Evaluation of plasma EGFR mutation as an early predictor of response of erlotinib plus bevacizumab treatment in the NEJ026 study

Osimertinib resistance prognostic gene signature: STRIP2 is associated with immune infiltration and tumor progression in lung adenocarcinoma

OBJECTIVE

Although the use of osimertinib can significantly improve the survival time of lung adenocarcinoma (LUAD) patients with epithelial growth factor receptor mutation, eventually drug resistance will limit the survival benefit of most patients. This study aimed to develop a novel prognostic predictive signature based on genes associated with osimertinib resistance.

METHODS

The differentially expressed genes (DEGs) associated with osimertinib resistance in LUAD were screened from Gene Expression Omnibus datasets and The Cancer Genome Atlas datasets. Multivariate cox regression was used to establish a prognostic signature, and then a nomogram was developed to predict the survival probability of LUAD patients. We used ROC curve and DCA curve to evaluate its clinical prediction accuracy and net benefit. In addition, the differentially expressed genes significantly associated with prognosis were selected for immune infiltration analysis and drug sensitivity analysis, and their roles in the progression of lung adenocarcinoma were verified by in vitro experiments.

RESULTS

Our evaluation results indicated that the new nomogram had higher clinical prediction accuracy and net benefit value than the TN nomogram. Further analysis showed that patients with low STRIP2 expression had a higher level of immune response, and may be more likely to benefit from immune checkpoint inhibitors and conventional antitumor drugs. This may help to select more precise and appropriate therapy for LUAD patients with osimertinib resistance. Furthermore, in vitro experiments showed that STRIP2 promoted the LUAD cells proliferation, migration and invasion. This further demonstrates the importance of this gene signature for prognostic prediction.

CONCLUSION

We developed a reliable prognostic model based on DEGs associated with osimertinib resistance and screened for biomarker that can predict the immune response in LUAD patients, which may help in the selection of treatment regimens after osimertinib resistance.

Characteristics and prognostic analysis of patients with detected KRAS mutations in resected lung adenocarcinomas by peptide nucleic acid-locked nucleic acid polymerase chain reaction (PNA-LNA PCR) clamp method

Background

Kirsten rat sarcoma virus (KRAS) gene mutations are a type of driver mutation discovered in the 1980s, but for a long time no molecular targeted drugs were available for them. Recently, sotorasib was developed as a molecular targeted drug for KRAS mutations. It is therefore necessary to identify the characteristics of patients with KRAS mutations.

Methods

This was the single-institution retrospective study. Surgically resected tumors from lung adenocarcinoma patients were collected at a single institution from June 2016 to September 2019. Peptide nucleic acid-locked nucleic acid polymerase chain reaction (PNA-LNA PCR) clamp analysis of KRAS G12X mutations was compared with analysis by therascreen KRAS RGQ kit. The association between KRAS mutation status and patient characteristics and prognosis was assessed.

Results

Among 499 lung adenocarcinomas, KRAS mutations were evaluated in 197 cases, excluding stage IV lung cancer and tumors with epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) mutations. KRAS G12X mutations were detected in 59 cases (29.9%). The highest frequency by gene mutation subtype was G12V in 23 cases (39.0%), followed by G12C in 16 cases (27.1%), G12D in 12 cases (20.3%), G12S in 4 cases (6.8%) and G12A in 2 cases. For the G12C mutation, the PNA-LNA PCR clamp and therascreen methods were consistent, but for the G12D and G12S mutations, the PNA-LNA PCR clamp method showed higher detection rates. In operable tumors, G12C mutations were more frequent in males, smokers, and patients with high expression of programmed death-ligand 1 (PD-L1), and had no correlation with prognosis.

Conclusions

By the PNA-LNA PCR clamp method, G12C mutation of surgical specimens was detected successfully. The PNA-LNA PCR clamp method is expected to be applied to the detection of druggable G12C mutations.

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.

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

BACKGROUND

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.

PATIENTS AND METHODS

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.

RESULTS

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%).

CONCLUSIONS

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.

