Growth Factor Receptor T790M Mutation Research Articles

Development and validation of a deep learning-based model to predict response and survival of T790M mutant non-small cell lung cancer patients in early clinical phase trials using electronic medical record and pharmacokinetic data.

Epidermal growth factor receptor (EGFR) T790M mutation is the standard predictive biomarker for third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) treatment. While not all T790M-positive patients respond to third-generation EGFR-TKIs and have a good prognosis, it necessitates novel tools to supplement EGFR genotype detection for predicting efficacy and stratifying EGFR-mutant patients with various prognoses. Mixture-of-experts (MoE) is designed to disassemble a large model into many small models. Meanwhile, it is also a model ensembling method that can better capture multiple patterns of intrinsic subgroups of enrolled patients. Therefore, the combination of MoE and Cox algorithm has the potential to predict efficacy and stratify survival in non-small cell lung cancer (NSCLC) patients with EGFR mutations. We utilized the electronic medical record (EMR) and pharmacokinetic parameters of 326 T790M-mutated NSCLC patients, including 283 patients treated with Abivertinib in phase I (n=177, for training) and II (n=106, for validation) clinical trials and an additional validation cohort 2 comprising 43 patients treated with BPI-7711. Furthermore, 18 patients underwent whole-exome sequencing for biological interpretation of CoxMoE. We evaluated the predictive performance for therapeutic response using the area under the curve (AUC) and the Concordance index (C-index) for progression-free survival (PFS). CoxMoE exhibited AUCs of 0.73-0.83 for predicting efficacy defined by best overall response (BoR) and achieved C-index values of 0.64-0.65 for PFS prediction in training and validating cohorts. The PFS of 198 patients with a low risk [median, 6.0 (range, 1.0-23.3) months in the abivertinib treated cohort; median 16.5 (range, 1.4-27.4) months in BPI-7711 treated cohort] of being non-responder increased by 43% [hazard ratio (HR), 0.56; 95% confidence interval (CI), 0.40-0.78; P=0.0013] and 50% (HR, 0; 95% CI, 0-0; P=0.01) compared to those at high-risk [median, 4.2 (range, 1.0-35) months in the abivertinib treated cohort; median, 11.0 (range, 1.4-25.1) months in BPI-7711 treated cohort]. Additionally, activated partial thromboplastin time (APTT), creatinine clearance (Ccr), monocyte, and steady-state plasma trough concentration utilited to construct model were found significantly associated with drug resistance and aggressive tumor pathways. A robust correlation was observed between APTT and Ccr with PFS (log-rank test; P<0.01) and treatment response (Wilcoxon test; P<0.05), respectively. CoxMoE offers a valuable approach for patient selection by forecasting therapeutic response and PFS utilizing laboratory tests and pharmacokinetic parameters in the setting of early-phase clinical trials. Simultaneously, CoxMoE could predict the efficacy of third-generation EGFR-TKI non-invasively for T790M-positive NSCLC patients, thereby complementing existing EGFR genotype detection.

EGFR-T790M mutation associated with acquired resistance to first-generation EGFR tyrosine kinase inhibitors in Vietnamese Non-Small-Cell Lung Cancer patients

