Non-small Cell Lung Cancer with EGFR or HER2 Exon 20 Insertion Mutations: Diagnosis and Treatment Options

Efficacy and safety outcomes of emerging EGFR‑TKIs for patients with non‑small cell lung cancer with EGFR exon 20 insertion mutations: A systematic review and meta‑analysis

Lung cancer remains a leading cause of mortality worldwide, with non-small cell lung cancer (NSCLC) accounting for ~85% of all lung cancer cases. Epidermal growth factor receptor (EGFR) exon 20 insertion mutant NSCLC is rare and associated with poor outcomes. Several novel generations (third-generation) of EGFR-tyrosine kinase inhibitors (TKIs) have been developed for the treatment of NSCLC and have shown antitumour potential. Therefore, the present study reviewed their efficacy and safety outcomes for this condition. A thorough literature searching was performed using the Cochrane Library, Web of Science, PubMed and Embase databases. Clinical trials published in English and reporting overall response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS) and treatment relevant adverse events (TRAEs) of grade ≥3 were included for further analysis. A total of 13 studies were included. All included studies reported ORRs with a pooled ORR of 0.486 [95% confidence interval (CI), 0.369-0.602]. Subgroup analysis revealed the following ORRs: 0.731 (95% CI, 0.560-0.901; I2=0%) for YK-029A; 0.608 (95% CI, 0.511-0.705; I2=0%) for sunvozertinib; 0.602 (95% CI, 0.440-0.764; I2=80.2%) for furmonertinib; 0.602 (95% CI, 0.486-0.718; I2=84.5%) for befotertinib; 0.566 (95% CI, 0.236-0.896; I2=96.3%) for amivantamab; 0.444 (95% CI, 0.215-0.674; I2=0%) for BEBT-109; and 0.256 (95% CI, 0.178-0.334; I2=75.0%) for poziotinib. The pooled DCR, median PFS and median OS were 0.843 (95% CI, 0.740-0.946), 10.11 months (95% CI, 9.58-10.64 months; I2=78.8%; P<0.001) and 23.00 months (95% CI, 20.30-25.69 months; I2=44.8; P=0.178), respectively. The pooled incidence of TRAEs of grade ≥3 was 0.458 (95% CI, 0.336-0.580; I2=96.9%; P<0.001), with the incidence of the three most reported TRAEs (diarrhoea, thrombocytopenia and anaemia) demonstrated to be 0.112 (95% CI, 0.060-0.164), 0.065 (95% CI, -0.012-0.141) and 0.040 (95% CI, 0.005-0.076), respectively. In conclusion, the emerging EGFR-TKIs for NSCLC with EGFR exon 20 insertion have a promising treatment outcome with a manageable safety profile. However, further analysis is needed when more clinical data are released.

Differences between lung adenocarcinoma and lung squamous cell carcinoma: Driver genes, therapeutic targets, and clinical efficacy

With the rapid advancements in second-generation gene sequencing technologies, a growing number of driver genes and associated therapeutic targets have been unveiled for lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC). While they are clinically classified as non-small cell lung cancer (NSCLC), they display distinct genomic features and substantial variations in clinical efficacy, underscoring the need for particular attention. Hence, this review provides a comprehensive overview of the latest advancements in driver genes, epigenetic targets, chemotherapy, targeted therapy, and immunotherapy for LUAD and LUSC. Additionally, it delves into the distinctions in signaling pathways and pivotal facets of clinical management specific to these two categories of lung cancer. Moreover, we furnish pertinent details regarding clinical trials pertaining to driver genes and epigenetics, thus establishing a theoretical foundation for the realization of precision treatments for LUAD and LUSC.

Genomic and clinical characterization of HER2 exon 20 mutations in non-small cell lung cancer: insights from a multicenter study in South China

BACKGROUND

The objective of this study was to investigate the clinical and genetic characteristics and clinical relevance of HER2 exon 20 oncogenic variants in non-small cell lung cancer (NSCLC) patients.

