Phase II study of afatinib, an irreversible ErbB family blocker, in demographically and genotypically defined lung adenocarcinoma

HER2 Alterations in Non-Small Cell Lung Cancer: Biologico-Clinical Consequences and Interest in Therapeutic Strategies

Lung cancer stands as the first cause of death by cancer in the world. Despite the improvement in patients' outcomes in the past decades through the development of personalized medicine approaches, a substantial portion of patients remains ineligible for targeted therapies due to the lack of a "druggable" molecular target. HER2, a receptor tyrosine kinase member of the EGFR/ErbB family, is known to show oncogenic properties. In this review, we focus on the different HER2 dysregulation mechanisms that have been observed in non-small cell lung cancer (NSCLC): gene mutation, gene amplification, protein overexpression and protein hyper-phosphorylation, the latter suggesting that HER2 dysregulation can occur independently of any molecular aberration. These HER2 alterations inevitably have consequences on tumor biology. Here, we discuss how they are not only involved in abnormal proliferation and survival of cancer cells but also potentially in increased angiogenic properties, mesenchymal features and tumor immune escape. Finally, we review the impact of these HER2 alterations in various therapeutic approaches. While standard chemotherapy and groundbreaking immunotherapy seem rather ineffective for HER2-altered NSCLCs, the development of HER2-targeted therapies such as tyrosine kinase inhibitors, anti-HER2 antibodies and especially antibody-drug conjugates could provide new hopes for patients.

Opportunities and Challenges for a Histology-Agnostic Utilization of Trastuzumab Deruxtecan

PURPOSE OF REVIEW

This review delves into the prospects and challenges offered by a potential pan-histological utilization of trastuzumab deruxtecan (T-DXd) in patients with advanced solid tumors.

RECENT FINDINGS

The HER2-targeted antibody-drug conjugate (ADC) T-DXd has shown broad activity across cancer types, with current indications for patients with biomarker-selected breast, gastric, and non-small-cell lung cancer and relevant activity observed in multiple histology-specific trials. Moreover, two recently reported phase 2 trials (DESTINY-Pantumor02 and HERALD) have supported the potential for a pan-cancer utilization of this ADC in patients with advanced cancers expressing HER2 or with HER2 amplifications. By improving the delivery of cytotoxic chemotherapy, ADCs have allowed for meaningful clinical advantages in broad populations of cancer patients, often leading to survival advantages over conventional chemotherapy. Notably, the broad spectrum of activity of certain ADCs has led to the hypothesis of a histology-agnostic utilization based on detecting specific biomarkers, similar to what is already established for certain targeted treatments and immunotherapy. To date, T-DXd has shown the broadest activity across cancer types, with current approvals in breast, gastric, and lung cancer, and relevant antitumor activity observed in a multiplicity of additional cancer types. The optimization of the drug dose, identification of predictive biomarkers, and clarification of mechanisms of resistance will be critical steps in view of a pan-histological expansion in the use of T-DXd.

Efficacy and safety of a pyrotinib-based regimen in non-small cell lung cancer patients harboring HER2 alterations: A real-world retrospective study

BACKGROUND

Pyrotinib, a novel irreversible pan-HER tyrosine kinase inhibitor, has been approved for the treatment of HER2-positive metastatic breast cancer in China. The aim of this study was to evaluate the efficacy and safety of pyrotinib in advanced nonsmall cell lung cancer (NSCLC) patients with HER2 alterations in real-world practice.

MATERIALS AND METHODS

A retrospective analysis of advanced NSCLC with HER2 mutations or amplifications who received pyrotinib-based treatment at the Qilu Hospital in Shandong University was performed. The primary end points were objective response rate and safety. The secondary end points were progression-free survival, disease control rate, and overall survival.

