Targeting EGFR exon 20 insertion mutations in non-small cell lung cancer

ESMO expert consensus statements on the management of EGFR mutant non-small-cell lung cancer

The European Society for Medical Oncology (ESMO) held a virtual consensus-building process on epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancer in 2021. The consensus included a multidisciplinary panel of 34 leading experts in the management of lung cancer. The aim of the consensus was to develop recommendations on topics that are not covered in detail in the current ESMO Clinical Practice Guideline and where the available evidence is either limited or conflicting. The main topics identified for discussion were: (i) tissue and biomarkers analyses; (ii) early and locally advanced disease; (iii) metastatic disease and (iv) clinical trial design, patient's perspective and miscellaneous. The expert panel was divided into four working groups to address questions relating to one of the four topics outlined above. Relevant scientific literature was reviewed in advance. Recommendations were developed by the working groups and then presented to the entire panel for further discussion and amendment before voting. This manuscript presents the recommendations developed, including findings from the expert panel discussions, consensus recommendations and a summary of evidence supporting each recommendation.

EGFR-Mutant Non-Small-Cell Lung Cancer at Surgical Stages: What Is the Place for Tyrosine Kinase Inhibitors?

Simple Summary

Tyrosine kinase inhibitors are drugs targeting the epidermal growth factor receptor. In lung cancer, they are used to treat advanced EGFR-mutant diseases, and more recently, one has been approved for adjuvant therapy. Even though publications on the topic are numerous, conclusions are difficult to interpret and are sometimes contradictory. We therefore reviewed the literature in order to present an overview of up-to-date data regarding the adjuvant and neoadjuvant use of tyrosine kinase inhibitors, with particular attention given to their benefits, proven or expected, as well as what challenges could be faced when entering them as protocols in standard care.

Abstract

The ADAURA trial has been significant for the perception of EGFR tyrosine kinase inhibitors (TKIs) as a tool for early stage non-small-cell lung cancer (NSCLC). It produced such great insight that the main TKI, Osimertinib, was rapidly integrated into international guidelines for adjuvant use. However, EGFR-mutant NSCLC is a complex entity and has various targeting drugs, and the benefits for patients might not be as clear as they seem. We reviewed trials and meta-analyses considering TKI adjuvant and neoadjuvant use. We also explored the influence of mutation variability and financial evaluations. We found that TKIs often show disease-free survival (DFS) benefits, yet studies have struggled to improve the overall survival (OS); however, the results from the literature might be confusing because of variability in the stages and mutations. The safety profiles and adverse events are acceptable, but costs remain high and accessibility might not be optimal. TKIs are promising drugs that could allow for tailored treatment designs.

A Novel HER2-Selective Kinase Inhibitor Is Effective in HER2 Mutant and Amplified Non-Small Cell Lung Cancer

In-frame insertions in exon 20 of HER2 are the most common HER2 mutations in patients with non-small cell lung cancer (NSCLC), a disease in which approved EGFR/HER2 tyrosine kinase inhibitors (TKI) display poor efficiency and undesirable side effects due to their strong inhibition of wild-type (WT) EGFR. Here, we report a HER2-selective covalent TKI, JBJ-08-178-01, that targets multiple HER2 activating mutations, including exon 20 insertions as well as amplification. JBJ-08-178-01 displayed strong selectivity toward HER2 mutants over WT EGFR compared with other EGFR/HER2 TKIs. Determination of the crystal structure of HER2 in complex with JBJ-08-178-01 suggests that an interaction between the inhibitor and Ser783 may be responsible for HER2 selectivity. The compound showed strong antitumoral activity in HER2-mutant or amplified cancers in vitro and in vivo. Treatment with JBJ-08-178-01 also led to a reduction in total HER2 by promoting proteasomal degradation of the receptor. Taken together, the dual activity of JBJ-08-178-01 as a selective inhibitor and destabilizer of HER2 represents a combination that may lead to better efficacy and tolerance in patients with NSCLC harboring HER2 genetic alterations or amplification.

SIGNIFICANCE

This study describes unique mechanisms of action of a new mutant-selective HER2 kinase inhibitor that reduces both kinase activity and protein levels of HER2 in lung cancer.

EGFR exon 20 insertion mutations in advanced non-small-cell lung cancer: current status and perspectives

Platinum-based chemotherapy was previously the first-choice treatment for lung cancer. The discovery of epidermal growth factor receptor (EGFR) gene mutations and the development of EGFR tyrosine kinase inhibitors (TKIs) marked the beginning of the targeted therapy era for non-small-cell lung cancer (NSCLC). Thirty percent of NSCLC patients carry EGFR gene mutations. For these advanced NSCLC patients, EGFR-TKIs are currently preferred for their superior activity and survival benefits over platinum-based chemotherapy. However, therapeutic efficacy is quite different in patients with EGFR exon 20 insertion (ex20ins) mutations versus common mutations. Patients with ex20ins mutations are insensitive to EGFR-TKIs and have poor prognosis. Some drugs targeting EGFR ex20ins mutations have been approved. Here, we systematically reviewed the recent clinical research of and treatments used for EGFR ex20ins mutations, summarized the latest data on emerging therapies, and discussed future prospects and treatments.

Epidermal growth factor receptor-targeted therapy for the treatment of non-small cell lung cancer: A review of phase II and III trials

INTRODUCTION

EGFR is one of the most common driver gene mutations in lung cancer. EGFR-TKI monotherapy and EGFR-TKI combined with chemotherapy or anti-angiogenesis drugs have significantly prolonged the survival of patients with EGFR-mutant NSCLC. However, disease progression caused by acquired resistance to EGFR-TKIs is inevitable. And patients with EGFR exon 20ins showed limited efficacy to EGFR-TKIs.

AREAS COVERED

In this review, we initially evaluated the efficacy of existing treatments for EGFR-mutant NSCLC. Second, we reviewed the ongoing phase II and III clinical trials, provide the latest results, discuss the scientific rationale of these trials and the potential development issues.

EXPERT OPINION

The application of EGFR-TKIs has greatly changed the therapeutic strategies for advanced and resected NSCLC with EGFR mutations, and the 5-year OS rate for advanced NSCLC was close to 40%. The current research direction for the treatment of patients with EGFR mutations focuses on the following three aspects: uncommon EGFR mutation subtypes NSCLC, brain metastases, and EGFR TKI-based combination therapy. Future studies on EGFR-mutant NSCLC therapy will focus on overcoming EGFR-TKI-related resistance, preventing drug resistance in advance, and developing bispecific antibody drugs. ADCs may be the promising strategy for patients with acquired resistance to EGFR-TKIs.

EGFR Mutations in Head and Neck Squamous Cell Carcinoma

EGFR is a prototypical receptor tyrosine kinase that is overexpressed in multiple cancers including head and neck squamous cell carcinoma (HNSCC). The standard of care for HNSCC remains largely unchanged despite decades of research. While EGFR blockade is an attractive target in HNSCC patients and anti-EGFR strategies including monoclonal antibodies and kinase inhibitors have shown some clinical benefit, efficacy is often due to the eventual development of resistance. In this review, we discuss how the acquisition of mutations in various domains of the EGFR gene not only alter drug binding dynamics giving rise to resistance, but also how mutations can impact radiation response and overall survival in HNSCC patients. A better understanding of the EGFR mutational landscape and its dynamic effects on treatment resistance hold the potential to better stratify patients for targeted therapies in order to maximize therapeutic benefits.

