Epidermal Growth Factor Receptor Ex20ins Research Articles

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

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

Abstract CT152: FURTHER: A global study to evaluate furmonertinib in patients with EGFR mutant NSCLC including uncommon EGFR mutations

Abstract Background: Furmonertinib (AST2818) is an oral, highly brain-penetrant, and broadly active mutation-selective epidermal growth factor receptor (EGFR) inhibitor engineered for broad activity and selectivity across EGFR mutations (mts) (Musib et al., NACLC 2022). Furmonertinib is approved in China for first-line advanced NSCLC with EGFR Ex19del or L858R mts based on the positive Phase 3 study (FURLONG) versus gefitinib. Furmonertinib has also demonstrated promising interim efficacy and safety in patients (pts) with NSCLC with EGFR exon 20 insertion (ex20ins) mts with a confirmed overall response rate (ORR) of 78.6% (n=28) by blinded independent central review (BICR) with a preliminary median duration of response (DoR) of 15.2 months in the front-line setting (FAVOUR study; see Han et al., WCLC 2023). Furmonertinib recently obtained FDA Breakthrough Therapy Designation for the treatment of pts with advanced NSCLC with EGFR ex20ins mts. P-loop and αC-helix Compressing (PACC) mts represent another subset of uncommon EGFR mts (Robichaux et al., 2021) that are similar to ex20ins mts in narrowing the drug-binding pocket; including G719X, S768I, E709X, L747X, V774M. Preclinical data indicating that furmonertinib is potent in models harboring EGFR PACC mts will be presented at this meeting (Nilsson et al., Abstract #4174). Developing efficacious, well-tolerated, and CNS-penetrant medicines for NSCLC pts with EGFR ex20ins mts and PACC mts remains an unmet need. Methods: FURTHER (FURMO-002) is the first global trial evaluating furmonertinib in NSCLC pts with EGFR and HER2 mts in North America, Europe, and the Asia-Pacific. FURTHER is a phase 1b, open-label, multicenter study in which pts will be treated orally with furmonertinib daily. For Stage 1 dose-escalation, the primary endpoint is incidence and severity of adverse events, including dose limiting toxicities and has been completed. For Stage 2 dose expansion, approximately 120 pts will be enrolled across 4 expansion cohorts. Stage 2 Cohorts 1-3 dose expansion cohorts will enroll pts with previously treated, locally advanced or metastatic NSCLC pts with either EGFR ex20ins mts, HER2 ex20ins mts, or EGFR activating mts, respectively. Cohorts 1-3 allow enrollment of pts with prior EGFR or HER2-directed therapy. Stage 2 Cohort 4 will enroll EGFR TKI-naïve NSCLC pts with EGFR PACC mts. Key inclusion criteria include documented EGFR or HER2 mts by local testing and measurable disease per RECIST v1.1. Stage 2 primary endpoint is ORR using RECIST v1.1. Key secondary endpoints include progression-free survival and overall survival. Stage 2 enrollment is ongoing. Clinical trial information: NCT05364073. Citation Format: Xiuning Le, Alexander Spira, Shirish Gadgeel, Yan Yu, Yanqiu Zhao, Ying Cheng, Jonathan Riess, Oscar Juan-Vidal, Bo Gao, Kiyotaka Yoh, Martin Forster, Satoru Kitazono, Hidetoshi Hayashi, David Planchard, Yong Jiang, Jack Huang, Nichole Baio, Marcin Kowanetz, Shirley Wang, William Leung, Jerry Y. Hsu, Jie Wang. FURTHER: A global study to evaluate furmonertinib in patients with EGFR mutant NSCLC including uncommon EGFR mutations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT152.

[Expert consensus on clinical practice of EGFR exon20 insertion detection in non-small cell lung cancer in China (2024 edition)].