Bevacizumab versus Ramucirumab in EGFR-Mutated Metastatic Non-Small-Cell Lung Cancer Patients: A Real-World Observational Study

The combination of bevacizumab or ramucirumab with epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) therapy, chemotherapy, or immunotherapy for non-small-cell lung cancer (NSCLC) patients with EGFR mutations could have survival benefits. However, no study, to date, has been conducted to compare the efficacy and safety of these two antiangiogenic therapies (AATs). Stage IIIB to IV EGFR-mutated NSCLC patients who received first-line EGFR-TKIs between January 2014 and May 2022 were enrolled. These patients were divided into two groups: those receiving bevacizumab and those receiving ramucirumab as a combination therapy in any line of treatment. Ninety-six patients were enrolled in this study's final analysis. The progression-free survival (PFS) of patients who received front-line AATs combined with EGFR-TKI therapy was longer than that of patients receiving later-line AATs combined with other therapies (19.6 vs. 10.0 months, p < 0.001). No difference in overall survival (OS) was observed between front-line and later-line therapy (non-reach vs. 44.0 months, p = 0.261). Patients who received these two different AATs did not differ in PFS (24.1 vs. 15.7 months, p = 0.454) and OS (48.6 vs. 43.0 months, p = 0.924). In addition, these two AATs showed similar frequencies of the T790M mutation (43.6% vs. 38.2%; p = 0.645). Multivariate Cox regression analysis indicated several AAT cycles as an independent good prognostic factor in OS. The incidence of some adverse events such as bleeding and hepatitis was higher for bevacizumab than for ramucirumab but it was not significant. Front-line AAT and EGFR-TKI combination therapy improved the PFS of stage IV EGFR-mutated NSCLC patients. The effectiveness and safety of the two AATs were similar.

Circulating tumor DNA detection in MRD assessment and diagnosis and treatment of non-small cell lung cancer

Circulating tumor DNA (ctDNA) has contributed immensely to the management of hematologic malignancy and is now considered a valuable detection tool for solid tumors. ctDNA can reflect the real-time tumor burden and be utilized for analyzing specific cancer mutations via liquid biopsy which is a non-invasive procedure that can be used with a relatively high frequency. Thus, many clinicians use ctDNA to assess minimal residual disease (MRD) and it serves as a prognostic and predictive biomarker for cancer therapy, especially for non-small cell lung cancer (NSCLC). Advanced methods have been developed to detect ctDNA, and recent clinical trials have shown the rationality and feasibility of ctDNA for identifying mutations and guiding treatments in NSCLC. Here, we have reviewed recently developed ctDNA detection methods and the importance of sequence analyses of ctDNA in NSCLC.

Dynamic Assessment of Tissue and Plasma EGFR-Activating and T790M Mutations with Droplet Digital PCR Assays for Monitoring Response and Resistance in Non-Small Cell Lung Cancers Treated with EGFR-TKIs

Assessing tumor EGFR mutation status is necessary for the proper management of patients with advanced non–small cell lung cancer (NSCLC). We evaluated the impact of dynamic analyses of the plasma and tissue EGFR mutation using ultra-sensitive droplet digital PCR (ddPCR) assays to manage NSCLC patients treated with EGFR tyrosine kinase inhibitors (EGFR-TKIs). Paired tumor tissues and plasma samples from 137 EGFR-mutated lung adenocarcinoma patients prior to the first-line EGFR-TKIs treatment (at baseline) and at disease progression were subjected to EGFR mutation analysis using ddPCR, together with the analyses of the clinicopathological characteristics and treatment outcomes. Patients with EGFR-activating mutations detected in baseline plasma were associated with bone metastasis (p = 0.002) and had shorter progression-free survival (12.9 vs. 17.7 months, p = 0.02) and overall survival (24.0 vs. 39.4 months, p = 0.02) compared to those without. Pre-treatment EGFR T790M mutation found in baseline tumor tissues of 28 patients (20.4%; 28/137) was significantly associated with brain metastasis (p = 0.005) and a shorter brain metastasis-free survival (p = 0.001). The presence of EGFR T790M mutations in baseline tumor tissues did not correlate with the emergence of acquired EGFR T790M mutations detected at progression. At disease progression, acquired EGFR T790M mutations were detected in 26.6% (21/79) of the plasma samples and 42.9% (15/35) of the rebiopsy tissues, with a concordance rate of 71.4% (25/35). The dynamic monitoring of tissue and plasma EGFR mutation status at baseline and progression using ddPCR has a clinical impact on the evaluation of EGFR-TKIs treatment efficacy and patient outcomes, as well as the emergence of resistance in NSCLC.