Background: non-small cell lung cancer (NSCLC) patients who had epidermal growth factor receptor (EGFR) mutations sensitive to EGFR tyrosine kinase inhibitors (TKIs) had a high response rate to target therapies. Epidermal growth factor receptor (EGFR) T790M mutation is the most common mechanism of acquired resistance to first-generation EGFR TKIs. Objective: The aim of this study was to analyze the incidence of EGFR T790 mutation, the progression-free survival (PFS) in the patients who progress on the first‑ generation EGFR‑TKIs. This study also investigates the correlation between T790M mutation and clinical, subclinical features, progression-free survival of NSCLC Vietnamese patients.&#x0D; Patients and methods: We analyzed 66 NSCLC patients who had acquired resistance to first-generation EGFR-TKIs. The clinical data, PFS and the mechanism of acquired resistance were obtained. The Kaplan-Meier method and the log-rank test were used to analyze the PFS and compare between subgroups of patient characteristics. The correlations between the patient’s characteristics and EGFR-T790M mutation status were analyzed by Chi-square and Fisher’s exact tests.&#x0D; Results: At the progressive period, EGFR T790M mutation was detected in 54.5% of patients. The median PFS were 14.48 ± 3.9 months (range: 8- 26 months). Patients who were older than 60 years old or had comorbidities had significantly shorter PFS than the subgroups without (P≤0.05). The age, gender, smoking status, comorbidities, pathological features were not significantly correlated with the development of EGFR-T790M (P &gt; 0.05). The average PFS was not significantly different between the EGFR-T790M group and the non-EGFR-T790M group (P=0.642).&#x0D; Conclusion: In our cohort study, more than half of all patients had T790M mutation after being treated with first-generation EGFR TKIs. Age and comorbidities were associated with PFS but the EGFR-T790M mutation was not correlated with PFS.

A Phase II trial of alternating osimertinib and gefitinib therapy in advanced EGFR-T790M positive non-small cell lung cancer: OSCILLATE

In this phase II, single arm trial (ACTRN12617000720314), we investigate if alternating osimertinib and gefitinib would delay the development of resistance to osimertinib in advanced, non-small cell lung cancer (NSCLC) with the epidermal growth factor receptor (EGFR) T790M mutation (n = 47) by modulating selective pressure on resistant clones. The primary endpoint is progression free-survival (PFS) rate at 12 months, and secondary endpoints include: feasibility of alternating therapy, overall response rate (ORR), overall survival (OS), and safety. The 12-month PFS rate is 38% (95% CI 27.5–55), not meeting the pre-specified primary endpoint. Serial circulating tumor DNA (ctDNA) analysis reveals decrease and clearance of the original activating EGFR and EGFR-T790M mutations which are prognostic of clinical outcomes. In 73% of participants, loss of T790M ctDNA is observed at progression and no participants have evidence of the EGFR C797S resistance mutation following the alternating regimen. These findings highlight the challenges of treatment strategies designed to modulate clonal evolution and the clinical importance of resistance mechanisms beyond suppression of selected genetic mutations in driving therapeutic escape to highly potent targeted therapies.

Detection of EGFR T790M mutation using liquid biopsy for non-small cell lung cancer: Utility of droplet digital polymerase chain reaction vs. cobas real-time polymerase chain reaction

BackgroundDigital platforms for mutation detection yield higher sensitivity than non-digital platforms but lack universal positive cut-off values that correlate with the outcome of osimertinib treatment. This study determined compared droplet digital polymerase chain reaction (ddPCR) to the standard cobas assay for epithelial growth factor receptor (EGFR) T790M mutation detection in patients with non-small cell lung cancer. MethodsStudy patients had EGFR-mutant tumours with disease progression on first/second generation EGFR tyrosine kinase inhibitors, and osimertinib treatment after T790M mutation detection. T790M status was tested by cobas assay using liquid biopsy, and only by ddPCR if an EGFR mutation was identified but T790M was negative. Clinical efficacy of osimertinib was compared between patients with T790M detected by cobas vs. only by ddPCR. A positive cut-off value for ddPCR was determined by assessing efficacy with osimertinib. Results61 patients had tumors with an acquired T790M mutation, 38 detected by cobas and an additional 23 only by ddPCR. The median progression-free survival (PFS) for the cobas- and ddPCR-positive groups was 9.5 and 7.8 months, respectively (p=0.43). For ddPCR, a fractional abundance (FA) of 0.1% was used as a cut-off value. The median PFS of patients with FA ≥0.1% and <0.1% was 8.3 and 4.6 months, respectively (p=0.08). FA ≥0.1% was independently associated with a longer PFS. ConclusionUsing ddPCR to follow up the cobas assay yielded more cases (38% of total) with a T790M mutation. A cut-off value of FA ≥0.1% identified patients who responded as well to osimertinib as those identified by cobas assay. This sequential approach should detect additional patients who might benefit from osimertinib treatment.