About 82% of the Chinese lung cancer population is non-small cell lung cancer(NSCLC), and the epidermal growth factor receptor (EGFR) gene is the most common driver mutation in the Chinese lung cancer population (51.7%-54.4%). In recent years, the rapid development and wide application of targeted therapies, especially EGFR tyrosine kinase inhibitors, have significantly improved the survival time and quality of life of Chinese lung cancer patients. EGFR exon20 insertion (EGFR ex20ins) accounts for 0.3%-2.9% in NSCLC patients in China. Recently, several tyrosine kinase inhibitors have been approved for the therapy of EGFR ex20ins NSCLCs. The variety variants and high molecular heterogeneity of EGFR ex20ins NSCLCs asks for more accurate detection methods, and clinical routine detection process needs to be further standardized. On account to the practical questions of EGFR ex20ins detection, this consensus was finally reached based on the combination of literature, expert experience and internal discussion among committee members, in the hope of providing the guide for standardizing the EGFR ex20ins detection.

Abstract 3263: VEGFA mediates traditional EGFR-TKI resistance in non-small cell lung cancer with EGFR exon 20 insertions

Abstract Background: Epidermal growth factor receptor (EGFR) exon 20 insertions (Ex20ins) accounted for 4%-12% of EGFR mutations and showed primary resistance to EGFR tyrosine kinase inhibitors (EGFR-TKIs) which is an urgent issue to be solved. In our previous studies, we found that antiangiogenetic therapy had certain advantages for patients with Ex20ins in the real-world practice. Previous research showed the tumor microenvironment has been associated with resistance to targeted therapy in sensitive mutations. However, the mechanism of resistance of EGFR-TKIs and the advantage of antiangiogenetic therapy in patients with EGFR Ex20ins were still unclear. Methods: In this study, patients with EGFR exon 19 deletion (19del), exon 21 p.L858R (21L858R), and Ex20ins were collected to identify the efficacy of EGFR-TKIs. Stable cell lines expressing were established and used to compare signaling pathway activation. Matrigel angiogenesis assay was conducted in different cell lines. Next, we evaluated the efficacy of various treatments combined with antiangiogenetic agents or not in mouse models. Results: We collected 23 patients with EGFR sensitive mutations and Ex20ins, respectively, and found Ex20ins presented primary resistance to TKIs and poor survival outcomes. Based on the RNA sequence of stable cell lines, it was found that Ex20ins had a higher level of VEGFA expression and enriched in MAPK pathway compared to EGFR 19del and 21L858R. Immunohistochemical studies also revealed that a higher level of VEGFA expression was observed in a cohort of NSCLC patients with Ex20ins mutation compared with 19del or L858R. Matrigel angiogenesis assay has shown consistent result that Ex20ins promoted angiogenesis in vivo. Further experiments in mouse models identified that in the group of Osimertinib, mobocertinib alone, chemotherapy alone, mobocertinib or chemotherapy combination with bevacizumab, Osimertinib achieved the worst efficacy and additional utility of antiangiogenetic agents had a more favorable efficacy. Conclusion: Our study highlights the potential of VEGFA as a mechanism of resistance to EGFR-TKIs and induces immunosuppression microenvironment in NSCLC with Ex20ins. Furthermore, the findings suggested that antiangiogenetic therapy could be a promising therapeutic approach. Keywords: VEGFA, targeted therapy, resistance, EGFR exon 20 insertions, non-small cell lung cancer Citation Format: Yaning Yang, Chengming Liu, Guangjian Yang, Haiyan Xu, Siyu Lei, Yan Wang. VEGFA mediates traditional EGFR-TKI resistance in non-small cell lung cancer with EGFR exon 20 insertions [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3263.

Abstract 6504: Exploratory analysis using serial cell-free DNA in patients treated with amivantamab in non-small cell lung cancer with EGFR exon 20 insertion mutations

