Osimertinib for pretreated EGFR Thr790Met-positive advanced non-small-cell lung cancer (AURA2): a multicentre, open-label, single-arm, phase 2 study

Benefit from Almonertinib after Osimertinib treat EGFR 19 exon deletion NSCLC induced Severe rash: a case report

Osimertinib, a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), has been recommended as a first-line treatment of EGFR-positive non-small cell lung cancer (NSCLC). Skin rash is one of the most common side effects of osimertinib, and can have an impact on patients' quality of life and follow-up. However, there are few reports on the safety and efficacy of switching therapy with osimertinib and the other three generations of TKIs. In this paper, we present a case of NSCLC with an EGFR exon 19 deletion (19del) and MET gene amplification who developed a severe rash after 2 months of treatment with osimertinib that did not recur after switching to replacement therapy with aumonertinib. Our findings indicate that aumonertinib is as effective as osimertinib in treating EGFR19del, while also exhibiting a lower occurrence of adverse skin reactions. This may result in an improved quality of life for patients.

Prediction of epidermal growth factor receptor mutation subtypes in non-small cell lung cancer from hematoxylin and eosin-stained slides using deep learning

Accurate assessment of epidermal growth factor receptor (EGFR) mutation status and subtype are critical for the treatment of non-small cell lung cancer (NSCLC) patients. Conventional molecular testing methods for detecting EGFR mutations have limitations. In this study, an artificial intelligence-powered deep learning framework was developed for weakly supervised prediction of EGFR mutations in NSCLC from hematoxylin and eosin (H&E)-stained histopathology whole-slide images (WSIs). The study cohort was partitioned into training and validation subsets. Foreground regions containing tumor tissue were extracted from WSIs. A convolutional neural network (CNN) employing a contrastive learning paradigm was implemented to extract patch-level morphological features. These features were aggregated using a vision-transformer-based model to predict EGFR mutation status and classify patient cases. The established prediction model was validated on unseen datasets. In internal validation with a cohort from (USTC)(n=172), the model achieved patient-level areas under the receiver operating characteristic (ROC) curve (AUCs) of 0.927 and 0.907, sensitivities of 81.6% and 93.0%, and specificities of 83.3% and 92.3%, for surgical resection and biopsy specimens in EGFR mutation subtype prediction, respectively. External validation with cohorts from the Second Affiliated Hospital of Anhui Medical University (AMU) and the First Affiliated Hospital of Wannan Medical College (WMC) (n=193) yielded patient-level AUCs of 0.849 and 0.871, sensitivities of 75.7% and 72.1%, and specificities of 90.5% and 90.3% for surgical and biopsy specimens, respectively. Further validation with The Cancer Genome Atlas (TCGA) dataset (n=81) showed an AUC of 0.861, sensitivity of 84.6%, and specificity of 90.5%. Deep learning solutions demonstrate potential advantages for automated, non-invasive, fast, cost-effective, and accurate inference of EGFR alterations from histomorphology. Integration of such artificial intelligence frameworks into routine digital pathology workflows could augment existing molecular testing pipelines.

Phase II Efficacy and Safety of 80 mg Osimertinib in Patients With Leptomeningeal Metastases Associated With Epidermal Growth Factor Receptor Mutation-Positive Non-Small Cell Lung Cancer (BLOSSOM)

PURPOSE

Leptomeningeal metastases (LMs) exhibit a high incidence in patients with epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC) post-treatment with first- or second-generation EGFR tyrosine kinase inhibitors (TKIs). This investigation evaluates the efficacy, safety, and pharmacokinetics of 80 mg once daily osimertinib in patients with LMs resistant to prior first- or second-generation EGFR TKIs.

MATERIALS AND METHODS

In this phase II multicenter, open-label, single-arm study, 80 mg osimertinib was administered to patients with EGFR-mutated NSCLC who had developed LMs subsequent to treatment with prior EGFR TKIs. The primary end point was overall survival (OS), assessed alongside objective response rate by the blinded independent central review (BICR) and a pharmacokinetic analysis of plasma and cerebrospinal fluid (CSF) on the first day of cycles 3 and 6.

RESULTS

A total of 73 patients diagnosed with LM were treated with osimertinib, including 64 patients evaluable for the LM efficacy set-T790M negative (n = 62) and T790M positive (n = 2). The median OS in the full-analysis set was 15.6 months (95% CI, 11.5 to 20.2). The objective response rate for LM was 51.6%, including a 15.6% complete response, and the disease control rate was 81.3% by BICR in the LM efficacy evaluable set. The median LM progression-free survival by BICR was 11.2 months (95% CI, 7.7 to 15.3), the duration of response was 12.6 months (95% CI, 7.6 to 17.7), and OS was 15.0 months (95% CI, 11.3 to 18.7). Pharmacokinetic analysis showed that the CSF to free plasma osimertinib ratio was 22%. Most safety profiles were grade 1 and 2.

CONCLUSION

The study demonstrates significant intracranial efficacy and survival benefits of 80 mg once daily osimertinib in NSCLC patients with LMs. The data support considering daily 80 mg of osimertinib as a treatment option for EGFR-mutated NSCLC patients with LMs, irrespective of T790M mutation status.

QT-Interval Prolongation, Torsades de Pointes, and Heart Failure With EGFR Tyrosine Kinase Inhibitors in Non-Small Cell Lung Cancer: Systematic Review

A systematic literature review was conducted to determine the incidence and mortality of QT-interval prolongation (QTp), torsades de pointes (TdP), and heart failure (HF) in patients with non-small cell lung cancer (NSCLC) who received epidermal growth factor receptor (EGFR) TKIs. Of 296 identified publications, 95 met eligibility criteria and were abstracted for QTp/TdP and HF outcomes (QTp/TdP: 83 publications, including 5 case study publications; HF: 79 publications, including 6 case study publications [involving 8 patients]). QTp incidence ranged from 0% to 27.8% in observational studies and from 0% to 11% in clinical trials, with no deaths due to QTp. There were no TdP events or deaths due to TdP. The incidence of HF ranged from 0% to 8%, and HF mortality rates ranged from 0% to 4%. Patients receiving treatment with EGFR TKIs should be monitored for signs of QTp, TdP, and HF per prescribing information. Standardized definitions and methods to improve monitoring of QTp, TdP, and HF-related events are needed in patients with NSCLC.

Primary versus acquired epidermal growth factor receptor Thr790Met mutant non-small cell lung cancer: clinical features and prognoses

PURPOSE

This study aimed to identify the impact of epidermal growth factor receptor (EGFR) T790M mutations on clinical characteristics and prognosis.

METHODS

Retrospective analyses were conducted on the differences on clinicopathological features and prognosis between primary and acquired T790M mutations. Subgroup analyses were performed for primary T790M coexisting with other mutations.

RESULTS

Patients with primary T790M mutations showed a 60.53% (23/38) incidence of concurrent L858R mutations, 18.42% (7/38) for 19del mutations and a 21.05% (8/38) occurrence of brain metastases. Conversely, those with acquired T790M mutations demonstrated respective frequencies of 36.53% (61/167), 58.68% (98/167) and 44.31% (74/167), with all comparisons yielding p < 0.05. The median overall survival differed significantly between the two groups, with a duration of 33 months for patients with primary T790M mutations as compared to 48 months for those with acquired mutations (p = 0.030). Notably, among patients with L858R co-mutations, when treated with third-generation EGFR-TKIs, those with acquired T790M mutations experienced a significantly prolonged median time to treatment failure compared to those with primary mutations (17 months vs. 9 months, p = 0.009).

CONCLUSION

Patients with primary T790M have unique molecular features and had worse prognosis compared with acquired T790M. Resistance to third-generation EGFR-TKIs seems to be associated with the presence of EGFR co-mutations.

Real-world osimertinib pretreatment experience in patients with epidermal growth factor receptor T790M mutation-positive locally advanced or metastatic non-small cell lung cancer

Osimertinib has demonstrated efficacy in patients with epidermal growth factor receptor (EGFR) T790M-positive non-small cell lung cancer (NSCLC) in clinical trials. However, real-world data on its effectiveness remain scarce. Taiwanese patients with T790M-positive locally advanced or metastatic NSCLC and progressive disease following treatment with at least one EGFR tyrosine kinase inhibitor (TKI) were enrolled from the osimertinib early access program. Of the 419 patients (mean age, 63 years; female, 67%), 53% were heavily pretreated (≥ third-line [3L]), making osimertinib a fourth-line (4L) intervention. The median progression-free survival (PFS) was 10.5 months (95% confidence interval [CI]: 8.95-11.41); the 18-month PFS rate was 26.5%. The median overall survival (OS) was 19.0 months (95% CI: 16.30-20.95); the 24-month OS rate was 40.9%. The objective response rate was 32.46%, and the disease control rate was 86.38%. The median time to treatment discontinuation of osimertinib monotherapy was 11.9 months (95% CI: 10.49-13.11). Subgroup analyses of median PFS and OS in the chemotherapy combination group vs. the osimertinib monotherapy group yielded no difference. Central nervous system (CNS) metastasis, number of prior lines of therapy, and types of initial EGFR-TKIs did not significantly impact outcomes. The median PFS values were 9.0 (95% CI: 5.18-11.34) and 10.9 (95% CI: 9.18-11.90) months with and without CNS metastasis, respectively, and 10.8 (95% CI: 8.59-12.69), 13.6 (95% CI: 10.89-16.3), and 9.2 (95% CI: 7.8-10.62) months for second-line (2L), 3L, and ≥4L therapy, respectively. In patients who received osimertinib as 2L therapy, the median PFS values in response to prior afatinib, erlotinib and gefitinib treatment were 11.2 (95% CI: 4.85-4.79), 10.5 (95% CI: 8.59-20.26) and 8.7 (95% CI: 7.21-16.79) months, respectively. Overall, real-world data from Taiwan support the clinical benefits of osimertinib in EGFR T790M -positive NSCLC.

