A Randomized Phase II Study Comparing Nivolumab With Carboplatin-Pemetrexed for Patients With EGFR Mutation-Positive Nonsquamous Non-Small-Cell Lung Cancer Who Acquire Resistance to Tyrosine Kinase Inhibitors Not Due to a Secondary T790M Mutation: Rationale and Protocol Design for the WJOG8515L Study

Treatment of advanced non-small cell lung cancer with driver mutations: current applications and future directions

With the improved understanding of driver mutations in non-small cell lung cancer (NSCLC), expanding the targeted therapeutic options improved the survival and safety. However, responses to these agents are commonly temporary and incomplete. Moreover, even patients with the same oncogenic driver gene can respond diversely to the same agent. Furthermore, the therapeutic role of immune-checkpoint inhibitors (ICIs) in oncogene-driven NSCLC remains unclear. Therefore, this review aimed to classify the management of NSCLC with driver mutations based on the gene subtype, concomitant mutation, and dynamic alternation. Then, we provide an overview of the resistant mechanism of target therapy occurring in targeted alternations ("target-dependent resistance") and in the parallel and downstream pathways ("target-independent resistance"). Thirdly, we discuss the effectiveness of ICIs for NSCLC with driver mutations and the combined therapeutic approaches that might reverse the immunosuppressive tumor immune microenvironment. Finally, we listed the emerging treatment strategies for the new oncogenic alternations, and proposed the perspective of NSCLC with driver mutations. This review will guide clinicians to design tailored treatments for NSCLC with driver mutations.

Immunotherapy for EGFR-mutant advanced non-small-cell lung cancer: Current status, possible mechanisms and application prospects

Immune checkpoint inhibitors (ICIs) are effective against advanced and even perioperative non-small-cell lung cancer (NSCLC) and result in durable clinical benefit, regardless of programmed death ligand-1 (PD-L1) expression status in cancer. Existing clinical evidence shows that the effect of immunotherapy in patients with EGFR-mutant NSCLC after the development of tyrosine kinase inhibitor (TKI) resistance is not satisfactory. However, compared with monotherapy, ICIs combined with chemotherapy can improve the efficacy. Encouragingly, compared with that of patients with sensitive mutations, the progression-free survival of patients with rare mutations who were treated with ICIs was increased. Adequately maximizing the efficacy of ICIs in EGFR-mutant NSCLC patients is worth exploring. In this review, we described preclinical and clinical studies of ICIs or combined therapy for EGFR-mutant NSCLC. We further focused on EGFR mutations and the cancer immune response, with particular attention given to the role of EGFR activation in the cancer-immunity cycle. The mechanisms for the natural resistance to ICIs were explored to identify corresponding countermeasures that made more EGFR-mutant NSCLC patients benefit from ICIs.

Treatment Strategies for Non-Small Cell Lung Cancer Harboring Common and Uncommon EGFR Mutations: Drug Sensitivity Based on Exon Classification, and Structure-Function Analysis

The identification of epidermal growth factor receptor (EGFR) mutations and development of EGFR tyrosine kinase inhibitors (EGFR-TKIs) have dramatically improved the prognosis of advanced EGFR-mutated non-small cell lung cancer (NSCLC), setting a landmark in precision oncology. Exon 19 deletions and exon 21 L858R substitutions, which comprise the majority of common EGFR mutations, are predictors of good sensitivity to EGFR-TKIs. However, not all cancers harboring EGFR mutations are sensitive to EGFR-TKIs. Most patients harboring uncommon EGFR mutations demonstrate a poorer clinical response than those harboring common EGFR mutations. For example, cancers harboring exon 20 insertions, which represent approximately 4-12% of EGFR mutations, are generally insensitive to first- and second-generation EGFR-TKIs. Although understanding the biology of uncommon EGFR mutations is essential for developing treatment strategies, there is little clinical data because of their rarity. Moreover, clarifying the acquired resistance of EGFR-mutated NSCLC may lead to more precise treatments. Sequencing and structure-based analyses of EGFRmutated NSCLC have revealed resistance mechanisms and drug sensitivity. In this review, we discuss the strategies in development for treating NSCLC harboring common and uncommon EGFR mutations. We will also focus on EGFR-TKI sensitivity in patients harboring EGFR mutations based on the structural features.