RESULTS

Twenty three eligible patients from a single center were enrolled between June 2019 and March 2023; among them, 21 had HER2 mutation and two harbored HER2 amplification. Evaluation of the efficacy in 21 patients revealed an objective response rate of 28.6% (6/21; 95% confidence interval [CI]: 7.5%-49.6%) and disease control rate of 85.7% (18/21). The median progression-free survival and overall survival were 7.7 months (95% CI: 6.07-9.33) and 20.8 months (95% CI: 8.42-33.18), respectively. The most common adverse events (AEs) included diarrhea (n = 14, 60.9%), nausea (n = 5, 21.7%), and liver dysfunction (n = 5, 21.7%). Seven patients (7/23, 30.4%) had grade 3-4 AE; no grade 5 AE was observed. Furthermore, one patient (1/23, 4.3%) experienced dose withdrawal and two (2/23, 8.7%) presented with dose reduction symptoms.

CONCLUSION

Pyrotinib-based therapy showed promising antitumor activity and acceptable safety in advanced NSCLC patients with HER2 alterations.

Deciphering the Impact of HER2 Alterations on Non-Small-Cell Lung Cancer: From Biological Mechanisms to Therapeutic Approaches

Despite the recent increase in the number of types of treatments, non-small-cell lung cancer (NSCLC) remains the major cause of death from cancer worldwide. So, there is an urgent need to develop new therapeutic strategies. The HER2 gene codes for tyrosine kinase receptor whose alterations are known to drive carcinogenesis. HER2 alterations, including amplification, mutations, and overexpression, have been mainly described in breast and gastric cancers, but up to 4% of NSCLC harbor actionable HER2 mutations. HER2-targeted therapy for NSCLC with trastuzumab, pertuzumab, and trastuzumab emtansine has failed to demonstrate an improvement in survival. Nevertheless, recent data from phase II trials have shed light on promising specific therapies for HER2-mutant NSCLC such as trastuzumab deruxtecan. Herein, we aimed to provide an updated review on the biology, epidemiology, molecular testing, and therapeutic strategies for NSCLC with HER2 molecular alterations.

HER2 in Non-Small Cell Lung Cancer: A Review of Emerging Therapies

Simple Summary

There are growing data on targeting HER2 alterations, which include gene mutations, gene amplifications, and protein overexpression, for non-small cell lung cancer (NSCLC). Currently, there are limited targeted therapies approved for NSCLC patients with HER2 alterations, and this remains an unmet clinical need. There has been an influx of research on antibody–drug conjugates, monoclonal antibodies, and tyrosine kinase inhibitors. This review discusses the diagnostic challenges of HER2 alterations in NSCLC and summarizes recent progress in HER2 targeted drugs for both clinicians and researchers treating this patient population.

Abstract

Human epidermal growth factor receptor 2 (HER2), a member of the ERBB family of tyrosine kinase receptors, has emerged as a therapeutic target of interest for non-small cell lung cancer (NSCLC) in recent years. Activating HER2 alterations in NSCLC include gene mutations, gene amplifications, and protein overexpression. In particular, the HER2 exon 20 mutation is now a well clinically validated biomarker. Currently, there are limited targeted therapies approved for NSCLC patients with HER2 alterations. This remains an unmet clinical need, as HER2 alterations are present in 7–27% of de novo NSCLC and may serve as a resistance mechanism in up to 10% of EGFR mutated NSCLC. There has been an influx of research on antibody–drug conjugates (ADCs), monoclonal antibodies, and tyrosine kinase inhibitors (TKIs) with mixed results. The most promising therapies are ADCs (trastuzumab-deruxtecan) and novel TKIs targeting exon 20 mutations (poziotinib, mobocertinib and pyrotinib); both have resulted in meaningful anti-tumor efficacy in HER2 mutated NSCLC. Future studies on HER2 targeted therapy will need to define the specific HER2 alteration to better select patients who will benefit, particularly for HER2 amplification and overexpression. Given the variety of HER2 targeted drugs, sequencing of these agents and optimizing combination therapies will depend on more mature efficacy data from clinical trials and toxicity profiles. This review highlights the challenges of diagnosing HER2 alterations, summarizes recent progress in novel HER2-targeted agents, and projects next steps in advancing treatment for the thousands of patients with HER2 altered NSCLC.