METHODS

This prospective study analyzed 51 NSCLC patients with HER2 mutations, identified via next-generation sequencing (NGS) of tissue, blood, cerebrospinal fluid, or pleural effusion samples. Patients were grouped based on the presence of exon 20 mutations (exon 20 vs. non-exon 20) and further divided based on whether they had received prior anti-tumor treatments (baseline vs. non-baseline). Clinical and genetic data, treatment responses were analyzed. Progression-free survival (PFS) and overall survival (OS) were evaluated using Kaplan-Meier methods and compared with log-rank tests. Gene ontology (GO) analysis was performed to uncover the biological significance of the mutated genes.

RESULTS

In a cohort of 651 NSCLC patients, 51 (7.83%) harbored HER2 alterations, including 20 (3.08%) with exon 20 mutations. The median age of the HER2-altered subgroup was 58.5 years. Adenocarcinoma was the most prevalent subtype (96.1%), and most patients presented at stage IV (72.5%). The most common metastatic sites were the lungs (68.6%), lymph nodes (52.9%), and brain (43.1%). Among the HER2 mutated patients, 20 (39.3%) had exon 20 mutations. Exon 20 mutations were more prevalent in the non-baseline group (55.0% vs. 29.0%, P = 0.049) and males (75.0%, P = 0.025). These mutations were associated with a higher rate of metastasis to the lungs, lymph nodes (P < 0.001). Patients with exon 20 mutations demonstrated poorer overall survival (OS) outcomes (P = 0.048). No significant differences were observed in age, smoking history, histological subtype, or TNM stage at diagnosis between groups. The majority of exon 20 mutations were in-frame indel mutations (92.0%), with the most common specific mutation being p.Y772_A775dup (70%). Gene Ontology (GO) analysis linked exon 20 mutations to unregulated protein kinase activity and anoikis.

CONCLUSIONS

Our study found that NSCLC patients with HER2 exon 20 oncogenic variants have a higher risk of metastasis and drug resistance, leading to worse outcomes than non-exon 20 mutations. This highlights the urgent need for targeted therapies aimed at exon 20 insertions to improve survival and treatment outcomes in this subgroup.

Ensartinib for EML4-ALK-positive lung adenocarcinoma with comorbid mutations in TP53, EGFR, and ERBB2: a case report

Background

In non-small cell lung cancer (NSCLC), anaplastic lymphoma kinase (ALK) gene rearrangements are commonly detected in lung adenocarcinoma. ALK-positive (ALK+) patients may occasionally exhibit concurrent genetic alterations that potentially impact prognosis. New therapeutic strategies are needed for ALK+ NSCLC patients with multiple simultaneous gene mutations.

Case presentation

A 58-year-old man was diagnosed with lung adenocarcinoma (stage IVB, T4N3M1c) with an echinoderm microtubule-associated protein-like 4-ALK+ (EML4-ALK+) rearrangement, harboring tumor protein 53 (TP53), epidermal growth factor receptor (EGFR), and receptor tyrosine-protein kinase erbB-2 (ERBB2) mutations. After three cycles of chemotherapy, the patient developed intolerance. Subsequently, ensartinib (225 mg daily) was administered orally on April 14, 2021. After 3 months of ensartinib treatment, the patient achieved a partial response and reached stable disease at six months, which sustained for 30 months till April 8, 2024, with grade 1 rash and no brain metastases. Currently, the patient remains on ensartinib treatment, without disease progression.

Conclusion

This case demonstrates the potential for ensartinib in the treatment of EML4-ALK+ lung adenocarcinoma with multiple gene mutations. Further investigation through clinical trials is needed to evaluate the safety and efficacy of this targeted therapy.

Evaluation of the safety profile of amivantamab based on real-world evidence: a call to vigilance

BACKGROUND

Amivantamab has been approved for EGFR exon 20 insertion-mutated non-small-cell lung cancer. The aim of this study was to perform an in-depth analysis of its safety profile.