The different overall survival between single-agent EGFR-TKI treatment and with bevacizumab in non-small cell lung cancer patients with brain metastasis

Comparison of epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) monotherapy or with bevacizumab in real-world non-small cell lung cancer (NSCLC) patients was lacking. 310 patients of advanced NSCLC with common EGFR mutation receiving first-generation EGFR-TKI monotherapy or with bevacizumab were included and propensity-score matched. Progression-free survival (PFS), overall survival (OS) and secondary T790M mutation were analysed. Patients receiving EGFR-TKI and bevacizumab were significantly younger, had better performance status and with high incidence of brain metastasis (55.8%). In the propensity-score matched cohort, PFS (13.5 vs. 13.7 months; log-rank p = 0.700) was similar between the two groups. The OS (61.3 vs. 34.2 months; log-rank p = 0.010) and risk reduction of death (HR 0.42 [95% CI 0.20–0.85]; p = 0.017) were significantly improved in EGFR-TKI plus bevacizumab group. Analysis of treatment by brain metastasis status demonstrated EGFR-TKI plus bevacizumab in patients with brain metastasis was associated with significant OS benefit compared to other groups (log-rank p = 0.030) and these patients had lower early-CNS and early-systemic progressions. The secondary T790M did not significantly differ between EGFR-TKI plus bevacizumab and EGFR-TKI monotherapy groups (66.7% vs. 75.0%, p = 0.460). Forty-one (31.1%) and 31 (23.5%) patients received subsequent osimertinib and chemotherapy, respectively. The post-progression OS of osimertinib and chemotherapy were 22.1 and 44.9 months in EGFR-TKI plus bevacizumab group and were 10.0 and 14.1 months in EGFR-TKI monotherpay group, respectively. First-generation EGFR-TKI with bevacizumab improved treatment efficacy in real-world patients of NSCLC with EGFR mutation. Patients with brain metastasis received additional OS benefit from this treatment.

Changes in the concentration of EGFR-mutated plasma DNA in the first hours of targeted therapy allow the prediction of tumor response in patients with EGFR-driven lung cancer

PURPOSE

This study aimed to analyze changes in the plasma concentration of EGFR-mutated circulating tumor DNA (ctDNA) occurring immediately after the start of therapy with EGFR tyrosine kinase inhibitors (TKIs).

METHODS

Serial plasma samples were collected from 30 patients with EGFR-driven non-small cell lung cancer before intake of the first tablet and at 0.5, 1, 2, 3, 6, 12, 24, 36 and 48 h after the start of the therapy. The content of EGFR alleles (exon 19 deletions or L858R) in ctDNA was measured by ddPCR.

RESULTS

ctDNA was detected at base-line in 25/30 (83%) subjects. Twelve (50%) out of 24 informative patients showed > 25% reduction of the ctDNA content at 48 h time point; all these patients demonstrated disease control after 4 and 8-12 weeks of therapy. The remaining 12 individuals showed either stable content of EGFR-mutated ctDNA (n = 5) or the elevation of ctDNA concentration (n = 7). 10 of 12 patients with elevated or stable ctDNA level achieved an objective response at 4 weeks, but only 5 of 10 evaluable patients still demonstrated disease control at 8-12 weeks (p = 0.032, when compared to the group with ctDNA decrease). The decline of the amount of circulating EGFR mutant copies at 48 h also correlated with longer progression-free survival (14.7 months vs. 8.5 months, p = 0.013).

CONCLUSION

Comparison of concentration of EGFR-mutated ctDNA at base-line and at 48 h after the start of therapy is predictive for the duration of TKI efficacy.

