Epidermal Growth Factor Receptor Alterations Research Articles

MARIPOSA: Can Amivantamab and Lazertinib Replace Osimertinib in the Front-Line Setting?

Osimertinib is the current first-line treatment for EGFR-mutated NSCLC, however, patients frequently relapse due to acquired resistance mutations. Amivantamab is a bispecific antibody against EGFR and MET alterations. Lazertinib is a tyrosine kinase inhibitor active against EGFR mutations including common resistance mutations. The MARIPOSA trial was designed to study if the combination of amivantamab plus lazertinib in untreated epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC) patients would provide improved progression-free survival. Here, we discuss the rationale for the study and the early results of MARIPOSA.

Abstract 3875: Glioblastoma mutational profiles drive cancer cell signaling and immune evasion

Abstract Glioblastoma multiforme (GBM) is the most common malignant brain tumor in adults with a median survival below two years. Characterization of GBM through gene expression profiling and DNA sequencing has identified disease subgroups and commonly altered genes and pathways, including alterations in the genes encoding neurofibromin-1 (NF1) and the epidermal growth factor receptor (EGFR). NF1 and EGFR are involved in receptor tyrosine kinase (RTK), RAS/MEK/ERK, and PI3K signaling, and together, are genetically altered in over 60% of adult GBMs. Interestingly, NF1 and EGFR alterations in GBM are almost always mutually exclusive. Here, we designed a multimodal approach integrating spatial proteomics, transcriptomics, and genomics to measure cell composition, immune cell function, cancer cell signaling, cellular spatial organization, gene expression, transcriptional subtypes, and genome alterations in 80 NF1 and EGFR altered human GBMs with extensively curated treatment and survival data. We quantified the spatial expression of 42 proteins in over 31 million single cells measuring RTK/RAS/PI3K and Rb signaling and features of the TME, including 23 cell types covering tumor cells, immune cells, and brain resident cells. In addition to tumor genotype labels, we classified each GBM tumor by its transcriptional subtype (i.e., mesenchymal, classical, or proneural). We identified genotype-phenotype associations in GBM including hyperactive RAS signaling cellular niches, a macrophage-rich TME, and an epithelial-mesenchymal signature in NF1 altered tumors and hyperactive RTK signaling and an immune desert TME in EGFR amplified tumors. Furthermore, we observed spatial heterogeneity in cancer cell signaling patterns suggestive of the presence of different tumor cell clones within different regions of each GBM tumor. Together, we identify several genotype-associated features of GBMs, reinforcing the value of integrating spatial multi-omic data for generation of genotype-driven therapeutic hypotheses, with implications for GBM genotype-based therapeutic stratification. Citation Format: Maryam Pourmaleki, Brian D. Greenstein, Caitlin J. Jones, Subhiksha Nandakumar, Daniel A. Navarrete, Smrutiben Mehta, Carl Campos, Travis J. Hollmann, Nicholas D. Socci, Tejus Bale, Sohrab P. Shah, Ingo K. Mellinghoff. Glioblastoma mutational profiles drive cancer cell signaling and immune evasion [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 3875.

EGFR amplification and EGFRvIII predict and participate in TAT-Cx43266-283 antitumor response in preclinical glioblastoma models.

Glioblastoma (GBM) commonly displays epidermal growth factor receptor (EGFR) alterations (mainly amplification and EGFRvIII) and TAT-Cx43266-283 is a Src-inhibitory peptide with antitumor properties in preclinical GBM models. Given the link between EGFR and Src, the aim of this study was to explore the role of EGFR in the antitumor effects of TAT-Cx43266-283. The effect of TAT-Cx43266-283, temozolomide (TMZ) and erlotinib (EGFR inhibitor) was studied in patient-derived GBM stem cells (GSCs) and murine neural stem cells (NSCs) with and without EGFR alterations, in vitro and in vivo. EGFR alterations were analyzed by Western blot (WB) and Fluorescence In Situ Hybridization (FISH) in these cells, and compared with Src activity and survival in GBM samples from TCGA. The effect of TAT-Cx43266-283 correlated with EGFR alterations in a set of patient-derived GSCs and was stronger than that exerted by TMZ and erlotinib. In fact, TAT-Cx43266-283 only affected NSCs with EGFR alterations, but not healthy NSCs. EGFR alterations correlated with Src activity and poor survival in GBM patients. Finally, tumors generated from NSCs with EGFR alterations, showed a decrease in growth, invasiveness and vascularization after treatment with TAT-Cx43266-283, which enhanced the survival of immunocompetent mice. Clinically relevant EGFR alterations are predictors of TAT-Cx43266-283 response and part of its mechanism of action, even in TMZ- and erlotinib-resistant GSCs. TAT-Cx43266-283 targets NSCs with GBM-driver mutations, including EGFR alterations, in an immunocompetent GBM model in vivo, suggesting a promising effect on GBM recurrence. Together, this study represents an important step towards the clinical application of TAT-Cx43266-283.