Site-specific mutagenesis screening in KRASG12D mutant library to uncover resistance mechanisms to KRASG12D inhibitors

KRAS plays a crucial role in regulating cell survival and proliferation and is one of the most commonly mutated oncogenes in human cancers. The novel KRASG12D inhibitor, MRTX1133, demonstrates promising antitumor efficacy in vitro and in vivo. However, the development of acquired resistance in treated patients presents a considerable challenge to sustained therapeutic effectiveness. In response to this challenge, we conducted site-specific mutagenesis screening to identify potential secondary mutations that could induce resistance to MRTX1133. We screened a range of KRASG12D variants harboring potential secondary mutations, and 44 representative variants were selected for in-depth validation of the pooled screening outcomes. We identified eight variants (G12D with V9E, V9W, V9Q, G13P, T58Y, R68G, Y96W, and Q99L) that exhibited substantial resistance, with V9W showing notable resistance, and downstream signaling analyses and structural modeling were conducted. We observed that secondary mutations in KRASG12D can lead to acquired resistance to MRTX1133 and BI-2865, a novel pan-KRAS inhibitor, in human cancer cell lines. This evidence is critical for devising new strategies to counteract resistance mechanisms and, ultimately, enhance treatment outcomes in patients with KRASG12D-mutant cancers.

Discovery of a Novel Potent EGFR Inhibitor Against EGFR Activating Mutations and On-Target Resistance in NSCLC

PURPOSE

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) serve as the standard first-line therapy for EGFR-mutated non-small cell lung cancer (NSCLC). Despite the sustained clinical benefits achieved through optimal EGFR-TKI treatments, including the third-generation EGFR-TKI osimertinib, resistance inevitably develops. Currently, there are no targeted therapeutic options available postprogression on osimertinib. Here, we assessed the preclinical efficacy of BI-4732, a novel fourth-generation EGFR-TKI, using patient-derived preclinical models reflecting various clinical scenarios.

EXPERIMENTAL DESIGN

The antitumor activity of BI-4732 was evaluated using Ba/F3 cells and patient-derived cell/organoid/xenograft models with diverse EGFR mutations. Intracranial antitumor activity of BI-4732 was evaluated in a brain-metastasis mouse model.

RESULTS

We demonstrated the remarkable antitumor efficacy of BI-4732 as a single agent in various patient-derived models with EGFR_C797S-mediated osimertinib resistance. Moreover, BI-4732 exhibited activity comparable to osimertinib in inhibiting EGFR-activating (E19del and L858R) and T790M mutations. In a combination treatment strategy with osimertinib, BI-4732 exhibited a synergistic effect at significantly lower concentrations than those used in monotherapy. Importantly, BI-4732 displayed potent antitumor activity in an intracranial model, with low efflux at the blood-brain barrier.

CONCLUSIONS

Our findings highlight the potential of BI-4732, a selective EGFR-TKI with high blood-brain barrier penetration, targeting a broad range of EGFR mutations, including C797S, warranting clinical development.

Therapy for Stage IV Non-Small Cell Lung Cancer With Driver Alterations: ASCO Living Guideline, Version 2023.3

PURPOSE

To provide evidence-based recommendations for patients with stage IV non-small cell lung cancer with driver alterations.

METHODS

This ASCO living guideline offers continually updated recommendations based on an ongoing systematic review of randomized clinical trials (RCTs), with the latest time frame spanning February to October 2023. An Expert Panel of medical oncology, pulmonary, community oncology, research methodology, and advocacy experts were convened. The literature search included systematic reviews, meta-analyses, and randomized controlled trials. Outcomes of interest include efficacy and safety. Expert Panel members used available evidence and informal consensus to develop evidence-based guideline recommendations.

RESULTS

This guideline consolidates all previous updates and reflects the body of evidence informing this guideline topic. Eight new RCTs were identified in the latest search of the literature to date.

RECOMMENDATIONS

Evidence-based recommendations were updated to address first, second, and subsequent treatment options for patients based on targetable driver alterations.Additional information is available at www.asco.org/living-guidelines.

Liquid biopsy techniques and lung cancer: diagnosis, monitoring and evaluation

Lung cancer stands as the most prevalent form of cancer globally, posing a significant threat to human well-being. Due to the lack of effective and accurate early diagnostic methods, many patients are diagnosed with advanced lung cancer. Although surgical resection is still a potential means of eradicating lung cancer, patients with advanced lung cancer usually miss the best chance for surgical treatment, and even after surgical resection patients may still experience tumor recurrence. Additionally, chemotherapy, the mainstay of treatment for patients with advanced lung cancer, has the potential to be chemo-resistant, resulting in poor clinical outcomes. The emergence of liquid biopsies has garnered considerable attention owing to their noninvasive nature and the ability for continuous sampling. Technological advancements have propelled circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), extracellular vesicles (EVs), tumor metabolites, tumor-educated platelets (TEPs), and tumor-associated antigens (TAA) to the forefront as key liquid biopsy biomarkers, demonstrating intriguing and encouraging results for early diagnosis and prognostic evaluation of lung cancer. This review provides an overview of molecular biomarkers and assays utilized in liquid biopsies for lung cancer, encompassing CTCs, ctDNA, non-coding RNA (ncRNA), EVs, tumor metabolites, TAAs and TEPs. Furthermore, we expound on the practical applications of liquid biopsies, including early diagnosis, treatment response monitoring, prognostic evaluation, and recurrence monitoring in the context of lung cancer.

Molecular mechanisms underlying the regulation of tumour suppressor genes in lung cancer

Tumour suppressor genes play a cardinal role in the development of a large array of human cancers, including lung cancer, which is one of the most frequently diagnosed cancers worldwide. Therefore, extensive studies have been committed to deciphering the underlying mechanisms of alterations of tumour suppressor genes in governing tumourigenesis, as well as resistance to cancer therapies. In spite of the encouraging clinical outcomes demonstrated by lung cancer patients on initial treatment, the subsequent unresponsiveness to first-line treatments manifested by virtually all the patients is inherently a contentious issue. In light of the aforementioned concerns, this review compiles the current knowledge on the molecular mechanisms of some of the tumour suppressor genes implicated in lung cancer that are either frequently mutated and/or are located on the chromosomal arms having high LOH rates (1p, 3p, 9p, 10q, 13q, and 17p). Our study identifies specific genomic loci prone to LOH, revealing a recurrent pattern in lung cancer cases. These loci, including 3p14.2 (FHIT), 9p21.3 (p16INK4a), 10q23 (PTEN), 17p13 (TP53), exhibit a higher susceptibility to LOH due to environmental factors such as exposure to DNA-damaging agents (carcinogens in cigarette smoke) and genetic factors such as chromosomal instability, genetic mutations, DNA replication errors, and genetic predisposition. Furthermore, this review summarizes the current treatment landscape and advancements for lung cancers, including the challenges and endeavours to overcome it. This review envisages inspired researchers to embark on a journey of discovery to add to the list of what was known in hopes of prompting the development of effective therapeutic strategies for lung cancer.

Early dose reduction of osimertinib in advanced EGFR-mutated non-small cell lung cancer

Osimertinib has become the standard of care for epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC). In order to prevent or treat toxicity, the osimertinib dose may be reduced. However, data regarding the impact of dose reduction during treatment are limited. We aimed to compare the efficacy of osimertinib early dose reduction during the first 3 months of treatment with late dose reduction in EGFR-mutated advanced NSCLC. This retrospective study included patients with EGFR-mutated advanced NSCLC who received osimertinib. We constituted two groups: 'early dose reduction' (early) with patients receiving a reduced dose of osimertinib from 80 to 40 mg within the 3 months of osimertinib initiation and 'late dose reduction' (late) with patients receiving a reduced dose after 3 months of full-dose treatment. Thirty-five patients were included, with 17 and 18 patients in the early and late groups, respectively, and a higher median age in the early group (76 vs. 67 years). The real-world progression-free survival (rwPFS) at 1 year was 70.5% in the early group and 88.9% in the late group (P = 0.31). Median rwPFS was 32.7 and 24.6 months (P = 0.98), and the median overall survival was 46.9 versus not reached in early and late groups, respectively (P = 0.17). Central nervous system rwPFS was not different between the early and late groups: 29.8 and 35.8 months, respectively (P = 0.39). We showed that a reduced dose of osimertinib within the first 3 months of treatment, compared to a later reduced dose, could influence treatment response or patient survival.

Radiation pneumonitis after concurrent aumolertinib and thoracic radiotherapy in EGFR-mutant non-small cell lung cancer patients

BACKGROUND

The superior efficacy of concurrent thoracic radiotherapy (TRT) and epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) has been proven in locally advanced and advanced non-small cell lung cancer (NSCLC) patients with EGFR mutations. However, the high incidence of radiation pneumonitis (RP) reduced by concurrent TRT and TKIs has attracted widespread attention. Thus, this study was designed to investigate the rate and risk factors for RP in EGFR-positive NSCLC patients simultaneously treated with aumolertinib and TRT.

METHODS

We retrospectively evaluated stage IIIA-IVB NSCLC patients treated with concurrent aumolertinib and TRT between May 2020 and December 2022 at Shandong Cancer Hospital and Institute, Shandong, China. RP was diagnosed by two senior radiologists and then graded from 1 to 5 according to the Common Terminology Criteria for Adverse Events v5.0. All risk factors were evaluated by univariate and multivariate logistic regression analyses.