Monitoring of the presence of EGFR-mutated DNA during EGFR-targeted therapy may assist in the prediction of treatment outcome

The aim of our trial was to evaluate the prognostic significance of qualitative ctDNA analysis on different stages of EGFR mutated non-small cell lung cancer (NSCLC) treatment. We included 99 patients amendable for the first line treatment with either gefitinib/erlotinib (n = 87), afatinib (n = 10) or osimertinib (n = 2). Sequential qualitative analysis of ctDNA with cobas® EGFR Mutation Test v2 were performed before first dose, after 2 and 4 months of treatment, and on progression. Our analysis showed clinically significant heterogeneity of EGFR-mutated NSCLC treated with 1st line tyrosine kinase inhibitors (TKIs) in terms of progression-free and overall survival. When treated with conventional approach, i.e. monotherapy with TKIs, the patients falls into three subgroups based on ctDNA analysis before and after 2 months of treatment. Patients without detectable ctDNA at baseline (N = 32) possess the best prognosis on duration of treatment (PFS: 24.07 [16.8-31.3] and OS: 56.2 [21.8-90.7] months). Those who achieve clearance after two months of TKI (N = 42) have indistinguishably good PFS (19.0 [13.7 - 24.2]). Individuals who retain ctDNA after 2 months (N = 25) have the worst prognosis (PFS: 10.3 [7.0 - 13.5], p = 0.000). 9/25 patients did not develop ctDNA clearance at 4 months with no statistical difference in PFS from those without clearance at 2 months. Prognostic heterogeneity of EGFR-mutated NSCLC should be taken into consideration in planning further clinical trials and optimizing the outcome of patients.

Afatinib Treatment Alone or with Bevacizumab in a Real-World Cohort of Non-Small Cell Lung Cancer Patients with Epidermal Growth Factor Receptor Mutation

BACKGROUND

Treatment outcome between afatinib alone or with bevacizumab in non-small cell lung cancer (NSCLC) patient with epidermal growth factor receptor (EGFR) mutation remains insufficiently reported.

METHODS

A total of 405 advanced NSCLC patients with sensitizing-EGFR mutation receiving first-line single-agent afatinib or with bevacizumab were grouped and propensity score-matched. Progression-free survival (PFS), overall survival (OS) and secondary T790M mutation were analyzed.

RESULTS

In the original cohort, 367 (90.6%) patients received afatinib treatment alone and 38 (9.4%) patients received afatinib plus bevacizumab. Patients who received bevacizumab combination were significantly younger (54.6 ± 10.9 vs. 63.9 ± 11.5; p < 0.001) compared to the afatinib alone group. After propensity score matching, the afatinib alone and afatinib plus bevacizumab groups contained 118 and 34 patients, respectively. A non-significantly higher objective response was noted in the afatinib plus bevacizumab group (82.4% vs. 67.8%; p = 0.133). In the propensity score-matched cohort, a bevacizumab add-on offered no increased PFS (16.1 vs. 15.0 months; p = 0.500), risk reduction of progression (HR 0.85 [95% CI, 0.52-1.40]; p = 0.528), OS benefit (32.1 vs. 42.0 months; p = 0.700), nor risk reduction of death (HR 0.85 [95% CI, 0.42-1.74] p = 0.660) compared to the single-agent afatinib. The secondary T790M rate in afatinib plus bevacizumab and afatinib alone groups was similar (56.3% vs. 49.4%, p = 0.794). Multivariate analysis demonstrated that EGFR L858R (OR 0.51 [95% CI, 0.26-0.97]; p = 0.044), EGFR uncommon mutation (OR 0.14 [95% CI, 0.02-0.64]; p = 0.021), and PFS longer than 12 months (OR 2.71 [95% CI, 1.39-5.41]; p = 0.004) were independent predictors of secondary T790M positivity.

CONCLUSION

Bevacizumab treatment showed moderate efficacy in real-world, afatinib-treated NSCLC patients with EGFR-sensitizing mutation.

A Real-World Analysis of Patients with Untreated Metastatic Epidermal Growth Factor Receptor (EGFR)-Mutated Lung Adenocarcinoma Receiving First-Line Erlotinib and Bevacizumab Combination Therapy

INTRODUCTION

The clinical features of patients with metastatic epidermal growth factor receptor (EGFR)-mutated lung adenocarcinoma receiving first-line therapy based on erlotinib combined with bevacizumab are unclear. Here, we sought to analyze the clinical features of this patient group.

METHODS

Data were analyzed for the period from January 2015 to August 2019 for 49 patients with metastatic EGFR-mutated lung adenocarcinoma receiving first-line erlotinib-and-bevacizumab combination therapy from the Linkou and Kaohsiung Chang Gung Memorial Hospitals.