A Randomized Phase II Study Comparing Nivolumab with Carboplatin-Pemetrexed for EGFR-Mutated NSCLC with Resistance to EGFR Tyrosine Kinase Inhibitors (WJOG8515L)

PURPOSE

Although the efficacy of programmed cell death-1 (PD-1) blockade is generally poor for non-small cell lung cancer (NSCLC) with activating mutations of the epidermal growth factor receptor (EGFR) gene, EGFR tyrosine kinase inhibitors (TKIs) may improve the tumor immune microenvironment. We performed a randomized study to assess whether nivolumab improves outcome compared with chemotherapy in such patients previously treated with EGFR-TKIs.

PATIENTS AND METHODS

Patients with EGFR-mutated NSCLC who acquired EGFR-TKI resistance not due to a secondary T790M mutation of EGFR were randomized 1:1 to nivolumab (n = 52) or carboplatin-pemetrexed (n = 50). The primary endpoint was progression-free survival (PFS).

RESULTS

Median PFS and 1-year PFS probability were 1.7 months and 9.6% for nivolumab versus 5.6 months and 14.0% for carboplatin-pemetrexed [log-rank P < 001; hazard ratio (HR) of 1.92, with a 60% confidence interval (CI) of 1.61-2.29]. Overall survival was 20.7 and 19.9 months [HR, 0.88 (95% CI, 0.53-1.47)], and response rate was 9.6% and 36.0% for nivolumab and carboplatin-pemetrexed, respectively. No subgroup including patients with a high tumor mutation burden showed a substantially longer PFS with nivolumab than with carboplatin-pemetrexed. The T-cell-inflamed gene expression profile score (0.11 vs. -0.17, P = 0.036) and expression of genes related to cytotoxic T lymphocytes or their recruitment were higher in tumors that showed a benefit from nivolumab.

CONCLUSIONS

Nivolumab did not confer a longer PFS compared with carboplatin-pemetrexed in the study patients. Gene expression profiling identified some cases with a favorable tumor immune microenvironment that was associated with nivolumab efficacy.

Development of EGFR TKIs and Options to Manage Resistance of Third-Generation EGFR TKI Osimertinib: Conventional Ways and Immune Checkpoint Inhibitors

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) have been first-line therapy in the treatment of non-small cell lung cancer (NSCLC) harboring EGFR sensitive mutations. Progression inevitably happens after 10–14 months of first- or second-generation EGFR TKIs treatment for acquired resistance. Owing to the successful identification of EGFR T790M, third-generation EGFR TKIs such as osimertinib were developed to target such resistance mutation. Nowadays, osimertinib has shown its efficacy both in first-line and second-line after resistance to previous generations of TKI treatment of EGFR-mutant NSCLC. However, drug resistance also emerges on third-generation EGFR TKIs. Multiple mechanisms of acquired resistance have been identified, and some novel strategies were reported to overcome third-generation TKI resistance. Immune checkpoint inhibitors (ICIs) have dramatically changed the prognosis of selected patients. For patients with EGFR-addicted metastatic NSCLC, ICIs have also revealed a potential role. In this review, we will take stock of mechanisms of acquired resistance to third-generation TKIs and discuss current challenges and future perspectives in clinical practice.

Immunotherapy in advanced non-small-cell lung cancer with EGFR mutations

EGFR-tyrosine kinase inhibitors (EGFR-TKIs) had been regarded as the front-line treatment for advanced non-small-cell lung cancer (NSCLC) patients with EGFR mutations. However, resistance to EGFR-TKIs is inevitable, it remains a major challenge. Immune checkpoint inhibitors (ICIs) had shown superior clinical efficacy in many types of solid tumors, while it exhibited impaired overall efficacy in NSCLC with EGFR mutations. In this review, we will perform a meta-analysis to assess the relationship between the programmed death ligand 1 (PD-L1) expression and clinical benefit of EGFR-TKIs. We also overview the immunotherapy in advanced NSCLC patients with EGFR mutations to investigate the potential biomarkers predicting the ICIs efficiency, and the subgroups that could benefit from ICIs treatment.