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

This study aimed to identify the impact of epidermal growth factor receptor (EGFR) T790M mutations on clinical characteristics and prognosis. 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 othermutations. 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 33months for patients with primary T790M mutations as compared to 48months 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 (17months vs. 9months, p = 0.009). 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.

Significance of micro-EGFR T790M mutations on EGFR-tyrosine kinase inhibitor efficacy in non-small cell lung cancer.

Small amounts of epidermal growth factor receptor (EGFR) T790M mutation (micro-T790M), which is detected using droplet digital PCR (ddPCR) but not conventional PCR, in formalin-fixed and paraffin-embedded (FFPE) samples have been investigated as a predictive factor for the efficacy of EGFR-tyrosine kinase inhibitors (TKIs). However, the predictive value of micro-T790M remains controversial, possibly owing to the failure to examine artificial T790M in FFPE specimens. Therefore, we examined the predictive value of micro-T790M in first-generation (1G), second-generation (2G), and third-generation (3G) EGFR-TKI efficacy using a new method to exclude FFPE-derived artificial mutations in our retrospective cohort. The primary objective was time to treatment failure (TTF) of 1G, 2G, and 3G EGFR-TKIs according to micro-T790M status. In total, 315 patients with EGFR-positive non-small cell lung cancer treated with 1G, 2G, and 3G EGFR-TKIs were included in this study. The proportion of patients positive formicro-T790M in the 1G, 2G, and 3G EGFR-TKI groups was 48.2%, 47.1%, and 47.6%, respectively. In the micro-T790M-positive group, the TTF was significantly longer in the 2G and 3G EGFR-TKI groups than in the 1G TKI group. No differences in the micro-T790M-negative group were observed. Micro-T790M status detected using ddPCR, eliminating false positives, may be a valuable predictor of EGFR-TKI efficacy.

A Phase II Study of Osimertinib in Patients with Advanced-Stage Non-Small Cell Lung Cancer following Prior Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor (EGFR TKI) Therapy with EGFR and T790M Mutations Detected in Plasma Circulating Tumour DNA (PLASMA Study).

Epidermal growth factor receptor (EGFR) T790M mutations drive resistance in 50% of patients with advanced non-small cell lung cancer (NSCLC) who progress on first/second generation (1G/2G) EGFR tyrosine kinase inhibitors (TKIs) and are sensitive to Osimertinib. Tissue sampling is the gold-standard modality of T790M testing, but it is invasive. We evaluated the efficacy of Osimertinib in patients with EGFR mutant NSCLC and T790M in circulating tumour DNA (ctDNA). PLASMA is a prospective, open-label, multicentre single-arm Phase II study. Patients with advanced NSCLC harbouring sensitizing EGFR and T790M mutations in plasma at progression from ≥one 1G/2G TKI were treated with 80 mg of Osimertinib daily until progression. The primary endpoint was the objective response rate (ORR); the secondary endpoints included progression-free survival (PFS), overall survival (OS), disease control rate (DCR) and toxicities. Plasma next-generation sequencing was performed to determine Osimertinib resistance mechanisms and assess serial ctDNA. A total of 110 patients from eight centres in five countries were enrolled from 2017 to 2019. The median follow-up duration was 2.64 (IQR 2.44-3.12) years. The ORR was 50.9% (95% CI 41.2-60.6) and the DCR was 84.5% (95% CI 76.4-90.7). Median PFS was 7.4 (95% CI 6.0-9.3) months; median OS was 1.63 (95% CI 1.35-2.16) years. Of all of the patients, 76% had treatment-related adverse events (TRAEs), most commonly paronychia (22.7%); 11% experienced ≥ Grade 3 TRAEs. The ctDNA baseline load and dynamics were prognostic. Osimertinib is active in NSCLC harbouring sensitizing EGFR and T790M mutations in ctDNA testing post 1G/2G TKIs.