Clinical characteristics and prognostic factors of patients with non-small cell lung cancer having HER2 alterations

PURPOSE

Human epidermal growth factor 2 (HER2) alterations are found in approximately 2%-5% of non-small cell lung cancer (NSCLC). This study aimed to evaluate the clinical characteristics of patients with NSCLC having HER2 alterations in China and the differences compared with Western counterparts and also perform a prognostic analysis.

MATERIAL AND METHODS

A total of 1300 patients diagnosed with NSCLC from January 2017 to December 2020 were included. Their clinical characteristics were retrospectively recorded. The gene expression profiles and clinical information of 20 patients having altered HER2 were downloaded from the Cancer Genome Atlas database and compared, and the prognostic factors affecting the Chinese population were analyzed. If tissues were sufficient, the overexpression was assessed by immunohistochemical staining.

RESULTS

Among 39 (3.0%) patients with HER2 alterations, 31 patients (79.5%) had HER2 mutations. HER2 insertion mutation in exon 20 was the most common type (A775_G776 ins YVMA). Seven patients (17.9%) had amplification, and one had both. The HER2 kinase domain was most commonly mutated. A majority of patients in the study were young-aged with no smoking history; 66.7% had stage III/IV adenocarcinoma. Compared with Chinese patients, HER2 alterations in Western counterparts were mostly associated with old age, previous smoking, and stages I and II at diagnosis. The most common type of HER2 alteration was HER2 amplification; one patient had coexistence of HER2 gene amplification and fusion. The furin-like cysteine-rich region was most commonly mutated. The median overall survival (OS) of the Chinese patients was 41 months. The univariate analysis showed that age > 60 years, no surgical treatment, no liver or renal cysts on imaging, and maximum tumor diameter ≥ 4.25 cm were significantly associated with poor OS. The multivariate analysis showed that age, presence of surgery, and no hepatic or renal cysts were independent prognostic factors for OS. Chemotherapy achieved better outcomes, and HER2 mutations were not associated with HER2 amplification and overexpression.

CONCLUSIONS

This study was novel in comprehensively investigating the clinical and molecular characteristics of patients in Chinese and Western populations, and in analyzing the factors affecting the prognosis of Chinese patients. It provided critical data for future therapies against HER2-altered NSCLC.

NSCLC as the Paradigm of Precision Medicine at Its Finest: The Rise of New Druggable Molecular Targets for Advanced Disease

Standard treatment for advanced non-small cell lung cancer (NSCLC) historically consisted of systemic cytotoxic chemotherapy until the early 2000s, when precision medicine led to a revolutionary change in the therapeutic scenario. The identification of oncogenic driver mutations in EGFR, ALK and ROS1 rearrangements identified a subset of patients who largely benefit from targeted agents. However, since the proportion of patients with druggable alterations represents a minority, the discovery of new potential driver mutations is still an urgent clinical need. We provide a comprehensive review of the emerging molecular targets in NSCLC and their applications in the advanced setting.

Rare driver alterations in nonsmall cell lung cancer: novel targeted drugs

PURPOSE OF REVIEW

The current review presents clinically relevant driver alterations in nonsmall cell lung cancer (NSCLC) and the targeted treatments currently available for clinical use as well as those in clinical trials and advanced stages of drug development.

RECENT FINDINGS

Mesenchymal-epithelial transition factor, human epidermal growth factor receptor 2, proto-oncogene B-RAF (BRAF), proto-oncogene tyrosine-protein kinase ROS (ROS1), rearranged during transfection (RET) and neurotrophic tyrosine kinase are rare genetic driver alterations, each present in a small subset of patients with NSCLC. Treatments targeting BRAF, ROS1, RET and neurotrophic tyrosine kinase are approved in Europe, and promising treatments targeting mesenchymal-epithelial transition factor and human epidermal growth factor receptor 2 are available in clinical trials and compassionate use programs. The response rates, duration of response and tolerability observed in trials of targeted drugs in this setting are presented in detail here.

