primary endpoint was the median progression-free survival (mPFS), and the secondary endpoints were the median overall survival (mOS), response rates, and toxicities. This study has been registered in ClinicalTrials.gov (NCT05104281) and is ongoing. A total of 52 Chinese patients were enrolled, of whom 17 harbored EGFR 19 del and 35 harbored EGFR L858R mutation. The objective response rate (ORR) was 75.0% and the disease control rate (DCR) was 96.2%; the mPFS was 17.0 months (95% CI: 11.46-22.54), while the mOS was not reached. The mPFS was 20.0 months (95% CI: 14.56-25.44) and was 17.0 months (95% CI: 13.28-20.72) for patients harboring EGFR 19 del and EGFR L858R mutation (p = 0.844), respectively. The intracranial ORR was 82.7%, and the intracranial mPFS was 22.0 months (95% CI: 2.92-41.08).The main adverse events were mild-to-moderate hand-foot syndrome, diarrhea, hypertension, and proteinuria. Three patients developed grade III proteinuria, while five patients developed grade III hypertension; they permanently discontinued bevacizumab treatment. Osimertinib combined with bevacizumab shows promising results in EGFR-mutated NSCLC patients with brain metastasis, and the side effects are tolerable.

Precision immunointerception of EGFR-driven tumorigenesis for lung cancer prevention.

Epidermal growth factor receptor (EGFR) mutations occur in about 50% of lung adenocarcinomas in Asia and about 15% in the US. EGFR mutation-specific inhibitors have been developed and made significant contributions to controlling EGFR mutated non-small cell lung cancer. However, resistance frequently develops within 1 to 2 years due to acquired mutations. No effective approaches that target mutant EGFR have been developed to treat relapse following tyrosine kinase inhibitor (TKI) treatment. Vaccination against mutant EGFR is one area of active exploration. In this study, we identified immunogenic epitopes for the common EGFR mutations in humans and formulated a multi-peptide vaccine (Emut Vax) targeting the EGFR L858R, T790M, and Del19 mutations. The efficacy of the Emut Vax was evaluated in both syngeneic and genetic engineered EGFR mutation-driven murine lung tumor models with prophylactic settings, where the vaccinations were given before the onset of the tumor induction. The multi-peptide Emut Vax effectively prevented the onset of EGFR mutation-driven lung tumorigenesis in both syngeneic and genetically engineered mouse models (GEMMs). Flow cytometry and single-cell RNA sequencing were conducted to investigate the impact of Emut Vax on immune modulation. Emut Vax significantly enhanced Th1 responses in the tumor microenvironment and decreased suppressive Tregs to enhance anti-tumor efficacy. Our results show that multi-peptide Emut Vax is effective in preventing common EGFR mutation-driven lung tumorigenesis, and the vaccine elicits broad immune responses that are not limited to anti-tumor Th1 response.

Detection of EGFR gene with a droplet digital PCR chip integrating a double-layer glass reservoir

The lack of reliable and practical method for detecting rare hot mutation of epidermal growth factor receptor (EGFR) in circulating tumor DNA (ctDNA) for lung cancer has remained a challenge for general clinical application due to excess wild type DNA in clinical samples. In this study, we developed a droplet digital PCR (ddPCR) platform, integrating a PDMS chip and double-layer glass reservoir. The duplex T-junction droplet generators in PDMS chip can produce about one million uniform droplets of 4.187 pL within ∼10 min, which were then stored in the glass reservoir. The double-layer glass reservoir can protect droplets from evaporation and breaking, solving the problem of instability during thermal-cycling. The quantitative capabilities of the ddPCR chip were evaluated by testing EGFR exon gene 21, with a good linear correlation in the wide range of 101 to 106 copies/μL (R2 = 0.9998). We then demonstrated that the proposed ddPCR device can recognize rare EGFR L858R mutation under a background of 106 copies/μL wild-type DNA at a sensitivity of 0.0001%. Finally, we demonstrated this ddPCR platform could identify low amount of EGFR L858R mutation in ctDNA and CTCs of patients with lung cancer.

