Reduced chemotherapy sensitivity in EGFR-mutant lung cancer patient with frontline EGFR tyrosine kinase inhibitor

Osimertinib Rechallenge With Bevacizumab vs. Chemotherapy Plus Bevacizumab in EGFR-Mutant NSCLC Patients With Osimertinib Resistance

At present, treatment options for osimertinib resistance are very limited. Dual inhibition of the vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) significantly improved the progression-free survival (PFS) of advanced EGFR-mutant non–small cell lung cancer (NSCLC). After EGFR-tyrosine kinase inhibitor (TKI) resistance, EGFR-TKI continuation combined with VEGF inhibitors still had clinical benefits. It is unclear whether the addition of bevacizumab after osimertinib progresses will prolong the duration of the osimertinib benefit. We screened 1289 patients with NSCLC and finally included 96 patients to evaluate osimertinib combined with bevacizumab (osi + bev) versus chemotherapy combined with bevacizumab (che + bev) for patients with acquired resistance to osimertinib. The overall response rate (ORR) for osi + bev and chem + bev was 15.8% (6 of 38) and 20.7% (12 of 58), respectively. The median PFS for osi + bev and che + bev was 7.0 and 4.9 months (HR 0.415 95%CI: 0.252–0.687 p = 0.001). The median OS for osi + bev and che + bev was 12.6 and 7.1 months (HR 0.430 95%CI: 0.266–0.696 p = 0.001). Multivariate analyses showed that no brain metastases and osi + bev treatment after osimertinib resistance correlated with longer PFS (p = 0.044, p = 0.001), while the median PFS of osimertinib less than 6 months (p = 0.021) had a detrimental effect on sequent treatment. Only osi + bev treatment was identified as an independent predictor of OS (p = 0.001). The most common adverse events (AEs) of grade ≥3 were hypertension (13.2%) and diarrhea (10.5%) in the osi + bevacizumab group. Neutropenia (24.1%) and thrombocytopenia (19%) were the most common grade ≥3 AEs in the che + bev group. The overall incidence of serious AEs (grade ≥3) was significantly higher in the chemotherapy plus bevacizumab group. Our study has shown the superiority of osi + bev compared to che + bev after the failure of osimertinib, making it a preferred option for patients with acquired resistance to osimertinib.

Clinical factors associated with treatment toxicity of pemetrexed plus platinum in elderly patients with non-small cell lung cancer

BACKGROUND

This study was to explore the clinical factors associated with treatment toxicities of pemetrexed plus platinum in elderly patients with non-small cell lung cancer (NSCLC).

METHODS

Chemo-naive patients aged ≥ 70 with advanced NSCLC treated with pemetrexed plus platinum were included. Medical records were reviewed and clinical data, including age, gender, smoking status, comorbidities, EGFR mutation status, chemotherapy regimens, previous use of epidermal growth factor receptor-tyrosine kinase inhibitors, treatment-related hematologic, renal, and hepatic toxicities, and treatment responses, were analyzed. Comorbidity conditions were evaluated by using the Simplified Comorbidity Score (SCS) and Charlson Comorbidity Index Score (CCIS).

RESULTS

A total of 144 patients were included. In the univariate analysis, patients with SCS >9 (p = 0.006) and cigarette smoking (p = 0.028) were associated with a significantly higher rate of grade 3/4 neutropenia than their counterpart. Carboplatin use was associated with a higher rate of grade 3/4 thrombocytopenia than cisplatin use (p = 0.028). In the multivariate analysis, SCS >9 was associated with a significantly higher risk of anemia of any grade (odds ratio [OR]: 2.72, 95% confidence interval [CI]: 1.09-6.77). Carboplatin use was associated a higher risk of any grade (OR: 4.61, 95% CI: 1.07-19.90) and grade 3/4 thrombocytopenia (OR: 7.37, 95% CI: 1.36-39.92). No clinical factors were found to be associated with hepatic and renal toxicities.

CONCLUSION

High SCS and carboplatin use were associated with hematological toxicities with pemetrexed plus platinum use in elderly patients with NSCLC.