SUMMARY

While rare driver alterations are, by definition, rare, their recognition can change the course of NSCLC for those patients affected. Targeted treatments for many rare driver alterations are well tolerated and effective. Screening for molecular changes in advanced NSCLC should include screening for rare drivers, and patients should be directed to clinical trials in setting where treatment of the driver alterations is not otherwise available.

Antibody-drug conjugates: A promising novel therapeutic approach in lung cancer

Antibody-drug conjugates (ADCs) are rapidly establishing their place and have shown promising preliminary data in lung cancer with impressive response rates and survival outcomes in previously treated patients.There are several ADCs currently in clinical trials for NSCLC and small cell lung cancer (SCLC). These ADCs often have different targets which include HER2, HER3, TROP2, CEACAM5, and MET in NSCLC and DLL3 in SCLC.Here we review the safety, and efficacy of newer ADCs in lung cancer including ado-trastuzumab emtansine, trastuzumab deruxetecan, patritomab deruxetecan, datopotamab deruxetecan, sacituzumab govitecan, SAR408701, Telisotuzumab vedotin, rovalpituzumab tesirine, lorvotuzumab mertansine, and sacituzumab govitecan.  Several novel methods are underway to improve the safety and efficacy of ADCs which include increasing the drug to antibody ratio (DAR), the potency of the payload, using more innovative payloads and replacing the antibody.

HER2 Aberrations in Non-Small Cell Lung Cancer: From Pathophysiology to Targeted Therapy

While human epidermal growth factor receptor 2 (HER2) aberrations have long been described in patients with non-small cell lung cancer (NSCLC), they have only recently been effectively targeted. Unlike patients with breast cancer, NSCLC patients can harbor either HER2-activating mutations or HER2 amplification coupled with protein overexpression. The latter has also been the case for patients with acquired resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). As preclinical data continue to accumulate, clinical trials evaluating novel agents that target HER2 have produced promising preliminary results. Here, we review existing data on HER2 aberrations in NSCLC. Starting from HER2 biology in normal and disease processes, we summarize discrepancies in HER2 diagnostic assays between breast cancer and NSCLC. Finally, to dissect the therapeutic implications of HER2-activating mutations versus gene amplification and/or protein overexpression, we present data from prospective clinical trials that have employed distinct classes of agents to target HER2 in patients with NSCLC.

Clinical Characteristics and Prognosis of HER2 Gene Phenotype in Patients with Non-Small Cell Lung Cancer

Introduction

We aim to investigate the relationship between HER2 gene phenotype and clinical characteristics, distribution and prognosis of non-small cell lung cancer (NSCLC) patients.

Methods

A total of 249 NSCLC patients admitted to the oncology department of our hospital from January 2015 to January 2018 were retrospectively analyzed. The clinicopathological information, CT signs, clinical efficacy and long-term prognosis were collected and compared.

Results

A total of 249 NSCLC patients underwent HER2 gene testing, 21 of them (8.43%) complied with HER2 alterations [HER2 (+)], and there were significant differences in tumor stages among patients with different HER2 phenotypes (P<0.05). Among 21 NSCLC patients with HER2 (+), HER2 gene mutation was found in 17 patients (81%), and HER2 gene amplification in 4 patients (19%). Among the HER2 mutations, 12 cases (57%) were 20 exon mutations, and 5 cases (19%) were other mutations. Analysis of CT signs showed that border lobulation/burr, necrosis sign and pleural depression were correlated with HER2 gene mutation (P<0.05). The incidence of EGRF mutation in HER (+) patients was significantly lower than that in HER (-) patients (P<0.05), but there was no significant difference in the incidence of ALK gene mutation among different HER phenotypes (P>0.05). The disease control rate of HER2 (+) patients was significantly lower than that of HER2 (-) patients, and the 12-month progression-free survival rate and survival rate of HER2 (+) patients were significantly higher than those of HER2 (-) patients (P<0.05). There was no significant difference in the incidence of ADR among HER2 patients with different phenotypes, but the incidence of ADR (adverse drug reaction) in HER2 (+) patients with Grade 3 or 4 was significantly higher than that in the control group (P<0.05).