Molecular analysis for EGFR, ALK, and ROS1 alterations in over 3000 Indian patients with non-small-cell lung cancer: A retrospective observational study

Background: Accurate molecular testing in non-small-cell lung cancer (NSCLC) is of paramount importance for treatment, prediction, and prognostication. Objectives: We aimed to comprehensively describe the clinicopathological and molecular profile of Indian patients with NSCLC with regard to alterations in the epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), and c-ros oncogene 1 (ROS1). Materials and Methods: We conducted a retrospective analysis of lung tissue samples tested between January 2015 and December 2021 at the Metropolis Healthcare Limited global referral laboratory facility in Mumbai, Maharashtra, India. Testing was conducted for EGFR by real time reverse transcriptase polymerase chain reaction (RT-PCR) and Sanger sequencing, ALK by immunohistochemistry (IHC), ALK by fluorescence in situ hybridization (FISH), and c-ros oncogene 1 (ROS1) by FISH. We analyzed the positivity status and determined the trends in the results of the molecular targets in NSCLC cases. Results: Out of 3220 samples with malignancy, 1750 (54.3%) were tested for EGFR, out of which 510 (29.1%) were positive. The most common mutation detected was in exon 19 of EGFR (334/510, 65.5%), followed by exon 21 (164/510, 32.2%). A total of 1548 (48.1%) cases were tested for ALK by IHC, of which 125/1548 (8.1%) showed positivity, while among the 372/3220 (11.6%) cases tested for ALK by FISH, 29/372 (7.8%) were positive. In patients with squamous cell carcinoma, the ALK positivity rate by IHC was 5.3%. Of the 372 cases tested for ALK by FISH, 353 (94.9%) cases were tested for ALK by IHC as well; 98.9% concordance was observed for the positive cases. ROS1 testing was conducted in 370/3220 (11.5%) samples and showed a low positivity rate of 13/370 (3.5%). Conclusions: Indian patients with NSCLC have 29% EGFR positivity, 8.1% ALK positivity, and 3.5% ROS1 positivity, when tested with RT-PCR, IHC, and FISH, respectively. A detailed molecular analysis using next-generation sequencing (NGS) may help detect a higher number of molecular targets amenable to therapy.

Abstract C036: A Phase 1 Study to assess BDTX-1535, an oral EGFR inhibitor, in patients with Glioblastoma or Non-Small Cell Lung Cancer

Abstract Background: Epidermal growth factor receptor (EGFR) is a potent oncogene commonly altered in non-small cell lung cancer (NSCLC) and glioblastoma (rGBM). For NSCLC, EGFR tyrosine kinase activity can be driven by classical driver, intrinsic driver, and acquired resistance mutations. BDTX-1535 is an orally available, highly potent, brain penetrant, selective, irreversible small molecule tyrosine kinase inhibitor that targets all 3 classes of EGFR mutations. Preclinical data demonstrated the ability of BDTX-1535 to cross the blood-brain barrier and produce sustained inhibition of EGFR signaling. Methods: BDTX-1535-101 (NCT05256290) is a Phase 1, open-label, multicenter study to assess the safety, tolerability, pharmacokinetics (PK), central nervous system (CNS) activity, and preliminary antitumor activity of BDTX-1535 in locally advanced or metastatic NSCLC with or without CNS disease or recurrent GBM (rGBM). The primary objective is to determine the BDTX-1535 recommended Phase 2 dose (RP2D) based on the overall safety, PK, pharmacodynamic, and preliminary antitumor activity. The monotherapy dose escalation portion evaluates BDTX-1535 in patients with locally advanced/metastatic NSCLC harboring intrinsic driver EGFR mutations following standard of care or with acquired resistance EGFR mutations following a 3rd generation EGFR inhibitor in the 1st line setting, in addition to patients with rGBM expressing EGFR alterations who previously received available standard therapy of surgical resection followed by chemoradiotherapy and/or temozolomide (TMZ). A capsule-to-tablet bridging cohort and a food effect cohort will also be assessed. Following the establishment of a preliminary recommended Phase 2 dose (RP2D), the disease-specific expansion portion of the study will further evaluate the safety, tolerability, and preliminary antitumor effect of BDTX-1535. Cohorts include the following:1) advanced/metastatic NSCLC with intrinsic resistance EGFR mutations following up to 2 lines of therapy, one of which must be an EGFR inhibitor treatment, 2) advanced/metastatic NSCLC with acquired resistance EGFR mutation following a 3rd generation EGFR inhibitor in the first line setting, 3) rGBM with confirmed EGFR alterations with or without amplifications. NSCLC patients may enroll with or without CNS metastases and must not be known to express excluded resistance mutations such as EGFR T790M. BDTX-1535 will also be studied in combination with TMZ to assess safety, tolerability, and a recommended combination dose for the treatment of patients with newly diagnosed GBM harboring EGFR alterations. Enrollment was initiated in 2022 and dose escalation is almost complete. Initiation of the dose expansion cohorts of NSCLC patients with EGFR acquired resistance and intrinsic driver mutations after progression on prior EGFR inhibitor is planned for the second half of 2023. For additional information, please contact ClinicalTrials@bdtx.com. Citation Format: Helena Yu, Melissa Johnson, Jason T Henry, Alex Spira, Ji-Youn Han, Minal Barve, James Battiste, Iyad Alnahhas, DoHyun Nam, Jeffrey Edenfield, Balazs Halmos, Shinkyo Yoon, Tae Min Kim, Sudharshan Eathiraj, Julio Hajdenberg, Sergey Yurasov, Manmeet Ahluwalia, Patrick Wen. A Phase 1 Study to assess BDTX-1535, an oral EGFR inhibitor, in patients with Glioblastoma or Non-Small Cell Lung Cancer [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 C036.