RESEARCH DESIGN AND METHODS

Safety reports were collected from the database of the Food and Drug Administration Adverse Event Reporting System from April 2021 to September 2023, and the reporting odds ratio (ROR) method was used to detect potential safety signals. Mobocertinib, an agent with similar properties to amivantamab, served as a control for comparison.

RESULTS

A total of 88 safety signals were detected, most of which were novel. In comparison with mobocertinib, amivantamab appeared to cause more injury, poisoning, and procedural complications (ROR = 15.54, 95% CI 10.25-23.58); respiratory, thoracic, and mediastinal disorders (ROR = 1.92, 95% CI 1.57-2.34); infections and infestations (ROR = 1.39, 95% CI 1.09-1.76); blood and lymphatic system disorders (ROR = 9.57, 95% CI 6.17-14.84); and immune system disorders (ROR = 6.41, 95% CI 3.14-13.12). Moreover, amivantamab was associated with higher risks of thrombosis events, bone marrow suppression, skin and soft tissue infection, deterioration of respiratory symptoms, and noninfectious pneumonitis.

CONCLUSION

The safety profile of amivantamab requires attention; particularly, monitoring of the adverse drug events described above is necessary during its administration.

NRP1 overexpression potentially enhances osimertinib resistance in NSCLC via activation of the PI3K/AKT signaling pathway

Resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) is the main cause of mortality in lung cancer. This study aimed to investigate the roles of neuropilin 1 (NRP1) in non-small cell lung cancer (NSCLC). NRP1 expression was assessed in tumor tissues from patients with osimertinib-resistant (OR) NSCLC and osimertinib-responsive NSCLC as well as in patients with paracancerous NSCLC tissues who did not undergo radiotherapy or chemotherapy. In vitro experiments were conducted using five cell lines: BEAS-2B, HCC827, and PC9 cells, and the constructed OR cell lines, HCC827-OR and PC9-OR. HCC827-OR cells showing significant differences in osimertinib IC50 were selected for further study. After investigating the effects of altering NRP1 expression on cell sensitivity to osimertinib, NRP1 expression was inhibited to further investigate changes in cell viability, proliferation, migration, invasion, and apoptosis in OR cells. Additionally, bioinformatics techniques were used to detect targets (Integrin β3) and signaling pathways (PI3K/AKT) downstream of NRP1; subsequent cell experiments verified their interactivity. Finally, an orthotopic mouse tumor model was constructed using HCC827-OR cells treated with a PI3K/AKT signaling pathway activator (740Y-P), allowing exploration of the role played by the PI3K/AKT signaling pathway via NRP1 regulation on NSCLC resistance both in vivo and in vitro. Results showed that NRP1 expression was significantly increased in the cells of patients with NSCLC-OR, and increased NRP1 expression reduced HCC827 cell sensitivity to osimertinib. Both in vitro and in vivo experiments showed that NRP1 deficiency mediated by NRP1 inhibitors inhibited HCC827-OR cell proliferation, migration, and invasion, promoted tumor cell apoptosis, and enhanced osimertinib efficacy. In contrast, 740Y-P partially inhibited the effects of NRP1 inhibitors combined with osimertinib on the PI3K/AKT signaling pathway and on tumor growth in vivo and in vitro. Cellular experimental results showed that NRP1 positively regulates the Integrin β3 expression and activation of the PI3K/AKT signaling pathway. Bioinformatics analysis showed that both NRP1 and Integrin β3 may jointly participate in regulating the PI3K/AKT signaling pathway. In conclusion, our findings suggest that elevated NRP1 expression in NSCLC tumor tissues may promote NSCLC resistance to osimertinib by activating the PI3K/AKT signaling pathway, and integrin β3 potentially being involved in this process. These insights may provide a novel strategy for combination therapy for OR NSCLC.

In-depth exploration of the focus issues of TKI combined with radiotherapy for EGFR-mutant lung adenocarcinoma patients with brain metastasis: a systematic analysis based on literature metrology, meta-analysis, and real-world observational data

BACKGROUND

There is a growing interest in utilizing a combination of brain radiotherapy (RT) and tyrosine kinase inhibitors (TKIs) for patients diagnosed with brain metastases (BM) in epidermal growth factor receptor (EGFR) mutation-positive lung adenocarcinoma (LAC). The current status of this treatment strategy remains a subject of debate.