Discussion

The incidence of HER2 gene mutations in NSCLC patients is relatively low, but it is far commoner in patients with stage IIIB~IV, among which exon 20 mutations are the most prevalent. In CT signs, the lesion lobulated sign/spiculated sign, necrosis signs, and pleural depression signs are related to HER2 gene mutations. In addition, HER2 gene mutations play a crucial role in the clinical prognosis and treatment safety of patients.

The storm of NGS in NSCLC diagnostic-therapeutic pathway: How to sun the real clinical practice

The increasing number of approved drugs along with next generation sequencing (NGS) technologies look out as potential revolution of biomolecular characterization of non-small-cell lung cancer (NSCLC). Nevertheless, several aspects impact on success rate of NGS in clinical practice: a multidisciplinary approach and thorough knowledge of strengths and limits of each technologic diagnostic tool are required. Crucial preliminary step is the selection of the best available sample before testing, aware of clinical condition and setting of disease. Genomic data should be than integrated in the clinical context and matched with available therapeutic options; Molecular Tumor Boards (MTB) are worldwide emerging interdisciplinary groups implemented to transfer the impact of precision medicine in clinical practice. In order to guarantee equity in treatment, these considerations should find their application widely and rapidly. Aim of this review is offering an overview of emerging biomarkers, relative upcoming targeted drugs, and new diagnostic chances with an authors' perspective about a real-life diagnostic-therapeutic algorithm useful for daily clinical practice.

Efficacy of targeted therapy in patients with HER2-positive non-small cell lung cancer: A systematic review and meta-analysis

Anti-human epidermal growth factor receptor 2 (HER2) therapy is an effective treatment for HER2-positive gastric and breast malignancies. However, the efficacy of HER2-targeted therapy in non-small cell lung cancer (NSCLC) patients with HER2 alterations remains controversial. We searched studies on HER2-targeted therapy in NSCLC patients that reported objective response rate (ORR), disease control rate (DCR) and progressionfree survival (PFS) published from database inception to 30 May 2021. A total of 32 trials involving 958 patients were included. The ORRs of HER2-TKIs targeted therapy, humanised monoclonal antibody, trastuzumab-based treatment and antibody-drug conjugate (ADC) (T-DM1) were 22% (95% CI 11-31), 23% (95% CI 20-65), 26% (95% CI 14-39) and 16% (95% CI _6-37), while that of ADC (DS-8201) was 60% (95% CI 35-85). The DCRs of these groups were 59% (95% CI 49-69), 39% (95% CI _9-88), 63% (95% CI 37-89), 31% (95% CI 4-58) and 87% (95% CI 62-112), respectively. In the subgroup analysis, numerically higher ORRs and DCRs were observed in the poziotinib (38%; 75%) and pyrotinib (35%; 83%) groups. The median PFSs of these groups were 5.51 months, 3.09 months, 4.61 months, 2.65 months and 12.04 months, respectively. HER2-targeted therapy can be considered an acceptable treatment strategy for NSCLC patients with HER2 alterations. In particular, ADC (DS-8201), pyrotinib and poziotinib demonstrated promising anti-tumour activity in HER2-positive NSCLC.

HER2 Amplification in Advanced NSCLC Patients After Progression on EGFR-TKI and Clinical Response to EGFR-TKI Plus Pyrotinib Combination Therapy

BACKGROUND

HER2 (or ERBB2) amplification is an important mechanism for acquired resistance to EGFR tyrosine kinase inhibitors (TKI). The benefits of HER2-targeted therapy have been limited. Herein, we investigated the molecular and clinical patterns of HER2 amplification in non-small cell lung cancer (NSCLC) patients during progression on EGFR-TKIs and the potential of combining EGFR-TKI and pyrotinib to overcome resistance.

