Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors Monotherapy Research Articles

Combination of EGFR-TKI and Chemotherapy Versus EGFR-TKI Monotherapy as Neoadjuvant Treatment of Stage III-N2 EGFR-Mutant Non-Small Cell Lung Cancer.

The efficacy of neoadjuvant treatment with epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) monotherapy in patients with stage III-N2 EGFR-mutant remains unsatisfactory. This study explored the potential benefits of combining first-generation EGFR-TKI with chemotherapy as a neoadjuvant treatment for patients with stage III-N2 EGFR-mutant non-small cell lung cancer (NSCLC). The medical records of patients with III-N2 EGFR-mutant NSCLC who received neoadjuvant therapy with EGFR-TKI at Shanghai Chest Hospital from October 2011 to October 2022 were retrospectively reviewed. Patients with stage III-N2 EGFR-mutant NSCLC who received first-generation TKI combined with chemotherapy as neoadjuvant treatment were included in the combination group, and those who received EGFR-TKI monotherapy were included in the monotherapy group. The study assessed the objective response rate (ORR) according to Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1, disease-free survival (DFS), overall survival (OS), downstaging rates of pathologic lymph nodes (from stage N2 to N1 or N0), major pathologic response (MPR) rate, pathological complete response (PCR) rate, and safety. A total of 74631 patients with EGFR-mutant NSCLC were screened, and 60 patients were included, 7 of whom did not undergo surgery after neoadjuvant targeted therapy. Of the remaining 53 patients, 15 received first-generation EGFR-TKI combined with chemotherapy as neoadjuvant treatment, and 38 received EGFR-TKI monotherapy. The median follow-up time was 44.12 months. The ORR was 50.0% (9/18) in the combination group and 40.5% (17/42) in the monotherapy group (P = .495). The MPR rate was 20.0% (3/15) and 10.5% (4/38) in the combination and monotherapy groups, respectively (P = .359). No patients achieved PCR in the combination group, while 3 (7.89%) attained PCR in the monotherapy group. The 2 groups did not differ in N2 downstaging rate (P = .459). The median DFS was not reached in the combination group, while it was 23.6 months (95% CI: 8.16-39.02) in the monotherapy group (P = .832). Adverse events observed were consistent with those commonly associated with the 2 treatments. Combination therapy with first-generation EGFR-TKI and chemotherapy could be considered a neoadjuvant treatment option for patients with stage III-N2 EGFR-mutant NSCLC, exhibiting acceptable toxicity. However, regarding short-term efficacy, combination therapy did not demonstrate superiority over EGFR-TKI monotherapy. Long-term follow-up is warranted for a more accurate assessment of the DFS and OS.

A retrospective study of the efficacy of combined EGFR‑TKI plus VEGF inhibitor/cytotoxic therapy vs. EGFR‑TKI monotherapy for PD‑L1‑positive EGFR‑mutant non‑small cell lung cancer: North Japan Lung Cancer Study Group 2202.

The present multicenter study was performed to compare the efficacy of epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) monotherapy with that of combined EGFR-TKI plus vascular endothelial growth factor receptor (VEGF) inhibitor/cytotoxic therapy in patients with programmed death-ligand 1 (PD-L1)-positive EGFR-mutant non-small cell lung cancer (NSCLC). Data from patients with PD-L1-positive EGFR-mutant NSCLC were collected from 12 institutes. Survival in patients treated with first- and second-generation EGFR-TKIs, osimertinib (third-generation EGFR-TKI), and combined EGFR-TKI plus VEGF inhibitor/cytotoxic therapy was analyzed by multiple regression analysis with adjustments for sex, performance status, EGFR mutation status, PD-L1 expression level, and the presence or absence of brain metastasis using a Cox proportional hazards model. Data from a total of 263 patients were analyzed, including 111 (42.2%) patients who had received monotherapy with a first- or second-generation EGFR-TKI, 132 (50.2%) patients who had received osimertinib monotherapy, and 20 (7.6%) patients who had received combined EGFR-TKI plus VEGF inhibitor/cytotoxic therapy (hereafter referred to as combined therapy). Multiple regression analysis using the Cox proportional hazards model showed that the hazard ratio (95% confidence interval) for progression-free survival was 0.73 (0.54-1.00) in the patients who had received osimertinib monotherapy and 0.47 (0.25-0.90) in patients who had received combined therapy. The hazard ratio for overall survival was 0.98 (0.65-1.48) in the patients who had received osimertinib monotherapy and 0.52 (0.21-1.31) in patients who had received combined therapy. In conclusion, combined therapy was associated with a significant reduction in the risk of progression compared with first- and second-generation EGFR-TKI monotherapy, and therefore, may be promising for the treatment of patients of NSCLC.