RESULTS

A total of 49 patients were included, the incidence of grade ≥ 2 RP was 42.9%. Grade 2 and 3 RP were observed in 28.6% and 14.3% of patients, respectively. Grade 4 to 5 RP were not observed. the gross total volume (GTV) ≥ 21 ml and ipsilateral lung V20 ≥ 25% were risk factors for RP. The median progression-free survival (PFS) in the first-line therapy group and second-line therapy group were 23.5 months and 17.2 months, respectively (p = 0.10).

CONCLUSIONS

Better local control is achieved with concurrent TRT and aumolertinib, and special attention should be given to controlling ipsilateral lung V20 and GTV to reduce the risk of RP.

Liquid biopsy for the management of NSCLC patients under osimertinib treatment

Therapeutic management of NSCLC patients is quite challenging as they are mainly diagnosed at a late stage of disease, and they present a high heterogeneous molecular profile. Osimertinib changed the paradigm shift in treatment of EGFR mutant NSCLC patients achieving significantly better clinical outcomes. To date, osimertinib is successfully administered not only as first- or second-line treatment, but also as adjuvant treatment while its efficacy is currently investigated during neoadjuvant treatment or in stage III, unresectable EGFR mutant NSCLC patients. However, resistance to osimertinib may occur due to clonal evolution, under the pressure of the targeted therapy. The utilization of liquid biopsy as a minimally invasive tool provides insight into molecular heterogeneity of tumor clonal evolution and potent resistance mechanisms which may help to develop more suitable therapeutic approaches. Longitudinal monitoring of NSCLC patients through ctDNA or CTC analysis could reveal valuable information about clinical outcomes during osimertinib treatment. Therefore, several guidelines suggest that liquid biopsy in addition to tissue biopsy should be considered as a standard of care in the advanced NSCLC setting. This practice could significantly increase the number of NSCLC patients that will eventually benefit from targeted therapies, such as EGFR TKIs.

Distinct Progression and Efficacy of First-Line Osimertinib Treatment According to Mutation Subtypes in Metastatic NSCLC Harboring EGFR Mutations

Introduction

Osimertinib (OSI), a third-generation EGFR tyrosine kinase inhibitor, is the standard treatment for patients with naive EGFR-mutant NSCLC. Nevertheless, information on how the mutation subtype affects disease progression after the failure of OSI treatment is scarce.

Methods

We retrospectively reviewed patients with EGFR-mutant NSCLC who received OSI as a first-line treatment between April 2015 and December 2021.

Results

This study included 229 patients. The objective response rate was 71%, with intracranial and extracranial response rates of 71% and 90%, respectively. The median progression-free survival was 23.3 mo (95% confidence interval [CI]: 19.6-26.7), and the median overall survival was 33.7 mo (95% CI: 31.3-58.6). Multivariate analysis revealed that the EGFR exon 21 L858R point mutation (L858R) (hazard ratio [HR] = 1.56, 95% CI: 1.04-2.34, p = 0.0328) and liver metastasis (HR = 2.63, 95% CI: 1.53-4.49, p = 0.0004) were significant predictors of progression-free survival in OSI treatment. The concomitant disease progression involving the central nervous system metastasis was significantly more common in patients with L858R (p = 0.048), whereas concomitant disease progression involving primary lesions was significantly more common in patients with exon 19 deletion mutation (p = 0.01). In addition, the probability of disease progression over time was higher for L858R compared with that for exon 19 deletion mutation, in patients with central nervous system metastasis (log-rank test, p = 0.027).

Conclusions

The mutation subtype had an impact not only on the clinical outcome of the first-line OSI treatment but also on progression patterns after OSI treatment in patients with NSCLC harboring EGFR mutations.

ITGB1 and DDR activation as novel mediators in acquired resistance to osimertinib and MEK inhibitors in EGFR-mutant NSCLC

Osimertinib is a third-generation tyrosine kinase inhibitor clinically approved for first-line treatment of EGFR-mutant non-small cell lung cancer (NSCLC) patients. Although an impressive drug response is initially observed, in most of tumors, resistance occurs after different time and an alternative therapeutic strategy to induce regression disease is currently lacking. The hyperactivation of MEK/MAPKs, is one the most common event identified in osimertinib-resistant (OR) NSCLC cells. However, in response to selective drug pressure, the occurrence of multiple mechanisms of resistance may contribute to treatment failure. In particular, the epithelial-to-mesenchymal transition (EMT) and the impaired DNA damage repair (DDR) pathways are recognized as additional cause of resistance in NSCLC thus promoting tumor progression. Here we showed that concurrent upregulation of ITGB1 and DDR family proteins may be associated with an increase of EMT pathways and linked to both osimertinib and MEK inhibitor resistance to cell death. Furthermore, this study demonstrated the existence of an interplay between ITGB1 and DDR and highlighted, for the first time, that combined treatment of MEK inhibitor with DDRi may be relevant to downregulate ITGB1 levels and increase cell death in OR NSCLC cells.

Localization of Sites of Osimertinib Action in Rat Intestine, Skin, and Lung by Immunohistochemistry

Osimertinib is a third-generation, irreversible tyrosine kinase inhibitor (TKI) of epidermal growth factor receptor (EGFR) that selectively inhibits both EGFR-TKI-sensitizing and EGFR T790M resistance mutations and has shown efficacy in patients with non-small-cell lung cancer. In this study, we created osimertinib-specific antibodies and developed an immunohistochemistry (IHC) for locating the sites of osimertinib action. Moreover, we located osimertinib-protein conjugates in intestinal, dermal, and lung tissues of rats, thereby using our IHC to visualize the sites of the adverse effects of osimertinib, including diarrhea, skin disorder, and interstitial pneumonia. This report is the first to elucidate the localization of the sites of action of osimertinib in the rat intestine, skin, and lung and is expected to help clarify the mechanism of osimertinib-induced adverse effects.

Circulating tumor DNA: current implementation issues and future challenges for clinical utility

Over the past decades, liquid biopsy, especially circulating tumor DNA (ctDNA), has received tremendous attention as a noninvasive detection approach for clinical applications, including early diagnosis of cancer and relapse, real-time therapeutic efficacy monitoring, potential target selection and investigation of drug resistance mechanisms. In recent years, the application of next-generation sequencing technology combined with AI technology has significantly improved the accuracy and sensitivity of liquid biopsy, enhancing its potential in solid tumors. However, the increasing integration of such promising tests to improve therapy decision making by oncologists still has complexities and challenges. Here, we propose a conceptual framework of ctDNA technologies and clinical utilities based on bibliometrics and highlight current challenges and future directions, especially in clinical applications such as early detection, minimal residual disease detection, targeted therapy, and immunotherapy. We also discuss the necessities of developing a dynamic field of translational cancer research and rigorous clinical studies that may support therapeutic strategy decision making in the near future.

CYP450 and drug efflux transporters polymorphism influence clinical outcomes of Thai osimertinib-treated non-small cell lung cancer patients

Background: Osimertinib has shown greater efficacy than standard epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) and fewer grade 3 or higher adverse drug reactions (ADRs) in patients with advanced non-small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) mutations. However, the clinical outcomes of osimertinib treatment vary depending on the patient's ethnicity. Therefore, further research is necessary to evaluate the impact of single nucleotide polymorphisms (SNPs) in cytochrome P450 (CYP450) and drug transporters on the therapeutic outcomes and ADRs to osimertinib in Thai patients, to provide improved pharmacological treatments for cancer patients. Methods: This retrospective and prospective cohort study enrolled 63 Thai patients with NSCLC treated with 80 mg of osimertinib once daily as monotherapy. Seventeen SNPs in candidate genes related to drug metabolism and transport pathways were analyzed in each patient. Chi-square or Fisher's exact tests were used to evaluate the associations between SNPs and clinical outcomes, including ADR incidence and objective response rate (ORR). In addition, the correlation between the genotype and median time to treatment failure (TTF) or progression-free survival (PFS) was assessed using Kaplan-Meier analysis and a log-rank test. Results: We identified six SNPs (rs2231142 and rs2622604 in ABCG2, rs762551 in CYP1A2, rs1057910 in CYP2C9, rs28371759 in CYP3A4, and CYP2A6 deletion polymorphism (CYP2A6*4)) that significantly increased the incidence of ADRs. In addition, we found two SNPs (rs2069514 in CYP1A2 and rs1057910 in CYP2C9) that significantly decreased the median TTF, and two SNPs (rs28399433 in CYP2A6 and rs1057910 in CYP2C9) that significantly decreased the median progression-free survival (PFS). Specifically, we found that one of these SNPs (rs1057910 in CYP2C9) influenced ADRs, TTF, and PFS. Additionally, SNPs in the CYP2A6 heterozygous variant (non4/*4) significantly increased ADR incidence, leading to a high frequency of dose reduction (27.0%). Conclusion: Our study demonstrated significant SNPs associated with increased ADR incidence, decreased PFS, and decreased TTF in Thai patients with NSCLC treated with osimertinib. The CYP2C9 (*3) and CYP2A6 (*4) allele frequencies differed between ethnicities and were associated with an increased incidence of ADRs. These findings highlight the importance of considering genetic factors in NSCLC treatment and may facilitate personalized medicine approaches. Moreover, our study showed a higher incidence of ADRs than the previous trials, including FLAURA and AURA2, and a higher frequency of dose reduction than reported in the AURA 3 trial, possibly due to genetic differences among the study populations.