METHODS

In this study, 1,637 NSCLC cases from Geneseeq after progression of EGFR-TKIs were screened and analyzed by next generation sequencing (NGS), in which 48 patients with HER2 amplification were eligible and enrolled. A total of 403 patients from Sun Yat-sen University Cancer Center (SYSUCC) were screened and five patients with concomitant EGFR mutations and HER2 amplification were retrospectively collected to assess the effect of afatinib or combination of EGFR-TKI and pyrotinib.

RESULTS

In the 48 patients from the Geneseeq cohort, 27 (56.2%) patients suffered from resistance of 1st/2nd generation EGFR-TKI, and 21 (43.8%) patients from 3rd generation. As for the five patients forming the SYSUCC cohort, three patients were treated with afatinib, one achieved partial response (PR) with progression-free survival (PFS) of 6 months and two quickly developed disease progression. Two patients were treated with EGFR-TKIs plus pyrotinib, one receiving gefitinib plus pyrotinib achieved PR with PFS of 8 months and benefited from osimertinib plus pyrotinib for 3 months till data-off; one receiving osimertinib plus pyrotinib achieved SD for 4 months till data-off. The most common co-occurring alteration was TP53 (91.7%) in the mutation profile of the 48 patients from the Geneseeq cohort, and four patients had TP53 co-mutations of the five patients from the SYSUCC cohort.

CONCLUSION

In this study, we detected 7% HER2 amplification present in EGFR-TKIs resistance. Patients with concomitant EGFR mutation and HER2 amplification may derive clinical benefit from therapies that target both EGFR and HER2.

Targeting HER2 in non-small-cell lung cancer (NSCLC): a glimpse of hope? An updated review on therapeutic strategies in NSCLC harbouring HER2 alterations

Non-small-cell lung cancer (NSCLC) harbouring HER2 alterations is now considered a distinct molecular subtype. The activation of HER2 in NSCLC occurs via three mechanisms, i.e. gene mutation (1%-4% of cases), gene amplification (2%-5%) and protein overexpression (2%-30%), with different prognostic and predictive outcomes. So far, non-selective tyrosine kinase inhibitors (TKIs) have shown a minor benefit in HER2-mutant NSCLC patients with objective response rates (ORRs) ranging from 0% to 19%. Trastuzumab-based chemotherapy was not found to be superior to chemotherapy alone [median progression-free survival (PFS) 6.1 versus 7 months, respectively] and dual HER2 antibody blockade with trastuzumab and pertuzumab had limited efficacy (ORR 13%-21%). In contrast, novel more selective HER2 TKIs such as poziotinib and pyrotinib have shown a promising activity in HER2-mutant pre-treated NSCLC patients, with response rates up to 38% and 44%, respectively. The most encouraging data come from phase II studies that evaluated the antibody–drug conjugates (ADCs) ado-trastuzumab–emtansine and trastuzumab–deruxtecan in patients with HER2-mutant NSCLC, with response rates of 50% and 62%, respectively. These agents are bringing hope to the management of HER2-altered NSCLC. Moreover, a paradigm shift from monotherapies towards combinations of agents with distinct mechanisms of action, such as ADCs with irreversible TKIs or immune checkpoint inhibitors, is already taking place and will change the therapeutic landscape of HER2-driven NSCLC. This paper provides a practical, concise and updated review on the therapeutic strategies in NSCLC with HER2 molecular alterations.

•

Activation of Her2 in NSCLC occurs via gene mutation, amplification or protein overexpression.

•

Selective Her2 TKIs like poziotinib and pyrotinib induced responses in up to 44% of pre-treated Her2-mutant NSCLC patients.

•

ADCs trastuzumab–emtansine and trastuzumab–deruxtecan showed impressive response rates in 62% of Her2-mutant NSCLC patients.

•

Ongoing studies evaluating combination strategies may help improve the therapeutic landscape in Her2-dependent NSCLC.