Pemetrexed induces ROS generation and cellular senescence by attenuating TS-mediated thymidylate metabolism to reverse gefitinib resistance in NSCLC.

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKI) are strongly recommended for non-small-cell lung cancer (NSCLC) patients harbouring active EGFR mutations, while drug resistance makes exploring resistance mechanisms and seeking effective therapeutic strategies urgent endeavours. Thymidylate synthetase (TYMS or TS) is a dominant enzyme in thymidylate nucleotide metabolism. In this study, we found a positive correlation between TS expression and overall survival (OS) and disease-free survival (DFS) in lung adenocarcinoma. The examination of gene sets from 140 NSCLC patients received EGFR-TKI therapy demonstrated a negative correlation between high TS expression and the efficacy of EGFR-TKI therapy. 24 tissue specimens from NSCLC patients exhibited upregulated TS mRNA expression in NSCLC patients resistant to gefitinib. The NSCLC cell PC9 and HCC827 sensitive to gefitinib and relatively resistant PC9/GR and HCC827/GR cells were used to demonstrate the knockdown of TS restored the sensitivity of resistant cells to gefitinib. Furthermore, pemetrexed effectively suppressed TS-mediated thymidylate metabolism and induced ROS generation, DNA damage and cellular senescence, thereby hampering cancer progression and restoring sensitivity to gefitinib. Our findings illuminate the potential mechanism of TS-triggered gefitinib resistance and indicate inhibition of TS by pemetrexed can potentiate the effect of gefitinib in NSCLC. Pemetrexed combined with gefitinib has potent anti-progression potential in gefitinib-resistant NSCLC. This study suggests that NSCLC patients with both high TS expression and EGFR-driving mutations might benefit more from a combination strategy of EGFR-TKI and pemetrexed-based chemotherapy than EGFR-TKI monotherapy, which has profound clinical implications and therapeutic value.

Efficacy and safety of epidermal growth factor receptor tyrosine kinase inhibitors combined with chemotherapy as first-line treatment for epidermal growth factor receptor-mutant advanced non-small cell lung cancer

Objective: To observe the clinical efficacy and safety of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) combined with chemotherapy as first-line treatment for EGFR mutant advanced non-small cell lung cancer (NSCLC). Methods: It was a retrospective, single-arm real-world study and a total of 39 patients with stage ⅢB to Ⅳ EGFR mutant NSCLC diagnosed in Cancer Hospital of Chinese Academy of Medical Sciences from July 2018 to December 2020 were collected. There were 16 males and 23 females, the age ranged from 25 to 73 years, with a median age of 53 years. All patients received EGFR-TKIs synchronously combined with pemetrexed and platinum-containing chemotherapy for 4-6 cycles as first-line treatment, followed by EGFR-TKI monotherapy with or without pemetrexed maintenance therapy. The objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS) and adverse reactions were evaluated. Median follow-up time was 18.6 months (95%CI: 16.2-21.0 months). The Kaplan-Meier method was used for survival analysis. Results: The ORR was 61.5% (24/39), the DCR was 94.9% (37/39) and the median PFS was 16.4 months (95%CI: 12.1-20.7 months). The main adverse reactions were liver function injury (59.0%, 23/39), myelosuppression (43.6%, 17/39), skin reaction (25.6%, 10/39), gastrointestinal reaction (17.9%, 7/39), fatigue (12.8%, 5/39) and kidney injury (5.1%, 2/39). Most of the patients had grade 1-2 adverse reactions, and the rate of grade 3 adverse events were 12.8%(5/39), which were effectively alleviated after symptomatic support treatment, no grade 4 serious adverse events occurred. Conclusion: EGFR-TKIs synchronously combined with chemotherapy followed by EGFR-TKI monotherapy with or without pemetrexed maintenance therapy has a certain therapeutic effect and fairly good safety, which can prolong PFS in patients with EGFR mutated advanced NSCLC.

Challenges of EGFR-TKIs in NSCLC and the potential role of herbs and active compounds: From mechanism to clinical practice.