PP71 Hospitalization Costs Associated With Advanced Non-Small Cell Lung Cancer In China: Real World Evidence From Jiangsu

IntroductionNon-small cell lung cancer (NSCLC) constitutes 85 percent of lung cancer diagnoses and poses an economic threat to the sustainability of healthcare services. This study was conducted to estimate hospitalization costs associated with advanced NSCLC without sensitizing EGFR (epidermal growth factor receptor) and ALK (anaplastic lymphoma kinase) alterations in China and explore the potential predictors.MethodsData linked with patients with advanced NSCLC (stage IIIB–IV) without sensitizing EGFR and ALK alterations were obtained from the electronic medical record system of one general hospital and one cancer hospital in Jiangsu province, China, ranging from January 2017 to December 2020. We excluded patients with lung metastases from tumors elsewhere in the body. The socio-demographic characteristics, disease-related characteristics, and hospitalization cost of eligible patients were extracted. We used the generalized linear model (GLM) to assess the potential influencing factors of hospitalization cost.ResultsPatients with advanced NSCLC (n=7,260) were included in this study. The median hospitalization cost of advanced NSCLC was USD11,540.47. The median hospitalization examination and test costs were USD1,539.46, and the median hospitalization drug cost was USD6,351.47. GLM results showed that patients aged 60 or older (95% Confidence Interval [CI]: -1019.1,128.6), who had no gene driver (95%CI: -1,681.6,-233.6) were more likely to have relatively lower hospitalization costs for advanced NSCLC. Patients treated in cancer hospital (95%CI: 1,329.1,2,620.0) and with non-squamous carcinoma (95%CI: 171.3, 1,235.4) may have higher hospitalization costs. Compared with Urban Employee Basic Medical Insurance, patients with free medical services (95%CI: 1,248.4,6,298.7) were associated with higher hospitalization costs. Patients with higher hospitalization frequency and longer length of hospital stay (p < 0.05) were linked to higher hospitalization costs.ConclusionsThe hospitalization costs linked to advanced NSCLC is considerable for patients, with drug costs accounting for the largest. More efforts still need to be made to alleviate the direct medical burden.

Abstract B033: Patterns of testing and survival for EGFR mutation and ALK abnormalities in advanced lung cancer at John Peter Smith Hospital

Abstract Background: There is paucity of literature regarding outcomes of patients treated for non-small cell lung cancer (NSCLC) at safety-net hospitals (Muslim et al., 2022). John Peter Smith (JPS) hospital is a safety-net hospital serving the needs of underserved population in north Texas. We evaluated testing patterns, prevalence of Epidermal Growth Factor Receptor (EGFR) mutations and Anaplastic Lymphoma Kinase (ALK) fusions in advanced NSCLC at JPS, and outcome measures of 1-, 3- and 5-year overall survival (OS) as compared to patients without these alterations. Methods: We used data from the JPS Oncology Registry and abstracted information from medical records. Eligible patients were diagnosed with stages IIIB-IV NSCLC and treated at JPS from 1/1/2017 to 12/31/2021. Patients were grouped into EGFR+, ALK+, both EGFR- and ALK-, test not ordered/completed (NT). A Kaplan Meier curve was used to assess the difference in post diagnosis survival time across testing status. The log rank test was then performed to assess if the survival distributions were significantly different. To further assess the impact of EGFR and ALK results on patient death three cox proportional hazard models were generated assessing 1-, 3- and 5-year OS. To establish a full model all items collected underwent univariate pre-filtering. All available items were analyzed via a univariate model and items with a p-value of 0.2 or lower were analyzed in our multivariate model using SAS 9.4. Results: 220 patients were included for analysis, 183 (83%) were stage IV. 57% were males. Racial/ethnic distribution included 45% Non-Hispanic Whites (NHW), 32% Blacks, 13% Hispanic Whites (HW) and 10% Asians. 71% were tested for EGFR, ALK, or both. 21 patients (13.7%) were found to have EGFR mutations and 7 patients (4.9%) had ALK fusions. For EGFR, tissue (T) was tested in 134 and blood (B) in 44, both T and B in 23 with concordance in 20. For ALK, T was done in 129, B in 44, 23 had both, with concordance in 21. Testing was inconclusive in 3 (T) for EGFR and 5 (3 T and 2 B) for ALK. Lung was the most common site tested for EGFR with 90 patients followed by liver (8), lymph node (8), and bone (8). Females accounted for 67% of EGFR+ and 57% for ALK+. Asians accounted for 43% of EGFR+ and 28% of ALK+. Median OS in days for study population: 155, EGFR+: 845, ALK+: 1333, both-:162, NT: 105. At 3 years, EGFR+ (HR: 0.427; 95% CI: 0.222, 0.822; p-value: 0.0109) and ALK+ (HR: 0.191; 95% CI: 0.046, 0.795; p-value: 0.0229) showed a significant reduction in the hazard of death compared to both-. NT patients had 1.679 times higher hazard of death when compared to both- (HR: 1.679; 95% CI: 1.206, 2.338; p-value: 0.0021). Similar pattern was seen for EGFR+ for 1 and 5 year OS and for ALK+ at 5 year OS. Conclusions: Prevalence of EGFR and ALK alterations at JPS is similar to nationally reported statistics. Tissue testing is the gold standard for identifying these alterations. 29% of the patients were not tested. Median survival of EGFR+ or ALK+ patients is significantly longer than other cohorts. Citation Format: Vivek Athipatla, James Blackwell, Anna Diaz, Bassam Ghabach, Kalyani Narra. Patterns of testing and survival for EGFR mutation and ALK abnormalities in advanced lung cancer at John Peter Smith Hospital [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr B033.