Does Pemetrexed Work in Targetable, Nonsquamous Non-Small-Cell Lung Cancer? A Narrative Review

Simple Summary

The chemotherapy agent pemetrexed is currently considered in combination with other therapies for the treatment of advanced nonsquamous non-small-cell lung cancer (NSCLC) in patients negative for gene mutations/rearrangements. The aim of this review was to highlight data from clinical studies with pemetrexed in patients with advanced nonsquamous NSCLC positive for gene mutations/rearrangements. The results of the review suggest that pemetrexed could be a treatment option in patients with advanced nonsquamous NSCLC positive for certain gene mutations/rearrangements.

Abstract

Pemetrexed is currently mainly considered for the treatment of advanced nonsquamous non-small-cell lung cancer (NSCLC) negative for gene mutations/rearrangements (wild-type disease (WTD)). This narrative review aimed to highlight the role of pemetrexed in the treatment of onco-driven nonsquamous advanced NSCLC by reviewing published clinical studies. For epidermal growth factor receptor (EGFR) mutations, patient survival following first-line pemetrexed–platinum was longer than for WTD. Later-line pemetrexed-based treatment after tyrosine kinase inhibitor (TKI) failure provided greater benefits than non-pemetrexed regimens. First- and later-line pemetrexed-based therapy also provided survival benefits in patients with anaplastic lymphoma kinase (ALK) or ROS proto-oncogene 1 (ROS1) rearrangements. In patients with rearranged during transfection (RET) proto-oncogene rearrangements, survival with pemetrexed was similar to that in ALK- and ROS1-positive patients and longer than that in patients with Kirsten rat sarcoma (KRAS) virus proto-oncogene mutations or WTD, although the available studies were limited. For Erb-b2 receptor tyrosine kinase 2 (ERRB2) mutations, first-line pemetrexed showed outcomes similar to those for EGFR and KRAS alterations. Data on pemetrexed in patients with KRAS mutations or MNNG HOS-transforming (MET) expression were limited. Pemetrexed could be an option for first- and second-line treatment for TKI failure in nonsquamous advanced NSCLC with select targetable driver mutations.

Application of immune checkpoint inhibitors in EGFR-mutant non-small-cell lung cancer: from bed to bench

Targeted therapies are efficient in the context of oncogenic driver mutations. Epidermal growth factor receptor (EGFR)-mutant lung cancers represent a distinct subset of non-small-cell lung cancer (NSCLC) with marked sensitivity to EGFR tyrosine kinase inhibitors (TKIs). Despite the high response rate to EGFR TKIs in EGFR-mutant lung cancer, resistance and tumor recurrence are unavoidable. Therapeutic options are restricted in patients after exhaustion of targeted therapies. Immune checkpoint inhibitors (ICIs) represent a novel therapeutic option for advanced NSCLC with significant overall survival benefit in registration trials. No superiority in terms of long-term survival was observed in the EGFR mutation subgroup when ICIs were given as monotherapy in second-line treatment in earlier studies. Thus, the appropriate application of ICIs to patients harboring EGFR mutations remains an important field of ongoing research. Here, we discuss different immune checkpoint blockade strategies, including ICIs alone and in combination with TKIs, chemotherapy, radiation, and antiangiogenic agents in EGFR-mutant NSCLC as first-line and subsequent treatments. We also summarize the evidence concerning the heterogeneous molecular features and immune signatures of EGFR mutations and their associations with ICI therapy outcomes. This study was performed to improve our understanding of the optimal mode of immune-based treatment approaches in EGFR-mutant NSCLC.

Serum Homocysteine and Vitamin B12 as Biomarkers for Haematological Toxicity in Lung Adenocarcinoma Treated With Pemetrexed

Background Serum homocysteine (Hcy) and vitamin B12 (VitB12) were investigated as serological markers for the prediction of pemetrexed induced haematological toxicity in patients with adenocarcinoma of the lung.

Material and Methods A total of 35 lung adenocarcinoma patients who received pemetrexed chemotherapy as first-line treatment were included in the present study. The patients received pemetrexed 500 mg/m2 once every three weeks until disease progression. Serum Hcy and VitB12 levels were analysed prior to chemotherapy. Haematological toxicities (leucopenia, neutropenia and thrombocytopenia) were graded for each cycle of chemotherapy. Serum Hcy and VitB12 concentrations were compared between grades 0-1 and 2-4 haematological toxicity groups.