Non-Small-Cell Lung Cancer in 2022: A Review for General Practitioners in Oncology

Lung cancer is the leading cause of cancer death in Canada and a significant cause of morbidity for patients and their loved ones. There have been rapid advances in preventing, screening and treating this disease. Here, we present a contemporary review of treatment of non-small cell lung cancer in Canada based on current best practices. The focus of this review is to highlight recent data in screening for lung cancer, management of patients with early and locally-advanced non-small cell lung cancer, as well as management of patients with metastatic disease. There is a special focus on the incorporation of immunotherapy into practice and its associated toxicities.

Treatment outcome of atypical EGFR mutations in the German National Network Genomic Medicine Lung Cancer (nNGM)

BACKGROUND

Atypical EGFR mutations occur in 10-30% of NSCLC patients with EGFR mutations and their sensitivity to classical EGFR-tyrosine kinase inhibitors (TKI) is highly heterogeneous. Patients harboring one group of uncommon, recurrent EGFR mutations (G719X, S768I, L861Q) respond to EGFR-TKI. Exon 20 insertions are mostly insensitive to EGFR-TKI but display sensitivity to exon 20 inhibitors. Clinical outcome data of patients with very rare point and compound mutations upon systemic treatments are still sparse to date.

PATIENTS AND METHODS

In this retrospective, multi-center study of the national Network Genomic Medicine (nNGM) in Germany, 856 NSCLC cases with atypical EGFR mutations including co-occuring mutations were reported from 12 centers. Clinical follow-up data after treatment with different EGFR-TKI, chemotherapy and immune checkpoint inhibitors were available from 260 patients. Response to treatment was analyzed in three major groups: (1) uncommon mutations (G719X, S7681, L861Q and combinations), (2) exon 20 insertions and (3) very rare EGFR mutations (very rare single point mutations, compound mutations, exon 18 deletions, exon 19 insertions).

RESULTS

Our study comprises the largest thus far reported real-world cohort of very rare EGFR single point and compound mutations treated with different systemic treatments. We validated higher efficacy of EGFR-TKI in comparison to chemotherapy in group 1 (uncommon), while most exon 20 insertions (group 2) were not EGFR-TKI responsive. In addition, we found TKI sensitivity of very rare point mutations (group 3) and of complex EGFR mutations containing exon 19 deletions or L858R mutations independent of the combination partner. Notably, treatment responses in group 3 (very rare) were highly heterogeneous. Co-occurring TP53 mutations exerted a non-significant trend for a detrimental effect on outcome in EGFR-TKI treated patients in groups 2 and 3 but not in group 1.

CONCLUSIONS

Based on our findings we propose a novel nNGM classification of uncommon EGFR mutations.

EGFR Testing Patterns and Detection of EGFR Exon 20 Insertions in the United States

INTRODUCTION

EGFR exon 20 insertions (EGFRex20ins) are a diverse set of mutations in NSCLC that are refractory to tyrosine kinase inhibitors. We describe real-world EGFRex20ins detection patterns in patients with advanced NSCLC in the United States.

METHODS

Data from 2011 to 2020 were extracted from the Flatiron Health electronic health record-derived deidentified database.

RESULTS

Among 67,281 patients with advanced NSCLC and at least two clinic visits, 66.8% were tested for EGFR mutations, of whom 13.9% tested positive. Of these, 4.9% had EGFRex20ins. The median time from NSCLC diagnosis to the first positive EGFRex20ins test result was 23 days, including 9 days of laboratory testing time. The EGFRex20ins were reported in 0.6% to 1.0% of all patients with advanced NSCLC and account for 3.9% to 5.3% of all EGFR mutations. During the study period, reverse transcription-polymerase chain reaction testing rates decreased whereas next-generation sequencing rates increased both in overall and among patients with tumors positive for EGFRex20ins. Tissue was the most common sample type used for EGFR and EGFRexon20ins detection (81.1% and 84.9%, respectively), whereas blood sampling for EGFRexon20ins detection increased from 0% (2011) to 37.2% (2020). For 23.7% of patients with EGFRex20ins, treatment was initiated before receiving the first positive EGFRex20ins test result, with therapies including immuno-oncology agents as the most common treatment type from 2017 to 2020.

CONCLUSIONS

EGFR testing and detection of EGFRex20ins in patients with NSCLC have increased slightly over time with the increasing use of next-generation sequencing. The current late-stage development of EGFRex20ins-targeted therapy is driving a need for more efficient testing.

EGFR exon 20 Insertion NSCLC and Response to Platinum-Based Chemotherapy

INTRODUCTION

In classical EGFR mutant non-small-cell lung cancer (NSCLC), EGFR tyrosine kinase inhibitor (TKI) therapy yields better outcomes than platinum-based chemotherapy. However, EGFR exon 20 insertion (ex20ins) NSCLC is relatively resistant to currently available EGFR TKIs. Though platinum-based chemotherapy is the frontline standard of care for EGFR ex20ins NSCLC, its efficacy is not fully described.

STUDY DESIGN

A retrospective, single-center, case series METHODS: Patients were identified through an electronic research database at a single institution and included if they had advanced EGFR ex20ins NSCLC, received platinum-based chemotherapy for metastatic disease, and had scans evaluable for response. Each patient's demographics, tumor characteristics, and clinical course were recorded. Treatment response was evaluated using RECIST v1.1 criteria, and the PFS was calculated by the Kaplan-Meier method.

RESULTS

Among 27 patients identified with EGFR ex20ins NSCLC at our institution, 18 (67%) received platinum-based chemotherapy for metastatic disease and had scans evaluable for response. These patients received platinum-based chemotherapy in the first-line (N = 17, 94%) and second-line settings (N = 1, 6%). The objective response rate (ORR) to platinum-based chemotherapy was 39% (7 of 18 patients; 95% confidence interval [CI] 16-61). The median PFS with platinum-based chemotherapy was 7.1 months (95% CI, 6.3 -13.7), and the median overall survival was 3.2 years (95% CI, 1.92 - NR).

CONCLUSIONS

The efficacy of platinum-based chemotherapy in EGFR ex20ins NSCLC is similar to that expected for TKI sensitive EGFR mutant NSCLC. Novel agents designed to specifically target ex20ins mutant EGFR should additionally improve outcomes.

Prevalence of Epidermal Growth Factor Receptor Exon 20 Insertion Mutations in Non-small-Cell Lung Cancer in Europe: A Pragmatic Literature Review and Meta-analysis

Background

Information on the epidemiology of uncommon EGFR mutations including exon 20 insertions amongst non-small-cell lung cancer (NSCLC) is lacking.

Objective

The objective of this pragmatic literature review (PLR) and meta-analysis was to generate robust prevalence and incidence estimates based on ranges of exon 20 insertion mutations reported in the literature.

Materials and methods

Searches of MEDLINE, Embase, congresses and reference lists for articles published from 2013 in key European countries of interest (Belgium, France, Germany, Italy, The Netherlands, Spain, Sweden, Switzerland, United Kingdom) were performed. Articles were reviewed against pre-specified criteria and their quality was appraised using a published checklist. Prevalence estimates were synthesised by random-effects meta-analyses.

Results

Eighty unique studies of moderate-to-high quality were included in the PLR. The meta-analysed prevalence for EGFR mutations was 12.5% (95% confidence interval [CI]: 11.0, 14.1) in any stage NSCLC and 14.8% (12.8, 17.1) in advanced/metastatic NSCLC. The prevalence of exon 20 insertions was 0.7% (0.4, 1.1) in any stage NSCLC and 6.1% (4.0, 9.4) in any stage EGFR-positive NSCLC. Mutation status was primarily measured using direct sequencing or a combination of methods. One study reporting exon 20 insertions in advanced/metastatic disease was identified, which reported a prevalence of 0.5% in overall NSCLC and 4.0% in EGFR-positive NSCLC.