A Review of Biomarkers and Their Clinical Impact in Resected Early-Stage Non-Small-Cell Lung Cancer.

The postoperative survival of early-stage non-small-cell lung cancer (NSCLC) patients remains unsatisfactory. In this review, we examined the relevant literature to ascertain the prognostic effect of related indicators on early-stage NSCLC. The prognostic effects of the epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), mesenchymal-epithelial transition (MET), C-ros oncogene 1 (ROS1), or tumour protein p53 (TP53) alterations in resected NSCLC remains debatable. Kirsten rat sarcoma viral oncogene homologue (KRAS) alterations indicate unfavourable outcomes in early-stage NSCLC. Meanwhile, adjuvant or neoadjuvant EGFR-targeted agents can substantially improve prognosis in early-stage NSCLC with EGFR alterations. Based on the summary of current studies, resected NSCLC patients with overexpression of programmed death-ligand 1 (PD-L1) had worsening survival. Conversely, PD-L1 or PD-1 inhibitors can substantially improve patient survival. Considering blood biomarkers, perioperative peripheral venous circulating tumour cells (CTCs) and pulmonary venous CTCs predicted unfavourable prognoses and led to distant metastases. Similarly, patients with detectable perioperative circulating tumour DNA (ctDNA) also had reduced survival. Moreover, patients with perioperatively elevated carcinoembryonic antigen (CEA) in the circulation predicted significantly worse survival outcomes. In the future, we will incorporate mutated genes, immune checkpoints, and blood-based biomarkers by applying artificial intelligence (AI) to construct prognostic models that predict patient survival accurately and guide individualised treatment.

Intratumoral thrombosis as a histological biomarker for predicting epidermal growth factor receptor alteration and poor prognosis in patients with glioblastomas.

Intratumoral thrombosis is a specific finding in glioblastomas and considered the origin of palisading necrosis. Its distribution and contribution to the glioblastoma pathophysiology and systemic thrombosis are obscure, although deep vein thrombosis is a common complication in glioblastoma cases. Clinicopathological and genetic analyses were performed on 97 glioblastoma tissue specimens to elucidate the role of thrombotic events and associated molecular abnormalities. Morphologically, intratumoral thrombosis was observed more frequently in vessels composed of single-layered CD34-positive endothelium and/or αSMA-positive pericytes in the tumor periphery, compared to microvascular proliferation with multi-channeled and pericyte-proliferating vessels in the tumor center. Intratumoral thrombosis was significantly correlated with the female sex, high preoperative D-dimer levels, and epidermal growth factor receptor (EGFR) amplification. The presence of one or more thrombi in 20 high-power fields was a predictive marker of EGFR amplification, with a sensitivity of 81.5% and specificity of 52.6%. RNA sequencing demonstrated that the group with many thrombi had higher EGFR gene expression levels than the group with few thrombi. The tumor cells invading along the vessels in the tumor periphery were positive for wild-type EGFR but negative for EGFRvIII, whereas the cells around the microvascular proliferation (MVP) in the tumor center were positive for both wild-type EGFR and EGFRvIII. Intratumoral thrombosis is an independent poor prognostic factor. Aberrant but exquisitely regulated EGFR can induce thrombosis in non-MVP vessels in the tumor invasion area and then promote palisading necrosis, followed by hypoxia, abnormal angiogenesis, and further tumor cell invasion.

EGFR alterations in glioblastoma play a role in antitumor immunity regulation.

The epidermal growth factor receptor (EGFR) is the most frequently altered gene in glioblastoma (GBM), which plays an important role in tumor development and anti-tumor immune response. While current molecular targeted therapies against the EGFR signaling pathway and its downstream key molecules have not demonstrated favorable clinical outcomes in GBM. Whereas tumor immunotherapies, especially immune checkpoint inhibitors, have shown durable antitumor responses in many cancers. However, the clinical efficacy is limited in patients carrying EGFR alterations, indicating that EGFR signaling may involve tumor immune response. Recent studies reveal that EGFR alterations not only promote GBM cell proliferation but also influence immune components in the tumor microenvironment (TME), leading to the recruitment of immunosuppressive cells (e.g., M2-like TAMs, MDSCs, and Tregs), and inhibition of T and NK cell activation. Moreover, EGFR alterations upregulate the expression of immunosuppressive molecules or cytokines (such as PD-L1, CD73, TGF-β). This review explores the role of EGFR alterations in establishing an immunosuppressive TME and hopes to provide a theoretical basis for combining targeted EGFR inhibitors with immunotherapy for GBM.