RESULTS

The combination of erlotinib and bevacizumab showed an 83.7% objective response rate and a 97.9% disease control rate. The median progression-free survival (PFS) and overall survival (OS) were 22.0 [95% CI (19.7-22.33)] and 47.6 [95% CI (38.87-56.37)] months, respectively, for all patients. The secondary EGFR-T790M mutation rate in the patients with acquired resistance to the combination was 72.4%. No predictive factor associated with the appearance of secondary EGFR-T790M mutations was found. The most frequent adverse event (AE) caused by the combination therapy was dermatitis (100%), and most of the AEs were manageable and grades 1 and 2.

CONCLUSION

Erlotinib combined with bevacizumab is an effective and safe therapy for untreated metastatic EGFR-mutated lung adenocarcinoma. The combination does not alter secondary EGFR-T790M mutations in patients with acquired resistance and is feasible in real-world clinical practice.

Current Therapeutic Strategies and Prospects for EGFR Mutation-Positive Lung Cancer Based on the Mechanisms Underlying Drug Resistance

The discovery of activating mutations in the epidermal growth factor receptor (EGFR) gene and the development of EGFR tyrosine kinase inhibitors (TKIs) have led to a paradigm shift in the treatment of non-small cell lung cancer (NSCLC). EGFR mutation-positive NSCLC is common in East Asia, and approximately 50% of adenocarcinomas harbor EGFR mutations. Undoubtedly, EGFR-TKIs, with their promising efficacy, are the mainstay of primary therapy. However, even if tumor shrinkage is achieved, most patients become resistant to EGFR-TKIs and relapse; hence, EGFR-TKIs do not achieve a radical cure. The problem of the development of resistance to targeted drugs has been a persistent challenge. After the role of EGFR T790M mutation in acquired drug resistance was reported, osimertinib, a third-generation irreversible EGFR-TKI, was designed to overcome the resistance conferred by T790M mutation. In addition, some studies have reported the mechanism of drug resistance caused by mutations other than the T790M mutation and strategies to overcome them. Elucidating the mechanism underlying drug resistance development and combining therapeutic approaches are expected to further improve NSCLC prognosis.

Osimertinib in poor performance status patients with T790M-positive advanced non-small-cell lung cancer after progression of first- and second-generation EGFR-TKI treatments (NEJ032B)

BACKGROUND

Osimertinib is effective in patients with T790M mutation-positive advanced non-small-cell lung cancer (NSCLC) resistant to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). However, its effectiveness and safety in patients with poor performance status (PS) are unknown.

METHODS

Enrolled patients showed disease progression after treatment with gefitinib, erlotinib, or afatinib; T790M mutation; stage IIIB, IV, or recurrent disease; and PS of 2-4. Osimertinib was orally administered at a dose of 80 mg/day. The primary endpoint of this phase II study (registration, jRCTs061180018) was response rate and the secondary endpoints were progression-free survival (PFS), overall survival (OS), disease control rate, and safety.

RESULTS

Thirty-three patients were enrolled, of which 69.7% and 24.2% had PS of 2 and 3, respectively. One patient was excluded due to protocol violation; in the remaining 32 patients, the response rate was 53.1%; disease control rate was 75.0%; PFS was 5.1 months; and OS was 10.0 months. The most frequent adverse event of grade 3 or higher severity was lymphopenia (12.1%). Interstitial lung disease (ILD) was observed at all grades and at grades 3-5 in 15.2% (5/33) and 6.1% (2/33) of patients, respectively. Treatment-related death due to ILD occurred in one patient. Patients negative for activating EGFR mutations after osimertinib administration had longer median PFS than those positive for these mutations.

CONCLUSION

Osimertinib was sufficiently effective in EGFR-TKI-resistant, poor PS patients with T790M mutation-positive advanced NSCLC. Plasma EGFR mutation clearance after TKI treatment could predict the response to EGFR-TKIs.