Results A total of 151 chemotherapy cycles were administered to 35 lung adenocarcinoma patients. However, the serum Hcy and VitB12 concentration were only examined and recorded in 61 out of the 151 chemotherapy cycles. For the 61 cycles, grade 2-4 leucopenia, neutropenia and thrombocytopenia were observed in 21, 20 and 10 cases, respectively. Serum Hcy levels were 14.91±4.67 μg/ml, 15.50±4.35 μg/ml and 16.04±4.90 μg/ml for grade 2-4 leucopenia, neutropenia and thrombocytopenia, respectively, which were significantly higher than those of grade 0-1 groups (p<0.05). However, serum VitB12 were not statistically different between grade 0-1 and 2-4 haematological toxicity groups (p>0.05). The area under the ROC curve (AUC) were 0.73 (0.58-0.88), 0.80 (0.66-0.94), 0.75 (0.57-0.93) for serum Hcy and 0.65 (0.50-0.79), 0.64 (0.49-0.78), 0.68 (0.49-0.87) for serum VitB12 as predictive biomarkers of grade 2-4 leucopenia, neutropenia and thrombocytopenia, respectively.

Conclusion Pre-chemotherapy serum Hcy appeared to correlate with haematological toxicity and may be a useful biomarker for predicting severity of pemetrexed induced haematological toxicity.

Epidermal growth factor induces STAT1 expression to exacerbate the IFNr-mediated PD-L1 axis in epidermal growth factor receptor-positive cancers

The epidermal growth factor (EGF) receptor (EGFR) overexpressed in many cancers, including lung and head and neck cancers, and is involved in cancer cell progression and survival. PD-L1, increases in tumor cells to evade and inhibit CD8+ T cells, is a clinical immunotherapeutic target. This study investigated the molecular mechanism of EGF on regulating PD-L1 in EGFR-positive cancers and determined potential agents to reduce PD-L1 expression. RNA sequencing (RNAseq) and bioinformatics analysis were performed to determine potential driver genes that regulate PD-L1 in tumor cells-derived tumorspheres which mimicking cancer stem cells. Then, the specific inhibitors targeting EGFR were applied to reduce the expression of PD-L1 in vitro and in vivo. We validated that EGF could induce PD-L1 expression in the selected EGFR-positive cancers. RNAseq results revealed that STAT1 increased as a driver gene in KOSC-3-derived tumorspheres; these data were analyzed using PANTHER followed by NetworkAnalyst. The blockade of EGFR by afatinib resulted in decreased STAT1 and IRF-1 levels, both are transcriptional factors of PD-L1, and disabled the IFNr-STAT1-mediated PD-L1 axis in vitro and in vivo. Moreover, STAT1 knockdown significantly reduced EGF-mediated PD-L1 expression, and ruxolitinib, a JAK1/JAK2 inhibitor, significantly inhibited STAT1 phosphorylation to reduce the IFNr-mediated PD-L1 axis. These results indicate that EGF exacerbates PD-L1 by increasing the protein levels of STAT1 to enforce the IFNr-JAK1/2-mediated signaling axis in selected EGFR-positive cancers. The inhibition of EGFR by afatinib significantly reduced PD-L1 and may be a potential strategy for enhancing immunotherapeutic efficacy.

Role of Immunotherapy for Oncogene-Driven Non-Small Cell Lung Cancer

The clinical application of immune checkpoint inhibitors (ICIs) has led to dramatic changes in the treatment strategy for patients with advanced non-small cell lung cancer (NSCLC). Despite the observation of improved overall survival in NSCLC patients treated with ICIs, their efficacy varies greatly among different immune and molecular profiles in tumors. Particularly, the clinical significance of ICIs for oncogene-driven NSCLC has been controversial. In this review, we provide recent clinical and preclinical data focused on the relationship between oncogenic drivers and immunological characteristics and discuss the future direction of immunotherapy in NSCLC patients harboring such genetic alterations.

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.