Conclusions

EGFR exon 20 insertion mutations are rare in NSCLC. There is a high unmet need in patients with exon 20 insertions, including effective therapies. Prospective cohort studies are needed to better clinically characterise these patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11523-022-00868-z.

Targeted Therapies for Lung Cancer Patients With Oncogenic Driver Molecular Alterations

Lung cancer has traditionally been classified by histology. However, a greater understanding of disease biology and the identification of oncogenic driver alterations has dramatically altered the therapeutic landscape. Consequently, the new classification paradigm of non-small-cell lung cancer is further characterized by molecularly defined subsets actionable with targeted therapies and the treatment landscape is becoming increasingly complex. This review encompasses the current standards of care for targeted therapies in lung cancer with driver molecular alterations. Targeted therapies for EGFR exon 19 deletion and L858R mutations, and ALK and ROS1 rearrangements are well established. However, there is an expanding list of approved targeted therapies including for BRAF V600E, EGFR exon 20 insertion, and KRAS G12C mutations, MET exon 14 alterations, and NTRK and RET rearrangements. In addition, there are numerous other oncogenic drivers, such as HER2 exon 20 insertion mutations, for which there are emerging efficacy data for targeted therapies. The importance of diagnostic molecular testing, intracranial efficacy of novel therapies, the optimal sequencing of therapies, role for targeted therapies in early-stage disease, and future directions for precision oncology approaches to understand tumor evolution and therapeutic resistance are also discussed.

Radical Resection for Second EGFR-mutated Primary Lung Cancer Following Immune Checkpoint Inhibitor Monotherapy for Stage IV Lung Adenocarcinoma

A 78-year-old woman with multiple lung nodules, epithelial growth factor receptor (EGFR) exon 20 insertion mutations, and diagnosed with advanced lung adenocarcinoma (cT4N3M1a, stage IVA), was referred to our hospital. She received immune checkpoint inhibitor (ICI) therapy. The therapy showed remarkable antitumor effects; only a single nodule remained in the right upper lobe. The nodule was diagnosed as adenocarcinoma through a biopsy. We subsequently performed right upper lobectomy for multiple primary lung cancer (MPLC). The surgical specimen contained EGFR exon 19 deletion mutations and not exon 20 insertion mutations.

Prevalence of targeted therapy-related genetic variations in NSCLC and their relationship with clinicopathological characteristics

Background

Non-small cell lung cancer (NSCLC) is the most common cancer type in China. Targeted therapies have been used to treat NSCLC for two decades, which is only suitable for a subgroup of patients with specific genetic variations. The aim of this study was to investigate the prevalence of genetic variations leading to sensitivity or resistance to targeted therapies in NSCLC, and their relationship with clinicopathological characteristics of the patients.

Methods

Tumor samples were collected from 404 patients who were diagnosed to have NSCLC and underwent surgery, transthoracic biopsy, bronchoscopy biopsy, or pleural aspiration in Sichuan Provincial People’s Hospital from January 2019 to March 2020. Commercial amplification-refractory mutation system kits were used to detect targeted therapy-related genetic variations in those tumor samples. The prevalence of genetic variations and their relationship with patient clinicopathological characteristics were analyzed using statistical software, followed by subgroup analysis.

Results

In all, 50.7% of the NSCLC patients had sensitive genetic variations to anti-EGFR therapies, and 4.9% of those patients had co-existing resistant genetic variations. Fusions in ALK, ROS1, or RET were found in 7.7% of the patients, including 2 patients with co-existing EGFR exon 19 deletion or L858R. EGFR exon 19 deletion and L858R were more common in female patients and adenocarcinoma. Further subgroup analysis confirmed the observation in female patients in adenocarcinoma subgroup, and in adenocarcinoma in male patients. In addition, smokers were more likely to have squamous cell carcinoma and KRAS mutation and less likely to have EGFR L858R, which were also confirmed after standardization of gender except KRAS mutations.

Conclusion

Nearly half of the NSCLC patients were eligible for anti-EGFR treatments. In NSCLC, female gender and adenocarcinoma may indicate higher chance of EGFR exon 19 deletion or L858R, and smoking history may indicate squamous cell carcinoma and EGFR L858R.

EGFR Exon 20 Insertion Mutations in Sinonasal Squamous Cell Carcinoma

Recurrent epidermal growth factor receptor (EGFR)-activating mutations have been identified in a rare form of head and neck cancer known as sinonasal squamous cell carcinoma (SNSCC), a malignant disease with a 5-year mortality rate of ~40%. Interestingly, the majority of EGFR mutations identified in patients with primary SNSCC are exon 20 insertions (Ex20ins), which is in contrast to non-small-cell lung cancer (NSCLC), where the EGFR exon 19 deletion and L858R mutations predominate. These studies demonstrate that EGFR Ex20ins mutations are not exclusive to lung cancer as previously believed, but are also involved in driving SNSCC pathogenesis. Here we review the landscape of EGFR mutations in SNSCC, with a particular focus on SNSCC associated with inverted sinonasal papilloma (ISP), a benign epithelial neoplasm. Taking lessons from NSCLC, we also discuss potential new treatment options for ISP-associated SNSCC harbouring EGFR Ex20ins in the context of targeted therapies, drug resistance and precision cancer medicine. Moving forward, further basic and translational work is needed to delineate the biology of EGFR Ex20ins in SNSCC in order to develop more effective treatments for patients with this rare disease.

Chronicles of EGFR Tyrosine Kinase Inhibitors: Targeting EGFR C797S Containing Triple Mutations

Epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase widely expressed in many cancers such as non-small cell lung cancer (NSCLC), pancreatic cancer, breast cancer, and head and neck cancer. Mutations such as L858R in exon 21, exon 19 truncation (Del19), exon 20 insertions, and others are responsible for aberrant activation of EGFR in NSCLC. First-generation EGFR tyrosine kinase inhibitors (TKIs) such as gefitinib and erlotinib have clinical benefits for EGFR-sensitive (L858R and Del19) NSCLC patients. However, after 10-12 months of treatment with these inhibitors, a secondary T790M mutation at the gatekeeper position in the kinase domain of EGFR was identified, which limited the clinical benefits. Second-generation EGFR irreversible inhibitors (afatinib and dacomitinib) were developed to overcome this T790M mutation. However, their lack of selectivity toward wild-type EGFR compromised their clinical benefits due to serious adverse events. Recently developed third-generation irreversible EGFR TKIs (osimertinib and lazertinib) are selective toward driving mutations and the T790M mutation, while sparing wildtype EGFR activity. The latest studies have concluded that their efficacy was also compromised by additional acquired mutations, including C797S, the key residue cysteine that forms covalent bonds with irreversible inhibitors. Because second- and thirdgeneration EGFR TKIs are irreversible inhibitors, they are not effective against C797S containing EGFR triple mutations (Del19/T790M/C797S and L858R/T790M/C797S). Therefore, there is an urgent unmet medical need to develop next-generation EGFR TKIs that selectively inhibit EGFR triple mutations via a non-irreversible mechanism.