Bevacizumab plus erlotinib versus erlotinib alone in Japanese patients with advanced, metastatic, EGFR-mutant non-small-cell lung cancer (NEJ026): overall survival analysis of an open-label, randomised, multicentre, phase 3 trial

BACKGROUND

Bevacizumab is a promising candidate for combination treatment with epidermal growth factor receptor tyrosine-kinase inhibitors (eg, erlotinib), which could improve outcomes for patients with metastatic EGFR-mutant non-small-cell lung cancer (NSCLC). We have previously shown in NEJ026, a phase 3 trial, that the combination of bevacizumab plus erlotinib significantly prolonged progression-free survival compared with erlotinib alone in these patients. In further analyses, we aimed to examine the effects of bevacizumab-erlotinib on overall survival, time from enrolment to progressive disease during second-line treatment or death, and quality of life.

METHODS

This open-label, randomised, multicentre, phase 3 trial (NEJ026) was done in 69 hospitals and medical, community-based centres across Japan. Eligible patients had stage IIIB, stage IV, or postoperative recurrent, EGFR-mutant (exon 19 deletion or exon 21 Leu858Arg point mutation) NSCLC, had not previously received systemic chemotherapy, and were randomly assigned (1:1) by a computer-generated randomisation sequence and minimisation to receive either 150 mg oral erlotinib once daily plus 15 mg/kg intravenous bevacizumab once every 21 days, or 150 mg oral erlotinib once daily, until disease progression or intolerable toxicity. Randomisation was stratified according to sex, smoking status, EGFR mutation subtype, and clinical disease stage. All participants, investigators, and study personnel (including those assessing outcomes) were unmasked to treatment allocation. We report the secondary outcomes of overall survival and quality of life (the period from enrolment to confirmation of a minimally important difference on the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire [EORTC QLQ]-C30), and the exploratory outcome of time from enrolment to progressive disease during second-line treatment or death. Overall survival and the exploratory outcome were analysed in the modified intention-to-treat population, which comprised all randomly assigned patients who received at least one dose of the study drug and had response evaluations. Quality of life was analysed in patients in the modified intention-to-treat population who had completed the quality of life questionnaires. The trial is registered with the University Hospital Medical Information Network Clinical Trials Registry, UMIN000017069, and the Japan Registry of Clinical Trials, jRCTs031180056, and is currently closed.

FINDINGS

Between June 3, 2015, and Aug 31, 2016, 228 patients were enrolled. 112 patients who received bevacizumab-erlotinib and 112 who received erlotinib only were included in the modified intention-to-treat population. At data cutoff (Nov 30, 2019) and a median follow-up of 39·2 months (IQR 23·9-43·5), the median overall survival was 50·7 months (95% CI 37·3-not estimable [NE]) in the bevacizumab-erlotinib group and 46·2 months (38·2-NE) in the erlotinib-only group (hazard ratio [HR] 1·007, 95% CI 0·681-1·490; p=0·97). In analysis of the exploratory outcome, after a median follow-up of 23·9 months (IQR 14·2-39·1), the median time from enrolment to progressive disease during second-line treatment or death was 28·6 months (95% CI 22·1-35·9) in the bevacizumab-erlotinib group and 24·3 months (20·4-29·1) in the erlotinib-only group (HR 0·773, 95% CI 0·562-1·065). The median time between enrolment and confirmation of a minimally important difference on the EORTC QLQ-C30 was 6·0 months (95% CI 5·2-11·3) in the bevacizumab-erlotinib group and 8·3 months (5·7-13·9) in the erlotinib-only group (p=0·47).

INTERPRETATION

The addition of bevacizumab to erlotinib did not prolong survival in patients with metastatic EGFR-mutant NSCLC, but both treatment groups had relatively long survival durations. Why the addition of bevacizumab to erlotinib did not affect overall survival is unclear, but it is possible that the beneficial effects of combination therapy were not seen because overall survival was influenced by treatment regimens used after disease progression.

FUNDING

Chugai Pharmaceutical.

EGFR-plasma mutations in prognosis for non-small cell lung cancer treated with EGFR TKIs: A meta-analysis

BACKGROUND

The plasma-based epidermal growth factor receptor (EGFR) mutation testing is approved recently to use in clinical practice. However, it has not been used as a prognostic marker yet because of contradictory results.

AIM

This meta-analysis aims to clarify the role of the EGFR-plasma test in prognosis for non-small cell lung cancer (NSCLC) who have mutant tumors and receive EGFR tyrosine kinase inhibitors (TKIs).