Abstract Introduction: Epidermal growth factor receptor (EGFR) exon 20 insertion (ex20 ins) mutation showed limited clinical activity with conventional EGFR tyrosine kinase inhibitors (TKIs). Amivantamab is the first bispecific antibody to be approved for the treatment of metastatic non-small cell lung cancer (NSCLC) with EGFR ex20ins mutation. However, limited data is available in terms of predictive biomarkers and the resistance mechanism. In this study, we conducted an exploratory analysis to elucidate a genomic landscape using circulating tumor DNA (ctDNA) from plasma samples. Patients and Methods: This study include result from 79 blood samples, which has been prospectively collected from 27 EGFR ex20ins mutated NSCLC patients (confirmed by either tissue or plasma-based test) who were treated with amivantamab. ctDNAs were obtained from plasma, which was serially collected at baseline, after 2 cycles of treatment, 2 cycles prior to the treatment discontinuation, and at the time point of disease progression. Guardant OMNI panel (Guardant Health, CA, USA) was used for the genomic profiling. Results: The median follow-up duration was 5.8 months (range 2.7-12.7). The overall response rate was 40.7% (95% confidence interval [CI] 24.5-59.2, n=11), and median progression-free survival was 5.8 months (95% CI 3.9-15.9) with a median duration of response of 9.8 months (95% CI, 7.3-NA). Patients with EGFR ex20ins not detected from ctDNA at baseline (n=10) showed significantly longer PFS compared to patients with EGFR ex20ins identified at baseline plasma sample (n=17) (14.6 vs 3.9 months; hazard ratio [HR] 0.40, 95% CI 0.17-0.95, P<0.05).The most common concurrent somatic variations at baseline were TP53 (62.9%), TERT (18.5%), ATM (18.5%). Longer median PFS was observed in patients without EGFR amplification (n=18) compared to patients with concurrent EGFR amplification (n=9) (11.1 vs. 2.5 months; HR 0.30, 95% CI 0.11-0.77, P <0.05). The presence of plasma EGFR ex20ins at C2D15 predicted poor PFS (17.8 vs 2.7 months; HR 0.17, 95% CI 0.06-0.47, P <0.01), regardless of baseline its presence or absence. Based on the paired analysis using baseline and at the timepoint of disease progression, putative resistance mechanism to amivantamab was identified in 14 patients (60.8%), which were PDGFRB (28.5%), followed by PTEN (21.4%), CHEK2 (21.4%). Conclusions: This study provides a comprehensive longitudinal ctDNA analysis in patients with EGFR ex20ins mutant NSCLC who were treated with amivantamab. Our results suggested that the presence of ctDNA for EGFR ex20ins mutation and co-alteration with EGFR amplification at baseline might be related to the clinical outcomes of amivantamab. Citation Format: Geun-Ho Park, Sehhoon Park, Hyen-Ae Jung, Jong-Mu Sun, Jin Seok Ahn, Myung-Ju Ahn, Se-Hoon Lee. Exploratory analysis using serial cell-free DNA in patients treated with amivantamab in non-small cell lung cancer with EGFR exon 20 insertion mutations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6504.

Mobocertinib: Mechanism of action, clinical, and translational science.

Epidermal growth factor receptor (EGFR) exon 20 insertion (ex20ins) mutations represent ~6%-12% of all EGFR-mutated non-small cell lung cancer (NSCLC) cases. First-, second-, and third-generation tyrosine kinase inhibitors (TKIs) have limited clinical activity against EGFR ex20ins mutations. Mobocertinib is a first-in-class oral EGFR TKI that selectively targets in-frame EGFR ex20ins mutations in NSCLC; accelerated approval in the United States was granted for the treatment of adult patients with locally advanced or metastatic NSCLC with EGFR ex20ins mutations whose disease has progressed on or after platinum-based chemotherapy. Accelerated approval was based on the results from the three-part, open-label, multicenter, pivotal phase I/II nonrandomized clinical trial (NCT02716116) that enrolled 114 patients with locally advanced or metastatic EGFR ex20ins mutation-positive NSCLC who were previously treated with platinum-based chemotherapy and received mobocertinib at the recommended dosage of 160 mg once daily. At the November 1, 2021, data cutoff date, the confirmed objective response rate per independent review committee (IRC) was 28%, median duration of response was 15.8 months, median progression-free survival per IRC was 7.3 months, and median overall survival was 20.2 months. The most common treatment-emergent adverse events were gastrointestinal- and skin-related. The phase III EXCLAIM-2 study evaluated mobocertinib versus chemotherapy as first-line therapy for locally advanced or metastatic EGFR ex20ins-positive NSCLC; however, the primary end point was not met, resulting in initiating voluntary withdrawal of mobocertinib worldwide. This mini-review article summarizes the mechanism of action, pharmacokinetic characteristics, key clinical trials, and clinical efficacy and safety data for mobocertinib.