EGFR and HER2 exon 20 insertions in solid tumours: from biology to treatment

Protein tyrosine kinases of the human epidermal growth factor receptor family, including EGFR and HER2, have emerged as important therapeutic targets in non-small-cell lung, breast and gastroesophageal cancers, and are of relevance for the treatment of various other malignancies (particularly colorectal cancer). Classic activating EGFR exon 19 deletions and exon 21 mutations, and HER2 amplification and/or overexpression, are predictive of response to matched molecularly targeted therapies, translating into favourable objective response rates and survival outcomes. By comparison, cancers with insertion mutations in exon 20 of either EGFR or HER2 are considerably less sensitive to the currently available tyrosine kinase inhibitors and antibodies targeting these receptors. These exon 20 insertions are structurally distinct from other EGFR and HER2 mutations, providing an explanation for this lack of sensitivity. In this Review, we first discuss the prevalence and pan-cancer distribution of EGFR and HER2 exon 20 insertions, their biology and detection, and associated responses to current molecularly targeted therapies and immunotherapies. We then focus on novel approaches that are being developed to more effectively target tumours driven by these non-classic EGFR and HER2 alterations.

Amivantamab for the treatment of EGFR exon 20 insertion mutant non-small cell lung cancer

INTRODUCTION

Amivantamab is a monoclonal bispecific anti-EGFR-MET antibody that is the first targeted therapy to be approved for non-small cell lung cancer (NSCLC) patients harboring EGFR exon 20 insertion mutations following progression on chemotherapy, marking a watershed moment for a class of mutations which is generally associated with poor outcomes.

AREAS COVERED

In this article, we outline the drug profile of amivantamab compared with EGFR kinase inhibitors under evaluation in EGFR exon 20 insertion mutant NSCLC. We also review the efficacy and safety data reported from the CHRYSALIS phase I trial, which forms the basis of the recent approval of amivantamab.

EXPERT OPINION

Unlike small molecule EGFR kinase inhibitors, amivantamab has an extracellular mode of action and dual activity against EGFR and MET. It remains to be determined what role MET inhibition plays in toxicity and efficacy and whether dual target inhibition can delay the onset of drug resistance in these cancers. Due to its large molecular size, amivantamab is expected to have poor activity to treat brain metastases. Building on the clinical data so far, future trials that will evaluate combination treatments with brain-penetrant EGFR kinase inhibitors will be critical to move the drug toward a first-line treatment.

Quinoline–hydrazone hybrids as dual mutant EGFR inhibitors with promising metallic nanoparticle loading: rationalized design, synthesis, biological investigation and computational studies

A novel quinoline–hydrazone hybrid induced apoptosis in MCF-7 cells through dual mutant EGFR inhibition with promising metallic nanoparticle loading.

Cetuximab in Patients with Non-Small Cell Lung Cancer and EGFR Exon 20 Insertion Alterations

Epidermal Growth Factor Receptor (EGFR) exon 20 insertion alterations represent 4%-10% of all EGFR mutations in Non-Small Cell Lung Cancer (NSCLC) and result in resistance to standard EGFR-directed therapies. EGFR exon 20 insertions restrict the size of the kinase pocket, prohibiting the entry of approved EGFR kinase inhibitor drugs. Structural In Silico modeling also predicts that EGFR exon 20 insertion anomalies increase attractive electrostatic dimerization, hence stabilizing the activating dimer configuration. EGFR antibodies such as cetuximab that interfere with dimerization may lead to responses. We identified three non-smoking patients with NSCLC and EGFR exon 20 insertions treated with cetuximab-based therapy. All three patients demonstrated clinical benefit. A 58-year-old woman achieved prolonged stable disease lasting 9 months, while a 76-year-old woman and 38-year-old man maintained a partial response with progression-free survivals of 13 months and 32 months, respectively. In conclusion, cetuximab merits further investigation as it appears to be an additional promising therapy for overcoming EGFR exon 20 insertion-related resistance.

Discovery, Development, Inventions, and Patent Trends on Mobocertinib Succinate: The First-in-Class Oral Treatment for NSCLC with EGFR Exon 20 Insertions

The majority of lung cancers are non-small-cell lung cancer (NSCLC) having a low survival rate. Recent studies have indicated the involvement of epidermal growth factor receptor (EGFR) oncogene mutations like EGFR exon 20 insertions (EGFRex20ins) mutation among NSCLC patients. The response of patients of NSCLC with the EGFRex20ins mutation to the currently available EGFR inhibitor is negligible. Mobocertinib is the first oral treatment that has been approved by the USFDA, on 15 September 2021, to treat NSCLC with the EGFRex20ins mutation. This patent review discusses the inventions and patent literature of mobocertinib that will help the scientific community to develop additional and improved inventions related to mobocertinib. The structure of mobocertinib was first reported in 2015. Therefore, this article covered the patents/patent applications related to mobocertinib from 2015 to 25 October 2021. The patent search revealed 27 patents/patent applications related to compound, method of treatment, salt, polymorph, process, composition, and drug combinations of mobocertinib. The authors foresee an exciting prospect for developing a treatment for NSCLC with EGFRex20ins mutation, and other cancers employing a combination of mobocertinib with other approved anticancer agents. The inventions related to novel dosage forms, processes, and intermediates used in the synthesis of mobocertinib are also anticipated.

Spotlight on Amivantamab (JNJ-61186372) for EGFR Exon 20 Insertions Positive Non-Small Cell Lung Cancer

Non-small cell lung cancer (NSCLC) patients demonstrating sensitizing oncogenic driver mutations have derived clinical benefit from targeted therapy. EGFR mutations constitutively activate the signaling pathway, leading to prosurvival and antiapoptotic signals. Classic sensitizing EGFR mutations, such as exon 19 deletions and exon 21 L858R point mutations, respond well to tyrosine kinase inhibitors (TKIs). On the other hand, EGFR exon 20 in-frame insertions are observed in 4-12% of EGFR-mutated NSCLC and are resistant to targeted therapy with TKIs. In May 2021, the Federal Drug Administration (FDA) provided accelerated approval to amivantamab (Rybrevant) in adults with locally advanced or metastatic NSCLC with EGFR exon 20 insertion mutations after treatment with platinum-based chemotherapy. Here, we discuss properties of amivantamab, clinical trial results, and management of patients with EGFR exon 20 insertion mutated NSCLC.

Therapeutic advances in non-small cell lung cancer: Focus on clinical development of targeted therapy and immunotherapy

Lung cancer still contributes to nearly one-quarter cancer-related deaths in the past decades, despite the rapid development of targeted therapy and immunotherapy in non-small cell lung cancer (NSCLC). The development and availability of comprehensive genomic profiling make the classification of NSCLC more precise and personalized. Most treatment decisions of advanced-stage NSCLC have been made based on the genetic features and PD-L1 expression of patients. For the past 2 years, more than 10 therapeutic strategies have been approved as first-line treatment for certain subgroups of NSCLC. However, some major challenges remain, including drug resistance and low rate of overall survival. Therefore, we discuss and review the therapeutic strategies of NSCLC, and focus on the development of targeted therapy and immunotherapy in advanced-stage NSCLC. Based on the latest guidelines, we provide an updated summary on the standard treatment for NSCLC. At last, we discussed several potential therapies for NSCLC. The development of new drugs and combination therapies both provide promising therapeutic effects on NSCLC.

Treatment Outcomes and Safety of Mobocertinib in Platinum-Pretreated Patients With EGFR Exon 20 Insertion-Positive Metastatic Non-Small Cell Lung Cancer: A Phase 1/2 Open-label Nonrandomized Clinical Trial

IMPORTANCE

Metastatic non-small cell lung cancer (mNSCLC) with EGFR exon 20 insertion (EGFRex20ins) mutations is associated with a poor prognosis. Mobocertinib is an oral tyrosine kinase inhibitor designed to selectively target EGFRex20ins mutations.

OBJECTIVE

To evaluate treatment outcomes and safety of mobocertinib in patients with previously treated EGFRex20ins-positive mNSCLC.