Raddeanin A Improves the Therapeutic Effect of Osimertinib in NSCLC by Accelerating ROS/NLRP3-mediated Pyroptosis.

Osimertinib (Osm) is the preferred treatment for non-small cell lung cancer (NSCLC) patients with the epidermal growth factor receptor (EGFR) T790M mutation. Nevertheless, the resistance of NSCLC cells to Osm will eventually develop, which remains the biggest obstacle to treating such diseases. Raddeanin A (RA) exhibits a potent anti-tumor effect on various types of cancer cells. In this study, we aimed to investigate whether RA suppresses NSCLC growth and increases the therapeutic effect of Osm. The effects of RA on inhibiting NSCLC cell viability and proliferation were tested using cell counting kit 8 (CCK-8) and EdU assay. The roles of RA in improving the anti-tumor effect of Osm were tested with CCK-8 and colony formation assays. The roles of RA in regulating reactive oxygen species (ROS)/NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3)-mediated pyroptosis were assessed using quantitative real- time PCR (qRT-PCR) and western blotting analysis. RA treatment decreased A549 and H1975 cell viability in a dose- and time-dependent way. RA inhibited NSCLC cell proliferation and tumor growth in vivo. Mechanistically, RA induced ROS overgeneration and resulted in subsequent NLRP3-mediated pyroptosis. In particular, combination treatment with Osm and RA reduced cell viability and clonogenic growth capacity more efficiently than Osm mono treatment in A549 and H1975 cells. Combination treatment also promoted NLRP3-mediated pyroptosis more efficiently than Osm mono treatment. RA inhibited the NSCLC growth and increased the anti-tumor role of Osm in NSCLC by facilitating ROS/NLRP3-mediated pyroptosis. These results suggested that combination therapy with RA and Osm might be an effective strategy to treat Osm-resistant NSCLC.

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

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

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.

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. 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. 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 IdyllaTM detection method used in this study performed within the known sensitivity range of each detection method. 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.

Should We Perform Repeated Re-biopsy for the Detection of T790M Mutation?

Epidermal growth factor receptor (EGFR) T790M mutations have been detected in the second or third rebiopsy, even if the T790M mutation was not identified in the first rebiopsy. This meta-analysis investigated the EGFR T790M mutation detection rates and its additional advantages with repeated rebiopsies. We searched through the PubMed and EMBASE databases up to June 2022. Studies reporting rebiopsy to identify the EGFR T790M mutation in case of disease progression among patients with advanced non-small cell lung cancer and multiple rebiopsies were included. The quality of the included studies was checked using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. Eight studies meeting the eligibility criteria, reporting 1,031 EGFR mutation-positive patients were selected. The pooled EGFR T790M mutation detection rate of the first and repeated rebiopsies were 0.442 (95% confidence interval [CI], 0.411 to 0.473; I2=84%; p < 0.01) and 0.465 (95% CI, 0.400 to 0.530; I2=69%; p < 0.01), respectively. Overall, the pooled detection rate of EGFR T790M mutation was 0.545 (95% CI, 0.513 to 0.576), which increased by 10.3% with repeated rebiopsies. This meta-analysis identified that repeated rebiopsy increases the detection rate of EGFR T790M mutation by 10.3%, even if EGFR T790M mutation is not detected in the first rebiopsy. Our results indicate that the spatiotemporal T790M heterogeneity can be overcome with repeated rebiopsy.

Favorable Conditions for the Detection of EGFR T790M Mutation Using Plasma Sample in Patients with Non-Small-Cell Lung Cancer.