CT Radiomics Predict EGFR-T790M Resistance Mutation in Advanced Non-Small Cell Lung Cancer Patients After Progression on First-line EGFR-TKI

RATIONALE AND OBJECTIVES

We aim to explore the value of chest CT radiomics in predicting the epidermal growth factor receptor (EGFR)-T790M resistance mutation of advanced non-small cell lung cancer (NSCLC) patients after the failure of first-line EGFR-tyrosine kinase inhibitor (EGFR-TKI).

MATERIALS AND METHODS

A total of 211 and 135 advanced NSCLC patients with tumor tissue-based (Cohort-1) or circulating tumor DNA (ctDNA)-based (Cohort-2) EGFR-T790M testing were included, respectively. Cohort-1 was used for modeling and Cohort-2 was for models' validation. Radiomic features were extracted from tumor lesions on chest nonenhanced CT (NECT) and/or contrast-enhanced CT (CECT). We used eight feature selectors and eight classifier algorithms to establish radiomic models. Models were evaluated by area under the receiver operating characteristic curve (AUC), calibration curve, and decision curve analysis (DCA).

RESULTS

CT morphological manifestations of peripheral location and pleural indentation sign were associated with EGFR-T790M. For NECT, CECT, and NECT+CECT radiomic features, the feature selector and classifier algorithms of LASSO and Stepwise logistic regression, Boruta and SVM, and LASSO and SVM were chosen to develop the optimal model, respectively (AUC: 0.844, 0.811, and 0.897). All models performed well in calibration curves and DCA. Independent validation of models in Cohort-2 revealed that both NECT and CECT models individually had limited power for predicting EGFR-T790M mutation detected by ctDNA (AUC: 0.649, 0.675), while the NECT+CECT radiomic model had a satisfactory AUC (0.760).

CONCLUSION

This study proved the feasibility of using CT radiomic features to predict the EGFR-T790M resistance mutation, which could be helpful in guiding personalized therapeutic strategies.

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

BACKGROUND

Despite the well-established efficacies of tyrosine kinase inhibitors (TKIs) in epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC), there is limited real-world evidence comparing their effectiveness according to patients' clinical characteristics. This network meta-analysis (NMA) compared survival outcomes among first-line EGFR-TKIs in different subgroups of East Asian patients with advanced NSCLC.

METHODS

This NMA included real-world observational studies reporting outcomes with TKIs in patients aged >65 years, with baseline brain metastasis, with different Eastern Cooperative Oncology Group (ECOG) statuses, or with different common EGFR mutation types.

RESULTS

In patients with the EGFR L858R mutation, afatinib resulted in significantly longer progression-free survival (PFS) than erlotinib (hazard ratio [HR]: 0.59, 95% confidence interval [CI]: 0.46-0.75) and gefitinib (HR: 0.41, 95% CI: 0.32-0.53). Similarly, in patients with the EGFR Del19 mutation, afatinib and erlotinib resulted in significantly longer PFS than gefitinib (HR: 0.48 with 95% CI: 0.33-0.71 and HR: 0.54 with 95% CI: 0.36-0.80, respectively). Moreover, afatinib resulted in significantly longer PFS than gefitinib in patients with brain metastasis (HR: 0.53, 95% CI: 0.33-0.87) or ECOG status 0-1 (HR: 0.37, 95% CI: 0.23-0.59).

CONCLUSION

This NMA suggests that afatinib results in similar PFS to erlotinib and superior PFS than gefitinib in patients with Del19 mutant NSCLC, aged ≥65 years, with ECOG scores of 0-1, and with baseline brain metastasis.

Colonic mucosal diffuse congestion associated with Osimertinib

INTRODUCTION

Non-small cell lung cancer (NSCLC) is the most common histological subtype of lung cancer. Osimertinib has been recommended as first-line treatment of advanced NSCLC with EGFR mutations. Previous studies have only reported cases of gastrointestinal bleeding due to Erlotinib and gefitinib, but to date, always no cases of gastrointestinal bleeding due to Osimertinib have been reported.

CASE REPORT

We report a case of a female patient with NSCLC with EFGR mutation. After 1.5 years of treatment with Osimertinib, a colonoscopy showed diffuse congestion of the colonic mucosa.

MANAGEMENT AND OUTCOME

The patient's symptoms of blood in the stool disappeared, after stopping Osimertinib and giving mucosal protection treatment for 1 week.

DISCUSSION

Osimertinib may have contributed to gastrointestinal bleeding because no recurrent bleeding was observed after discontinuation of treatment. Physicians and patients should be aware that osimertinib may increase the risk of gastrointestinal bleeding.

Almonertinib plus chemotherapy versus almonertinib alone in second-line treatment of advanced non-small cell lung cancer with mutated epidermal growth factor receptor: a retrospective study

Objective

This study mainly observes the efficacy and safety of almonertinib plus chemotherapy compared with almonertinib alone in the second-line treatment of advanced non-small cell lung cancer (NSCLC) with mutated epidermal growth factor receptor (EGFR).

Methods

In this study, clinical data of 68 patients with advanced NSCLC who were treated in Jiangsu Provincial People's Hospital and Nanjing Chest Hospital between April 2020 and December 2022 were collected. Among them, the study group (n=30) received second-line almonertinib combined with platinum-based chemotherapy, while the control group (n=38) received almonertinib alone. The near-term and long-term effects and adverse events of the two groups were compared respectively.

Results

The median follow-up time until 31 December 2022 was 16.3 months (95% CI: 11.32-21.34). Results of chi-square analysis showed no statistically significant difference in objective response rate (ORR) and disease control rate (DCR) between the study group and the control group (56.73% vs. 55.3%, P>0.05; 100% vs. 86.8%, P>0.05). Log-rank test comparing the two groups revealed that the median progression-free survival (mPFS) of the study group was significantly longer than that of the control group by 3.1 months (12.7 vs. 9.6 months, P=0.01). Multivariate COX proportional risk model showed a statistically significant effect of treatment method and PS score on PFS (HR=0.43, P=0.023; HR=3.82, P=0.001). In terms of safety, most of the adverse events (AEs) were mild, with no grade 4-5 in the two groups, and the overall tolerance of patients was good.

Conclusion

For advanced NSCLC patients with EGFR mutations, second-line treatment with almonertinib plus chemotherapy significantly improved PFS compared with almonertinib alone without a significant increase in adverse events, providing efficacy and safety.

Real-world evidence of osimertinib in Chinese patients with EGFR T790M-positive non-small cell lung cancer: a subgroup analysis from ASTRIS study

PURPOSE

ASTRIS study aimed the largest to evaluate the effectiveness and safety of second- or higher-line osimertinib in patients with advanced/metastatic epidermal growth factor receptor (EGFR) T790M mutation-positive non-small cell lung cancer (NSCLC) in the real-world setting. Here we report the results of Chinese patients in ASTRIS study.

METHODS

Adults with EGFR T790M-positive advanced NSCLC pretreated with EGFR-tyrosine kinase inhibitor (EGFR-TKI), having a WHO performance status score of 0-2 and asymptomatic, stable central nervous system (CNS) metastases were included. All patients received once-daily osimertinib 80 mg orally. The outcomes included investigator-assessed clinical response, progression-free survival (PFS), time-to-treatment discontinuation (TTD), and safety.

RESULTS

A total of 1350 patients were included. Response rate was 55.7% (95% confidence interval [CI] 0.53-0.58). The median PFS and the median TTD were 11.7 months (95% CI 11.1-12.5) and 13.9 months (95% CI 13.1-15.2), respectively. Overall, 389 patients (28.8%) had at least one protocol-specified adverse event (AE); AEs of interstitial lung diseases/pneumonitis-like events and QT prolongation were reported in 3 (0.2%) and 59 (4.4%) patients, respectively.

CONCLUSION

Osimertinib was effective in Chinese patients with T790M-positive NSCLC who had progressed after first- or second-generation EGFR-TKI in real-word setting and the results were consistent with ASTRIS study overall population and AURA studies. No new safety signals or events were identified.

CLINICAL TRIAL NUMBER

NCT02474355.

A homologous and molecular dual-targeted biomimetic nanocarrier for EGFR-related non-small cell lung cancer therapy

The abnormal activation of epidermal growth factor receptor (EGFR) drives the development of non-small cell lung cancer (NSCLC). The EGFR-targeting tyrosine kinase inhibitor osimertinib is frequently used to clinically treat NSCLC and exhibits marked efficacy in patients with NSCLC who have an EGFR mutation. However, free osimertinib administration exhibits an inadequate response in vivo, with only ∼3% patients demonstrating a complete clinical response. Consequently, we designed a biomimetic nanoparticle (CMNP^@Osi) comprising a polymeric nanoparticle core and tumor cell-derived membrane-coated shell that combines membrane-mediated homologous and molecular targeting for targeted drug delivery, thereby supporting a dual-target strategy for enhancing osimertinib efficacy. After intravenous injection, CMNP^@Osi accumulates at tumor sites and displays enhanced uptake into cancer cells based on homologous targeting. Osimertinib is subsequently released into the cytoplasm, where it suppresses the phosphorylation of upstream EGFR and the downstream AKT signaling pathway and inhibits the proliferation of NSCLC cells. Thus, this dual-targeting strategy using a biomimetic nanocarrier can enhance molecular-targeted drug delivery and improve clinical efficacy.