DESIGN, SETTING, AND PARTICIPANTS

This 3-part, open-label, phase 1/2 nonrandomized clinical trial with dose-escalation/dose-expansion cohorts (28 sites in the US) and a single-arm extension cohort (EXCLAIM; 40 sites in Asia, Europe, and North America) was conducted between June 2016 and November 2020 (data cutoff date). The primary analysis populations were the platinum-pretreated patients (PPP) cohort and the EXCLAIM cohort. The PPP cohort included 114 patients with platinum-pretreated EGFRex20ins-positive mNSCLC who received mobocertinib 160 mg once daily from the dose-escalation (n = 6), dose-expansion (n = 22), and EXCLAIM (n = 86) cohorts. The EXCLAIM cohort included 96 patients with previously treated EGFRex20ins-positive mNSCLC (10 were not platinum pretreated and thus were excluded from the PPP cohort).

INTERVENTIONS

Mobocertinib 160 mg once daily.

MAIN OUTCOMES AND MEASURES

The primary end point of the PPP and EXCLAIM cohorts was confirmed objective response rate (ORR) assessed by independent review committee (IRC). Secondary end points included confirmed ORR by investigator, duration of response, progression-free survival, overall survival, and safety.

RESULTS

Among the PPP (n = 114) and EXCLAIM (n = 96) cohorts, the median (range) age was 60 (27-84) and 59 (27-80) years, respectively; most patients were women (75 [66%] and 62 [65%], respectively) and of Asian race (68 [60%] and 66 [69%], respectively). At data cutoff, median follow-up was 14.2 months in the PPP cohort (median 2 prior anticancer regimens; 40 [35%] had baseline brain metastases), with confirmed ORR of 28% (95% CI, 20%-37%) by IRC assessment and 35% (95% CI, 26%-45%) by investigator assessment; median duration of response by IRC assessment was 17.5 months (95% CI, 7.4-20.3). Median progression-free survival by IRC assessment was 7.3 months (95% CI, 5.5-9.2). Median overall survival was 24.0 months (95% CI, 14.6-28.8). In the EXCLAIM cohort, median follow-up was 13.0 months, with confirmed ORR by IRC assessment of 25% (95% CI, 17%-35%) and by investigator assessment of 32% (95% CI, 23%-43%). The most common treatment-related adverse events were diarrhea and rash.

CONCLUSIONS AND RELEVANCE

In this open-label, phase 1/2 nonrandomized clinical trial, mobocertinib was associated with clinically meaningful benefit in patients with previously treated EGFRex20ins-positive mNSCLC, with a manageable safety profile.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02716116.

The storm of NGS in NSCLC diagnostic-therapeutic pathway: How to sun the real clinical practice

The increasing number of approved drugs along with next generation sequencing (NGS) technologies look out as potential revolution of biomolecular characterization of non-small-cell lung cancer (NSCLC). Nevertheless, several aspects impact on success rate of NGS in clinical practice: a multidisciplinary approach and thorough knowledge of strengths and limits of each technologic diagnostic tool are required. Crucial preliminary step is the selection of the best available sample before testing, aware of clinical condition and setting of disease. Genomic data should be than integrated in the clinical context and matched with available therapeutic options; Molecular Tumor Boards (MTB) are worldwide emerging interdisciplinary groups implemented to transfer the impact of precision medicine in clinical practice. In order to guarantee equity in treatment, these considerations should find their application widely and rapidly. Aim of this review is offering an overview of emerging biomarkers, relative upcoming targeted drugs, and new diagnostic chances with an authors' perspective about a real-life diagnostic-therapeutic algorithm useful for daily clinical practice.

Comparative clinical outcomes for patients with advanced NSCLC harboring EGFR exon 20 insertion mutations and common EGFR mutations

INTRODUCTION

Real-world clinical outcomes in patients with advanced NSCLC harboring EGFR exon 20 insertion (exon20ins) mutations have not been extensively studied. We conducted a retrospective cohort study to assess the clinical outcomes of EGFR exon20ins compared with common EGFR (cEGFR) mutations.

METHODS

Adults with advanced NSCLC harboring any EGFR mutations in the NSCLC Flatiron registry (2011 through May 2020) were included. To compare the relative prognosis (prognostic value) of exon20ins vs cEGFR, real-world overall survival (rwOS) was the primary endpoint. Separately, to compare the relative response to tyrosine kinase inhibitor (TKI) treatment (predictive value), real-world progression-free survival (rwPFS) was the primary endpoint.

RESULTS

For the prognostic value analysis, 3014 patients with EGFR mutant NSCLC (cEGFR, n = 2833; EGFR exon20ins, n = 181) were eligible. The median (95% CI) rwOS was 16.2 (11.04-19.38) months in the EGFR exon20ins cohort vs 25.5 (24.48-27.04) months in the cEGFR cohort (adjusted HR, 1.75 [1.45-2.13]; p < 0.0001); 5-year rwOS was 8% and 19%, respectively. For the predictive value analysis, 2825 patients received TKI treatment and were eligible (cEGFR, n = 2749; EGFR exon20ins, n = 76). The median (95% CI) rwPFS from start of the first TKI was 2.9 (2.14-3.91) months in the EGFR exon20ins cohort vs 10.5 (10.05-10.94) months in the cEGFR cohort (adjusted HR, 2.69 [2.05-3.54]; p < 0001). Among patients with EGFR exon20ins, the most common prescribed first-line therapy was platinum-based chemotherapy (61.3%) followed by EGFR TKIs (21.5%); second-line treatments were varied, with no clear standard of care.

CONCLUSIONS

Patients with EGFR exon20ins have poor prognosis and receive little benefit from EGFR TKI treatment. More effective therapies are needed in this difficult-to-treat population.

Epidermal growth factor receptor exon 20 insertion variants in non-small cell lung cancer patients

Epidermal growth factor receptor (EGFR) exon 20 insertions occur rarely among different cancer types, with the highest frequency reported among non-small-cell lung cancer (NSCLC) patients, particularly adenocarcinomas (ADCs). Exon 20 insertions fall back in the tyrosine kinase domain, and can be clustered into two principal groups represented by in frame insertions and three to 21 bp (corresponding to 1-7 amino acids) duplications within amino acids 762 and 774. The identification of these alterations is key for an adequate management of NSCLC patients due to the possibility to treat these patients with specific targeted therapies. Next generation sequencing (NGS) technology, able to detect several hotspot gene mutations for different patients simultaneously, is the best detection approach due to its higher sensitivity and specificity compared to other techniques. Here we reviewed the principal biological characteristics, the main detection technologies and treatment options for NSCLC patients harbouring EGFR exon 20 insertions.

Case Report: Osimertinib Followed by Osimertinib Plus Bevacizumab, Personalized Treatment Strategy for a Lung Cancer Patient With a Novel EGFR Exon 20 Insertion D770_N771insGT and Multiple Brain Metastases

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (EGFR-TKIs) are the standard of care for non–small cell lung cancer (NSCLC) patients with EGFR exon 19 deletion and L858R mutations. However, no EGFR TKI has been approved for NSCLC patients harboring insertion mutations in EGFR exon 20 (EGFRex20ins), a subgroup of uncommon EGFR mutations resistant to first-generation EGFR TKIs. This unmet clinical challenge is further complicated by disease progression due to brain metastases (BMs), which limits the use of EGFR TKIs with low intracranial activity. Osimertinib, a third-generation EGFR TKI with high CNS activity, has demonstrated superior efficacy as a first-line treatment for EGFR-mutant NSCLC with or without BM. The VEGF pathway is a key mediator of cancer metastasis and resistance to EGFR TKIs. Accumulating evidence has demonstrated that the addition of anti-VEGF agents to EGFR TKIs provides an alternative treatment option for the clinical management of EGFR-mutant NSCLC. We herein report an NSCLC case with a novel EGFRex20ins mutation D770_N771insGT and multiple brain metastases who briefly responded to first-line osimertinib treatment and subsequently achieved prolonged disease control with osimertinib plus bevacizumab as second-line treatment. Our case suggests that osimertinib in combination with bevacizumab may be an effective option for NSCLC patients with specific EGFRex20ins mutations and brain metastases.