Progress in Treatment of Non-Small Cell Lung Cancer Harboring HER2 Aberrations

Epidermal growth factor receptor 2 (HER2/ErbB2/neu), a member of ErbB receptor tyrosine kinase family, forms homo- or heterodimers with ErbB1 (HER1/EGFR), ErbB3 (HER3), or ErbB4 (HER4), to activate signal transduction pathways and promote proliferation, differentiation and tumorigenesis. Preliminary clinical trials of monoclonal antibodies, antibody conjugates and small-molecule tyrosine kinase inhibitors targeting HER2 have indicated that HER2 is a potential therapeutic target in non-small cell lung cancer (NSCLC). HER2 aberrations in NSCLC patients mainly include mutation, amplification, and overexpression. While there are significant differences in the outcome of NSCLC with these HER2 changes, no consensus has been reached for the incidence, detection method and targeted treatments for the three types of HER2 aberration. HER2 mutation is generally considered to have more clinical relevance and response to HER2-targeted therapies. In this review, we discuss HER2 alterations in NSCLC, including diagnostic challenges and treatment strategies particular to the HER2 mutation.

The rapidly evolving landscape of novel targeted therapies in advanced non-small cell lung cancer

Lung cancer is a highly heterogeneous disease often driven by well-characterized driver mutations. Although the best studied are common alterations in the epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) oncogenes, rapid advances in molecular characterization has led to the development of novel therapeutics that inhibit additional oncogenic alterations in advanced NSCLC. The literature search identified 62 eligible phase I/II clinical trials or integrated analyses of assessing novel targeted agents against the following molecular alterations: ROS1-rearranged, BRAF V600E-mutant, NTRK-rearranged, MET-altered, uncommon EGFR-mutant, RET-rearranged, HER2-positive, KRAS G12C-mutant and NRG1-rearranged. This rapidly evolving field has produced many new targeted treatment options and promising outcomes have led to the FDA approval of seven novel agents for use in ROS1-rearranged, BRAF V600E-mutant, NTRK-rearranged, MET exon 14 skipping-mutant or RET-rearranged advanced NSCLC. Research continues at a rapid pace, with a number of phase III trials underway to fully evaluate new promising agents under development for improving outcomes in patients with NSCLC harboring distinct molecular subtypes. This review will provide a comprehensive summary of existing data as well as a user-friendly guide on the current status of novel targeted therapy in oncogene-driven advanced NSCLC.

A narrative review of advances in treatment and survival prognosis of HER2-positive malignant lung cancers

Human epidermal growth factor receptor 2 (HER2), as a receptor tyrosine kinase of EGF receptor family, whose mutation is often associated with even if less frequency but poor prognosis and shorter survival in pulmonary malignant tumor. HER2 status include mutation, overexpression, amplification and also some rare genotypes, detected by next generation sequencing (NGS), immunohistochemistry (IHC), and also fluorescence in situ hybridization (FISH). Different genotypes represent different therapeutic targets and indicate different clinical prognosis concluded by previous studies. Unfortunately, no standard guidelines for first-line treatment are widely recognized, and current therapeutic schedules include chemotherapy, radiotherapy, targeted therapy, and immunotherapy. Especially for patients with advanced metastasis, chemotherapy is based as a systemic therapy using studies of breast cancer or EGFR-positive lung adenocarcinoma as a template. Studies already explored treatment including EGFR tyrosine kinase inhibitors (TKIs) such as gefitinib and afatinib, and also trastuzumab and its conjugation like HER2-targeted antibody-drug conjugate trastuzumab emtansine (T-DM1) and conjugate trastuzumab deruxtecan (T-DXd). Also, he researches explored combination therapy with chemotherapy and TKIs or monoclonal antibodies. This review describes commonly used therapies for HER2-positive/HER2-overexpression patients and general relationship between genotypes of HER2, drug selection and final prognosis in order to provide suggestions for future diagnosis and treatment.