Successful neoadjuvant treatment of EGFR exon 19 deletion combined with TP53 mutation in non-small cell lung cancer using aumolertinib after osimertinib-induced myocardial damage: a case report and literature review

The development of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) represents a paradigm shift in the treatment of lung cancer with EGFR mutations. Aumolertinib has been shown to be a safe agent in the registry study. However, successful rechallenge with aumolertinib following osimertinib-induced myocardial damage has not been reported. In this article, a case of neoadjuvant therapy for lung adenocarcinoma is retrospectively analyzed, and the relevant literature is reviewed. The patient was diagnosed with stage IIIA lung adenocarcinoma, and genetic testing revealed EGFR exon 19 deletion mutation combined with Tumor Protein p53 (TP53) mutation. The mutation abundance is 33.5 and 14%, respectively. One month after osimertinib treatment, the patient developed myocardial damage, and abnormal indicators such as myocardial enzyme spectrum showed abnormalities and cardiac insufficiency, followed by pulmonary hypertension and pulmonary edema. Aumolertinib was subsequently used for treatment, following which the myocardial enzyme spectrum returned to normal, and the symptoms of bilateral interstitial edema disappeared. In addition to the disappearance of adverse reactions, the therapeutic effect was excellent; the lung lesions and mediastinal lymph nodes were significantly reduced, and the operation was successfully conducted. This is the first report of successful neoadjuvant treatment of EGFR exon 19 deletion combined with TP53 mutation in NSCLC using aumolertinib after osimertinib-induced myocardial damage. The results suggested that aumolertinib had fewer adverse reactions in patients with EGFR exon 19 deletion combined with TP53 mutation, and aumolertinib may be a potential neoadjuvant therapy for stage IIIA lung cancer.

Clinical outcomes of chemotherapy in cancer patients with different ethnicities

BACKGROUND

Choosing the most effective chemotherapeutic agent with safest side effect profile is a common challenge in cancer treatment. Although there are standardized chemotherapy protocols in place, protocol changes made after extensive clinical trials demonstrate significant improvement in the efficacy and tolerability of certain drugs. The pharmacokinetics, pharmacodynamics, and tolerance of anti-cancer medications are all highly individualized. A driving force behind these differences lies within a person's genetic makeup.

RECENT FINDINGS

Pharmacogenomics, the study of how an individual's genes impact the processing and action of a drug, can optimize drug responsiveness and reduce toxicities by creating a customized medication regimen. However, these differences are rarely considered in the initial determination of standardized chemotherapeutic protocols and treatment algorithms. Because pharmacoethnicity is influenced by both genetic and nongenetic variables, clinical data highlighting disparities in the frequency of polymorphisms between different ethnicities is steadily growing.  Recent data suggests that ethnic variations in the expression of allelic variants may result in different pharmacokinetic properties of the anti-cancer medication. In this article, the clinical outcomes of various chemotherapy classes in patients of different ethnicities were reviewed.

CONCLUSION

Genetic and nongenetic variables contribute to the interindividual variability in response to chemotherapeutic drugs. Considering pharmacoethnicity in the initial determination of standard chemotherapeutic protocols and treatment algorithms can lead to better clinical outcomes of patients of different ethnicities.

Using cfDNA and ctDNA as Oncologic Markers: A Path to Clinical Validation

The detection of circulating tumor DNA (ctDNA) in liquid biopsy samples as an oncological marker is being used in clinical trials at every step of clinical management. As ctDNA-based liquid biopsy kits are developed and used in clinics, companies work towards increased convenience, accuracy, and cost over solid biopsies and other oncological markers. The technology used to differentiate ctDNA and cell-free DNA (cfDNA) continues to improve with new tests and methodologies being able to detect down to mutant allele frequencies of 0.001% or 1/100,000 copies. Recognizing this development in technology, the FDA has recently given pre-market approval and breakthrough device designations to multiple companies. The purpose of this review is to look at the utility of measuring total cfDNA, techniques used to differentiate ctDNA from cfDNA, and the utility of different ctDNA-based liquid biopsy kits using relevant articles from PubMed, clinicaltrials.gov, FDA approvals, and company newsletters. Measuring total cfDNA could be a cost-effective, viable prognostic marker, but various factors do not favor it as a monitoring tool during chemotherapy. While there may be a place in the clinic for measuring total cfDNA in the future, the lack of standardization means that it is difficult to move forward with large-scale clinical validation studies currently. While the detection of ctDNA has promising standardized liquid biopsy kits from various companies with large clinical trials ongoing, their applications in screening and minimal residual disease can suffer from lower sensitivity. However, researchers are working towards solutions to these issues with innovations in technology, multi-omics, and sampling. With great promise, further research is needed before liquid biopsies can be recommended for everyday clinical management.

Monitoring of Plasma EGFR Mutations during Osimertinib Treatment for NSCLC Patients with Acquired T790M Mutation

BACKGROUND

Osimertinib was first approved for the treatment of non-small cell lung cancer (NSCLC) in patients who have developed the epidermal growth factor receptor (EGFR) T790M mutation after treatment with EGFR tyrosine kinase inhibitors (TKIs). We routinely evaluated the plasma of NSCLC patients with the T790M mutation to more rapidly detect an increase in disease activity and resistance to treatment.

METHODS

Eligible patients received osimertinib after resistance to the first- or second-generation of EGFR-TKIs in NSCLC harboring T790M mutation detectable in tumor tissue or plasma. Plasma samples were collected every 8 weeks during osimertinib treatment. The plasma analysis was performed using an improved PNA-LNA PCR clamp method. We tested samples for a resistance mechanism, including EGFR-activating, T790M, and C797S mutations, and assessed the association between the mutations and osimertinib treatment.

RESULTS

Of the 60 patients enrolled in the study, 58 were eligible for this analysis. In plasma collected before osimertinib treatment, activating mutations were detected in 47 of 58 patients (81.0%) and T790M was detected in 44 patients (75.9%). Activating mutations were cleared in 60.9% (28/46) and T790M was cleared in 93.0% (40/43). Of these, 71.4% (20/28) of activating mutations and 87.5% (35/40) of T790M mutation were cleared within 8 weeks of treatment. The total response rate (RR) was 53.4% (31/58). The median duration of treatment was 259 days, with a trend toward longer treatment duration in patients who experienced the clearance of activating mutations with osimertinib. At the time of disease progression during osimertinib treatment, C797S was detected in 3 of 37 patients (8.1%).

CONCLUSION

Plasma EGFR mutation analysis was effective in predicting the effect of osimertinib treatment.

BBT-176, a Novel Fourth-Generation Tyrosine Kinase Inhibitor for Osimertinib-Resistant EGFR Mutations in Non-Small Cell Lung Cancer

PURPOSE

Resistance to third-generation EGFR inhibitors including osimertinib arises in part from the C797S mutation in EGFR. Currently, no targeted treatment option is available for these patients. We have developed a new EGFR tyrosine kinase inhibitor (TKI), BBT-176, targeting the C797S mutation.

PATIENTS AND METHODS

Recombinant EGFR proteins and Ba/F3 cell lines, patient-derived cells, and patient-derived xenografts expressing mutant EGFRs were used to test the inhibitory potency and the anticancer efficacy of BBT-176 both in vitro and in vivo. Patient case data are also available from an ongoing phase I clinical trial (NCT04820023).

RESULTS

The half maximal inhibitory concentration (IC50) of BBT-176 against EGFR 19Del/C797S, EGFR 19Del/T790M/C797S, and EGFR L858R/C797S proteins were measured at 4.36, 1.79, and 5.35 nmol/L, respectively (vs. 304.39, 124.82, and 573.72 nmol/L, for osimertinib). IC50 values of BBT-176 against Ba/F3 cells expressing EGFR 19Del/C797S, EGFR 19Del/T790M/C797S, EGFR L858R/C797S, and EGFR L858R/T790M/C797S were 42, 49, 183, and 202 nmol/L, respectively (vs. 869, 1,134, 2,799, and 2,685 nmol/L for osimertinib). N-ethyl-N-nitrosourea mutagenesis suggested that BBT-176 treatment does not introduce any secondary mutations in the EGFR gene but increases EGFR expression levels. Combined with the EGFR antibody cetuximab, BBT-176 effectively suppressed the growth of BBT-176-resistant clones. BBT-176 strongly inhibited the tumor growth, and in some conditions induced tumor regression in mouse models. In the clinical trial, two patients harboring EGFR 19Del/T790M/C797S in blood showed tumor shrinkage and radiologic improvements.

CONCLUSIONS

BBT-176 is a fourth-generation EGFR inhibitor showing promising preclinical activity against NSCLC resistant to current EGFR TKI, with early clinical efficacy and safety.

Osimertinib for an Advanced NSCLC Patient with Two Common EGFR Mutations and a Concomitant MET Exon 14 Skipping Mutation: A Case Report

Background

Lung cancer remains the leading cause of cancer-related mortality. Studies have revealed that a combination of crizotinib and EGFR tyrosine kinase inhibitors (TKIs) could be an effective treatment option for patients with sensitizing EGFR mutations and de novo or acquired MET amplification. Until now, there have been few reports of the response in patients harboring three mutations.

Case Presentation

A patient was diagnosed with advanced lung adenocarcinoma harboring EGFR Del19, L858R mutation and METex14. She received osimertinib, and repeated imaging revealed further tumor progression. Sixty-six days later, combined treatment with osimertinib and crizotinib was initiated. Unfortunately, the patient succumbed to death at home after 17 days.

Conclusion

This report firstly provided a lung adenocarcinoma patient with two common EGFR mutations (Del19 and L858R) and METex14. Our case raises a reminder about the tolerance and safety of combination therapy, especially in older peoples.

Epidermal Growth Factor Receptor T790M Mutation Testing in Non-Small Cell Lung Cancer: An International Collaborative Study to Assess Molecular EGFR T790M Testing in Liquid Biopsy

BACKGROUND

The detection of the EGFR T790M (T790M) mutation in non-small cell lung cancer (NSCLC) patients who progressed under treatment with first- or second-generation EGFR-tyrosine kinase inhibitors (TKIs) is important to offer a subsequent therapy with a third-generation EGFR-TKI. Liquid biopsy is a powerful tool to determine the T790M mutation status. Several liquid biopsy platforms with varying degrees of accuracy are available to test for T790M mutations, and sensitivities may differ among these methods.