Paradigm shift in the management of metastatic nonsmall cell lung cancer

BACKGROUND

Lung cancer is one of the leading causes of cancer mortality in the United States. The use of precision medicine in the past 10 years has significantly changed the therapeutic landscape of lung cancer. Management of advanced nonsmall cell lung cancer (NSCLC) has transitioned from a chemotherapeutic approach to targeted treatments and immunotherapeutic agents. Several tyrosine kinase inhibitors (TKIs) have been approved for patients with targeted mutations and patients who do not have driver mutations; immunotherapy has been recently approved as frontline therapy, which has resulted in marked improvement in overall survival and added a new tool in our armamentarium.

AIMS

The purpose of this review is to highlight recent advancements in diagnostic approach and management strategies in patients with metastatic NSCLC.

MATERIALS AND METHODS

A literature search was conducted on Medline (via PubMed) and National Comprehensive Cancer Network Guidelines using the keywords "precision diagnosis," "advanced non-small cell lung cancer," "target therapies," and "immunotherapy."

CONCLUSION

The use of next-generation sequencing has significantly changed our understanding of molecular oncogenic mechanisms of lung cancer. These advancements have created a paradigm shift in the treatment strategies of metastatic lung cancer from primarily chemotherapeutic approach to increasing use of targeted therapies and immune checkpoint inhibitors (ICI) leading to better survival rates and lesser toxicity.

Trends in kinase drug discovery: targets, indications and inhibitor design

The FDA approval of imatinib in 2001 was a breakthrough in molecularly targeted cancer therapy and heralded the emergence of kinase inhibitors as a key drug class in the oncology area and beyond. Twenty years on, this article analyses the landscape of approved and investigational therapies that target kinases and trends within it, including the most popular targets of kinase inhibitors and their expanding range of indications. There are currently 71 small-molecule kinase inhibitors (SMKIs) approved by the FDA and an additional 16 SMKIs approved by other regulatory agencies. Although oncology is still the predominant area for their application, there have been important approvals for indications such as rheumatoid arthritis, and one-third of the SMKIs in clinical development address disorders beyond oncology. Information on clinical trials of SMKIs reveals that approximately 110 novel kinases are currently being explored as targets, which together with the approximately 45 targets of approved kinase inhibitors represent only about 30% of the human kinome, indicating that there are still substantial unexplored opportunities for this drug class. We also discuss trends in kinase inhibitor design, including the development of allosteric and covalent inhibitors, bifunctional inhibitors and chemical degraders.

Mobocertinib: First Approval

Mobocertinib (EXKIVITY™) is a first-in-class EGFR tyrosine kinase inhibitor being developed for the treatment of EGFR exon 20 insertion (EGFRex20ins) -positive non-small cell lung cancer (NSCLC). Based on efficacy in patients whose disease had progressed on or after platinum-based therapy in a phase I/II trial, mobocertinib was recently granted accelerated approval in the USA in this indication. The drug is also being assessed for marketing approval in various other countries and territories including the EU and China. This article summarizes the milestones in the development of mobocertinib leading to this first approval in the USA for locally advanced or metastatic EGFRex20ins-positive NSCLC that has progressed on or after platinum-based chemotherapy.

Therapeutic exploration of uncommon EGFR exon 20 insertion mutations in advanced non-small cell lung cancer: breaking through brambles and thorns

BACKGROUND

EGFR exon 20 insertion (EGFR ex20ins) mutations account for about 10-12% of all EGFR-mutated tumors, which are usually associated with primary drug resistance to conventional EGFR-TKI therapy and worse survival outcomes, and are currently a major problem for clinicians in clinical management. In recent years, with the rapid improvement of sequencing technology and careful review of clinical data, investigators have gained a deeper understanding and clearer cognition of the clinicopathological features and molecular mechanisms of these EGFR ex20ins mutations.

PURPOSE

The aim of this study was to systemically review the molecular structure and clinical characteristics of EGFR ex20ins mutations, and focus on summarizing the latest data of emerging therapies (including novel small-molecule EGFR-TKI drugs, specific monoclonal antibodies, novel drugs targeting other mechanisms, and immunotherapy) for those patients.

CONCLUSION

Advances in overcoming these systemic challenges have greatly accelerated the development of new drugs targeting EGFR ex20ins, and are committed to designing more rational combination therapies to overcome or delay the emergence of drug resistance, ultimately improve the prognosis of such uncommon mutant populations.

EGFR Exon 20 Insertion in Metastatic Non-Small-Cell Lung Cancer: Survival and Clinical Efficacy of EGFR Tyrosine-Kinase Inhibitor and Chemotherapy

EGFR exon 20 insertions are rare genetic alterations in non-small-cell lung cancers (NSCLCs) that are usually unresponsive to approved EGFR tyrosine kinase inhibitors (TKIs). In this paper, we describe the clinical characteristics, efficacy of EFGR TKIs and chemotherapy, and resulting survival in this population. We retrospectively collected patients with EGFR exon 20 insertions (Exon20ins) from 11 French genetic platforms and paired them (1:2 ratio) with classic Exon 19/21 EGFR mutation patients (controls). Between 2012 and 2017, 35 Exon20ins patients were included. These patients were younger at diagnosis than the controls. All Exon20ins patients who were treated with first-line EGFR TKIs (n = 6) showed progressive disease as the best tumor response. There was no significant difference in the tumor response or the disease control rate with first-line platinum-based chemotherapy between the two groups. A trend towards shorter overall survival was observed in Exon20ins vs. controls (17 months (14-not reach(NR) 95% confidence interval(CI) vs. 29 months (17-NR 95%CI), p = 0.09), respectively. A significant heterogeneity in amino acid insertion in EGFR exon 20 was observed. EGFR exon 20 insertions are heterogeneous molecular alterations in NSCLC that are resistant to classic EGFR TKIs, which contraindicates their use as a first-line treatment.

Clinical characteristics of advanced non-small cell lung cancer patients with EGFR exon 20 insertions

Epidermal growth factor receptor (EGFR) exon 20 insertion mutations (Exon20ins) account for 4–12% of all EGFR mutations in non-small cell lung cancer (NSCLC) patients. Data on the differences in clinical characteristics between patients with Exon20ins and major mutations (M-mut) such as exon 19 deletion and L858R are limited. We retrospectively reviewed advanced NSCLC patients with EGFR mutations, who were treated with systemic therapy between January 2011 and December 2019. We identified 23 patients with Exon20ins and 534 patients with M-mut. In Exon20ins patients, the median age was 60 (range 27–88) years, and females and never-smokers were predominant. Clinical characteristics were similar in the two groups. In Exon20ins patients, 17 patients received platinum doublet as first-line therapy, and the overall response rate (ORR) and median progression-free survival (mPFS) were 11.8% and 8.9 months. Additionally, seven patients received conventional EGFR-tyrosine kinase inhibitors (TKIs), and eight patients anti-PD-1 antibodies in any-line therapy. ORR and mPFS of EGFR-TKIs and anti-PD-1 antibodies were 0%, 2.2 months and 25%, 3.1 months, respectively. Overall survival was significantly shorter in Exon20ins patients than in M-mut patients (29.3 vs. 43.4 months, p = 0.04). The clinical outcomes in Exon20ins patients were not satisfactory compared to M-mut patients.