Sequential Administration of EGFR-TKI and Pemetrexed Achieved a Long Duration of Response in Advanced NSCLC Patients with EGFR-mutant Tumours

Objectives: The optimal combination of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) and chemotherapy has helped to improve therapeutic effects in non-small-cell lung cancer (NSCLC). This study aimed to explore the progression free survival (PFS) of patients after sequential administration of TKI and pemetrexed chemotherapy. Methods: This study retrospectively screened treatment-naive advanced NSCLC patients harbouring EGFR mutations who were prescribed a TKI and salvaged with pemetrexed chemotherapy or vice versa. The total, initial and salvage PFS were collected. Results: The total PFS including both the initial and salvage PFS was 18.0 mon (95% CI: 14.1–21.9 mon), which was not influenced by the sequence of administration (TKI first: 18.0 mon, 95% CI: 15.8–20.2 mon, pemetrexed first: 16.1 mon, 95% CI: 9.1–23.1 mon, HR 0.92, P=0.748). A longer PFS was achieved for TKI over chemotherapy in both the initial (10.6 and 5.9 mon, HR 2.62, P=0.001) and salvage therapy (12.0 and 6.0 mon, HR 1.29, P=0.001). TKI remained effective either before (10.6 mon) or after (12.0 mon) chemotherapy (HR 0.96, P=0.853). The same trend was observed for chemotherapy (5.9 and 6.0 mon for initial and salvage therapy, respectively, HR 0.82, P=0.417). Conclusions: The sequential administration of TKI and pemetrexed chemotherapy achieved a long PFS and was a suitable treatment for advanced NSCLC.

Efficacy of pemetrexed-based regimens in advanced non-small cell lung cancer patients with activating epidermal growth factor receptor mutations after tyrosine kinase inhibitor failure: a systematic review

Pemetrexed-based chemotherapy regimens (pem regimens) are the standard first-line treatment option in patients with non-squamous non-small cell lung cancer (NSCLC). The objective of this systematic review was to assess the efficacy of pemetrexed in the context of epidermal growth factor receptor (EGFR) mutation-positive NSCLC following the failure of EGFR-tyrosine kinase inhibitor (TKI) treatment. We searched biomedical literature databases (PubMed, EMBASE, and the Cochrane library) and conference proceedings for studies evaluating the efficacy of pemetrexed monotherapy or pemetrexed combined with platinum or any other chemotherapeutic agent in EGFR-mutation-positive NSCLC after EGFR-TKI failure. We extracted data of primary outcomes of interest (progression-free survival [PFS], overall survival [OS], and overall response rate [ORR]). The weighted median PFS, OS, and ORR were then calculated. Of 83 potentially relevant studies, eight (three randomized studies and five retrospective studies) were identified (involving 1,193 patients) and included in this systematic review, with 640 patients receiving pem regimens. The weighted median PFS, median OS, and ORR for patients treated with pem regimens were 5.09 months, 15.91 months, and 30.19%, respectively. Our systematic review results showed a favorable efficacy profile of pem regimens in NSCLC patients with EGFR mutation after EGFR-TKI failure.

Comparison of outcomes of tyrosine kinase inhibitor in first- or second-line therapy for advanced non-small-cell lung cancer patients with sensitive EGFR mutations

Direct comparisons between the use of first- and second-line EGFR tyrosine kinase inhibitor (TKI) in patients with sensitive EGFR mutations are limited. A total of 264 advanced non-small-cell lung cancer (NSCLC) patients with sensitive mutations received EGFR TKI therapy as the first-line therapy, and a total of 187 patients received TKI as the second-line therapy at Shanghai Chest Hospital. First-line EGFR TKI therapy [12.9 months, 95% confidence interval (CI), 10.7-15.2] provided longer progression-free survival (PFS) than did second-line EGFR TKI therapy (9.0 months, 95% CI, 7.7-10.2) [hazard ratio (HR): 0.78, P = 0.034]. The objective response rate (ORR) of first-, and second-line TKI therapy were 67.8% (159/233) and 55.6% (94/169), respectively (P = 0.001). The overall survival (OS) for patients (n = 141) receiving first-line TKI followed by second-line chemotherapy were longer than those for patients (n = 187) receiving first-line chemotherapy followed by second-line TKI (HR: 0.69, P = 0.02).Compared with second-line TKI, first-line therapy achieved a significant and longer PFS, and higher ORR in the sensitive EGFR mutated NSCLC patients. The therapeutic strategy of using TKI followed by chemotherapy achieved longer OS than that using chemotherapy followed by TKI.