Ramucirumab plus erlotinib versus placebo plus erlotinib in previously untreated EGFR-mutated metastatic non-small-cell lung cancer (RELAY): exploratory analysis of next-generation sequencing results

Ramucirumab plus erlotinib (RAM+ ERL) demonstrated superior progression-free survival (PFS) over placebo+ ERL (PBO+ ERL) in the phase III RELAY study of patients with epidermal growth factor receptor (EGFR)-mutated metastatic non-small-cell lung cancer (EGFR+ mNSCLC; NCT02411448). Next-generation sequencing (NGS) was used to identify clinically relevant alterations in circulating tumor DNA (ctDNA) and explore their impact on treatment outcomes. Eligible patients with EGFR+ mNSCLC were randomized 1 : 1 to ERL (150 mg/day) plus RAM (10 mg/kg)/PBO every 2 weeks. Liquid biopsies were to be prospectively collected at baseline, cycle 4 (C4), and postdiscontinuation follow-up. EGFR and co-occurring/treatment-emergent (TE) genomic alterations in ctDNA were analyzed using Guardant360 NGS platform. In those with valid baseline samples, detectable activating EGFR alterations in ctDNA (aEGFR+) were associated with shorter PFS [aEGFR+: 12.7 months (n= 255) versus aEGFR-: 22.0 months (n= 131); hazard ratio (HR)= 1.87, 95% confidence interval (CI) 1.42-2.51]. Irrespective of detectable/undetectable baseline aEGFR, RAM+ ERL was associated with longer PFS versus PBO+ ERL [aEGFR+: median PFS (mPFS)= 15.2 versus 11.1 months, HR= 0.63, 95% CI 0.46-0.85; aEGFR-: mPFS= 22.1 versus 19.2 months, HR= 0.80, 95% CI 0.49-1.30]. Baseline alterations co-occurring with aEGFR were identified in 69 genes, most commonly TP53 (43%), EGFR (other than aEGFR; 25%), and PIK3CA (10%). PFS was longer in RAM+ ERL, irrespective of baseline co-occurring alterations. Clearance of baseline aEGFR by C4 was associated with longer PFS (mPFS= 14.1 versus 7.0 months, HR= 0.481, 95% CI 0.33-0.71). RAM+ ERL improved PFS outcomes, irrespective of aEGFR mutation clearance. TE gene alterations were most commonly in EGFR [T790M (29%), other (19%)] and TP53 (16%). Baseline aEGFR alterations in ctDNA were associated with shorter mPFS. RAM+ ERL was associated with improved PFS outcomes, irrespective of detectable/undetectable aEGFR, co-occurring baseline alterations, or aEGFR+ clearance by C4. aEGFR+ clearance by C4 was associated with improved PFS outcomes. Monitoring co-occurring alterations and aEGFR+ clearance may provide insights into mechanisms of EGFR tyrosine kinase inhibitor resistance and the patients who may benefit from intensified treatment schedules.

A phase 1 study to assess BDTX-1535, an oral EGFR inhibitor, in patients with glioblastoma or non–small-cell lung cancer.

TPS9156 Background: The epidermal growth factor receptor (EGFR) is a potent oncogene commonly altered in many cancers, including glioblastoma (GBM) and non-small cell lung cancer (NSCLC). EGFR tyrosine kinase activity driven by common EGFR mutations can be inhibited by small molecules, however, resistance to available agents may be driven by mutations in the EGFR active kinase site or other regions. BDTX-1535 is an orally available, highly potent, selective, irreversible inhibitor of EGFR mutations, including extracellular variants and amplifications commonly expressed in GBM and inhibits the common and uncommon EGFR mutations found in NSCLC, including the C797S mutation acquired following 3rd generation EGFR inhibitor therapy. Preclinical data demonstrated the ability of BDTX-1535 to cross the blood-brain barrier and produce sustained inhibition of EGFR signaling. Preclinical studies suggest that BDTX-1535 has the potential to be clinically active in suppressing tumor growth in patients with GBM and NSCLC with or without CNS metastases, including a potential survival benefit. Methods: BDTX-1535-101 (NCT05256290) is Phase 1, open-label, multicenter study to assess the safety, tolerability, PK, CNS activity, and preliminary antitumor activity of BDTX-1535 in recurrent GBM (rGBM) or locally advanced or metastatic NSCLC with or without CNS disease. The Monotherapy Dose Escalation portion will evaluate BDTX-1535 in patients with either rGBM expressing EGFR alterations or locally advanced/metastatic NSCLC harboring sensitizing EGFR mutations with or without CNS disease. Patients with rGBM must have previously received available standard therapy of surgical resection followed by chemoradiotherapy and/or temozolomide (TMZ). Eligible NSCLC patients must have EGFR mutated NSCLC that has progressed following standard of care EGFR inhibitor therapy. Once a provisional recommended Phase 2 dose (RP2D) has been established, BDTX-1535 monotherapy will be explored in the following Dose Expansion cohorts to further evaluate safety, PK, and preliminary assessment of efficacy: 1) rGBM with confirmed EGFR alterations, 2) NSCLC with uncommon EGFR mutations following EGFR inhibitor therapy; 3) NSCLC with acquired EGFR resistance mutation following a 3rd generation EGFR inhibitor in 1L setting. NSCLC patients may enroll with or without CNS metastases and must not be known to express excluded resistance mutations such as EGFR T790M or MET. BDTX-1535 will also be studied in combination with TMZ to assess safety, tolerability, and a recommended combination dose for the treatment of patients with rGBM harboring EGFR mutations or variants. Enrollment was initiated in 2022 and dose escalation is ongoing. Dose Expansion cohorts are expected to open in 2023. For additional information, please contact BDTX_1535_101_Study@bdtx.com . Clinical trial information: NCT05256290 .

A phase 1, open-label, first-in-human study of TAS2940 in patients with advanced solid tumors.