First report of furmonertinib as a first-line treatment in advanced lung adenocarcinoma patients harboring EGFR exon 20 insertion mutations after the kinase domain αC-helix: Two case reports and a literature review

Rationale: Many studies have shown that first- and second-generation epidermal growth factor receptor tyrosine kinase inhibitors are less effective in patients with epidermal growth factor receptor (EGFR) exon 20 insertion (ex20ins) mutations. The efficacy of third-generation epidermal growth factor receptor tyrosine kinase inhibitors is still under investigation. Although new targeted tyrosine kinase inhibitors and monoclonal antibody-based agents have made significant advances in the treatment of epidermal growth factor receptor exon 20 insertion (EGFR ex20ins) mutation, the efficacy of these novel agents is not quite satisfactory. Platinum- and pemetrexed-based chemotherapy remains the standard first-line treatment for patients harboring EGFR ex20ins mutation. Patient concerns: We report for the first time 2 Chinese patients diagnosed with advanced lung adenocarcinoma with EGFR ex20ins mutations after analysis of the αC-helix sequence by next-generation sequencing. Both patients were treated with furmonertinib as the first-line therapy. Interventions: The first case included a 38-year-old female who had an EGFR ex20ins mutation (p.S768_D770dupSVD). After 1 month of treatment with furmonertinib, her symptoms of pain and cough were significantly alleviated. She achieved a partial response according to response evaluation criteria in solid tumors.[1] The final progression-free survival was 8.13 months. The second case included a 40-year-old male who had an EGFR ex20ins mutation (p.N771_P772insVal). He had a good response to furmonertinib and exhibited stable disease according to response evaluation criteria in solid tumors with a progression-free survival of 10.90 months. Outcomes: Both patients experienced significant improvement in symptoms and prolonged survival after furmonertinib was used as first-line treatment. Side effects were limited but manageable. Conclusion: The present study indicates that furmonertinib may be a first-line treatment option for patients with non-small cell lung cancer harboring EGFR ex20ins mutation.

Abstract B153: Resistance mechanisms to mobocertinib in treating NSCLC with EGFR exon 20 insertion mutations

Abstract Background: Mobocertinib is an oral epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) that received FDA accelerated approval for non-small cell lung cancer (NSCLC) with EGFR exon 20 insertion (ex20ins) mutations, based on data from a pivotal phase 1/2 study of mobocertinib (NCT02716116). In platinum-pretreated patients (pts) with EGFR ex20ins NSCLC (N=114), the overall response rate (ORR) was 28%, median duration of response was 17.5 months, and median progression-free survival was 7.3 months. Despite this encouraging clinical activity, de novo and acquired resistant mechanisms to mobocertinib remain largely unknown. Methods: Tumor samples and circulating tumor DNA (ctDNA) samples were obtained from platinum-pretreated pts with EGFR ex20ins+ NSCLC treated with mobocertinib (NCT02716116) and subjected to next-generation sequencing (NGS) analyses. CtDNA was collected at baseline, cycle 3 day 1 (C3D1) and progression per protocol. Tumor growth assay was performed in BaF3 cells and patient-derived xenograft models to evaluate efficacy of combination therapies to overcome resistance. Results: At baseline, in tumor (n=56), the combined presence of BRAF and PIK3CA mutations alone (n=9) or together with copy number gains (CNV) in EGFR, MYC, CDK4, or CCND1 (n=19) was significantly associated with inferior ORR to mobocertinib with odd ratios of ‘infinity’ (p=0.045) and 13.21 (p=0.0047), respectively. Individual co-occurring gene mutations and CNV were not significantly associated with differential clinical outcomes. Longitudinal analysis of paired tumor-blood samples at baseline and C3D1 showed that 22 out of 55 pts (40%) achieved clearance at C3D1, including 81.2% (13/16) of PR pts, 50% of SD pts, and 20% of PD pts. CtDNA was also used to assess emerging mutations after mobocertinib progression after at least 5 months of treatment (n=18). TP53 (n=11) and acquired secondary EGFR (n=5) were the most common genes with emerging variants, including EGFR T790M (n=4) and D379E (n=1). With this observation, T790M was engineered in Ba/F3 cells in the context of EGFR ex20ins mutations (H773_V774insNPH and 769_D770insASV). T790M did confer resistance to mobocertinib in vitro, and to all EGFR TKIs tested including osimertinib. In patient-derived xenograft models (H773_V774insNPH and 769_D770insASV), the combination of mobocertinib plus the bispecific monoclonal antibody amivantamab demonstrated greater antitumor activity than either agent alone. Conclusions: Our results indicate that bypass pathway alterations are associated with de novo resistance whereas T790M emergence mediates acquired resistance to mobocertinib. Future research is warranted to determine the potential clinical benefits of combination strategies in patients with EGFR ex20ins+ NSCLC. Citation Format: Xiuning Le, Monique Nilsson, Sampurna Chatterjee, Zhenqiang Su, Junqin He, Hibiki Udagawa, Xiaoxing Yu, Alissa Poteete, Qian Huang, John V Heymach, Sylvie Vincent. Resistance mechanisms to mobocertinib in treating NSCLC with EGFR exon 20 insertion mutations [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr B153.