Detection of the epidermal growth factor receptor (EGFR) T790M mutation using plasma samples has been considered simple and non-invasive, but the relatively high false negative results lead to additional tissue sampling in some patients. Until now, the characteristics of patients who prefer liquid biopsy have not yet been established. To evaluate the favorable conditions for the detection of T790M mutations using plasma samples, a multicenter retrospective study was performed between May 2018 and December 2021. Patients whose T790M mutation was detected in a plasma sample were classified as the plasma positive group. Study subjects with a T790M mutation not detected in a plasma sample but only in a tissue sample were grouped as the plasma false negative group. Plasma positive and plasma false negative groups were found in 74 and 32 patients, respectively. As a result, 40% of patients with one or two metastatic organs at the time of re-biopsy had false negative plasma sample results, and 69% of patients with three or more metastatic organs at the time of re-biopsy had positive plasma results. In multivariate analysis, three or more metastatic organs at initial diagnosis were independently associated with the detection of a T790M mutation using plasma samples. Our results demonstrated that the detection rate of a T790M mutation using plasma samples was related to the tumor burden, particularly to the number of metastatic organs.

Initial Treatment of Aumolertinib in Combination with Bevacizumab for Advanced NSCLC with Primary EGFR T790M Mutation: A Report of Three Cases and Literature Review

With the development of sequencing technology, the detection rate of non-small cell lung cancer (NSCLC) with primary epidermal growth factor receptor (EGFR) T790M mutation is increasing. However, the first-line treatment for primary EGFR T790M-mutated NSCLC still lacks standard recommendations. Here, we reported three advanced NSCLC cases with EGFR-activating mutation and primary T790M mutation. The patients were initially treated with Aumolertinib combination with Bevacizumab; among which, one case was discontinued Bevacizumab due to bleeding risk after treatment for three months. Treatment was switched to Osimertinib after ten months of treatment. Another case switched to Osimertinib and discontinued Bevacizumab after thirteen months of treatment. The best effect response in all three cases was partial response (PR) after initial treatment. Two cases progressed after first-line treatment and progression-free survival (PFS) was eleven months and seven months respectively. The other one patient had persistent response after treatment, and the treatment duration has reached nineteen months. Two cases had multiple brain metastases before administration and the best response to intracranial lesions was PR. The intracranial PFS was fourteen months and not reached (16+ months), respectively. There were no new adverse events (AEs), and no AEs of grade three or above were reported. In addition, we summarized the research progress of Osimertinib in the treatment of NSCLC with primary EGFR T790M mutation. In conclusion, Aumolertinib combined with Bevacizumab in the treatment of advanced NSCLC with primary EGFR T790M mutation has a high objective response rate (ORR) and control ability of intracranial lesions, which can be used as one of the initial options for first-line advanced NSCLC with primary EGFR T790M mutation. .

Real-World Study of Osimertinib in Korean Patients with Epidermal Growth Factor Receptor T790M Mutation-Positive Non-Small Cell Lung Cancer.

Although osimertinib is the standard-of-care treatment of epidermal growth factor receptor (EGFR) T790M mutation-positive non-small cell lung cancer, real-world evidence on the efficacy of osimertinib is not enough to reflect the complexity of the entire course of treatment. Herein, we report on the use of osimertinib in patients with EGFR T790M mutation-positive non-small cell lung cancer who had previously received EGFR tyrosine kinase inhibitor (TKI) treatment in Korea. Patients with confirmed EGFR T790M after disease progression of prior EGFR-TKI were enrolled and administered osimertinib 80 mg daily. The primary effectiveness outcome was progression-free survival, with time-to-treatment discontinuation, treatment and adverse effects leading to treatment discontinuation, and overall survival being the secondary endpoints. A total of 558 individuals were enrolled, and 55.2% had investigator-assessed responses. The median progression-free survival was 14.2 months (95% confidence interval [CI], 13.0 to 16.4), and the median time-to-treatment discontinuation was 15.0 months (95% CI, 14.1 to 15.9). The median overall survival was 36.7 months (95% CI, 30.9 to not reached). The benefit with osimertinib was consistent regardless of the age, sex, smoking history, and primary EGFR mutation subtype. However, hepatic metastases at the time of diagnosis, the presence of plasma EGFR T790M, and the shorter duration of prior EGFR-TKI treatment were poor predictors of osimertinib treatment. Ten patients (1.8%), including three with pneumonitis, had to discontinue osimertinib due to severe adverse effects. Osimertinib demonstrated its clinical effectiveness and survival benefit for EGFR T790M mutation-positive in Korean patients with no new safety signals.