Epidermal growth factor receptor (EGFR) mutations are the most common oncogenic driver in non-small cell lung cancer (NSCLC). Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) are widely used in the treatment of lung cancer, especially in the first-line treatment of advanced NSCLC, and EGFR-TKIs monotherapy has achieved better efficacy and tolerability compared with standard chemotherapy. However, acquired resistance to EGFR-TKIs and associated adverse events pose a significant obstacle to targeted lung cancer therapy. Therefore, there is an urgent need to seek effective interventions to overcome these limitations. Natural medicines have shown potential therapeutic advantages in reversing acquired resistance to EGFR-TKIs and reducing adverse events, bringing new options and directions for EGFR-TKIs combination therapy. In this paper, we systematically demonstrated the resistance mechanism of EGFR-TKIs, the clinical strategy of each generation of EGFR-TKIs in the synergistic treatment of NSCLC, the treatment-related adverse events of EGFR-TKIs, and the potential role of traditional Chinese medicine in overcoming the resistance and adverse reactions of EGFR-TKIs. Herbs and active compounds have the potential to act synergistically through multiple pathways and multiple mechanisms of overall regulation, combined with targeted therapy, and are expected to be an innovative model for NSCLC treatment.

Adjuvant EGFR-TKI therapy in resected EGFR-mutation positive non-small cell lung cancer: A real-world study.

Although several clinical studies have laid the foundation for the adjuvant application of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), some questions remain unresolved. This real-world study aimed to address questions such as the effect of adjuvant chemotherapy prior to adjuvant EGFR-TKI therapy on survival outcomes, and the duration of adjuvant EGFR-TKI therapy, etc. Between October 2005 and October 2020, 227 consecutive patients with non-small cell lung cancer (NSCLC) who underwent complete pulmonary resections were included in this retrospective study. Patients received postoperative adjuvant chemotherapy followed by EGFR-TKI or adjuvant EGFR-TKI monotherapy. The disease-free survival (DFS) and overall survival (OS) were evaluated. Of the total 227 patients, 55 (24.2%) patients underwent 3-4 cycles of chemotherapy prior to receiving adjuvant EGFR-TKI therapy. The 5-year DFS rate was 67.8%, while the 5-year OS rate was 76.4%. The stages were significantly associated with both DFS (P<0.001) and OS (P<0.001), while no significant differences were observed in the DFS (P=0.093) and OS (P=0.399) between the adjuvant chemotherapy followed by EGFR-TKI and adjuvant EGFR-TKI monotherapy groups. A longer duration of EGFR-TKI therapy was associated with better DFS (P<0.001) and OS (P<0.001) benefit. Additionally, pTNM stage and duration of EGFR-TKI therapy were considered independent prognostic factors for long-term survival (All P<0.05). This study supports the use of EGFR-TKI as a postoperative adjuvant treatment for patients with stage II-IIIA EGFR-mutation positive NSCLC. Additionally, patients with stage I who had pathological risk factors were also suitable for receiving adjuvant EGFR-TKI therapy. Postoperative EGFR-TKI based, chemotherapy-free adjuvant regimen may be a potential therapeutic option for patients with EGFR-mutation positive NSCLC.

Treatment outcomes of EGFR-TKI with or without locoregional brain therapy in advanced EGFR-mutant non-small cell lung cancer patients with brain metastases.

This study aimed to evaluate the treatment outcomes of epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) therapy alone or in combination with locoregional brain therapy for advanced EGFR-mutant non-small cell lung cancer (NSCLC) patients with brain metastases. A retrospective study involving 72 advanced EGFR-mutant NSCLC patients with brain metastases at the Vietnam National Cancer Hospital were conducted. Patients were divided into 2 groups: EGFR-TKI (erlotinib) monotherapy and EGFR-TKI combined with locoregional therapy (γ knife surgery - GKS or whole-brain radiation therapy). Evaluation criteria included clinical and laboratory characteristics, central nervous system (CNS) progression time, progression-free survival (PFS), overall survival (OS), T790M mutation rate, and adverse events. Epidermal growth factor receptor tyrosine kinase inhibitor monotherapy patients had better performance status (PS), fewer CNS symptoms, and significantly fewer brain metastases (p < 0.05). Median PFS and OS were 11 and 25 months, respectively, in both groups. Patients with PS 0-1 had longer median PFS (15 months) than those with PS 2 (7 months) (p = 0.039). Exon 19 deletion patients in both groups had longer median OS (26 months) than those with L858R exon 21 (15 months) (p = 0.023). Patients with T790M mutation who received osimertinib after progression had longer median OS (41 months vs. 23 months, p = 0.0001). Median time to CNS progression was 13.9 months (48 patients). Longer time to CNS progression correlated with longer OS (R2 = 0.89). Epidermal growth factor receptor tyrosine kinase inhibitor therapy, with or without locoregional therapy, is effective for advanced EGFR-mutant NSCLC patients with brain metastases. Exon 19 deletion patients had better prognosis.