Structural Mechanism and Inhibitors Targeting EGFR Exon 20 Insertion (Ex20ins) Mutations.

Epidermal growth factor receptor (EGFR) targeted therapy is one of the most important and effective strategies to combat EGFR mutant nonsmall-cell lung cancer (NSCLC). However, a substantial number of patients bearing EGFR exon 20 insertion (Ex20ins) mutations respond poorly to common EGFR targeted therapies. This clinical need remained unmet until recently, when the EGFR Ex20ins mutation inhibitor mobocertinib was approved by the FDA. Despite this progress, the structural mechanisms of EGFR Ex20ins mutation resistance and characterization of inhibitor binding modes have not been systematically summarized. Herein, we analyze the structural mechanisms for ligand binding and resistance and summarize recent developments for the reported inhibitors of EGFR Ex20ins mutations. Furthermore, this Perspective aims to provide insights for the design of the next generation of EGFR Ex20ins inhibitors.

A plain language summary of the results from the group of patients in the CHRYSALIS study with EGFR exon 20 insertion-mutated non-small-cell lung cancer who received amivantamab.

This is a plain language summary of an article published in the Journal of Clinical Oncology in 2021. It describes the first results from 1 group of patients in the phase 1 CHRYSALIS study with epidermal growth factor receptor (EGFR) exon 20 insertion (ex20ins) mutations. This part of the CHRYSALIS study (called cohort D) investigated the bispecific antibody amivantamab (brand name RYBREVANT®) in patients with non-small-cell lung cancer (NSCLC) with an EGFR ex20ins mutation. EGFR mutations are one of the most common causes of NSCLC tumors, with EGFR ex20ins mutations being more common among people of Asian descent. Patients who took part in this study had cancer that could not be removed by surgery, and whose cancer had worsened after receiving other forms of treatment, such as chemotherapy. Typically, patients with this type of mutation are difficult to treat or do not experience treatment response with commonly used therapies that target EGFR. The CHRYSALIS study took place between May 27, 2016, and June 8, 2020, in select hospitals in the USA, Japan and South Korea. In cohort D, amivantamab showed promising results, with an overall response rate of 40%. This means that 4 of every 10 patients in CHRYSALIS cohort D had tumors that shrank or were no longer measurable. Clinical Trial Registration: NCT02609776 (the CHRYSALIS Phase I Study) (ClinicalTrials.gov).

Safety, Tolerability, and Antitumor Activity of Zipalertinib Among Patients With Non-Small-Cell Lung Cancer Harboring Epidermal Growth Factor Receptor Exon 20 Insertions.