METHODS

As no standard exists for the testing of T790M mutation in liquid biopsy, we performed a collaborative study to describe and compare the sensitivity of different in-house liquid biopsy platforms for the detection of the T790M mutation, EGFR exon 19 deletion (del19) and EGFR L858R mutation (L858R) across multiple participating laboratories in seven Central and Eastern European countries.

RESULTS

Of the 25 invited laboratories across Central and Eastern Europe, 21 centers participated and received 10 plasma samples spiked with cell-line DNA containing the T790M, del19, or L858R mutation in different concentrations. In-house PCR-based and NGS-based methods were used accordingly, and results were reported as in routine clinical practice. Two laboratories, which used the AmoyDx^® EGFR 29 Mutations Detection Kit (AmoyDx) with Cobas^® cfDNA Sample Preparation Kit and QX200 Droplet Digital PCR (ddPCR) with the QIAamp Circulating Nucleic Acid Kit identified all ten samples correctly. Cobas^® EGFR Mutation Test v2 (Cobas), the NGS methods, and the Idylla^TM detection method used in this study performed within the known sensitivity range of each detection method.

CONCLUSIONS

If a negative result was obtained from methods with lower sensitivity (e.g., Cobas), repeated liquid biopsy testing and/or tissue biopsy analysis should be performed whenever possible, to identify T790M-positive patients to allow them to receive the optimal second-line treatment with a third-generation EGFR TKI.

Successful osimertinib rechallenge after severe thrombocytopenia caused by osimertinib combined with sitagliptin: a case report

Osimertinib is recommended as the first-line treatment of advanced non-small cell lung cancer (NSCLC) in adults. The most commonly reported adverse events for osimertinib are skin effects, diarrhea, nausea, decreased appetite, fatigue, paronychia, and stomatitis. Severe thrombocytopenia is rarely reported. We present a case of severe thrombocytopenia in a 70-year-old NSCLC patient caused by osimertinib combined with sitagliptin. After remission of thrombocytopenia, the patient was well tolerated with osimertinib re-administration in the absence of sitagliptin. We speculated that declined platelet count might be related to the interaction between osimertinib and sitagliptin by acting with a synergistic effect on platelets. Osimertinib rechallenge can be considered after discontinuing drugs that may contribute to platelet decline if possible, and making a careful assessment of complete blood count and risk of bleeding.

Dynamics of disease progression during treatment with Osimertinib in patients with EGFR T790M-positive non-small cell lung cancer

BACKGROUND

Patterns of treatment failure and subsequent treatment in non-small cell lung cancer (NSCLC) patients treated with osimertinib are scarcely known. We analyzed the disease progression during osimertinib treatment to identify potential treatment strategies.

METHODS

We identified advanced NSCLC patients who commenced osimertinib treatment after progression on previous epidermal growth factor receptor (EGFR)-tyrosine-kinase inhibitor (TKI) from June 2014 to November 2018 from electronic records. Patients' tumor characteristics, efficacy outcomes, affected organs from radiology studies, and treatment modalities before and after osimertinib were analyzed.

RESULTS

Eighty-four patients were included. At osimertinib initiation, bone (50.0%) and brain (41.9%) were the commonest single metastatic sites, whereas thoracic involvement (73.3%) was more frequent than bone (27.4%) or brain (20.2%) metastasis during disease progression on osimertinib. Oligo-progressive disease (PD) and central nervous system (CNS)-sanctuary PD were observed in 15 (17.9%) and 3 (3.6%) patients, respectively. Most patients without brain metastasis (BM) at osimertinib initiation remained BM-free (46/49, 93.9%), and 60% of patients (21/35) with pre-existing BM showed intracranial disease control despite extracranial PD. The resistance mechanisms to osimertinib were explored in 23 patients (27.4%), and T790M-loss was observed in 14 patients (60.9%) who had worse survival outcomes than those without T790M-loss (progression-free survival, 5.4 vs. 16.5 months, p = 0.02; overall survival, not reached, p = 0.03).

CONCLUSION

PD during osimertinib treatment occurred preferentially in the thorax and pre-existing sites. Extracranial PD prevailed over intracranial PD regardless of baseline BM and prior brain radiation. These results support osimertinib's intracranial efficacy and may guide treatment strategies for EGFR-mutated NSCLC with BM.

Central nervous system efficacy of rezivertinib (BPI-7711) in advanced NSCLC patients with EGFR T790M mutation: A pooled analysis of two clinical studies

BACKGROUND

Rezivertinib (BPI-7711) is a novel third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) which revealed the systematic and central nervous system (CNS) antitumor activities for EGFR T790M-mutated advanced NSCLC in previous clinical studies and is further analyzed here.

METHODS

Eligible patients from the previous phase I and phase IIb studies of rezivertinib were included for pooled analysis. Post-progressive patients who received a prescribed dosage (≥180 mg) of rezivertinib orally once daily were included in full analysis set (FAS), while those with stable, asymptomatic CNS lesions, including measurable and non-measurable ones at baseline were included in CNS full analysis set (cFAS). Patients with measurable CNS lesions were included in CNS evaluable for response set (cEFR). BICR-assessed CNS objective response rate (CNS-ORR), CNS disease control rate (CNS-DCR), CNS duration of response (CNS-DoR), CNS progression-free survival (CNS-PFS), and CNS depth of response (CNS-DepOR) were evaluated.

RESULTS

355 patients were included in FAS, among whom 150 and 45 patients were included in cFAS and cEFR. This pooled analysis showed the CNS-ORR was 32.0% (48/150; 95% CI: 24.6-40.1%) and the CNS-DCR was 42.0% (63/150; 95% CI: 34.0-50.3%) in cFAS, while that in cEFR were 68.9% (31/45; 95% CI: 53.4-81.8%) and 100% (45/45; 95% CI: 92.1-100.0%). In cEFR, the median CNS-DepOR and the mean of CNS-DepOR were -52.0% (range: -100.0 to 16.1%) and -46.8% (95% CI: -55.5 to -38.1%). In cFAS, the median CNS-DoR and CNS-PFS were 13.8 (95% CI: 9.6-not calculable [NC]) and 16.5 (95% CI: 13.7-NC) months.

CONCLUSIONS

Rezivertinib demonstrated encouraging clinical CNS efficacy among advanced NSCLC patients with EGFR T790M mutation and CNS metastases.

3-Phosphoinositide-dependent kinase 1 drives acquired resistance to osimertinib

Osimertinib sensitive and resistant NSCLC NCI-H1975 clones are used to model osimertinib acquired resistance in humanized and non-humanized mice and delineate potential resistance mechanisms. No new EGFR mutations or loss of the EGFR T790M mutation are found in resistant clones. Resistant tumors grown under continuous osimertinib pressure both in humanized and non-humanized mice show aggressive tumor regrowth which is significantly less sensitive to osimertinib as compared with parental tumors. 3-phosphoinositide-dependent kinase 1 (PDK1) is identified as a potential driver of osimertinib acquired resistance, and its selective inhibition by BX795 and CRISPR gene knock out, sensitizes resistant clones. In-vivo inhibition of PDK1 enhances the osimertinib sensitivity against osimertinib resistant xenograft and a patient derived xenograft (PDX) tumors. PDK1 knock-out dysregulates PI3K/Akt/mTOR signaling, promotes cell cycle arrest at the G1 phase. Yes-associated protein (YAP) and active-YAP are upregulated in resistant tumors, and PDK1 knock-out inhibits nuclear translocation of YAP. Higher expression of PDK1 and an association between PDK1 and YAP are found in patients with progressive disease following osimertinib treatment. PDK1 is a central upstream regulator of two critical drug resistance pathways: PI3K/AKT/mTOR and YAP.

Noninvasive genomic profiling of somatic mutations in oral cavity cancers

OBJECTIVES

Somatic mutations may predict prognosis, therapeutic response, or cancer progression. We evaluated targeted sequencing of oral rinse samples (ORS) for non-invasive mutational profiling of oral squamous cell carcinomas (OSCC).

MATERIALS AND METHODS

A custom hybrid capture panel targeting 42 frequently mutated genes in OSCC was used to identify DNA sequence variants in matched ORS and fresh-frozen tumors from 120 newly-diagnosed patients. Receiver operating characteristic (ROC) curves determined the optimal variant allele fraction (VAF) cutoff for variant discrimination in ORS. Behavioral, clinical, and analytical factors were evaluated for impacts on assay performance.

RESULTS

Half of tumors involved oral tongue (50 %), and a majority were T1-T2 tumor stage (55 %). Median depth of sequencing coverage was 260X for OSCC and 1,563X for ORS. Frequencies of single nucleotide variants (SNVs) at highly mutated genes (including TP53, FAT1, HRAS, NOTCH1, CDKN2A, CASP8, NFE2L2, and PIK3CA) in OSCC were highly correlated with TCGA data (R = 0.96, p = 2.5E-22). An ROC curve with area-under-the-curve (AUC) of 0.80 showed that, at an optimal VAF cutoff of 0.10 %, ORS provided 76 % sensitivity, 96 % specificity, but precision of only 2.6E-4. At this VAF cutoff, 206 of 270 SNVs in OSCC were detected in matched ORS. Sensitivity varied by patient, T stage and target gene. Neither downsampled ORS as matched control nor a naïve Bayesian classifier adjusting for sequencing bias appreciably improved assay performance.