The benefit of anti-angiogenic therapy in EGFR exon 21 L858R mutant non-small cell lung cancer patients: a retrospective study

Patients with epidermal growth factor receptor (EGFR) exon 21 L858R substitution benefit less from standard EGFR tyrosine kinase inhibitor (TKI) treatment, and whether anti-angiogenic therapy was beneficial to the EGFR L858R subpopulation was inconclusive. A retrospective study was conducted to investigate the survival benefit and the target characteristics of the anti-angiogenic agent in the EGFR L858R patients in our center, comparing those treated with or without anti-angiogenic therapy (cohort A and cohort B). At the median follow-up time of 31.0 months vs 32.7 months (cohort A vs. B) respectively, Cohort A (n = 58) had a significantly prolonged median OS compared to Cohort B (n = 101) (60.0 months vs.37.0 months, HR 0.51, p = 0.016). Anti-angiogenic therapy significantly prolonged the OS in patients with liver metastases (NA vs.26.0 months, HR 0.17, p = 0.023) comparing to patients without liver metastases (60.0 months vs.37.0 months, HR 0.63, p = 0.129). For brain metastatic patients, anti-angiogenic treatment tended to improve median OS with (65.0 months vs.35.0 months, HR 0.29, p = 0.068) or without brain radiotherapy (73.0 months vs.29.0 months, HR 0.24, p = 0.171). The grade 3 or more adverse events were manageable and consistent with previous studies. Patients with EGFR L858R mutation treated with anti-angiogenic therapy in their course of treatment had a significantly prolonged OS compared to those who had never received an anti-angiogenic agent. Patients with liver metastases might benefit more from anti-angiogenic therapy than those without.

MET overexpression in EGFR L858R mutant treatment-naïve advanced lung adenocarcinoma correlated with poor prognosis: a real-world retrospective study.

Mesenchymal epithelial transition (MET) overexpression has been reported in approximately 50-60% of epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancers. However, the prognostic significance of MET overexpression has not been established in advanced lung adenocarcinoma (ADC) patients with EGFR-sensitive mutations. A retrospective study was performed on a total of 406 treatment-naïve advanced ADC patients with EGFR mutation detection and MET expression information. EGFR mutations were detected by next-generation sequencing or amplification refractory mutation system-polymerase chain reaction. Immuno-histochemistry staining of MET expression was evaluated by H-score and overexpression was defined as an H-score ≥ 200. Overall survival (OS) and progression-free survival (PFS) were analyzed according to MET expression. Among the 406 patients, 208 patients had EGFR mutations, including 102 exon 19_del mutations, 94 L858R mutations and 12 other types of mutations. Of 110 patients with concomitant EGFR mutations and MET overexpression, 61 (59.8%) patients had 19_del mutations, 44 (46.8%) patients had L858R mutations and five (41.7%) patients had others. Patients with MET overexpression had a markedly shorter PFS and OS than patients with MET H-score < 200 in the EGFR L858R mutation subgroup (median PFS: 12 versus 26months, p = 0.001; median OS: 24 versus 32months, p = 0.038), whereas no significant difference was observed in 19_del mutation subgroup. Multivariate Cox analysis showed that MET overexpression was an independent poor prognostic factor for PFS and OS in patients with the L858R mutations (HR = 3.064, 95% CI 1.705-5.507, p < 0.001; HR = 2.043, 95% CI 1.000-4.172; p = 0.049), rather than 19_del. MET overexpression is a poor prognostic factor for advanced ADC patients with the EGFR L858R mutation.

1O Furmonertinib versus gefitinib in treatment-naïve EGFR mutated non-small cell lung cancer: A randomized, double-blind, multi-center, phase III study (FURLONG)

Furmonertinib (AST2818) is an irreversible, selective third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI). This study aimed to compare the efficacy and safety of furmonertinib versus gefitinib in untreated advanced non-small cell lung cancer (NSCLC) patients with EGFR sensitizing mutations. FURLONG was a randomized, double-blind, phase III study conducted in 55 centers across mainland China. Stage IIIB/IIIC/IV NSCLC patients with EGFR Ex19Del or L858R mutation positive were enrolled to receive either furmonertinib 80 mg/d or gefitinib 250 mg/d as first-line therapy. The primary endpoint was progression-free survival (PFS) assessed by an independent review center (IRC). Between May 30, 2019 and Dec 5, 2019, 358 patients were randomized to receive furmonertinib (n=178) or gefitinib (n=180) treatment. In the furmonertinib and gefitinib groups, 35% and 32% had central nervous system (CNS) metastases at baseline, respectively. As of Sep 15 2021, the median follow-up was both 21.0 months in each group. The median PFS with furmonertinib was significantly longer than with gefitinib (20.8 versus 11.1 months; HR 0.44 [95%CI 0.34-0.58]; p<0.0001). The clinical benefit of PFS was consistent across all pre-specified subgroups including patients with CNS metastases (HR 0.50 [95%CI 0.32-0.80]). The median duration of exposure was 18.3 months in the furmonertinib group and 11.2 months in the gefitinib group, whereas the frequency of grade≥3 treatment-related adverse events (TRAEs) was 11% in the furmonertinib group and 18% in the gefitinib group. Furmonertinib significantly prolonged PFS and showed less grade≥3 TRAEs compared with gefitinib as first-line treatment in advanced EGFR mutated NSCLC patients.