Correlations of switch/sucrose nonfermentable complex mutations with clinical outcomes in advanced non-small cell lung cancer.

The switch/sucrose nonfermentable complex mutations (SWI/SNF-mut) are common in non-small cell lung cancer (NSCLC). However, the association of SWI/SNF-mut with the clinical outcomes of immune checkpoint inhibitors (ICIs), particularly of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), has not been established. We retrospectively collected data of patients at Cancer Hospital Chinese Academy of Medical Sciences. Patients with advanced NSCLC who received programmed cell death protein-1 or programmed cell death ligand 1 (PD-[L]1) inhibitors were included in cohort 1 and those with EGFR mutations (EGFR-mutant) received EGFR-TKIs monotherapy were included in cohort 2. Two reported Memorial Sloan-Kettering Cancer Center (MSKCC) cohorts received immunotherapy alone used as the validation for cohort 1. We analyzed the relationship between SWI/SNF alterations and clinical outcomes in each cohort. In total, 1162 patients were included, of which 230 patients (19.8%) were identified as SWI/SNF-mut with the most common genetic alterations being ARID1A (33.4%) and SMARCA4 (28.3%). In cohort 1 (n=146), patients with co-mutations of SWI/SNF and Kirsten rat sarcoma oncogene (KRAS) (SWI/SNFmutKRASmut, n=18) had significantly prolonged progression-free survival (PFS) (8.6m vs. 1.9 m; hazard ratio [HR],0.31; 95% confidence intervals [CI], 0.11-0.83; p=0.032) to PD-(L)1 inhibitors monotherapy, which was consistent with the MSKCC cohorts (not reach [NR] vs. 6.3 m; HR,0.36, 95% CI, 0.15-0.82; p=0.016). In cohort 2 (n=205), ARID1A-mut (n=16) was associated with improved PFS after EGFR-TKIs (20.6m vs. 11.2 m; HR,0.47, 95% CI, 0.27-0.94; p=0.023). In advanced NSCLC, patients with SWI/SNFmutKRASmut seem to benefit more from ICIs. Furthermore, ARID1A-mut may provide a protective effect to EGFR-TKIs in EGFR-mutant patients. However, this is a retrospective single-institution analysis that requires further validation by large prospective studies.

Research Progress of Angiogenesis Inhibitors Plus EGFR-TKI in EGFR-mutated Advanced Non-small Cell Lung Cancer

肺癌是最常见、致死率最高的肿瘤性疾病之一，使用表皮生长因子受体酪氨酸激酶抑制剂（epidermal growth factor receptor tyrosine kinase inhibitor, EGRF-TKI）已经成为EGFR突变晚期非小细胞肺癌（non-small cell lung cancer, NSCLC）的标准治疗方式。然而耐药事件的发生往往是不可避免的。EGFR-TKI联合抗血管生成药物（angiogenesis inhibitor）是目前一种正在探索的延缓耐药事件发生的治疗方案，被称为“A+T治疗”。多项临床试验已经证明A+T治疗相较于单药可以延长患者的无进展生存期（progression free survival, PFS）。然而，基于不同EGFR-TKI的A+T治疗相对于EGFR-TKI单药治疗所带来的获益程度、安全性和探索前景仍不明确。因此，我们回顾了第一、二、三代EGFR-TKI联合抗血管生成药物治疗的相关文献，总结了A+T治疗模式的增益机制、获益程度、安全性以及最佳的目标人群。

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.

Efficacy and acquired resistance of EGFR-TKI combined with chemotherapy as first-line treatment for Chinese patients with advanced non-small cell lung cancer in a real-world setting

BackgroundTo compare the benefits and explore the cause of acquired resistance of epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) and its combination with chemotherapy in advanced non-small-cell lung cancer (NSCLC) patients harboring EGFR mutation in a real-life setting.MethodsThis retrospective analysis included 117 advanced NSCLC patients with EGFR mutation who underwent next-generation sequencing (NGS) prior to treatment. The combination group included 50 patients who received the regimen of EGFR-TKI combined with chemotherapy, while the EGFR-TKI monotherapy group included 67 patients treated with TKI only. The primary endpoint of this study was progression-free survival (PFS); the secondary endpoints were overall survival (OS), response rate, and toxicity.ResultsThe median PFS was significantly longer in the combination group than in the EGFR-TKI monotherapy group (19.00 months [95% CI, 14.67–23.33] vs. 11.70 months [95% CI, 10.81–12.59], p < 0.001). Subgroup analysis showed a similar trend of results. The median OS was not reached in the combination group and was 38.50 (95% CI, 35.30–41.70) months in the EGFR-TKI monotherapy group (p = 0.586). Patients in the combination group were more likely to experience adverse events, most of which showed the severity of grade 1 or 2. T790M mutation remains the main reason for acquired resistance, and the frequency of T790M mutation was similar between the two groups (p = 0.898).ConclusionsCompared with EGFR-TKI monotherapy, EGFR-TKI combined with chemotherapy significantly improved PFS in advanced NSCLC patients with EGFR mutation, with acceptable toxicity.