CONCLUSION

Targeted sequencing of ORS provides moderate assay performance for noninvasive detection of SNVs in OSCC. Our findings strongly rationalize further clinical and laboratory optimization of this assay, including strategies to improve precision.

Incidence of Bone Metastases and Skeletal-Related Events in Patients With EGFR-Mutated NSCLC Treated With Osimertinib

Introduction

Bone metastases are frequent in patients with EGFR-mutated (EGFR+) NSCLC. Skeletal-related events (SREs) are common in these patients; however, no data on SRE in osimertinib-treated patients are reported. We investigated the development of bone metastases and SREs in patients with EGFR+ NSCLC treated with osimertinib.

Methods

This is a retrospective multicenter cohort study that included patients with metastatic EGFR+ NSCLC who were treated with osimertinib between February 2016 and September 2021. Demographics, bone metastases-related outcomes, SREs, treatment efficacy, and overall survival (OS) were collected.

Results

In total, 250 patients treated with osimertinib (43% first line) were included. Of the patients, 51% had bone metastases at initiation of osimertinib. Furthermore, 16% of the patients with bone metastases used bone-targeted agents. Median follow-up from initiation of osimertinib was 23.4 months (95% confidence interval [CI]: 19.9-26.9 mo). During osimertinib treatment, 10% developed new bone metastases or bone progression. Of the patients with bone metastases, 39% had more than or equal to one SREs: 28% developed first SRE before osimertinib treatment, 1% after, and 11% during. Median OS post-bone metastasis was 30.8 months (95% CI: 21.9-39.7). Median OS after first SRE was 31.1 months (95% CI: 15.8-46.5).

Conclusions

Bone metastases and SREs are frequent before and during treatment with osimertinib in EGFR+ NSCLC. Because of these findings and the long OS post-bone metastases, we advocate prescription of bone-targeted agents in these patients and recommend adding bone-specific end points in clinical trials.

Lazertinib in pretreated EGFR T790M-mutated advanced non-small cell lung cancer: A real-world multicenter study

INTRODUCTION

Lazertinib is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) that provides a high level of selectivity for sensitizing and p.Thr790Met (T790M) EGFR mutations. We aimed to collect real-world data regarding the efficacy and safety of lazertinib.

METHODS

This study included patients treated with lazertinib for T790M-mutated non-small cell lung cancer who had previously been treated with an EGFR-TKI. The primary outcome measure was progression-free survival (PFS). Additionally, this study evaluated overall survival (OS), time-to-treatment failure (TTF), duration of response (DOR), objective response rate (ORR) and disease control rate (DCR). Drug safety was also assessed.

RESULTS

In a study of 103 patients, 90 received lazertinib as a second- or third-line therapy. The ORR and DCR were 62.1% and 94.2%, respectively. The median follow-up duration was 11.1 months, and the median PFS period was 13.9 (95% confidence interval [CI], 11.0-not reached [NR]) months. OS, DOR, and TTF had not yet been determined. In a subgroup of 33 patients with evaluable brain metastases, the intracranial DCR and ORR were 93.5% and 57.6%, respectively. The median intracranial PFS period was 17.1 (95% CI, 13.9-NR) months. Approximately 17.5% of patients had dose modification or discontinuation due to adverse events, with the most common being grade 1 or 2 paresthesia.

CONCLUSIONS

The efficacy and safety of lazertinib were recapitulated in a real-world study reflecting routine clinical practice in Korea, showing durable disease control both systematically and intracranially, with manageable side effects.

Single-arm trials supporting the approval of anticancer medicinal products in the European Union: contextualization of trial results and observed clinical benefit

BACKGROUND

Single-arm trials (SATs) can sometimes be used to support marketing authorization of anticancer medicinal products in the European Union. The level and durability of antitumor activity of the product as well as context are important aspects to determine the relevance of trial results. The aim of this study is to provide details on the contextualization of trial results and to evaluate the magnitude of benefit of medicinal products approved based on SATs.

MATERIALS AND METHODS

We focused on anticancer medicinal products for solid tumors approved on the basis of SAT results (2012-2021). Data were retrieved from European public assessment reports and/or published literature. The benefit of these medicinal products was evaluated via the European Society for Medical Oncology (ESMO)-Magnitude of Clinical Benefit Scale (MCBS).

RESULTS

Eighteen medicinal products were approved based on 21 SATs-few medicinal products were supported by >1 SAT. For the majority of clinical trials, a clinically relevant treatment effect was (pre)specified (71.4%) and most often an accompanying sample size calculation was provided. For 10 studies, each testing a different medicinal product, a justification for the threshold for a clinically relevant treatment effect could be identified. At least 12 out of 18 applications included information to facilitate the contextualization of trial results, including six supportive studies. Of the pivotal SATs analyzed (n = 21), three were assigned an ESMO-MCBS score of 4, which corresponds to 'substantial' benefit.

CONCLUSIONS

The clinical relevance of the treatment effects shown by medicinal products for solid tumors tested in SATs is dependent on the effect size and context. To better facilitate regulatory decision making, prespecifying and motivating a clinically relevant effect and aligning the sample size to that effect is important. External controls may facilitate in the contextualization process, but the associated limitations must be addressed.

Acquired resistance mechanisms to osimertinib: The constant battle

Lung cancer is the leading cause of cancer-related mortality worldwide. Detectable driver mutations have now changed the course of lung cancer treatment with the emergence of targeted therapy as a novel strategy that widely improved lung cancer prognosis, especially in metastatic patients. Osimertinib (AZD9291) is an irreversible third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) used to treat stage IV EGFR-mutated non-small-cell lung cancer. It was initially designed to target both EGFR-activating mutations and the EGFR T790M mutation as well, which is the most common resistance mechanism to first- and second-generation EGFR-TKIs. Following the FLAURA trial, osimertinib is now widely used in the first-line setting. However, resistance to osimertinib inevitably develops, with numerous mechanisms leading to its resistance, classified into two main categories: EGFR-dependent and EGFR-independent mechanisms. While EGFR-dependent mechanisms consist mainly of the C797S EGFR mutation, EGFR-independent mechanisms include bypass pathways, oncogenic fusions, and phenotypic transformation, among others. This review summarizes the molecular resistance mechanisms to osimertinib, with the aim of identifying novel therapeutic approaches to overcome osimertinib resistance and improve patient outcome.

Identification of EGFR inhibitors as potential agents for cancer therapy: pharmacophore-based modeling, molecular docking, and molecular dynamics investigations

CONTEXT

As a member of a large family of proteins that together regulate various aspects of cell growth and development, the epidermal growth factor receptor (EGFR) is a validated target for the development of new drugs. Herein, we compiled a library of 62 compounds from the PubChem database with similar pharmacophores as osimertinib, which to our knowledge represents the only drug capable of overcoming EGFR-T790M-mutated NSCLC until date. Subsequently, we launched a docking-based virtual screening campaign against the EGFR kinase with the compiled chemical entities. The virtual screen identified 3 hit candidates (CID_126667097, CID_137660592, and CID_137659061) with lower binding energy/higher affinity (- 8.7 kcal/mol, - 8.6 kcal/mol, and - 8.5 kcal/mol, respectively) than the standard osimertinib (- 8.4 kcal/mol). Molecular dynamics metrics such as RMSD, RMSF, ROG, and intermolecular H-bond were used to substantiate the stability of the promising drug candidates at the binding pocket of EGFR after 100,000 ps production run. Overall, our molecular modeling study portrayed CID_126667097, CID_137660592, and CID_137659061 as lead-like drug candidates that may be further developed for the treatment of EGFR-associated cancer disease.

METHODS

Molecular docking was conducted with Autodock Vina. A total of 62 compounds were compiled for the docking screen, which were then downloaded in SMILE format and converted to Protein Data Bank (PDB) format using the Openbabel online server. Finally, Gromacs 2022.3 was used to perform MD simulation to substantiate the stability of the hit candidates.

Hepatotoxicity of Small Molecule Protein Kinase Inhibitors for Cancer

Small molecule protein kinase inhibitors (PKIs) have become an effective strategy for cancer patients. However, hepatotoxicity is a major safety concern of these drugs, since the majority are reported to increase transaminases, and few of them (Idelalisib, Lapatinib, Pazopanib, Pexidartinib, Ponatinib, Regorafenib, Sunitinib) have a boxed label warning. The exact rate of PKI-induced hepatoxicity is not well defined due to the fact that the majority of data arise from pre-registration or registration trials on fairly selected patients, and the post-marketing data are often based only on the most severe described cases, whereas most real practice studies do not include drug-related hepatotoxicity as an end point. Although these side effects are usually reversible by dose adjustment or therapy suspension, or by switching to an alternative PKI, and fatality is uncommon, all patients undergoing PKIs should be carefully pre-evaluated and monitored. The management of this complication requires an individually tailored reappraisal of the risk/benefit ratio, especially in patients who are responding to therapy. This review reports the currently available data on the risk and management of hepatotoxicity of all the approved PKIs.

Successful administration of low-dose almonertinib in a patient with lung adenocarcinoma after osimertinib-induced interstitial lung disease: a case report and literature review

Osimertinib, the third generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), is the standard treatment for nonsmall cell lung cancer with EGFR mutation. However, osimertinib-induced interstitial lung disease (OsiILD) is considered to be a serious adverse event, so some patients will have to discontinue the use of osimertinib due to OsiILD. Almonertinib is a novel third-generation EGFR-TKI. We herein report a patient who developed OsiILD after the use of osimertinib and then switched to almonertinib for further treatment with success. This is the first report of a successfull rechallenge with low-dose almonertinib after OsiILD. We also reviewed the literature to explore the possible risk factors and the subsequent treatment of OsiILD, suggesting that low-dose almonertinib may be an option for follow-up treatment of OsiILD.