METHODS AND RESULTS

The PubMed/MEDLINE, Web of Science, Cochrane Library, and Google Scholar databases were searched for relevant studies by April 10, 2021. The hazard ratio (HR) from reports was extracted and used to assess the correlation of EGFR-plasma status with progression-free survival (PFS) and overall survival (OS). A total of 35 eligible studies with 4106 patients were enrolled in the final analysis. Patients with concurrent EGFR mutations in pretreatment plasma have shorter PFS (HR = 2.00, 95% confidence interval [CI]: 1.73-2.31, p < .001) and OS time (HR = 2.31, 95% CI: 1.89-2.83, p < .001) compared to the tumor-only mutation cases. Besides, the persistence of EGFR-activating mutations in post-treatment plasma is associated with worse PFS (HR = 3.84, 95% CI: 2.96-4.99, p < .001) and OS outcome (HR = 3.22, 95% CI: 2.35-4.42, p < .001) compared to others. Notably, the prognostic value of the EGFR-plasma test is also validated in treatment with third-generation EGFR TKI and significance regardless of different detection methods.

CONCLUSION

The presence of EGFR-plasma mutations at pretreatment and after EGFR TKI initiation is the worse prognostic factor for PFS and OS in NSCLC.

Leveraging the Fragment Length of Circulating Tumour DNA to Improve Molecular Profiling of Solid Tumour Malignancies with Next-Generation Sequencing: A Pathway to Advanced Non-invasive Diagnostics in Precision Oncology?

Circulating cell-free DNA (ccfDNA) has emerged as a promising diagnostic tool in oncology. Identification of tumour-derived ccfDNA (i.e. circulating tumour DNA [ctDNA]) provides non-invasive access to a malignancy’s molecular landscape to diagnose, inform therapeutic strategies, and monitor treatment efficacy. Current applications of ccfDNA to detect somatic mutations, however, have been largely constrained to tumour-informed searches and identification of common mutations because of the interaction between ctDNA signal and next-generation sequencing (NGS) noise. Specifically, the low allele frequency of ctDNA associated with non-metastatic and early-stage lesions may be indistinguishable from artifacts that accrue during sample preparation and NGS. Thus, using ccfDNA to achieve non-invasive and personalized molecular profiling to optimize individual patient care is a highly sought goal that remains limited in clinical practice. There is growing evidence, however, that further advances in the field of ccfDNA diagnostics may be achieved by improving detection of somatic mutations through leveraging the inherently shorter fragment lengths of ctDNA compared to non-neoplastic ccfDNA. Here, the origins and rationale for seeking to improve the mutation-based detection of ctDNA by using ccfDNA size profiling are reviewed. Subsequently, in vitro and in silico methods to enrich for a target ccfDNA fragment length are detailed to identify current practices and provide perspective into the potential of using ccfDNA size profiling to impact clinical applications in oncology.

Real-world characteristics and outcomes of advanced non-small-cell lung cancer patients with EGFR exon 19 deletions or exon 21 mutations

Aim: To estimate real-world (rw) outcomes for first-line therapy in patients with advanced EGF receptor (EGFR)-mutated non-small-cell lung cancer (NSCLC), focusing on specific mutation types. Patients & methods: Retrospective observational study (n = 244 patients). Results: Univariate/multivariate analyses showed longer rw progression-free survival (rwPFS) and rwPFS2 in patients with ex19del versus Leu858Arg mutations. Median overall survival was 12.3 months longer with ex19del versus Leu858Arg mutations (HR: 1.47 [95% CI: 0.96-2.25]; p = 0.074). With EGFR-tyrosine kinase inhibitor monotherapy, unadjusted rwPFS for ex19del mutations was longer than for Leu858Arg mutations (HR: 1.62 [95% CI: 1.03-2.56]; p = 0.036). Conclusion: In this rw cohort of patients with advanced EGFR+ NSCLC, ex19del mutations conferred a prognostic advantage over Leu858Arg mutations, with significantly better rwPFS and rwPFS2.