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.

Gustave Roussy Immune Score Is a Prognostic Factor for Chemotherapy-Naive Pulmonary Adenocarcinoma With Wild-Type Epidermal Growth Factor Receptor.

BackgroundThe Gustave Roussy Immune Score (GRIm-Score) was developed based on the Royal Marsden Hospital (RMH) prognostic score for the purpose of a better patient selection for immunotherapy phase I trials. This scoring system is simply calculated by neutrophil-to-lymphocyte ratio, lactate dehydrogenase (LDH), and serum albumin concentration. The aim of our study was to determine whether GRIm-Score is a practically useful prognostic biomarker for advanced non-small cell lung cancer (NSCLC) patients treated with cytotoxic chemotherapy or epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI).MethodsThis retrospective and single institutional study collected 185 adenocarcinomas without active EGFR mutation, 115 squamous cell carcinomas treated with first-line cytotoxic chemotherapy, and 140 NSCLCs with mutant EGFR treated with first- or second-generation EGFR-TKI monotherapy. These treatments were initiated between July 2007 and March 2018 at our hospital. We compared overall survival (OS) and progression-free survival (PFS) between high and low GRIm-Score groups. Using multivariate Cox proportional hazard analyses, we also found prognostic factors of survival times.ResultsThe OS and PFS of low GRIm-Score group were significantly longer than those of high-score group in wild-type EGFR adenocarcinoma (low vs. high; median OS, 18.4 vs. 5.1 months, P < 0.01, and median PFS, 5.8 vs. 3.7 months, P = 0.01) and EGFR-mutant NSCLC (median OS, 38.9 vs. 10.4 months, P < 0.01, and median PFS, 15.9 vs. 5.0 months, P < 0.01). Subsequent multivariate analyses detected high GRIm-Score in wild-type EGFR adenocarcinoma as a poor prognostic factor of OS (hazard ratio (HR) 2.20, 95% CI 1.47 - 3.31, P < 0.01), and in the EGFR-mutant NSCLC as a poor prognostic factor of PFS (HR 1.89, 95% CI 1.00 - 3.55, P = 0.049).ConclusionsHigh GRIm-Score was an independent prognostic biomarker of OS of first-line cytotoxic chemotherapy for wild-type EGFR adenocarcinoma and of PFS of first- or second-generation EGFR-TKI for EGFR-mutant NSCLC. Therefore, GRIm-Score is not only a specific selection marker for experimental immunotherapy trials, but may also be a promising and useful pretreatment prognostic maker for specific NSCLC subsets in the real-world practice.

Combination of EGFR-TKIs with chemotherapy versus chemotherapy or EGFR-TKIs alone in advanced NSCLC patients with EGFR mutation.

PurposeBoth epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) and chemotherapy are widely applied for the treatment of advanced non-small-cell lung cancer (NSCLC) with EGFR mutations, and the combination of EGFR-TKIs and chemotherapy has been used for advanced NSCLC patients; however, little is known about the efficacy of the direct comparison among them.Patients and methodsThe demographic and clinical characteristics of 92 patients harboring advanced NSCLC with EGFR mutation were retrospectively reviewed. We evaluated the effects of EGFR-TKIs, chemotherapy, and EGFR-TKIs plus chemotherapy on advanced NSCLC patients with EGFR mutations, and the efficacy of combination of chemotherapy and EGFR-TKIs vs chemotherapy or EGFR-TKIs alone in advanced NSCLC patients was evaluated.ResultsThe statistical results showed that the intercalated combination of EGFR-TKIs plus chemotherapy significantly improved progression-free survival (PFS; HR, 1.76; 95% CI 1.03–3.01; P=0.036; median, 20.5 vs 16 months) compared with EGFR-TKI monotherapy, but no difference in overall survival (OS) was observed between these two groups (HR, 1.52; 95% CI 0.81–2.83; P=0.19; median, 36 vs 29 months). However, patients who received the combination of chemotherapy and EGFR-TKIs had longer PFS (HR, 2.78; 95% CI 1.57–4.93; P<0.0001; median, 20.5 vs 12 months) as well as OS (HR, 2.86; 95% CI 1.56–5.27; P=0.001; median, 36 vs 18 months) than those who received chemotherapy alone. Toxicities were mild among the three treatment groups. Rash and diarrhea were common adverse events (AEs) in the EGFR-TKI group, anemia and nausea in the chemotherapy group, and anemia and diarrhea in the combination group.ConclusionThis study demonstrated that the combination of chemotherapy with EGFR-TKIs as first-line treatment has a significant effect on PFS in patients with advanced NSCLC whose tumors harbor activating EGFR mutations. The combination treatment had more toxicity, but was clinically manageable.