The exploration of three different treatment models of osimertinib plus antiangiogenic agents in non-small cell lung cancer: A real-world study.

BackgroundReal‐world application of osimertinib with antiangiogenic agents in non‐small cell lung cancer (NSCLC) is common, but the efficacy data are rarely reported.MethodsTo obtain an objective efficacy report of different real‐world treatment models of osimertinib and antiangiogenic agents.ResultsA total of 54 patients with NSCLC were enrolled into the study. Twelve (22.2%) who received a combination of antiangiogenic agents, when there was a trend of osimertinib resistance but did not reach imageology progressive disease (PD), were assigned to Group A, with a median overall survival (OS) and progression‐free survival (PFS) of 48.0 (95% CI, not reached) and 21.0 (95% CI: 16.7–25.3) months, respectively. Thirty (55.6%) who received a combination of antiangiogenic agents when there was imageology PD during treatment with osimertinib were assigned to Group B, with a median OS and PFS of 31.8 (95% CI: 26.6–37.1) and 9.2 (95% CI: 5.9–12.6) months, respectively. Twelve (22.2%) who received a combination of antiangiogenic agents at the initial treatment with osimertinib were assigned to Group C, with a median OS and PFS of 28.5 (95% CI: 15.2–41.8) and 15.3 (95% CI: 7.9–22.7) months, respectively. Patients in Group A achieved a significant prolonged median PFS (p < 0.001) compared with Groups B and C. Absence of epidermal growth factor receptor (EGFR) T790M mutations (p = 0.043; hazard ratio [HR] = 2.124, 95% CI: 1.023–4.413) and no previous antiangiogenic agent application (p = 0.012; HR = 0.362, 95% CI: 0.163–0.863) were the independent prognostic factors of OS.ConclusionThe well‐timed action to combine antiangiogenic agents was when there was a trend of osimertinib resistance. The absence of EGFR T790M mutations and previous use of antiangiogenic agents were poor prognostic factors.

Pretreatment HDL-C and ApoA1 are predictive biomarkers of progression-free survival in patients with EGFR mutated advanced non-small cell lung cancer treated with TKI.

BackgroundWe aimed to explore the correlation between blood lipids (high density lipoprotein cholesterol [HDL‐C] and apolipoprotein A1 [ApoA1]) and epidermal growth factor receptor (EGFR) T790M mutation, as well as its predictive role in clinical efficacy and progression‐free survial (PFS) in advanced non‐small cell lung cancer (NSCLC) patients treated with EGFR tyrosine kinase inhibitors (EGFR‐TKI).MethodsWe retrospectively collected information of 153 patients with advanced NSCLC harboring exon EGFR mutation and receiving EGFR‐TKI.ResultsThe best cutoff value for HDL‐C and ApoA1 was determined to be 1.15 and 1.14 mmol/l. The overall response rate (ORR) was 67.7% in the high HDL‐C group and 46.6% in the low HDL‐C group, respectively. The ORR of the high ApoA1 group showed a significant increase than that of the low ApoA1 group (68.1% vs. 38.5%). The mean ApoA1 level of the EGFR T790M mutation‐positive group was significantly higher than that of the EGFR T790M mutation‐negative group (1.13 g/l vs. 1.01 g/l). Patients with high ApoA1 levels were related to the EGFR T790M mutation (r = 0.324). (3) The median progression‐free survival (PFS) of the high HDL‐C group and low HDL‐C group were 13.00 months and 10.20 months. The median PFS of the high ApoA1 group and the low ApoA1 group were 12.10 and 10.00 months, respectively. Multivariate Cox stepwise regression model analysis demonstrated ECOG PS, pathological type and HDL‐C were confirmed as critical and independent predictors of PFS.ConclusionsPatients with EGFR T790M mutations often show higher ApoA1 levels. Peripheral serum HDL‐C and ApoA1 before treatment can be used as potential significant factors for predicting clinical efficacy and PFS in advanced NSCLC patients treated with EGFR‐TKI.