Aumolertinib effectively reduces clinical symptoms of an EGFR L858R-mutant non-small cell lung cancer case coupled with osimertinib-induced severe thrombocytopenia: a case report

Replacement of first-generation or second-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) with third-generation EGFR-TKIs remains the current standard of care for T790M mutations in patients with non-small cell lung cancer. Osimertinib is one of the first third-generation EGFR-TKIs to be approved and is also the most widely studied in clinical research. There has been widespread concern about the adverse effects of osimertinib such as cardiotoxicity and interstitial lung disease, but few articles have reported severe thrombocytopenia after osimertinib treatment. This article reports a 64-year-old woman with non-small cell lung cancer initially diagnosed with cT2aN1M1a, EGFR p.L858R, who developed disease progression and T790M after 32 months of first-line treatment with gefitinib (250 mg/day) before switching to second-line treatment with osimertinib (80 mg/day). Severe thrombocytopenia and active bleeding occurred after treatment with osimertinib, which improved with recombinant human thrombopoietin and platelet transfusion. Treatment was replaced with aumolertinib (110 mg/day). After platelet stabilization with aumolertinib treatment in combination with chest radiotherapy, this patient had progression-free survival for 9 months and overall survival for over 45 months. In conclusion, from our experience, aumolertinib has good efficacy and mild adverse effects, and is a good choice for non-small cell lung cancer patients with T790M, especially for patients at high risk of thrombocytopenia.

Examination of the effectiveness of local therapy for oligo-recurrence of EGFR-mutated NSCLC

BACKGROUND

The effectiveness of local therapy has been reported in patients with oligo-recurrence of non-small cell lung cancer (NSCLC), a metachronous recurrence with a limited number of recurrences, which can be treated with local therapy. Conversely, remarkable progress has been made in systemic therapy for NSCLC with the advent of molecular targeted therapy. In particular, epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) are very effective in the treatment of EGFR-mutated NSCLC. There is currently no consensus on treatment for oligo-recurrence of EGFR-mutated NSCLC.

METHODS

From 2004 to 2014, 811 patients underwent complete resection for NSCLC at Kitasato University Hospital and, of these, 244 patients developed recurrence. Oligo-recurrence was defined as the presence of two or less recurrent lesions, and 34 patients presented with EGFR-mutated oligo-recurrence.

RESULTS

We retrospectively examined and compared the effects of EGFR-TKIs with those of radical local therapy in patients with oligo-recurrent EGFR-mutated NSCLC. The five-year post-recurrence survival (PRS) rates of patients with EGFR-mutated oligo-recurrence who received radical local therapy (n = 23) and those who did not (n = 11) were 59.4 and 45.5%, respectively (p = 0.777). Multivariate analysis revealed no favorable prognostic factors associated with prolonged PRS, and radical local therapies did not improve PRS in patients with oligo-recurrence (p = 0.551).

CONCLUSION

Radical local therapy did not affect PRS in patients with oligo-recurrent EGFR-mutated NSCLC. Even in cases of oligo-recurrence, the administration of local therapy in patients with EGFR-mutated NSCLC might be carefully considered.

The effect of EGFR-TKIs on survival in advanced non-small-cell lung cancer with EGFR mutations: A real-world study

BACKGROUND

Few large-scale studies have been published using real-world data related to overall survival (OS) improvements in advanced epidermal growth factor receptor (EGFR)-mutant lung cancer patients; therefore, little is known regarding the characteristics of patients who could benefit most from EGFR-tyrosine kinase inhibitors (TKIs). Our study aimed to assess whether EGFR-TKI treatment confers survival benefits among advanced non-small-cell lung cancer (NSCLC) patients harboring EGFR mutations in the Chinese population.

PATIENTS AND METHODS

A total of 6451 advanced NSCLC patients were diagnosed between January 1, 2013 and June 30, 2019 in Zhejiang Cancer Hospital. Ultimately, 2864 patients with a confirmed EGFR mutation genotype were enrolled in our study. OS was measured from the time of diagnosis of advanced NSCLC until death or last follow-up.

RESULTS

Median follow-up for OS of advanced EGFR-mutant NSCLC patients was 28.33 months in our study. Patients who received EGFR-TKIs demonstrated better survival compared to those without EGFR-TKI treatment (mOS: 29.77 vs. 22.97 months, p < 0.0001). A total of 451 patients switched to third-generation EGFR-TKI treatment and obtained a significantly better survival than those who adopted first-line third-generation EGFR-TKIs or those who did not receive third-generation EGFR-TKIs after disease progression with first- or second-generation EGFR-TKI treatment (mOS: 38.0 vs. 32.5 vs. 28.3 months, p < 0.0001). As for EGFR genotypes, patients with exon 19 deletion showed better OS, followed by those with L858R mutation (32.4 vs. 24.83 months, p = 0.0013). NGS versus PCR testing showed no statistical differences with respect to survival outcomes (mOS: 27.5 vs. 27.47 months, p = 0.6745).

CONCLUSION

Advanced EGFR-mutant patients treated with EGFR-TKIs obtained absolute superior survival in the Chinese population.

Treatment Strategies for Non-Small Cell Lung Cancer with Common EGFR Mutations: A Review of the History of EGFR TKIs Approval and Emerging Data

The development of targeted therapies over the past two decades has led to a dramatic change in the management of EGFR-mutant non-small cell lung cancer (NSCLC). While there are currently five approved EGFR tyrosine kinase inhibitors (TKIs) for treating EGFR-mutant NSCLC in the first-line setting, therapy selection after progression on EGFR TKIs remains complex. Multiple groups are investigating novel therapies and drug combinations to determine the optimal therapy and treatment sequence for these patients. In this review, we summarize the landmark trials and history of the approval of EGFR TKIs, their efficacy and tolerability, and the role of these therapies in patients with central nervous system metastasis. We also briefly discuss the mechanisms of resistance to EGFR TKIs, ongoing attempts to overcome resistance and improve outcomes, and finalize by offering treatment sequencing recommendations.

Efficacy of Osimertinib Continuation Plus Metronomic Oral Vinorelbine for EGFRmutant Advanced NSCLC Beyond Limited Progression on Osimertinib

BACKGROUND

Treatment options for advanced non-small-cell lung cancer (NSCLC) after osimertinib failure are limited, and osimertinib continuation is recommended for selected patients. Metronomic oral vinorelbine is an effective treatment with less toxicity for advanced NSCLC.

OBJECTIVE

The objective of the study was to investigate the effects of osimertinib plus metronomic oral vinorelbine on epidermal growth factor receptor (EGFR)-mutant advanced NSCLC beyond limited progression on osimertinib.

METHODS

We have reviewed the medical records of 28 patients with EGFR-mutant advanced NSCLC who had received osimertinib continuation plus metronomic oral vinorelbine beyond limited progression on osimertinib. We also evaluated the clinicopathological characteristics of enrolled patients, as well as the efficacy and toxicity of the treatment.

RESULTS

After a median follow-up period of 14.1 months, 57.1% (16/28) of cases showed NSCLC progression. The median progression-free survival (PFS) period under osimertinib plus metronomic oral vinorelbine was 9.4 months (95% confidence interval, 1.562-17.238 months), with a disease control rate of 89.3% and objective response rate of 17.9%. PFS did not differ between patients who had previously received osimertinib as first- (n = 16) and second-line (n = 12) therapy (median, 11.4 and 4.7 months, P = 0.391). In addition, the median PFS duration did not differ according to the efficacy (PFS2 ≥ 6 months vs. <6 months) of previous osimertinib monotherapy (median, 5.8 and 9.4 months, P = 0.677).

CONCLUSIONS

Osimertinib continuation in conjunction with metronomic oral vinorelbine may enable overcoming TKI resistance and prolong the survival of patients with EGFR-mutant advanced NSCLC beyond limited progression on osimertinib treatment.

Successful Rechallenge with Osimertinib following Osimertinib-Induced Ventricular Tachycardia: A Case Report

Osimertinib, a third-generation tyrosine kinase inhibitor, is the first-line treatment for metastatic non-small cell lung cancer (NSCLC) with sensitizing epidermal growth factor receptor (EGFR) mutations. It is known to cause drug-induced cardiotoxicity, including QT prolongation syndrome, heart failure, and ventricular arrhythmias, which can lead to sudden death. Once severe arrhythmias occur, it is difficult to continue osimertinib treatment. We report a case of a 66-year-old woman with recurrent NSCLC after concurrent chemoradiotherapy who experienced osimertinib-induced ventricular arrhythmia-causing syncope. The patient was initially treated with concurrent chemoradiotherapy, and genetic testing revealed EGFR exon 19 deletion. Three years following treatment initiation, the primary tumor progressed, and new bone metastases developed. The patient was diagnosed with recurrent NSCLC and was treated with targeted therapy with osimertinib. On the 10th day of osimertinib administration, syncope occurred. Electrocardiography showed polymorphic non-sustained ventricular tachycardia, which was believed to be the cause of syncope. The patient was switched to erlotinib. Two and a half years later, disease progression in the primary lesion was observed. A liquid biopsy revealed an EGFR T790M resistance mutation. Therefore, osimertinib (40 mg) was administered every alternate day. After confirming the absence of palpitations and arrhythmias on electrocardiogram, the osimertinib dosing was increased to 40 mg daily. Thereafter, no further events occurred, and tumor shrinkage was observed. Low-dose osimertinib rechallenge after induced ventricular arrhythmia may be considered an option under close monitoring; however, osimertinib rechallenge must be carefully selected based on the risk-benefit analysis.