MA27.03 Multi-Omic Characterization of TKI-Treated Drug-Tolerant Cell Population in an EGFR-Mutated NSCLC Primary-Derived Xenograft

Sixty to eighty percent of advanced stage lung adenocarcinoma patients with epidermal growth factor receptor (EGFR) mutated tumors respond to first generation EGFR tyrosine kinase inhibitors (TKIs). However, cure is not yet achievable with any EGFR TKI monotherapy, as patients eventually progress due to acquired resistance. In vitro evidence suggests that minor populations of epigenetically modified drug tolerant cells (DTCs) may be important for tumor cells surviving TKI. We hypothesize that molecularly characterizing DTCs in vivo and comparing them to the untreated tumor in a patient-derived xenograft (PDX) model may delineate mechanisms of tolerance that closely mimic those occurring in patients. DTCs were produced via chronic exposure to erlotinib in a lung adenocarcinoma PDX harbouring an exon 19 deletion. Histological, genomic, transcriptomic (including single-cell RNA-seq), and epigenetic characterizations were performed on DTCs and compared to untreated baseline (BL) tumors. Compared to BL, DTCs exhibit decreased levels of proliferation (Ki67 by immunohistochemistry (IHC) and increased expression of senescence/quiescence (p21) and anti-apoptosis (BCL-XL) immunohistochemistry (IHC) markers, while maintaining EGFR pathway signaling (pEGFR, pAKT, pERK, pS6 IHC). Whole exome-sequencing provides evidence that DTCs likely do not represent mutationally distinct subclones from the bulk tumor. Instead, DTCs exhibit a number of differentially expressed genes compared to BL tumors that are involved in cell cycle arrest, senescence/quiescence, differentiation, vesicles, and inflammation. Genes with epigenetic differences (chromatin openness and/or promoter methylation) are involved in similar cellular processes. A minor (<2%) subpopulation of transcriptomically-defined DTC-like cells in the BL tumors are very similar to the DTCs, supporting the hypothesis that DTCs may exist prior to treatment. A number of transcription regulators are found to have differential gene expression and epigenetic regulation as well as DNA-binding motifs found in regions of chromatin uniquely open in DTCs or baseline tumors. These transcription regulators are involved in cell maintenance, proliferation, and differentiation, and may play key roles in promoting DTC phenotype. In this specific EGFR mutant PDX model sensitive to first generation TKIs, DTC-like cells are found in the BL untreated tumors, and its resultant phenotype after exposure to TKI appears to be involved in cell cycle, differentiation, senescence/quiescence, proliferation and maintenance. PDX models may provide insights into therapeutic strategies to target DTCs, and further improve the survival of EGFR-mutated NSCLC patients.

Continuous EGFR tyrosine kinase inhibitor treatment with or without chemotherapy beyond gradual progression in non-small cell lung cancer patients.

BackgroundSeveral clinical studies have demonstrated that continuous administration of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) could provide additional survival benefit for advanced non-small cell lung cancer (NSCLC) patients who had benefited from prior EGFR TKI therapy. However, whether EGFR TKI combined with chemotherapy could further prolong survival in patients with gradual progression is still unclear. The present study was conducted to evaluate the clinical outcome of continuous EGFR TKI treatment in combination with chemotherapy (combination group) versus continuous EGFR TKI treatment only (monotherapy group) in such a clinical setting.MethodsWe designed a cohort study to collect all chart data of NSCLC patients treated with EGFR TKI in our institution from February 2012 to December 2015 retrospectively and followed up the clinical outcome of EGFR TKI monotherapy or therapy in combination with chemotherapy until April 2017 prospectively. All eligible patients had to meet the criteria of gradual progression. The time interval of progression-free survival 1 (PFS1, gradual progression or death) to PFS2 (off-EGFR TKI progression), and overall survival (OS) between the above 2 groups were used in survival analysis.ResultsIn all, 50 patients were included in our study. Patients’ baseline characteristics were well balanced. Exon 19 deletion mutations and L858R point mutations were detected in 16 and 8 patients, respectively. Twenty, 22, and 8 patients were treated with EGFR TKI in the first, second, and third line setting, respectively. The time interval from PFS1 to PFS2 was 92 and 37 days (monotherapy vs combination), respectively (hazard ratio [HR] =1.16, 95% confidence interval [CI]: 0.61–2.21, P=0.652). The median OS in the monotherapy group and combination group was 696 and 799 days, respectively (HR =0.74, 95% CI: 0.33–1.71, P=0.501). There were no statistical differences between the 2 groups in terms of the time interval from PFS1 to PFS2 and OS.ConclusionOur results suggested that compared with EGFR TKI monotherapy, its combination with chemotherapy beyond gradual progression may not confer a significant survival benefit to NSCLC patients. Further prospective studies are warranted to reinforce the results of the study.