Oncogenic driver mutations, treatment, and EGFR-TKI resistance in a Caucasian population with non-small cell lung cancer: survival in clinical practice

Introduction

Oncogenic driver mutations activating EGFR, ALK, or BRAF in NSCLC predict sensitivity to specific tyrosine-kinase inhibitors (TKIs). We provide data on prevalence, treatment and survival of driver-mutation positive NSCLC in a predominantly Caucasian population in routine clinical practice.

Patients and Methods

NSCLC patients diagnosed from 2006-2015 with an EGFR-test result were included (n=265). Testing for EGFR, ALK, or BRAF was performed if specific TKI therapy was considered. Case-control analyses of overall survival (OS) comparing driver-mutation positive and negative patients were performed.

Results

44 sensitizing EGFR mutations (17%), 8 ALK translocations (7%, n=111) and 3 BRAF mutations (8%, n=39) were detected in adenocarcinoma or adenosquamous carcinoma. We did not find mutations in tumors without an adenocarcinoma-component. More than 90% of inoperable driver-mutation positive patients received TKI-therapy. Case-control analysis revealed improved OS of driver-mutation positive patients (39.6 vs. 19.4 months, HR 0.51). OS was improved in stage IV patients but not in stage I-III patients.

OS of EGFR-TKI treated patients was similar for 1^st and 2^nd-line EGFR-TKI treatment. Patients not treated with EGFR-TKI had no benefit in OS. Re-biopsies obtained at progression revealed an EGFR-T790M mutation in 73% (n=11). These patients responded to the 3^rd-generation EGFR-TKI osimertinib.

Discussion

Testing guided by predictive clinical parameters resulted in twice as high rates of mutation-positive patients than expected, and TKI treatment resulted in a strong long-term OS advantage.

Conclusion

Testing for driver mutations is feasible in routine clinical practice, and identifies patients who benefit from TKI-therapy. OS compares favorably with OS in clinical studies.

Bevacizumab plus chemotherapy for patients with advanced pulmonary adenocarcinoma harboring EGFR mutations

Purpose

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) and bevacizumab plus chemotherapy were effective for EGFR-mutant patients. However, the appropriated treatment orders remained controvertible. We investigated the efficacy of treatment orders between bevacizumab plus chemotherapy and EGFR-TKIs for EGFR-mutant patients with advanced pulmonary adenocarcinoma.

Patients and methods

This study involved 40 EGFR-mutant patients with advanced pulmonary adenocarcinoma who were treated with bevacizumab plus carboplatin and paclitaxel (Bev + CP) and EGFR-TKIs in different treatment orders or gemcitabine plus cisplatin (GP) in first-line setting. Seventeen patients were treated with Bev + CP and 10 cases with GP in first-line treatment. Thirteen patients received EGFR-TKIs after first-line Bev + CP regimen, while 13 patients were treated with first-line EGFR-TKIs. Progression-free survival (PFS), the response rate (ORR) and overall survival (OS) were evaluated.

Results

Median PFS of Bev + CP treatment was significantly longer in first-line than non-first-line settings (11.7 vs. 5.6 months, P = 0.003). Median OS was 37.8 months for EGFR-mutant patients with first-line Bev + CP followed by second-line EGFR-TKIs and 31.0 months for those with first-line EGFR-TKIs and non-first-line Bev + CP, respectively (P = 0.509). Median PFS was 11.7 (95% CI 10.6–12.8) months for Bev + CP group and 4.7 (95% CI 4.4–5.0) months for GP group with the hazard ratio of 0.17 (P = 0.001). ORR was 70.6 and 50.0% in the two groups, respectively (P = 0.415). However, there was no significant difference in median OS (33.7 vs 27.8 months, P = 0.293).

Conclusions

First-line Bev + CP followed by EGFR-TKIs might possibly provide favorable prognosis for EGFR-mutant patients. Bev + CP regimen significantly prolonged PFS in first-line than non-first-line settings. These findings warrant further investigations.