Assessment of Anti-tumor Efficacy of Osimertinib in Non-Small Cell Lung Cancer Patients by Liquid Biopsy Using Bronchoalveolar Lavage Fluid, Plasma, or Pleural Effusion.

PurposeThis study was to evaluate anti-tumor efficacy of osimertinib in patients positive for acquired epidermal growth factor receptor (EGFR) T790M mutation in liquid biopsy using plasma, bronchoalveolar lavage fluid (BALF) or bronchial washing fluid (BWF), and pleural effusion.Materials and MethodsAmong patients benefited from previous EGFR–tyrosine kinase inhibitor (TKI) treatment followed by treatment failure, patients in whom T790M mutations are detected in at least one of the samples including tumor tissues, BALF/BWF, plasma, and pleural effusion were enrolled. T790M mutation was detected by extracting cell free DNA from liquid biopsy samples, using PANA Mutyper. Objective response rate (ORR) and progression-free survival (PFS) with osimertinib treatment were evaluated.ResultsBetween January 2018 and December 2019, 63 patients were enrolled and received osimertinib. Mean age was 63 years, and 38 (60.3%) were female. Twenty-six patients had T790M mutation in both liquid and tissue samples (group A), 19 patients had only in tissue biopsy samples (group B), and 18 patients had T790M mutation only in liquid biopsy samples (group C). ORR in overall population was 63.5%, and was 61.5% in group A, 68.4% in group B, and 61.1% in group C, respectively. Median PFS in overall patients was 15.6 months (95% confidence interval, 10.7 to 24.2). There was no significant difference in ORR or PFS between groups.ConclusionOsimertinib showed favorable efficacy in lung cancer patients with acquired resistance to prior EGFR-TKI therapies, who screened positive for harboring T790M mutation detected from cell free DNA extracted from plasma, BALF/BWF, and pleural effusion.

Effect of almonertinib on the proliferation, invasion, and migration in non-small cell lung cancer cells.

Lung cancer is one of the most common malignant tumors in the world, and its lethality ranks the first among many malignant tumors. For non-small cell lung cancer (NSCLC) patients, due to the high mortality rate, the overall 5-year survival rate is less than 15%. When NSCLC undergoes local invasion, the 5-year survival rate is only 20%, and it is even lower when distant metastasis occurs up to 4%. Almonertinib is an innovative drug independently researched and developed by China with independent intellectual property rights. As an epidermal growth factor receptor tyrosine kinase inhibitor, almonertinib is mainly used for locally advanced or metastatic NSCLC patients with epidermal growth factor receptor (EGFR) T790M mutation. This study aims to investigate the effects of almonertinib on the proliferation, invasion and migration of NSCLC cells in vitro. NSCLC cells H1975 and PC-9 were cultured in vitro. The effects of almonertinib on the proliferation, apoptosis, invasion, and migration of H1975 and PC-9 cells were detected by CCK-8 assay, apoptotic assay and Transwell assay. The expression of invasion and migration related proteins was detected by Western blotting. The CCK-8 experiment showed that almonertinib inhibited the proliferation of H1975 and PC-9 cells in a time- and dose-dependent manner. The IC50 values in PC-9 cells at 24 and 48 h were 5.422 and 1.302 µmol/L, respectively. The IC50 values in H1975 cells at 24 and 48 h were 4.803 and 2.094 µmol/L, respectively. Almonertinib (1, 2, 4, 8 µmol/L)-treated PC-9 and H1975 cells for 24 h resulted in apoptosis rate at (8.82±3.22)%, (9.53±4.24)%, (13.62±3.69)%, (42.10±1.76)% and (9.81±0.90)%, (10.51±1.49)%, (15.34±3.50)%, (28.97±2.57)%, respectively. The transwell experiment showed that almonertinib inhibited the invasion and migration of H1975 and PC-9 cells. Western blotting showed that compared with the control group, the expression levels of MMP-9, MMP-2 and vimentin protein in PC-9 and H1975 cells in 1, 2 and 4 µmol/L almonertinib treatment group were significantly lower, and the expression level of E-cadherin protein was significantly higher (all P<0.05). The experimental results of nude mice showed that compared with the control group and the positive control ositinib (AZD9291) group, the tumor growth was significantly inhibited, the weight of nude mice, the tumor volume and the tumor mass were significantly reduced in the almonertinib treatment group (all P<0.05). Almonertinib can inhibit the proliferation, invasion, and migration of NSCLCH1975 and PC-9 cells in vitro and vivo, and promote the apoptosis of H1975 and PC-9 cells. The underlying mechanism may be related to the inhibition of tumor cell epithelial mesenchymal transformation and metalloproteinase expression.