Tyrosine kinase inhibitor combination therapy in first-line treatment of non-small-cell lung cancer: systematic review and network meta-analysis.

IntroductionThe introduction of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) has improved the outlook for patients with advanced non-small-cell lung cancer (NSCLC) with EGFR+ mutations. However, most patients develop resistance, with the result that median progression-free survival (PFS) iŝ12 months. Combining EGFR-TKIs with other agents, such as bevacizumab, is a promising approach to prolonging remission. This systematic review and network meta-analysis (NMA) were undertaken to assess available evidence regarding the benefits of first-line combination therapy involving EGFR-TKIs in patients with advanced NSCLC.MethodsLiterature searches were performed using relevant search terms. Study-level pseudo-individual patient-level data (IPD) were recreated from digitized Kaplan–Meier curve data, using a published algorithm. Study IPD were analyzed using both the proportional hazards and the acceleration failure time (AFT) survival models, and it was concluded that the AFT model was most appropriate. An NMA was performed based on acceleration factors (AFs) using a Bayesian framework to compare EGFR-TKIs and chemotherapy.ResultsNine randomized controlled trials were identified that provided data for EGFR-TKI therapy in patients with EGFR+ tumors. These included studies of afatinib (n=3), erlotinib (n=3), erlotinib plus bevacizumab (n=1) and gefitinib (n=2). Erlotinib plus bevacizumab produced the greatest increase in PFS compared with chemotherapy, with 1/AF being 0.24 (95% credible interval [CrI] 0.17, 0.34). This combination also produced greater increases in PFS compared with EGFR-TKI monotherapy: 1/AF versus afatinib, 0.51 (95% CrI 0.35, 0.73); versus erlotinib, 0.53 (95% CrI 0.39, 0.72) and versus gefitinib, 0.46 (95% CrI 0.32, 0.66). All three EGFR-TKI monotherapies prolonged PFS compared with chemotherapy; estimates of treatment effect ranged from 1/AF 0.53 (95% CrI 0.48, 0.60) for gefitinib to 1/AF 0.46 (95% CrI 0.40, 0.53) for erlotinib. There was no evidence for differences between EGFR-TKI monotherapies, as all 95% CrIs included the null value.ConclusionAlthough data for erlotinib plus bevacizumab came from a single Phase 2 study, the results of the NMA suggest that adding bevacizumab to erlotinib may be a promising approach to improving the outcomes achieved with EGFR-TKI monotherapy in patients with advanced EGFR+ NSCLC.

P2.05-030 WBRT Prior EGFR TKIs is Effective Treatment Option for NSCLC Patients with CNS Metastases Harboring EGFR Mutation: Topic: Multimodality Treatment