Front-Line ICI-Based Combination Therapy Post-TKI Resistance May Improve Survival in NSCLC Patients With EGFR Mutation.

BackgroundData on the use of immune checkpoint inhibitors (ICIs) in advanced non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutation are limited. The current study aimed to assess the efficacy of ICIs in EGFR-mutant advanced NSCLC and explore the relevant influential factors.Materials and MethodsRelevant clinical data of EGFR-mutant NSCLC patients who had received ICIs were collected from multiple hospitals. The primary endpoint was progression-free survival (PFS), and the secondary endpoints were overall survival (OS), objective response rate (ORR), and relevant influential factors.ResultsA total of 122 advanced EGFR-mutant NSCLC patients were included in the final analysis. The total cohort had an objective response rate (ORR) of 32.0%, a median progression-free survival (mPFS) of 5.0 months, and a median overall survival (mOS) of 14.4 months. Among 96 patients with common EGFR mutations (19Del, 52 patients; L858R, 44 patients), those who were administered front-line ICI exhibited better survival benefits than those who received later-line ICI after disease progression on tyrosine kinase inhibitors (TKIs) treatment (mPFS: 7.2 months vs. 3.4 months, respectively, P < 0.0001; mOS: 15.1 months vs. 8.4 months, respectively, P <0.0001). Moreover, the efficacy of ICI-based combination therapy was better than that of ICI monotherapy (mPFS: 5.0 months vs. 2.2 months, respectively, P = 0.002; mOS: 14.4 months vs. 7.0 months, respectively, P = 0.001). Multivariate analysis showed that ICI-based combination therapy and front-line ICI administration after progression on EGFR-TKI were associated with significant improvements in both PFS and OS (P < 0.05). A high PD-L1 expression (tumor proportion score, TPS≥50%) and the EGFR L858R mutation were only significantly associated with a better PFS (P <0.05). A better Eastern Cooperative Oncology Group (ECOG) status was independently associated with a favorable OS (P <0.05).ConclusionsTaken together, combination immunotherapy in front-line was associated with improvement of survival in EGFR-mutant NSCLC patients post-TKI resistance. Further prospective studies with large sample sizes are required to identify the optimal combinatorial treatment strategy.

Differential diagnosis of multiple primary lung cancers and intra-lung metastasis of lung cancer by multiple gene detection.

Differential diagnosis of multiple primary lung cancers and intra-lung metastasis of lung cancer by multiple gene detection.

Value and significance of brain radiation therapy during first-line EGFR-TKI treatment in lung adenocarcinoma with EGFR sensitive mutation and synchronous brain metastasis: Appropriate timing and technique.