Osimertinib Improves Overall Survival in Patients with Leptomeningeal Metastases Associated with EGFR-Mutated Non-Small-Cell Lung Cancer Regardless of Cerebrospinal Fluid T790M Mutational Status.

Osimertinib has demonstrated promising efficacy against leptomeningeal metastasis (LM) associated with T790M-positive non-small-cell lung cancer (NSCLC). However, the effect of cerebrospinal fluid's (CSF's) epidermal growth factor receptor (EGFR) T790M mutation on osimertinib efficacy remains unclear.Seventy-eight patients were studied with EGFR-mutated NSCLC and LM. Case data were collected and EGFR mutation status of circulating cell-free DNA from paired CSF, and plasma of 23 patients with LM was detected using droplet digital PCR. The median overall survival (mOS) was 8.08 months (95% CI: 6.07–10.09) in the study. Forty-four osimertinib-treated patients had an improved mOS of 13.15 (95% CI: 5.74–20.57) and a median progression-free survival (PFS) of 9.50 months (95% CI: 6.77–12.23) when compared with patients treated with first- or second-generation EGFR-TKI (mOS = 3.00 months (95% CI: 1.32–4.68) and median PFS = 1.50 months (95% CI: 0.00–3.14)). In the osimertinib group, mOS values for CSF with and without T790M mutation were 22.15 months (95% CI: 9.44–34.87) and 13.39 months (95% CI: 7.01–19.76), respectively, with no statistical differences. Regardless of the CSF T790M mutation status, osimertinib demonstrated significant efficacy against LM associated with NSCLC.

Survival benefit of osimertinib combination therapy in patients with T790M-positive non-small-cell lung cancer refractory to osimertinib treatment

ObjectivesOsimertinib is the main treatment choice for pretreated patients with advanced non-small cell lung cancer (NSCLC) harbouring epidermal growth factor receptor (EGFR) T790M mutations. However, the choice of subsequent therapy when progressive disease has developed after osimertinib treatment remains a major therapeutic challenge. This study evaluated the efficacy of osimertinib-based combination therapies in patients who developed progressive disease after treatment with osimertinib. Material and methodsWe enrolled NSCLC patients harbouring T790M mutations pretreated with first- or second-generation EGFR tyrosine-kinase inhibitors and were receiving osimertinib at two tertiary referral centres between August 2015 and July 2019, and the subsequent treatment efficacy was assessed. ResultsOsimertinib-based combination therapy yielded better overall survival (OS) than chemotherapy alone (not achieved vs. 7.8 months; hazard ratio, 0.39; 95 % confidence interval 0.17–0.89; P = 0.025) according to the Cox proportional hazards model adjusted for possible confounders. Synergism (combination index <1) between AZD9291 and chemotherapy and a higher proportion of apoptosis cells in combination treatment were also demonstrated in the T790M-positive PC9 cell line with acquired resistance to AZD9291. ConclusionOur data supported the hypothesis that osimertinib-based combination therapy is associated with improved OS among patients with clinical progression following the use of osimertinib. These findings warrant further validation in a randomised controlled study.