Although several agents targeting epidermal growth factor receptor (EGFR) exon 20 insertions (ex20ins) have recently been approved by the US Food and Drug Administration, toxicities related to the inhibition of wild-type (WT) EGFR are common with these agents and affect overall tolerability. Zipalertinib (CLN-081, TAS6417) is an oral EGFR tyrosine kinase inhibitor (TKI) with a novel pyrrolopyrimidine scaffold leading to enhanced selectivity for EGFR ex20ins-mutant versus WT EGFR with potent inhibition of cell growth in EGFR ex20ins-positive cell lines. This phase 1/2a study of zipalertinib enrolled patients with recurrent or metastatic EGFR ex20ins-mutant non-small-cell lung cancer (NSCLC) previously treated with platinum-based chemotherapy. Seventy-three patients were treated with zipalertinib at dose levels including 30, 45, 65, 100, and 150 mg orally twice a day. Patients were predominantly female (56%), had a median age of 64 years, and were heavily pretreated (median previous systemic therapies 2, range 1-9). Thirty six percent of patients had received previous non-ex20ins EGFR TKIs and 3/73 (4.1%) patients received previous EGFR ex20ins TKIs. The most frequently reported treatment-related adverse events of any grade included rash (80%), paronychia (32%), diarrhea (30%), and fatigue (21%). No cases of grade 3 or higher drug-related rash or diarrhea were observed at 100 mg twice a day or below. Objective responses occurred across all zipalertinib dose levels tested, with confirmed partial response (PR) observed in 28/73 (38.4%) response-evaluable patients. Confirmed PRs were seen in 16/39 (41%) response-evaluable patients at the dose of 100 mg twice a day. Zipalertinib has encouraging preliminary antitumor activity in heavily pretreated patients with EGFR ex20ins-mutant NSCLC, with an acceptable safety profile, including low frequency of high-grade diarrhea and rash.

Characteristics, treatment patterns, and clinical outcomes in patients with advanced non-small cell lung cancer harboring EGFR exon 20 insertions.

Epidermal growth factor receptor (EGFR) exon 20 insertions (ex20ins) are associated with poor prognosis and resistance to traditional therapies in patients with non-small cell lung cancer (NSCLC). We aimed to elucidate the characteristics and treatment patterns to improve outcomes among this population in Taiwan. Patients with advanced or recurrent NSCLC harboring EGFR ex20ins from 2011 to 2021 were reviewed. The treatment groups were classified as platinum-based chemotherapy (PtC), EGFR tyrosine kinase inhibitor (TKI), and others. The response to therapy, objective response rate (ORR), disease control rate (DCR), overall survival (OS), progression-free survival (PFS), and factors associated with survival were analyzed. Among the 71 patients, most were never-smoking males with stage IVB adenocarcinoma. The most common first-line (1L) regimen was PtC, followed by TKI. The most common second-line (2L) regimen was TKI. The median PFS of 1L treatment was 5.03 months, and the median OS was 18.43 months. Compared with that of TKI, 1L PtC use was associated with a higher ORR (26.3% vs. 9.1%) and DCR (60.5% vs. 18.2%) and a longer PFS (5.37 vs. 3.13 months, p = 0.044). PFS was also significantly longer in the 2L PtC group than in the 2L TKI group (4.73 vs. 2.25 months, p = 0.047). No patients receiving an immune checkpoint inhibitor-based regimen exhibited a therapeutic response. This study demonstrated the heterogeneous clinical characteristics and treatment pattern of NSCLC patients with EGFR ex20ins, underscoring the need for more effective therapies for this distinct molecular subtype.

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

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

[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.

Comparative effectiveness of mobocertinib and standard of care in patients with NSCLC with EGFR exon 20 insertion mutations: An indirect comparison