BackgroundFor lung adenocarcinoma patients with epidermal growth factor receptor (EGFR) sensitive mutation and synchronous brain metastasis (syn‐BM), when and how to apply radiotherapy (RT) during first‐line tyrosine kinase inhibitor (TKI) treatment remains debatable.MethodsFrom a real‐world multicenter database, EGFR‐mutant patients with syn‐BM diagnosed between 2010–2020 and treated with first‐line TKIs were enrolled and divided into upfront TKI + RT and upfront TKI groups. Median intracranial progression‐free survival (mIC‐PFS), median overall survival (mOS), and their risk factors were estimated.ResultsThere were 60 and 186 patients in the upfront TKI + RT group and upfront TKI group, respectively. Their mIC‐PFS were 28.9 months (m) and 17.5 m (p = 0.023), and mOS were 42.7 m and 40.1 m (p = 0.51). Upfront brain RT improved mIC‐PFS in patients ≤60‐year‐old (p = 0.035), with symptomatic BM (p = 0.002), and treated with first‐generation TKIs (p = 0.012). There was no significant difference in mOS in any subgroup. Upfront brain stereotactic radiosurgery (SRS) showed a trend of better mIC‐PFS and mOS. mIC‐PFS was independently correlated with symptomatic BM (HR = 1.54, p = 0.030), EGFR L858R mutation (HR = 1.57, p = 0.019), and upfront brain RT (HR = 0.47, p = 0.001). mOS was independently correlated with being female (HR = 0.54, p = 0.007), ECOG 3–4 (HR = 10.47, p < 0.001), BM number>3 (HR = 2.19, p = 0.002), and third‐generation TKI (HR = 0.54, p = 0.044) or antiangiogenic drugs (HR = 0.11, p = 0.005) as first/second‐line therapy.ConclusionsUpfront brain RT based on first‐line EGFR‐TKI might improve IC‐PFS but not OS in EGFR‐mutant lung adenocarcinoma patients, indicating potential survival benefit from brain SRS and early application of drugs with higher intracranial activity.

Comparative assessment of NOIR-SS and ddPCR for ctDNA detection of EGFR L858R mutations in advanced L858R-positive lung adenocarcinomas

Genotyping epidermal growth factor receptor (EGFR) is an essential process to indicate lung adenocarcinoma patients for the most appropriate treatment. Liquid biopsy using circulating tumor DNA (ctDNA) potentially complements the use of tumor tissue biopsy for identifying genotype-specific mutations in cancer cells. We assessed the performance of a high-fidelity sequencing method that uses molecular barcodes called the nonoverlapping integrated read sequencing system (NOIR-SS) for detecting EGFR L858R-mutated alleles in 33 advanced or recurrent patients with L858R mutation-positive lung adenocarcinoma revealed by matched tissue biopsy. We compared NOIR-SS with site-specific droplet digital PCR (ddPCR), which was taken as the reference, in terms of sensitivity and ability to quantify L858R variant allele fractions (VAFs). NOIR-SS and ddPCR had sensitivities of 87.9% (29/33) and 78.8% (26/33) for detecting L858R alleles, respectively. The VAFs measured by each assay were strongly correlated. Notably, one specimen was positive with a VAF of 30.12% for NOIR-SS but marginally positive with that of 0.05% for ddPCR because of a previously poorly recognized mechanism: two-base substitution-induced L858R (c.2573_2574delinsGA). These results indicate that NOIR-SS is a useful method for detecting ctDNA, potentially overcoming a limitation of ddPCR which highly depends on the binding ability of primers to specific targeting sequences.

TP53 mutations in circulating tumor DNA in advanced epidermal growth factor receptor-mutant lung adenocarcinoma patients treated with gefitinib

Tumor protein p53 (TP53) is a tumor suppressor gene and TP53 mutations are associated with poor prognosis in non-small cell lung cancer. However, the in-depth classification of TP53 and its relationship with treatment response and prognosis in epidermal growth factor receptor (EGFR)-mutant tumors treated with EGFR tyrosine kinase inhibitors are unclear. Circulating tumor DNA was prospectively collected at baseline in advanced treatment-naïve EGFR-mutant lung adenocarcinoma patients treated with gefitinib in an open-label, single-arm, prospective, multicenter, phase 2 clinical trial (BENEFIT trial) and analyzed using next-generation sequencing. Survival was estimated using the Kaplan–Meier method. Of the 180 enrolled patients, 115 (63.9%) harbored TP53 mutations. The median progression-free survival (PFS) and overall survival (OS) of patients with TP53-wild type tumors were significantly longer than those of patients with TP53-mutant tumors. Mutations in exons 5–8 accounted for 80.9% of TP53 mutations. Mutations in TP53 exons 6 and 7 were significantly associated with inferior PFS and OS compared to wild-type TP53. TP53 mutation also influenced the prognosis of patients with different EGFR mutations. Patients with TP53 and EGFR exon 19 mutations had significantly longer PFS and OS than patients with TP53 and EGFR L858R mutations, and both groups had worse survival than patients with only EGFR mutations. Patients with TP53 mutations, especially in exons 6 and 7, had a lower response rate and shorter PFS and OS when treated with gefitinib. Moreover, TP53 exon 5 mutation divided TP53 mutations in disruptive and non-disruptive types.