METHODS

We initiated our study by conducting a comprehensive literature search using the SCI-expanded database of Web of Science Core Collection (WoSCC). We utilized the VOSPviewer software to analyze various aspects of the research, including the year of publication, authorship, keywords, and country.Subsequently, we performed an extensive and systematic literature search on popular online databases. Our primary outcome measures were overall survival (OS) and intracranial progression-free survival (iPFS), both quantified by hazard ratios (HRs). Additionally, for data verification, we included data from patients in non-small cell lung cancer with brain metastasis who underwent therapeutic intervention at the Cancer Prevention and Treatment Center of Sun Yat-sen University and the Radiotherapy Department of Hanzhong Central Hospital between August 2012 and November 2021.

RESULTS

The bibliometric analysis revealed an increasing trend in research focused on the combination of RT and TKIs for the management of lung cancer brain metastases over the previous decade. Then, nine studies consistent with the research direction were included for meta-analysis. The meta-analysis showed that the OS (HR = 0.81, 95% confidence interval: 0.69-0.94; P = 0.007) and iPFS (HR = 0.71, 95% confidence interval: 0.61-0.82; P < 0.001) of the combination therapy were significantly prolonged. Finally, 168 EGFR-mutated BM advanced LAC patients in the real world were verified, and the median iPFS of the combination therapy (n = 88 and EGFR-TKIs alone (n = 80) were 16.0 and 9.0 months, respectively, (P < 0.001). The median OS was 29.0 and 27.0 months, respectively, with no dramatic difference (P = 0.188).

CONCLUSIONS

Research on EGFR-mutant LAC brain metastasis has turned towards exploring optimal treatment strategies for this condition. Our meta-analysis and real-world data analysis consistently demonstrate that combination therapy offers a substantial improvement in patient survival compared to EGFR-TKI monotherapy. Notably, among patients undergoing salvage radiotherapy (RT), our subgroup analysis reveals that those initially treated with third-generation TKIs experience more significant benefits than those treated with first- or second-generation TKIs.

Unlocking the future of cancer diagnosis - promises and challenges of ctDNA-based liquid biopsies in non-small cell lung cancer

The advent of liquid biopsies has brought significant changes to the diagnosis and monitoring of non-small cell lung cancer (NSCLC), presenting both promise and challenges. Molecularly targeted drugs, capable of enhancing survival rates, are now available to around a quarter of NSCLC patients. However, to ensure their effectiveness, precision diagnosis is essential. Circulating tumor DNA (ctDNA) analysis as the most advanced liquid biopsy modality to date offers a non-invasive method for tracking genomic changes in NSCLC. The potential of ctDNA is particularly rooted in its ability to furnish comprehensive (epi-)genetic insights into the tumor, thereby aiding personalized treatment strategies. One of the key advantages of ctDNA-based liquid biopsies in NSCLC is their ability to capture tumor heterogeneity. This capability ensures a more precise depiction of the tumor's (epi-)genomic landscape compared to conventional tissue biopsies. Consequently, it facilitates the identification of (epi-)genetic alterations, enabling informed treatment decisions, disease progression monitoring, and early detection of resistance-causing mutations for timely therapeutic interventions. Here we review the current state-of-the-art in ctDNA-based liquid biopsy technologies for NSCLC, exploring their potential to revolutionize clinical practice. Key advancements in ctDNA detection methods, including PCR-based assays, next-generation sequencing (NGS), and digital PCR (dPCR), are discussed, along with their respective strengths and limitations. Additionally, the clinical utility of ctDNA analysis in guiding treatment decisions, monitoring treatment response, detecting minimal residual disease, and identifying emerging resistance mechanisms is examined. Liquid biopsy analysis bears the potential of transforming NSCLC management by enabling non-invasive monitoring of Minimal Residual Disease and providing early indicators for response to targeted treatments including immunotherapy. Furthermore, considerations regarding sample collection, processing, and data interpretation are highlighted as crucial factors influencing the reliability and reproducibility of ctDNA-based assays. Addressing these challenges will be essential for the widespread adoption of ctDNA-based liquid biopsies in routine clinical practice, ultimately paving the way toward personalized medicine and improved outcomes for patients with NSCLC.