IntroductionMobocertinib is a novel, first-in-class, irreversible, oral epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) designed to selectively target in-frame EGFR exon 20 insertions (ex20ins). Comparative effectiveness data for mobocertinib versus real-world treatments are lacking in this rare population. This study compared data for mobocertinib reported in a Phase I/II single-arm clinical trial with an external control group consisting of patients who received available treatment in the real-world setting in the United States (US). Materials and MethodsThe mobocertinib group included platinum-pretreated patients with advanced EGFR ex20ins non-small cell lung cancer (NSCLC) receiving mobocertinib 160 mg QD in an ongoing, single-arm, phase 1/2 clinical trial (NCT02716116; n = 114). The real-world data (RWD) group included platinum-pretreated patients with advanced EGFR ex20ins-mutant NSCLC from the Flatiron Health database (n = 50). Inverse probability treatment weighting based on the propensity score method controlled for potential confounding between groups. Confirmed overall response rate (cORR), progression-free survival (PFS), and overall survival (OS) were compared between groups. ResultsAfter weighting, baseline characteristics were balanced. Patients in the RWD group received EGFR TKI (20 %), immuno-oncology therapy (40 %), or any regimens containing chemotherapy (40 %) in the second- or later-line setting. In the mobocertinib and RWD groups, respectively, cORR was 35.1 % and 11.9 % (odds ratio: 3.75 [95 % confidence interval (CI): 2.05, 6.89]); median PFS was 7.3 and 3.3 months (hazard ratio [HR]: 0.57 [95 % CI: 0.36, 0.90]); and median OS was 24.0 and 12.4 months (HR: 0.53 [95 % CI: 0.33, 0.83]) after weighting. DiscussionMobocertinib showed substantially improved outcomes versus an external control group using available therapies in platinum-pretreated patients with EGFR ex20ins-mutant NSCLC. In the absence of comparative evidence from randomized trials, these findings help elucidate potential benefits of mobocertinib in this rare population.

[Advances in the Treatment of EGFR Exon 20ins Mutant NSCLC].

Lung cancer has become one of the most dangerous cancers to human health and the mortality rate is the highest among all the causes of cancer death. Non-small cell lung cancer (NSCLC) accounts for about 80%-85% of lung cancer. Chemotherapy is the main treatment for advanced NSCLC, but the 5-year survival rate is low. Epidermal growth factor receptor (EGFR) mutations are the most common driver mutations in lung cancer, but EGFR exon 20 insertions (EGFR ex20ins) mutation belongs to one of the rare mutations, accounting for about 4%-10% of overall EGFR mutations, thus around 1.8% of advanced NSCLC patients. In recent years, targeted therapies represented by EGFR tyrosine kinase inhibitors (TKIs) have become an important treatment option for patients with advanced NSCLC, however, NSCLC patients with EGFR ex20ins mutation are not sensitive to most of EGFR-TKIs treatments. Currently, some of the targeted drugs for EGFR ex20ins mutation have achieved significant efficacy, while some of them are still under clinical investigation. In this article, we will describe various treatment methods for EGFR ex20ins mutation and their efficacy.
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Mobocertinib (TAK-788) in EGFR Exon 20 Insertion+ Metastatic NSCLC: Patient-Reported Outcomes from EXCLAIM Extension Cohort.

Mobocertinib, an oral, first-in-class epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor selective for EGFR exon 20 insertions (ex20ins), achieved durable responses in adults with previously treated EGFR ex20ins+ metastatic non-small cell lung cancer (mNSCLC) in the EXCLAIM extension cohort of a phase 1/2 study (N = 96; NCT02716116). We assessed patient-reported outcomes (PROs) with mobocertinib 160 mg once daily (28-day cycles) in EXCLAIM (N = 90) with the European Organisation for Research and Treatment of Cancer Core Quality-of-Life Questionnaire (EORTC QLQ-C30) v3.0, lung cancer module (QLQ-LC13), EuroQol-5 Dimensions-5 Levels (EQ-5D-5L) questionnaire, and selected PRO Version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE) questionnaire. Median treatment duration was 6.8 (range, 0.0-18.8) months (median follow-up: 13.0 [0.7-18.8] months; data cutoff: 1 November 2020). Clinically meaningful improvements in lung cancer symptoms measured by EORTC QLQ-LC13 were observed for dyspnea (54.4% of patients), cough (46.7%), and chest pain (38.9%), evident at cycle 2 and throughout treatment (least-squares mean [LSM] changes from baseline: dyspnea, -3.2 [p = 0.019]; cough, -9.3 [p < 0.001]; chest pain, -8.2 [p < 0.001]). EORTC QLQ-C30 results indicated no statistically significant changes in global health status/quality of life (LSM change from baseline: -1.8 [p = 0.235]). On symptom scores, significant worsening from baseline was observed for diarrhea (LSM change from baseline: +34.1; p < 0.001) and appetite loss (+6.6; p = 0.004), while improvements were observed for dyspnea (LSM change from baseline: -5.1 [p = 0.002]), insomnia (-6.5 [p = 0.001]), and constipation (-5.7 [p < 0.001]). EQ-5D-5L health status was maintained. Common PRO-CTCAE symptoms were diarrhea, dry skin, rash, and decreased appetite (mostly low grade); in the first 24 weeks of treatment, 64.4% of patients had worsening diarrhea frequency and 67.8% had worsening dry skin severity. Overall, PROs with mobocertinib showed clinically meaningful improvement in lung cancer-related symptoms, with health-related quality of life maintained despite changes in some adverse event symptom scales.