Electronic supplementary material

The online version of this article (doi:10.1007/s12094-017-1714-2) contains supplementary material, which is available to authorized users.

Clinical Implications of the T790M Mutation in Disease Characteristics and Treatment Response in Patients With Epidermal Growth Factor Receptor (EGFR)-Mutated Non-Small-Cell Lung Cancer (NSCLC)

BACKGROUND

The secondary T790M mutation accounts for more than 50% of acquired tyrosine kinase inhibitor (TKI) resistance in patients with EGFR-mutated non-small-cell lung cancer (NSCLC). Recent reports suggest this resistance mutation may be more common among patients with longer progression-free survival (PFS) on first-line TKI therapy, but much is still unknown.

MATERIALS AND METHODS

Our group collected medical records from patients who underwent a biopsy for T790M mutation testing while screening for clinical trials involving the drug rociletinib (CO-1686), a T790M mutation-specific TKI. Medical records were retrospectively analyzed for demographic data, PFS, and best response to previous therapies.

RESULTS

Our patient cohort included 69 T790M⁺ patients and 28 T790M^- patients. Patients who later developed a T790M mutation had a longer PFS on first-line TKI therapy (12.0 vs. 9.0 months, P = .021), but overall response rate (ORR) was the same (75.0% vs. 81.0%, P = .76). There was no difference in PFS on TKI rechallenge (4.0 vs. 3.0 months, P = .94), although there was a trend toward higher ORR in T790M⁺ patients (22.2% vs. 0%, P = .12). T790M⁺ patients had a longer PFS on initial chemotherapy treatment (5.0 vs. 4.0 months, P = .025) and a trend toward higher ORR (40.0% vs. 21.4%, P = .31).

CONCLUSION

Our study confirms that tumors expressing T790M have a more indolent progression of disease compared with their T790M^- counterparts when treated with both first-line TKI and cytotoxic chemotherapy.

Factors associated with efficacy of first-generation epidermal growth factor receptor tyrosine kinase inhibitors in non-small-cell lung cancer

The finding of epidermal growth factor receptor tyrosine kinase inhibitors, which reflects a classical process of translational research, is a critical milestone for non-small-cell lung cancer treatment. Currently, epidermal growth factor receptor tyrosine kinase inhibitors are recommended as first-line therapy for non-small-cell lung cancer patients harboring epidermal growth factor receptor-sensitive mutations. The status of epidermal growth factor receptor mutation is widely acknowledged as superior to other clinical factors, such as smoking, gender, and histological types for predicting the response to epidermal growth factor receptor tyrosine kinase inhibitors. However, recent studies have shown that the efficacy might differ in patients with the same epidermal growth factor receptor-sensitive mutations, highlighting the need to investigate the putative factors related to the efficacy of epidermal growth factor receptor tyrosine kinase inhibitors. This article reviews the factors associated with clinical efficacy of first-generation epidermal growth factor receptor tyrosine kinase inhibitors, such as gefitinib and erlotinib, and analyzes their potential implications with respect to clinical application. In addition, new findings related to clinical practice with respect to epidermal growth factor receptor tyrosine kinase inhibitors efficacy were summarized in this article.

Unravelling signal escape through maintained EGFR activation in advanced non-small cell lung cancer (NSCLC): new treatment options

The discovery of activating epidermal growth factor receptor (EGFR) mutations has opened up a new era in the development of more effective treatments for patients with non-small cell lung cancer (NSCLC). However, patients with EGFR-activating mutated NSCLC treated with EGFR tyrosine kinase inhibitors (TKIs) ultimately develop acquired resistance (AR). Among known cases of patients with AR, 70% of the mechanisms involved in the development of AR to EGFR TKI have been identified and may be categorised as either secondary EGFR mutations such as the T790M mutation, activation of bypass track signalling pathways such as MET amplification, or histologic transformation. EGFR-mutant NSCLC tumours maintain oncogenic addiction to the EGFR pathway beyond progression with EGFR TKI. Clinical strategies that can be implemented in daily clinical practice to potentially overcome this resistance and prolong the outcome in this subgroup of patients are presented.