The immune microenvironment in EGFR- and ERBB2-mutated lung adenocarcinoma

Background

Targeted therapies have improved survival and quality of life for patients with non-small-cell lung cancer with actionable driver mutations. However, epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 gene (HER2, also known as ERBB2) exon 20 insertions (Ex20mut) are characterized by a poor response to currently approved tyrosine kinase inhibitors and immunotherapies. The underlying immune biology is not well understood.

Materials and methods

We carried out messenger RNA expression profiling of lung adenocarcinomas (ADCs) with ERBB2 (n = 19) and EGFR exon 20-insertion mutations (n = 13) and compared these to tumors with classical EGFR mutations (n = 40, affecting EGFR exons 18, 19 or 21) and EGFR/ERBB2 mutation-negative lung ADC (EGFR/ERBB2wt, n = 26) focusing on immunologically relevant transcripts. Tumor-infiltrating immune cells were estimated from gene expression profiles.

Results

Cytotoxic cells were significantly lower in EGFR-mutated tumors regardless of the affected exon, while Th1 cells were significantly lower in EGFR-Ex20mut compared to EGFR/ERBB2wt tumors. We assessed the differentially expressed genes of ERBB2-Ex20mut and EGFR-Ex20mut tumors compared to EGFR-Ex18/19/21mut and EGFR/ERBB2wt tumors. Of these, the genes GUSB, HDAC11, IFNGR2, PUM1, RASGRF1 and RBL2 were up-regulated, while a lower expression of CBLC, GBP1, GBP2, GBP4 and MYC was observed in all three comparison groups. The omnibus test revealed 185 significantly (FDR = 5%) differentially expressed genes and we found these four most significant gene expression changes in the study cohort: VHL and JAK1 were overexpressed in ERBB2-Ex20mut and EGFR-Ex20mut tumors compared to both EGFR-Ex18/19/21mut and EGFR/ERBB2wt tumors. RIPK1 and STK11IP showed the highest expression in ERBB2-Ex20mut tumors.

Conclusions

Targeted gene expression profiling is a promising tool to read out the characteristics of the tumor microenvironment from routine diagnostic lung cancer biopsies. Significant immune reactivity and specific immunosuppressive characteristics in ERBB2-Ex20mut and EGFR-Ex20mut lung ADC with at least some degree of immune infiltration support further clinical evaluation of immune-modulators as partners of immune checkpoint inhibitors in such tumors.

•

Gene expression profiling to characterize the tumor microenvironment is feasible using diagnostic lung cancer biopsies.

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EGFR exon 20-mutated tumors show a higher expression of VHL and an immunologic ‘colder’ phenotype than EGFR/ERBB2wt tumors.

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ERBB2 exon 20-mutated tumors show an overexpression of RIPK1 and STK11IP and a reduction of cytotoxic natural killer cells.

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Drugs targeting these alterations are potential partners of checkpoint blockade in exon 20-mutated non-small-cell lung cancer.

Prognostic model of long-term advanced stage (IIIB-IV) EGFR mutated non-small cell lung cancer (NSCLC) survivors using real-life data

BACKGROUND

There is a lack of useful diagnostic tools to identify EGFR mutated NSCLC patients with long-term survival. This study develops a prognostic model using real world data to assist clinicians to predict survival beyond 24 months.

METHODS

EGFR mutated stage IIIB and IV NSCLC patients diagnosed between January 2009 and December 2017 included in the Spanish Lung Cancer Group (SLCG) thoracic tumor registry. Long-term survival was defined as being alive 24 months after diagnosis. A multivariable prognostic model was carried out using binary logistic regression and internal validation through bootstrapping. A nomogram was developed to facilitate the interpretation and applicability of the model.

RESULTS

505 of the 961 EGFR mutated patients identified in the registry were included, with a median survival of 27.73 months. Factors associated with overall survival longer than 24 months were: being a woman (OR 1.78); absence of the exon 20 insertion mutation (OR 2.77); functional status (ECOG 0-1) (OR 4.92); absence of central nervous system metastases (OR 2.22), absence of liver metastases (OR 1.90) or adrenal involvement (OR 2.35) and low number of metastatic sites (OR 1.22). The model had a good internal validation with a calibration slope equal to 0.781 and discrimination (optimism corrected C-index 0.680).

CONCLUSIONS

Survival greater than 24 months can be predicted from six pre-treatment clinicopathological variables. The model has a good discrimination ability. We hypothesized that this model could help the selection of the best treatment sequence in EGFR mutation NSCLC patients.

Osimertinib in EGFR-Mutated Lung Cancer: A Review of the Existing and Emerging Clinical Data

The use of epidermal growth factor receptor (EGFR) inhibitors such as osimertinib has improved outcomes and quality of life for patients with EGFR-mutated non-small cell lung cancer (NSCLC). Osimertinib has become the preferred EGFR tyrosine kinase inhibitor (TKIs) for patients with these mutations after demonstrating superior efficacy compared to first generation EGFR TKIs, such as erlotinib and gefitinib. More recently osimertinib has also shown to be beneficial in patients with resectable NSCLC harboring EGFR mutations irrespective of whether they received adjuvant chemotherapy or not. The drug is now FDA approved in this setting. With osimertinib being used more commonly in earlier stage and front-line settings, we are more likely to see patients who develop resistance to this drug. The aim of this review is to provide a comprehensive review of the data with osimertinib in EGFR mutation positive NSCLC, potential resistance mechanisms and an overview of key ongoing clinical trials.

Establishment and genetic characterization of cell lines derived from proliferating nasal polyps and sinonasal inverted papillomas

To better understand the pathogenesis of nasal polyps (NPs) and sinonasal inverted papillomas (SIPs), we aimed to establish cell lines from fresh tissues of NPs and SIPs and characterize them. Primary cell cultures were obtained from two NP tissues (NP2 and NP3) and one SIP tissue (IP4). All the cells were polygonal in shape, expressed cytokeratin 14, and had normal diploid chromosome status. HPV58 DNA was detected in NP3. To obtain immortal primary cells, NP2 and IP4 cells were transduced with a combination of mutant CDK4, cyclinD1 and TERT. These cells were thereafter named NP2/K4DT and IP4/K4DT, respectively. HPV58-positive NP3 cells were transduced with TERT alone, the resulting cells named NP3/T. Phenotypic and genotypic identity of original tissues and derived cells was investigated. All the cell cultures with transgenes were confirmed to be derived from their parental cells and primary tumor tissues by analysis of short tandem repeats (STR) and maintained in vitro growth, genetic profiles and gene expression characteristics of the primary cells. These virtually immortalized cells, as well as the primary cells, have potential as in vitro models for studying the pathogenesis of NPs and SIPs and for preclinical study to develop new therapeutic agents.

Real-world implementation of sequential targeted therapies for EGFR-mutated lung cancer

Background:

Epidermal growth factor receptor-mutated (EGFR⁺) non-small-cell lung cancer (NSCLC) patients failing tyrosine kinase inhibitors (TKI) can benefit from next-line targeted therapies, but implementation is challenging.

Methods:

EGFR⁺ NSCLC patients treated with first/second-generation (1G/2G) TKI at our institution with a last follow-up after osimertinib approval (February 2016), were analyzed retrospectively, and the results compared with published data under osimertinib.