TPS3165 Background: Aberrant expression and signaling of the ERBB family of receptor tyrosine kinases, including epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2), has a role in the pathogenesis of solid tumors such as breast cancer (BC), non–small cell lung cancer (NSCLC), and glioblastoma (GBM). Although therapies that target HER2 are effective in early and advanced HER2-overexpressing BC, many patients develop resistance despite tumor dependence on HER2 at the time of progression. Approximately 4% of patients with NSCLC have HER2 mutations, mostly presenting as exon 20 insertions (ex20ins); however, approved HER2/EGFR tyrosine kinase inhibitors (TKIs) have limited efficacy in patients with NSCLC and HER2 ex20ins. Many patients with NSCLC or BC develop brain metastases, and EGFR alterations, including EGFRvIII mutations, are common in GBM. There is therefore a need for a brain-penetrable TKI with activity against tumors harboring HER2/EGFR alterations. TAS2940 is a potent, selective, and orally bioavailable pan-ERBB inhibitor that has shown promising preclinical efficacy against cancers with a variety of HER2/EGFR mutations and amplifications. Further, TAS2940 inhibited tumor growth and induced tumor regression in a dose-dependent manner in nude mice intracranially implanted with NCI-N87, a HER2-overexpressing human gastric cancer cell line. Methods: TAS2940-101 (NCT04982926) is an open-label, phase 1, first-in-human trial to evaluate the safety, tolerability, pharmacokinetics (PK), and preliminary antitumor activity of TAS2940 in patients with advanced solid tumors and HER2/ EGFR aberrations. Eligible patients are aged ≥18 years, have non-measurable (Part 1) or measurable (Part 1 and 2) disease per RECIST 1.1 or RANO criteria, ECOG performance status 0/1, and adequate organ function. Patients with non-stable brain metastases are excluded. Part 1 (dose escalation) will use a Bayesian optimal interval design with a starting dose of 15 mg/kg orally QD (planned dose levels: 15, 30, 60, 120, 240 and 480 mg). Once the recommended phase 2 dose is determined, Part 2 (dose expansion) will enroll patients with NSCLC (Cohort A), HER2+ BC (Cohort B), recurrent/refractory GBM (Cohort C), or other solid tumors with EGFR/ HER2 aberrations (Cohort D). The primary objectives are the maximum tolerated dose of TAS2940 in Part 1 and antitumor activity in Part 2. Secondary objectives include antitumor activity in Part 1. The safety and PK profile of TAS2940 will be assessed in both parts. Approximately 142 patients will be enrolled, comprising ~42 in Part 1 and ~100 in Part 2. As of January 24, 2023, 15 patients have been enrolled. No dose-limiting toxicities have been reported with dose escalation up to 240 mg QD. Recruitment is ongoing. Clinical trial information: NCT04982926 .

NTRK Gene Fusions in Non-Small-Cell Lung Cancer: Real-World Screening Data of 1068 Unselected Patients.

(1) Background: The main objectives of our study are (i) to determine the prevalence of NTRK (neurotrophic tyrosine kinase) fusions in a routine diagnostic setting in NSCLC (non-small cell lung cancer) and (ii) to investigate the feasibility of screening approaches including immunohistochemistry (IHC) as a first-line test accompanied by fluorescence in situ hybridization (FISH) and RNA-(ribonucleic acid-)based next-generation sequencing (RNA-NGS). (2) Methods: A total of 1068 unselected consecutive patients with NSCLC were screened in two scenarios, either with initial IHC followed by RNA-NGS (n = 973) or direct FISH testing (n = 95). (3) Results: One hundred and thirty-three patients (14.8%) were IHC positive; consecutive RNA-NGS testing revealed two patients (0.2%) with NTRK fusions (NTRK1-EPS15 (epidermal growth factor receptor pathway substrate 15) and NTRK1-SQSTM1 (sequestosome 1)). Positive RNA-NGS was confirmed by FISH, and NTRK-positive patients benefited from targeted treatment. All patients with direct FISH testing were negative. RNA-NGS- or FISH-positive results were mutually exclusive with alterations in EGFR (epidermal growth factor receptor), ALK (anaplastic lymphoma kinase), ROS1 (ROS proto-oncogene 1), BRAF (proto-oncogene B-Raf), RET (rearranged during transfection) or KRAS (kirsten rat sarcoma viral oncogene). Excluding patients with one of these alterations raised the prevalence of NTRK-fusion positivity among panTrk-(tropomyosin receptor kinase-) IHC positive samples to 30.5%. (4) Conclusions: NTRK fusion-positive lung cancers are exceedingly rare and account for less than 1% of patients in unselected all-comer populations. Both RNA-NGS and FISH are suitable to determine clinically relevant NTRK fusions in a real-world setting. We suggest including panTrk-IHC in a diagnostic workflow followed by RNA-NGS. Excluding patients with concurrent molecular alterations to EGFR/ALK/ROS1/BRAF/RET or KRAS might narrow the target population.