Efficacy and Safety of Amivantamab in Advanced or Metastatic EGFR-Mutant Non-Small Cell Lung Cancer: A Systematic Review

Objectives: This systematic review aimed to examine the efficacy and safety profile of amivantamab in patients with advanced or metastatic non-small cell lung cancer (NSCLC) and EGFR mutations. Methods: Three scientific databases, PubMed, Cochrane library and ClinicalTrials.gov were searched for relevant articles up until 30 June 2024. Progression-free survival (PFS), overall survival (OS), objective response rate (ORR) and ≥3 grade adverse events (AE) were the outcomes of interest. Results: Five clinical trials were included in this systematic review, reporting data from 1124 patients (safety population; n = 1091 efficacy population), who received amivantamab as a monotherapy or in combination with other treatments, both in a first-line and in a relapsed/refractory setting. The median PFS for groups of patients that received amivantamab ranged from 4.3 to 8.3 months, while the lowest observed OS was 10.2 months. The ORR ranged from 30% to 73%. The rate of grade 3 or higher AEs ranged from 35% to 92%, while serious AEs ranged from 29% to 52%. Infusion-related reactions (IRRs) ranged from 42% to 78% among patients that received amivantamab intravenously, while a 13% IRR rate was found in a group of patients that received amivantamab subcutaneously. Conclusions: Current evidence suggests that amivantamab is an effective treatment option for patients with advanced or metastatic NSCLC with EGFR mutations. Amivantamab-based combinations may prolong survival both in the treatment of naïve patients and those who have progressed on chemotherapy or tyrosine kinase inhibitors.

Prevalence and treatment of human epidermal growth factor receptor 2-altered non-small cell lung cancer: a retrospective analysis and systematic literature review

Human epidermal growth factor receptor 2 (HER2) is known for its oncogenic activities in diverse cancers, including non-small cell lung cancer (NSCLC). However, the prevalence of HER2 alterations in Malaysian NSCLC patients remains unreported. This study examined the prevalence and characteristics of HER2 mutations and amplification in a Malaysian cohort. Additionally, a systematic review was conducted to evaluate the global prevalence of HER2 alterations in NSCLC, as well as the efficacy of HER2-targeted therapies observed in clinical trials. NSCLC tumour samples received from October 2019 to December 2022 for next-generation sequencing diagnostics were included in the retrospective analysis. In this patient cohort, HER2 alteration was present in 5.8% of patients; 3.9% had HER2 mutations, 1.5% had HER2 amplifications and 0.4% were both HER2-mutated and amplified. HER2 exon 20 insertions were the most common HER2 variants, detected in 47/59 (79.7%) of HER2-mutated patients. Among cases with HER2 exon 20 insertions, the Y772_A775dup variant was found in 34 patient samples. HER2-mutated patients were significantly younger than non-HER2-mutants (61 versus 64 years old; p = 0.046) and were inclined to be female and never-smokers, albeit not statistically significant. Patients with HER2 amplification were more likely to have progressed post-tyrosine kinase inhibitor therapy (p = 0.015). The systematic review highlighted a global variation in the prevalence of HER2 alterations in NSCLC, ranging from 0.3% to 9.1% for mutations and 0.2% to 19% for amplification. Finally, phase II clinical trials involving HER2-altered NSCLC patients demonstrated promising treatment outcomes with trastuzumab deruxtecan, trastuzumab emtansine, pyrotinib, pyrotinib + apatinib and trastuzumab + pertuzumab + docetaxel. In conclusion, the prevalence of HER2 alteration among Malaysian NSCLC patients falls within the global range. A systematic review of clinical trials revealed promising treatment outcomes and Malaysian NSCLC patients with HER2 alterations are anticipated to similarly benefit from HER2-targeted therapies.