Results:

A total of 207 patients received erlotinib (37%), gefitinib (16%) or afatinib (47%). The median age was 66 years, with a predominance of female (70%), never/light-smokers (69%). T790M testing was performed in 174/202 progressive cases (86%), positive in 93/174 (53%), and followed by osimertinib in 87/93 (94%). Among the 135 deceased patients, 94 (70%) received subsequent systemic treatment (43% chemotherapy, 39% osimertinib), while 30% died without, either before (4%) or after progression, due to rapid clinical deterioration (22%), patient refusal of further therapy (2%), or severe competing illness (2%). Lack of subsequent treatment was significantly (4.5x, p < 0.001) associated with lack of T790M testing, whose most frequent cause (in approximately 50% of cases) was also rapid clinical decline. Among the 127 consecutive patients with failure of 1G/2G TKI started after November 2015, 47 (37%) received osimertinib, with a median overall survival of 36 months versus 24 and 21 months for patients with alternative and no subsequent therapies (p = 0.003).

Conclusion:

Osimertinib after 1G/2G TKI failure prolongs survival, but approximately 15% and 30% of patients forego molecular retesting and subsequent treatment, respectively, mainly due to rapid clinical deterioration. This is an important remediable obstacle to sequential TKI treatment for EGFR⁺ NSCLC. It pertains also to other actionable resistance mechanisms emerging under 1G/2G inhibitors or osimertinib, whose rate for lack of next-line therapy is similar (approximately 35% in the FLAURA/AURA3 trials), and highlights the need for closer monitoring alongside broader profiling of TKI-treated EGFR⁺ NSCLC in the future.

Lung cancer

Lung cancer is one of the most frequently diagnosed cancers and the leading cause of cancer-related deaths worldwide with an estimated 2 million new cases and 1·76 million deaths per year. Substantial improvements in our understanding of disease biology, application of predictive biomarkers, and refinements in treatment have led to remarkable progress in the past two decades and transformed outcomes for many patients. This seminar provides an overview of advances in the screening, diagnosis, and treatment of non-small-cell lung cancer and small-cell lung cancer, with a particular focus on targeted therapies and immune checkpoint inhibitors.

EGFR-mutant NSCLC: emerging novel drugs

PURPOSE OF REVIEW

Despite the significant advances in EGFR-mutant nonsmall cell lung cancer (NSCLC), some challenges remain. One of the permanent and inevitable issues is the emergence of acquired resistance. Therefore, blocking the activation of EGFR pathway and overcoming drug resistance with novel agents are still in high demand. Here, we review the development of novel drugs in EGFR-mutant, advanced NSCLC, including targeting EGFR exon 20 insertion (EGFR20ins), and novel role of epidermal growth factor receptor, tyrosine kinase inhibitor (EGFR-TKIs) in early-stage NSCLC.

RECENT FINDINGS

EGFR-TKIs as adjuvant therapy or neoadjuvant therapy in patients with early-stage NSCLC with EGFR-sensitizing mutations have shown promising efficacy. The resistance mechanisms of third-generation EGFR-TKIs can be divided into two types: EGFR dependent and EGFR independent. Several clinical trials have demonstrated that the addition of MET inhibitors to EGFR-TKIs was an effective option for patients who had acquired resistance to EGFR-TKIs caused by hepatocyte growth factor receptor gene (MET) amplification or overexpression. Novel compounds that selectively and potently inhibit EGFR20ins are being investigated in phase III studies.

SUMMARY

A better characterization and understanding of resistance mechanisms to first-line osimertinib and adjuvant osimertinib is helpful to guide further treatment.

Analysis of EGFR, KRAS, and PIK3CA gene mutation rates and clinical distribution in patients with different types of lung cancer

Background

To analyze and evaluate EGFR, KRAS, and PIK3CA gene mutation rates and clinical distribution in patients with different types of lung cancer

Method

A total of 221 lung cancer patients treated in our hospital between January 2016 and June 2019 were enrolled. Tissue and whole blood samples were collected and analyzed to determine the mutation status of EGFR, KRAS, and PIK3CA genes. The gene exon mutation rates were determined. Relevant clinical data, such as age, gender, tumor sample type, treatment method, pathologic type, and lung cancer stage were recorded and statistically analyzed.

Results

The EGFR gene mutation rates in exons E18-E21 were 2.3%, 17.6%, 3.6%, and 20.4%, respectively. E18, E19, and E20 mutations were commonly detected in adenosquamous carcinoma, and E21 mutations were commonly detected in adenocarcinoma. Mutations in exons E18-E21 were frequently detected in patients with lung cancer stages IA, IB, IIA, or IIB, respectively. The KRAS gene mutation rate in lung cancer patients in exon E2 was higher in whole blood and tissue samples than other exon mutations, while the KRAS gene mutation rate in exons E2 and E3 was significantly higher in patients with lung cancer stages IIB and IA, respectively. PIK3CA gene mutations in exons E9 and E20 occurred in patients < 60 years of age. Exon E9-positive mutations were more common in men or patients with squamous cell carcinoma, while exon E20-positive mutations were more common in females.

Conclusion

The EGFR, KRAS, and PIK3CA gene exon mutation rates differ and were shown to be correlated with different clinical indicators, which have significance in clinical treatment.

Activity and Safety of Mobocertinib (TAK-788) in Previously Treated Non-Small Cell Lung Cancer with EGFR Exon 20 Insertion Mutations from a Phase I/II Trial

Mobocertinib, an oral epidermal growth factor receptor (EGFR) inhibitor targeting EGFR gene mutations, including exon 20 insertions (EGFRex20ins), in non-small cell lung cancer, was evaluated in a phase I/II dose-escalation/expansion trial (ClinicalTrials.gov NCT02716116). Dose escalation identified 160 mg/d as the recommended phase 2 dose and maximum tolerated dose. Among 136 patients treated with 160 mg/d, the most common any-grade treatment-related adverse events (TRAE; >25%) were diarrhea (83%), nausea (43%), rash (33%), and vomiting (26%), with diarrhea (21%) the only grade ≥3 TRAE >5%. Among 28 EGFRex20ins patients treated at 160 mg/d, the investigator-assessed confirmed response rate was 43% (12/28; 95% confidence interval, 24%-63%) with median duration of response of 14 months (5.0-not reached) and median progression-free survival of 7.3 months (4.4-15.6). Mobocertinib demonstrated antitumor activity in patients with diverse EGFRex20ins variants with a safety profile consistent with other EGFR inhibitors. SIGNIFICANCE: No oral EGFR-targeted therapies are currently approved for patients with EGFRex20ins NSCLC. Mobocertinib demonstrated antitumor activity with manageable toxicity in patients with advanced EGFRex20ins NSCLC in this study, supporting additional development of mobocertinib in this patient population.See related commentary by Pacheco, p. 1617.This article is highlighted in the In This Issue feature, p. 1601.

Targeting the Epidermal Growth Factor Receptor in EGFR-Mutated Lung Cancer: Current and Emerging Therapies

Epidermal growth factor receptor-targeting tyrosine kinase inhibitors (EGFR TKIs) are the standard of care for patients with EGFR-mutated metastatic lung cancer. While EGFR TKIs have initially high response rates, inherent and acquired resistance constitute a major challenge to the longitudinal treatment. Ongoing work is aimed at understanding the molecular basis of these resistance mechanisms, with exciting new studies evaluating novel agents and combination therapies to improve control of tumors with all forms of EGFR mutation. In this review, we first provide a discussion of EGFR-mutated lung cancer and the efficacy of available EGFR TKIs in the clinical setting against both common and rare EGFR mutations. Second, we discuss common resistance mechanisms that lead to therapy failure during treatment with EGFR TKIs. Third, we review novel approaches aimed at improving outcomes and overcoming resistance to EGFR TKIs. Finally, we highlight recent breakthroughs in the use of EGFR TKIs in non-metastatic EGFR-mutated lung cancer.