Abstract CT127: A phase 1 study to assess BDTX-1535, an oral EGFR inhibitor, in patients with glioblastoma or non-small cell lung cancer

Abstract Background: The epidermal growth factor receptor (EGFR) is a potent oncogene commonly altered in many cancers, including glioblastoma (GBM) and non-small cell lung cancer (NSCLC). EGFR tyrosine kinase activity driven by common EGFR mutations can be inhibited by small molecules, however, resistance to available agents may be driven by mutations in the EGFR active kinase site or other regions. BDTX-1535 is an orally available, highly potent, selective, irreversible inhibitor of EGFR mutations, including extracellular variants and amplifications commonly expressed in GBM and inhibits the uncommon EGFR mutations found in NSCLC, including the C797S mutation acquired following 3rd generation EGFR inhibitor therapy. Preclinical data demonstrated the ability of BDTX-1535 to cross the blood-brain barrier and produce sustained inhibition of EGFR signaling. Preclinical studies suggest that BDTX-1535 has potential to be clinically active in suppressing tumor growth in patients with GBM and NSCLC with or without CNS metastases, including a potential survival benefit. Methods: BDTX-1535-101 (NCT05256290) is Phase 1, open-label, multicenter study to assess the safety, tolerability, PK, CNS penetrance, and preliminary antitumor activity of BDTX-1535 in recurrent GBM (rGBM) or locally advanced or metastatic NSCLC with or without CNS disease. The Monotherapy Dose Escalation portion will evaluate BDTX-1535 in patients with either rGBM expressing EGFR alterations or locally advanced/metastatic NSCLC harboring sensitizing EGFR mutations with or without CNS disease. Patients with rGBM must have previously received available standard therapy of surgical resection followed by chemoradiotherapy and/or temozolomide (TMZ). Eligible NSCLC patients must have EGFR mutated NSCLC that has progressed following standard of care EGFR inhibitor therapy. Once a provisional recommended Phase 2 dose (RP2D) has been established, BDTX-1535 monotherapy will be explored in the following Dose Expansion cohorts to further evaluate safety, PK, and preliminary assessment of efficacy: 1) rGBM with confirmed EGFR alterations, 2) NSCLC with uncommon EGFR mutations following EGFR inhibitor therapy; 3) NSCLC with acquired EGFR resistance mutation following a 3rd generation EGFR inhibitor in 1L setting. NSCLC patients may enroll with or without CNS metastases and must not be known to express excluded resistance mutations such as EGFR T790M or MET. BDTX-1535 will also be studied in combination with TMZ to assess safety, tolerability, and a recommended combination dose for the treatment of patients with rGBM harboring EGFR mutations or variants. Enrollment was initiated in 2022 and dose escalation is ongoing. Dose Expansion cohorts are expected to open in 2023. For additional information, please contact BDTX_1535_101_Study@bdtx.com Citation Format: Melissa Johnson, Jason Henry, Alex Spira, James Battiste, Iyad Alnahhas, Manmeet Ahluwalia, Minal Barve, Jeffrey Edenfield, DoHyun Nam, Sudharshan Eathiraj, Julio Hajdenberg, Sergey Yurasov, Helena Yu, Patrick Wen. A phase 1 study to assess BDTX-1535, an oral EGFR inhibitor, in patients with glioblastoma or non-small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr CT127.

HER2 expression defines unique requirements for flotillin and c-Src in EGFR signaling.

The epidermal growth factor receptor (EGFR) controls many cellular functions. Upon binding its ligand, the receptor undergoes dimerization, phosphorylation and activation of signals including the phosphoinositide-3-kinase (PI3K)-Akt pathway. Although some studies have indicated that EGFR signaling may be controlled by signal enrichment within various membrane rafts, such as flotillin nanodomains, others have found a limited effect of disruption of these nanodomains on EGFR signaling, suggesting that specific factors may define context-specific control of EGFR signaling. Ligand-bound EGFR can homodimerize or instead undergo heterodimerization with the related receptor HER2 (also known as ERBB2) when the latter is expressed. We examined how EGFR signaling in the presence of HER2 distinctly requires flotillin nanodomains. Induction of HER2 expression altered EGFR signaling duration, which is consistent with EGFR-HER2 heterodimer formation. EGFR and c-Src (also known as SRC) localized within plasma membrane structures demarked by flotillin-1 more prominently in HER2-expressing cells. Consistently, HER2-expressing cells, but not cells lacking HER2, were dependent on flotillin-1 and c-Src for EGFR signaling leading to Akt activation and cell proliferation. Hence, HER2 expression establishes a requirement for flotillin membrane rafts and c-Src in EGFR signaling.

Immunohistochemical based molecular subtypes of muscle-invasive bladder cancer: association with HER2 and EGFR alterations, neoadjuvant chemotherapy response and survival

Muscle-invasive bladder cancers (MIBCs) is a group of molecularly heterogonous diseases that could be stratified into subtypes with distinct clinical courses and sensitivities to chemotherapy. Clinical application of molecular subtypes could help in prediction of neoadjuvant chemotherapy (NAC) responders. Immunohistochemical (IHC) markers such as GATA3, cytokeratin (CK) 5/6, and p53 are associated with these subtypes and are widely available. Human epidermal growth factor receptor 2 (HER2) and epidermal growth factor receptor (EGFR) are mutated in multiple cancers including MIBC and are potential therapeutic targets. HER2/EGFR status of MIBC subtypes has not been investigated. Tissue microarrays (TMAs) were constructed from transurethral resection of the bladder tumor (TURB) specimens and stained with GATA3,CK5/6,p53 and HER2 in addition to Quantitative Reverse Transcription PCR for detection of EGFR gene. Of the total cases, 45% were luminal, 36.7% basal and 18.3% p53 wild subtype (p53-WT). Univariate analysis showed that overall survival (OS) and disease-free progression survival (DFS) were significantly longer for luminal subtype. In multivariate analysis, molecular subtype, HER2 status and LV invasion were independent prognostic factors for DFS and OS. Basal subtype showed a significantly better response to NAC. HER2 expression was significantly higher in luminal while EGFR expression was significantly higher in basal subtype. Kaplan-Meier survival curves revealed a significant longer OS and DFS for HER2 negative than positive cases. MIBC can be stratified using a simple IHC panel [GATA3,CK5/6,P53] into clinically relevant prognostic molecular subtypes. Basal tumors are aggressive and respond well to NAC while luminal have better OS. P53-WT tumors are chemoresistant and require further treatments. HER2 and EGFR are potential therapeutic targets for molecular subtypes of MIBC where luminal tumors are more likely to benefit from HER2 and basal from EGFR directed therapies.