Tyrosine Kinase Receptor Landscape in Lung Cancer: Therapeutical Implications

Lung cancer is a heterogeneous disease responsible for the most cases of cancer-related deaths. The majority of patients are clinically diagnosed at advanced stages, with a poor survival rate. For this reason, the identification of oncodrivers and novel biomarkers is decisive for the future clinical management of this pathology. The rise of high throughput technologies popularly referred to as “omics” has accelerated the discovery of new biomarkers and drivers for this pathology. Within them, tyrosine kinase receptors (TKRs) have proven to be of importance as diagnostic, prognostic, and predictive tools and, due to their molecular nature, as therapeutic targets. Along this review, the role of TKRs in the different lung cancer histologies, research on improvement of anti-TKR therapy, and the current approaches to manage anti-TKR resistance will be discussed.

Efficacy and safety of rechallenge treatment with gefitinib in patients with advanced non-small cell lung cancer

OBJECTIVES

Although patients with advanced non-small cell lung cancer (NSCLC) and an activating epidermal growth factor receptor (EGFR) mutation benefit from the use of EGFR-tyrosine kinase inhibitors (TKI), most of them progress within 12 months from treatment start due to acquired resistance. In clinical practice, many physicians frequently offer these patients retreatment with EGFR-TKIs after a chemotherapy break, based on small or retrospective studies.

MATERIALS AND METHODS

A phase II trial was conducted in patients with stage III/IV NSCLC, to assess the efficacy, safety and impact on quality of life (QoL) and disease-related symptoms of gefitinib rechallenge. Eligible patients had initially responded to first-line gefitinib and progressed after second-line chemotherapy.

RESULTS

Of 61 enrolled patients, 73.8% were female, 100% had EGFR-mutated adenocarcinoma and 67.2% were never-smokers. Thirty-two (52.5%) patients obtained a clinical benefit, with 3 (4.9%) achieving a partial response and 29 (47.5%) having stable disease. Median progression-free survival was 2.8 months, overall survival 10.2 months and duration of gefitinib treatment 3.6 months. The most common all grade-adverse events were diarrhea (27.6%), nausea and/or vomiting (20.3%), rash (14.7%) and dyspnea (10.3%); no new toxicities were apparent.

CONCLUSION

Findings from this study indicate that gefitinib rechallenge offers modest benefit and may be taken into consideration only for patients for whom no other treatment option exists.

Overall survival benefits of first-line EGFR tyrosine kinase inhibitors in EGFR-mutated non-small-cell lung cancers: a systematic review and meta-analysis

BACKGROUND

Accumulating data shows that exon 19 deletions and L858R, both activating epidermal growth factor receptor mutations in non-small-cell lung cancers (NSCLCs), are just two different entities in terms of prognosis and treatment response to tyrosine kinase inhibitors (TKIs).

METHODS

A systematic review and meta-analysis of randomized controlled trials comparing TKIs with conventional chemotherapy was performed. Eight trials of 1498 patients and five trials of 1279 patients with either exon 19 deletions or L858R were included in the meta-analysis.

RESULTS

TKI treatment demonstrated progression-free survival benefit in patients with exon 19 deletions (hazard ratio (HR): 0.27, 95% confidence interval (CI): 0.21-0.35) and L858R (HR: 0.45, 95% CI: 0.35-0.58). Patients with exon 19 deletions had significant overall survival (OS) benefit under TKI treatment (HR: 0.72, 95% CI: 0.60-0.88). Subgroup analyses showed that irreversible TKIs, but not reversible TKIs, had statistically significant OS benefit in these patients (irreversible TKIs, HR: 0.59, 95% CI: 0.47-0.73; reversible TKIs, HR: 0.84, 95% CI: 0.69-1.02). Patients with L858R demonstrated no OS benefit under first-line TKI use (HR: 1.15, 95% CI: 0.95-1.39).

CONCLUSIONS

In patients with advanced NSCLC harbouring exon 19 deletions, TKIs are associated with better OS compared with conventional chemotherapy. Future clinical trials should take exon 19 deletions and L858R as distinct disease entities and evaluate the treatment efficacy separately.