Emerging therapies for non-small cell lung cancer harboring EGFR exon 20 insertion mutations: narrative review

Epidermal growth factor receptor (EGFR) exon 20 insertion mutations (ex20ins) are uncommon in non-small cell lung cancer (NSCLC). These mutations are generally resistant to first-generation EGFR tyrosine kinase inhibitors, unlike common EGFR mutations, including exon 19 deletions or exon 21 L858R point mutation. The development of effective targeted therapies for NSCLC harboring EGFR ex20ins has been eagerly anticipated over the years. Recently, the therapeutic landscape of this subgroup of EGFR-mutant NSCLC patients has rapidly evolved due to the emergence of new drugs. In 2021, several novel agents, such as amivantamab and mobocertinib, have been approved by the US Food and Drug Administration for patients with advanced platinum-resistant NSCLC harboring EGFR ex20ins. In this review, we mainly focus on emerging therapies targeting NSCLC with EGFR ex20ins, as well as important ongoing clinical trials. Searches were conducted in PubMed and supplemented with recent conference proceedings in November 30th, 2021. Several novel emerging therapies showed favorable safety profile and promising anti-tumor activity in NSCLC patients with EGFR ex20ins in recent several clinical trials. There is still room for improvement in the treatment results of NSCLC harboring EGFR ex20ins. Future research should focus on the molecular heterogeneity in the size and location of distinct EGFR ex20ins, the mechanisms of acquired resistance to novel EGFR inhibitors, effective treatment that have good central nervous system penetrance, and the potential role of combination strategy.

Frequency, underdiagnosis, and heterogeneity of epidermal growth factor receptor exon 20 insertion mutations using real-world genomic datasets.

Epidermal growth factor receptor (EGFR) exon 20 insertion mutations (ex20ins) account for ≤ 12% of all EGFR-mutant nonsmall cell lung cancers. We analysed real-world datasets to determine the frequency of ex20ins variants, and the ability of polymerase chain reaction (PCR) and next-generation sequencing (NGS) to identify them. Three real-world United States NGS databases were used: GENIE, FoundationInsights, and GuardantINFORM. Mutation profiles consistent with in-frame EGFR ex20ins were summarized. GENIE, FoundationInsights, and GuardantINFORM datasets identified 180, 627, and 627 patients with EGFR ex20ins respectively. The most frequent insertion region of exon 20 was the near loop (~ 70%), followed by the far loop (~ 30%) and the helical (~ 3-6%) regions. GENIE, FoundationInsights, and GuardantINFORM datasets identified 41, 102, and 96 unique variants respectively. An analysis of variants projected that ~ 50% of EGFR ex20ins identified by NGS would have been missed by PCR-based assays. Given the breadth of EGFR ex20ins identified in the real-world US datasets, the ability of PCR to identify these mutations is limited. NGS platforms are more appropriate to identify patients likely to benefit from EGFR ex20ins-targeted therapies.

EP08.02-109 A Drug-Drug Interaction Study of Mobocertinib and Midazolam in Patients With Advanced Non-Small Cell Lung Cancer

Mobocertinib is an oral tyrosine kinase inhibitor designed to selectively target epidermal growth factor receptor (EGFR) exon 20 insertion (EGFR ex20ins) mutations in non-small cell lung cancer (NSCLC). In vitro studies indicated the potential for time-dependent inhibition and/or induction of cytochrome P450 (CYP) 3A after mobocertinib administration. Thus, a phase 1 drug-drug interaction study (NCT04051827) was conducted to assess the effect of repeat-dose administration of mobocertinib on the pharmacokinetics (PK) of midazolam, a sensitive CYP3A substrate.