Proximal Femoral Metastasis From Epidermal Growth Factor Receptor-Mutated Lung Adenocarcinoma Mimicking Osteosarcoma on Magnetic Resonance Imaging

The aggressive nature of lung cancer is frequently accompanied by a high incidence of bone metastasis; however, proximal femoral metastasis from lung cancer is comparatively uncommon when compared to other malignancies. In this report, we present the case of a 53-year-old Asian male who presented with pain in the left thigh and back. Magnetic resonance imaging revealed severe bone destruction with involvement of adjacent soft tissue mass at the left thigh, exhibiting imaging findings that mimic osteosarcoma. Subsequent bone biopsy confirmed the diagnosis of epidermal growth factor receptor (EGFR)-mutated lung adenocarcinoma with bone metastasis. The patient achieved survival following administration of osimertinib and underwent surgery for femoral metastases without palliative surgery for lung cancer. Therefore, proximal femoral metastasis from EGFR-mutated lung adenocarcinoma should be considered as a differential diagnosis in patients suspected to have osteosarcoma. The imaging findings of proximal femoral metastasis from EGFR-mutated lung adenocarcinoma were presented, and their therapeutic management was discussed.

[Chinese Expert Consensus on the Standardized Diagnosis and Treatment of Non‑small Cell Lung Cancer with EGFR Exon 20 Insertion Mutations (2024 Edition)]

The standard clinical practice of managing the non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) exon 20 insertion (ex20ins) mutations was elaborated in Chinese expert consensus on non‑small cell lung cancer with EGFR exon 20 insertion mutations (2023 edition), and this rare subset has gradually attracted attention recently. With the deepening of treatment area exploration and the approval of new targeted drugs, there are more options for the diagnosis and treatment of EGFR ex20ins positive NSCLC patients. Therefore, based on the previous version of consensus, the expert panel has updated this consensus on the standardized clinical diagnosis and treatment of EGFR ex20ins mutation NSCLC through reference to literature and clinical data, and combined with the experts' own clinical experience. The updated recommendations includes disease congnition, testing methods, therapy and recent relevant clinical trials for NSCLC patients with EGFR ex20ins mutation, in order to provide better medication reference for clinical physicians.
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Discovery of Novel 5,6-Dihydro-4H-pyrido[2,3,4-de]quinazoline Irreversible Inhibitors Targeting Both Wild-Type and A775_G776insYVMA Mutated HER2 Kinases

HER2 mutations were seen in 4% of non-small-cell lung cancer (NSCLC) patients. Most of these mutations (90%) occur as an insertion mutation within the exon 20 frame, leading to the downstream activation of the PI3K-AKT and RAS/MAPK pathways. However, no targeted therapies have yet been approved worldwide. Here a novel series of highly potent HER2 inhibitors with a pyrido[2,3,4-de]quinazoline core were designed and developed. The derivatives with the pyrido[2,3,4-de]quinazoline core displayed superior efficacy of antiproliferation in BaF3 cells harboring HER2insYVMA mutation compared with afatinib and neratinib. Rat studies showed that 8a and 9a with the newly developed core have good pharmacokinetic properties with an oral bioavailability of 41.7 and 42.0%, respectively. Oral administration of 4a and 10e (30 mg/kg, QD) displayed significant antitumor efficacy in an in vivo xenograft model. We proposed promising strategies for the development of HER2insYVMA mutant inhibitors in this study.

A study of high dose furmonertinib in EGFR exon 20 insertion mutation-positive advanced non-small cell lung cancer

Background

The epidermal growth factor receptor (EGFR) ex20ins mutation, as a rare subtype of mutation, has gradually attracted attention. Its heterogeneity is high, its prognosis is extremely poor, and the efficacy of existing traditional treatment plans is limited. In this study, we aimed to evaluate efficacy of high dose furmonertinib as a first-line treatment for EGFR ex20ins-positive NSCLC.