Ethnomedicine claim directed in-silico prediction of epidermal growth factor receptor kinase antagonist: an untapped reservoir of prospective anticancer agents

The epidermal growth factor receptor (EGFR) is a tyrosine kinase (TK) that belongs to the ErbB family and governs important cellular functions like reproduction, survival, motility, and differentiation. Overexpression, intensification, and alteration of EGFR occur in a wide range of human malignancies and are associated with tumor progression and decreased anticancer drug sensitivity. As a result, EGFR has been identified as one of the primary anticancer targets. As cancer is more likely to be poorly understood in traditional medical practices, the extrapolation of an ethnomedicine-led strategy to identifying and prioritizing anticancer medicinal plants has been questioned. Nonetheless, given the challenges of developing innovative anticancer drugs that are effective, safe, inexpensive, and widely available, ethnomedicinal studies play critical roles in identifying relevant medicinal plants that can be further investigated. This study employed pharmacophore modeling, molecular docking, and molecular dynamics simulation to develop an effective agent as an inhibitor for EGFR. The final findings revealed that the selected bioactive compound stabilized the EGFR protein. The optimum orientations of the various inhibitors was Friedelin and it was chosen and subjected, along with the FDA-approved drug, to molecular dynamics modeling to determine the molecular interaction of the medication with various mutational sites in order to deduce the suitable orientation for the inhibitors. The study also attest to the ethnomedicinal claims that ethnomedicinal plants played a huge role in anticancer drug discovery and that their exploration can change the bleak picture cancer paints in our societies today.

Macrocyclization of Quinazoline-Based EGFR Inhibitors Leads to Exclusive Mutant Selectivity for EGFR L858R and Del19.

Activating mutations in the epidermal growth factor receptor (EGFR) are frequent oncogenic drivers of non-small-cell lung cancer (NSCLC). The most frequent alterations in EGFR are short in-frame deletions in exon 19 (Del19) and the missense mutation L858R, which both lead to increased activity and sensitization of NSCLC to EGFR inhibition. The first approved EGFR inhibitors used for first-line treatment of NSCLC, gefitinib and erlotinib, are quinazoline-based. However, both inhibitors have several known off-targets, and they also potently inhibit wild-type (WT) EGFR, resulting in side effects. Here, we applied a macrocyclic strategy on a quinazoline-based scaffold as a proof-of-concept study with the goal of increasing kinome-wide selectivity of this privileged inhibitor scaffold. Kinome-wide screens and SAR studies yielded 3f, a potent inhibitor for the most common EGFR mutation (EGFR Del19: 119 nM) with selectivity against the WT receptor (EGFR: >10 μM) and the kinome.

STEM-22. EFFECT OF A SRC INHIBITORY PEPTIDE BASED ON CONNEXIN43 ON NEURAL STEM CELLS WITH GLIOMA-DRIVER MUTATIONS

Abstract Glioblastomas are one of the most malignant tumors. Glioma Stem Cells (GSCs) are a subpopulation of cells resistant to standard treatments, responsible for tumor recurrence. Strong evidence supports that Neural Stem Cells (NSCs) from the subventricular zone (SVZ) are the origin of GSCs. This transition frequently concurs with epidermal growth factor receptor (EGFR) overexpression or mutations, such as EGFRvIII. Our group designed a cell penetrating peptide based on connexin43 (TAT-Cx43266-283) that inhibits the oncoprotein c-Src and therefore targets GSCs, increasing survival in glioma-bearing mice. Because c-Src and EGFR signaling are closely related, we explored the effect of TAT-Cx43266-283 in the transition of NSCs to GSCs. We compared the effect of TAT-Cx43266-283, control peptides, temozolomide and erlotinib, a common EGFR inhibitor, in SVZ NSCs (Control-NSCs) and murine NSC and patient-derived GSCs with key glioma-driver mutations in Nf1, PTEN and EGFR. EGFR signaling pathway was analyzed by Western blot. Furthermore, we are analyzing the effect of TAT-Cx43266-283 in a mouse model where tumors originate from SVZ NSCs with glioma-driver mutations. Our results showed a strong effect of TAT-Cx43266-283 in cell viability of NSCs and patient-derived GSCs with EGFR amplification or active EGFRvIII, without significant effects in Control-NSCs. Importantly, we found a lower effect of temozolomide, erlotinib, and other control peptides in these cells. Western blot analyses suggest that TAT-Cx43266-283 decreases EGFR, EGFRvIII and c-Src activity. Preliminary in vivo results suggest that TAT-Cx43266-283 decreases tumor size and enhances survival in mice bearing gliomas initiated by altered NSCs. So far, our results show that TAT-Cx43266-283 impairs EGFR signaling pathway with the subsequent reduction in the proliferation and survival of NSCs or GSCs with EGFR alterations. These results stress the relevance of TAT-Cx43266-283 as a future therapy against glioblastoma, alone or in combination with other treatments.