Phase II open-label multicenter study to assess the antitumor activity of afatinib in lung cancer patients with activating epidermal growth factor receptor mutation from circulating tumor DNA: Liquid-Lung-A

BACKGROUND

Mutation analysis of circulating tumor DNA (ctDNA) is used for diagnosing lung cancer. This trial aimed to assess the efficacy of afatinib in treatment-naïve patients with lung cancer harboring epidermal growth factor receptor mutations (EGFRm, exon 19 deletions or exon 21 point mutations) detected based on ctDNA.

METHODS

The primary objective was the objective response rate (ORR) in the response evaluable (RE) population. EGFRm analysis of ctDNA was performed using PANA Mutype. Of the 331 patients screened, ctDNA was positive in 21% (68/331) in the detection of activating EGFRm. Among 81 subjects with tumor EGFRm, 48 showed matched EGFRm in their ctDNA (59% sensitivity).

RESULTS

Therapy with afatinib 40 mg was initiated in 21 (female, 17; adenocarcinoma, 20) patients (intention-to-treat, ITT); dose modifications were made in 15 (71%). The ORR was 74% in the RE population (14/19); 11 patients showed EGFRm only in ctDNA (Group A), whereas 10 exhibited the same EGFRm in their ctDNA and tumor DNA (Group B). There was no significant difference in ORR between Groups A and B (80% and 67% RE, respectively). Median progression-free survival (PFS) was 12.0 months, and no significant difference was observed according to the final afatinib dose, type of EGFRm, and Group A versus B. After progression, T790M mutation was found in 40% (6/15) of patients, and osimertinib was used as a second-line treatment.

CONCLUSIONS

Afatinib showed similar ORR and PFS in patients with lung cancer harboring EGFRm in their ctDNA regardless of tumor EGFRm results.

KEY POINTS

SIGNIFICANT FINDINGS OF THE STUDY: Afatinib showed favorable ORR and PFS regardless of the tumor EGFR mutation status results, similar to the findings of previous trials assessing afatinib as first-line treatment of EGFR-mutated non-small cell lung cancer based on tumor genotyping.

WHAT THIS STUDY ADDS

Our findings emphasize that the survival benefit of afatinib treatment can be achieved not only by appropriate dose reduction with frequent and detailed monitoring of toxicities, but also by using noninvasive (ctDNA) assays in a real-world setting.

Rational Application of First-Line EGFR-TKIs Combined with Antiangiogenic Inhibitors in Advanced EGFR-Mutant Non-Small-Cell Lung Cancer: A Systematic Review and Meta-Analysis

Purpose

A meta-analysis of randomized controlled trials (RCTs) was conducted to compare the difference in efficacy and safety between epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) with antiangiogenic inhibitors (A + T) and EGFR-TKI monotherapy in patients with treatment-naïve advanced EGFR-mutant non-small-cell lung cancer (NSCLC).

Methods

PubMed, Embase, Web of Science, and Cochrane electronic databases were searched for relevant RCTs. Meeting abstracts were also reviewed to identify appropriate studies. The endpoints included progression-free survival (PFS), overall survival (OS), 1- and 2-year OS rates, objective response rate (ORR), and grade ≥ 3 adverse events. All pooled outcomes were expressed using hazard ratios (HRs) or relative risk ratios (RRs).

Results

Data were collected from six eligible RCTs, which included 1,244 participants (619 in the A + T group and 625 in the TKI alone group). PFS was significantly improved with A + T compared to TKI alone (HR = 0.60; P < 0.01) regardless of EGFR mutation types (exon 19 deletion or L858R) and brain metastasis status (with or without brain metastases). There was no significant difference in median OS between the A + T and TKI alone groups (HR = 0.933; P = 0.551) regardless of EGFR mutation type. The ORR for A + T combination therapy was significantly increased compared to TKI monotherapy in exon 19 deletion subgroups (RR = 0.774; P = 0.008). There was no difference in the positive rates of acquired T790M mutation between the two groups (RR = 0.967; P = 0.846). More patients in the TKI alone group received a variety of subsequent systemic treatments than those in the A + T group (RR = 0.881; P = 0.002).

Conclusion

Addition of antiangiogenic inhibitors to first-line EGFR-TKI therapy significantly reduced the risk of disease progression for patients with advanced EGFR-mutant NSCLC regardless of EGFR mutation type and brain metastasis status. The lack of OS benefit may be explained by differences in subsequent treatments rather than drug resistance mechanisms.