Central nervous system (CNS) metastases are considered as a common cause of morbidity and mortality in advanced non-small-cell lung cancer (NSCLC). It is estimated that 20–40% of NSCLC develop CNS metastases during their disease course. Sensitivity of chemotherapy is limited in CNS metastases of NSCLC, because of restrict transit function of blood-brain barrier. The main treatment options based on whole brain radiation therapy (WBRT), stereotactic radiosurgery, neurosurgery or combination of them. Median overall survival (mOS) achieved in NSCLC with CNS metastases treated with irradiation methods is 6.5-7.5 months. Introduction of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) – gefitinib, erlotinib, afatinib – improved the treatment possibilities in selected group of NSCLC patients harboring EGFR gene mutations. Also CNS metastatic lesions of NSCLC showed sensitivity to EGFR-TKIs (mOS to 15-17 months). Moreover, concurrent EGFR TKIs and WBRT may be used synergistic because potentially improve survival and delays intracranial progression. The main aim of the study was evaluation weather implementation of WBRT prior EGFR TKIs in NSCLC patients with CNS metastases might influence on their survival in comparison to patients without CNS metastases treated with EGFR TKIs monotherapy. The studied group included 178 NSCLC patients harboring EGFR gene mutation. 160 (110 female, 50 male; median age 67 years) patients with primary NSCLC received EGFR TKIs in first or second line of treatment. 18 patients (16 female, 2 male; median age 69 years), who had diagnosed CNS metastases, received WBRT prior administration of EGFR TKIs. The treatment response was showed in both studied group. We did not observe a significant difference in survival in both studied groups. The progression free survival (PFS) in patients with primary NSCLC treated with EGFR TKIs and in patients with CNS lesions treated with WBRT prior EGFR TKIs was 10 vs. 9 months (p=0.785; HR=1.07; 95% CI=0,618-1.866), respectively. Also mOS did not show significance discrepancies in both studied group (26 vs. 32 months, respectively; p=0.32; HR=0.639; 95% CI=0.301-1.356). Implementation of WBRT prior TKIs did not lead to additional neurotoxicity. The following study showed that combination of WBRT prior TKIs in NSCLC patients with CNS metastases achieves similar benefit like treatment of primary NSCLC (without CNS metastases) with EGFR TKIs monotherapy. Based on overall data, patients with CNS metastases achieved better response rate when EGFR TKIs are administrated prior WBRT. It may be caused by EGFR TKIs feature which possess CNS penetrability for radiation.

The safety and efficacy of osimertinib for the treatment of EGFR T790M mutation positive non-small-cell lung cancer

ABSTRACTFirst- and second-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are the evidence-based first-line treatment for metastatic non-small-cell lung cancers (NSCLCs) that harbor sensitizing EGFR mutations (i.e. exon 19 deletions or L858R). However, acquired resistance to EGFR TKI monotherapy occurs invariably within a median time frame of one year. The most common form of biological resistance is through the selection of tumor clones harboring the EGFR T790M mutation, present in >50% of repeat biopsies. The presence of the EGFR T790M mutation negates the inhibitory activity of gefitinib, erlotinib, and afatinib. A novel class of third-generation EGFR TKIs has been identified by probing a series of covalent pyrimidine EGFR inhibitors that bind to amino-acid residue C797 of EGFR and preferentially inhibit mutant forms of EGFR versus the wild-type receptor. We review the rapid clinical development and approval of the third-generation EGFR TKI osimertinib for treatment of NSCLCs with EGFR-T790M.

The Efficacy of Synchronous Combination of Chemotherapy and EGFR TKIs for the First-Line Treatment of NSCLC: A Systematic Analysis.

BackgroundThe combination of chemotherapy and epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) currently has become the hotspot issue in the treatment of non-small lung cancer (NSCLC). This systematic review was conducted to compare the efficacy and safety of the synchronous combination of these two treatments with EGFR TKIs or chemotherapy alone in advanced NSCLC.MethodsEMBASE, PubMed, the Central Registry of Controlled Trials in the Cochrane Library (CENTRAL), Chinese biomedical literature database (CNKI) and meeting summaries were searched. The Phase II/III randomized controlled trials were selected by which patients with advanced NSCLC were randomized to receive a combination of EGFR TKIs and chemotherapy by synchronous mode vs. EGFR TKIs or chemotherapy alone.ResultsA total of six randomized controlled trials (RCTs) including 4675 patients were enrolled in the systematic review. The meta-analysis demonstrated that the synchronous combination group of chemotherapy and EGFR TKIs did not reach satisfactory results; there was no significant difference in overall survival (OS), time to progression (TTP) and objective response rate (ORR), compared with monotherapy (OS: HR = 1.05, 95%CI = 0.98–1.12; TTP: HR = 0.94, 95%CI = 0.89–1.00; ORR: RR = 1.07, 95%CI = 0.98–1.17), and no significant difference in OS and progression-free survival (PFS), compared with EGFR TKIs alone (OS: HR = 1.10, 95% CI = 0.83–1.46; PFS: HR = 0.86, 95% CI = 0.67–1.10). The patients who received synchronous combined therapy presented with increased incidences of grade 3/4 anemia (RR = 1.40, 95% CI = 1.10–1.79) and rash (RR = 7.43, 95% CI = 4.56–12.09), compared with chemotherapy, grade 3/4 anemia (RR = 6.71, 95% CI = 1.25–35.93) and fatigue (RR = 9.60, 95% CI = 2.28–40.86) compared with EGFR TKI monotherapy.ConclusionsThe synchronous combination of chemotherapy and TKIs is not superior to chemotherapy or EGFR TKIs alone for the first-line treatment of NSCLC.