Methods

This is a retrospective, multi-center, non-interventional study. From May 2021 to March 2023, 9 NSCLC patients with EGFR ex20ins were enrolled. Efficacy and safety of 160 mg furmonertinib were evaluated. Objective response rate (ORR), disease control rate (DCR), median progression-free survival (PFS) and treatment related adverse events (TRAEs) were assessed.

Results

Of the evaluated patients, six patients experienced partial remission (PR), two patients experienced stable disease (SD) and one patient experienced progress disease (PD). Data indicated 66.7% ORR and 88.9% DCR. The median progression free survival (PFS) was 7.2 months (95% CI: 6.616 - 7.784). Besides, a longgest PFS with 18 months was found in one patient with p.H773_V774insGTNPH mutation. No ≥ level 3 adverse events have been found.

Conclusions

The study proved the potential efficacy of 160mg furmonertinib in patients with advanced NSCLC with EGFR ex20ins. Meanwhile, 160mg furmonertinib had a good safety profile.

[Chinese Expert Consensus on Non-small Cell Lung Cancer with EGFR Exon 20 Insertion Mutations (2023 Edition)]

With the development of precision diagnosis and treatment for non-small cell lung cancer (NSCLC), the epidermal growth factor receptor (EGFR) exon 20 insertion (ex20ins) mutations, as a rare subset of EGFR mutaions, have gradually attracted attention recently. The heterogeneity of EGFR ex20ins mutations is very high, different variants have different clinical benefits, and the prognosis is extremely poor. The available traditional treatment outcomes are poor in patients with EGFR ex20ins positive NSCLC and polymerase chain reaction (PCR) tests would miss aprocimately 50% of the variants. Therefore, high attention should be paid to EGFR ex20ins positive NSCLC during the clinical practice. The expert panel has formed a consensus on the standardized clinical diagnosis and treatment of EGFR ex20ins mutation NSCLC through reference to literature and clinical data, and combined with the experts' own clinical experience, the consensus recommendations including clinicopathologic characteristics, therapies, testing methods and recent relevant clinical trials for NSCLC patients with EGFR ex20ins mutation, in order to provide medication reference for clinical physicians at all levels.

Antibody-drug conjugates and bispecific antibodies targeting cancers: applications of click chemistry

Engineering approaches using antibody drug conjugates (ADCs) and bispecific antibodies (bsAbs) are designed to overcome the limitations of conventional chemotherapies and therapeutic antibodies such as drug resistance and non-specific toxicity. Cancer immunotherapies have been shown to be clinically successful with checkpoint blockade and chimeric antigen receptor T cell therapy; however, overactive immune systems still represent a major problem. Given the complexity of a tumor environment, it would be advantageous to have a strategy targeting two or more molecules. We highlight the necessity and importance of a multi-target platform strategy against cancer. Approximately 400 ADCs and over 200 bsAbs are currently being clinically developed for several indications, with promising signs of therapeutic activity. ADCs include antibodies that recognize tumor antigens, linkers that stably connect drugs, and powerful cytotoxic drugs, also known as payloads. ADCs have direct therapeutic effects by targeting cancers with a strong payload. Another type of drug that uses antibodies are bsAbs, targeting two antigens by linking to antigen recognition sites or bridging cytotoxic immune cells to tumor cells, resulting in cancer immunotherapy. Three bsAbs and one ADC have been approved for use by the FDA and the EMA in 2022. Among these, two of the bsAbs and the one ADC are used for cancers. We introduced that bsADC, a combination of ADC and bsAbs, has yet to be approved and several candidates are in the early stages of clinical development in this review. bsADCs technology helps increase the specificity of ADCs or the internalization and killing ability of bsAbs. We also briefly discuss the application of click chemistry in the efficient development of ADCs and bsAbs as a conjugation strategy. The present review summarizes the ADCs, bsAbs, and bsADCs that have been approved for anti-cancer or currently in development. These strategies selectively deliver drugs to malignant tumor cells and can be used as therapeutic approaches for various types of cancer.