Treatment of Rare Mutations in Patients with Lung Cancer

Lung cancer is a worldwide prevalent malignancy. This disease has a low survival rate due to diagnosis at a late stage challenged by the involvement of metastatic sites. Non-small-cell lung cancer (NSCLC) is presented in 85% of cases. The last decade has experienced substantial advancements in scientific research, leading to a novel targeted therapeutic approach. The newly developed pharmaceutical agents are aimed towards specific mutations, detected in individual patients inflicted by lung cancer. These drugs have longer and improved response rates compared to traditional chemotherapy. Recent studies were able to identify rare mutations found in pulmonary tumors. Among the gene alterations detected were mesenchymal epithelial transition factor (MET), human epidermal growth factor 2 (HER2), B-type Raf kinase (BRAF), c-ROS proto-oncogene (ROS1), rearranged during transfection (RET) and neurotrophic tyrosine kinase (NTRK). Ongoing clinical trials are gaining insight onto possible first and second lines of medical treatment options intended to enable progression-free survival to lung cancer patients.

Impact of the generation of EGFR-TKIs administered as prior therapy on the efficacy of osimertinib in patients with non-small cell lung cancer harboring EGFR T790M mutation

Background

There are few studies that directly compare the effects of osimertinib on patients with non‐small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) T790M mutation between the generation of prior EGFR tyrosine kinase inhibitors (TKIs).

Methods

We retrospectively reviewed clinical data from the medical records of consecutive patients with advanced NSCLC who had developed resistance to first‐ or second‐generation EGFR‐TKIs due to EGFR T790M mutation and were subsequently treated with osimertinib at Juntendo University Hospital. In patients with available tumor samples, target amplicon sequencing analyses were performed to explore the genetic biomarkers.

Results

A total of 38 patients with NSCLC harboring EGFR T790M mutation were treated with osimertinib. Eight patients were classified into group A (afatinib followed by osimertinib) and 30 patients were classified into group B (first‐generation EGFR‐TKI followed by osimertinib). Progression‐free survival (PFS) was significantly longer in group A than in group B (median PFS; not reached vs. 11.0 months, P = 0.018). Fourteen patients had available tissue samples collected before osimertinib treatment for target sequencing. In group A we found no additional mutations, other than EGFR T790M mutation. On the other hand, there were three samples in which other mutations emerged, in addition to EGFR T790M mutation, in group B.

Conclusions

PFS of osimertinib was significantly longer in patients with NSCLC harboring EGFR T790M mutation after treatment with afatinib than in patients after treatment with first generation EGFR‐TKIs. Additional mutations other than EGFR T790M may affect the efficacy of osimertinib treatment.

Key points

Significant findings of the study:

PFS of osimertinib was significantly longer in patients with NSCLC harboring EGFR T790M mutation after treatment with afatinib than in patients after treatment with first generation EGFR‐TKIs.

What this study adds:

Additional mutations other than EGFR T790M may affect the efficacy of osimertinib treatment.

Targeting HER2 Alterations in Non–Small-Cell Lung Cancer: A Comprehensive Review

PURPOSE

HER2 is a critical gene that drives various solid tumors in addition to those of breast cancer. For example, HER2 plays a role in non–small-cell lung cancer (NSCLC). Overexpression, amplification, and point mutations in HER2 have been described in patients with NSCLC; however, the potential roles of these alterations remain unclear.

METHODS

We summarize the evidence regarding the distinct impacts of different HER2 aberrations on antitumor agents. Also, we update the therapeutic efficacy of HER2-targeted agents, including anti-HER2 antibodies, antibody-drug conjugates, and small-molecule tyrosine kinase inhibitors, tested in HER2-aberrant NSCLC.

RESULTS

Although these drugs are not yet standard treatments, certain patients may benefit from these therapies. In this review, we aim to provide an improved understanding of HER2 aberrations in NSCLC, including NSCLC biology and the impacts of each aberration on prognosis and standard treatment. We also highlight the potential of novel anti-HER2 therapies approved by regulatory bodies and those in clinical development.

CONCLUSION

Compared with HER2 amplification or overexpression, HER2 mutations, especially HER2 exon 20 mutations, are emerging as the most clear targetable driver for HER2-directed therapies in lung cancer. De novo and inducible HER2 pathway activation need to be differentially managed. Further investigations with new strategies are needed.

HER2 Exon 20 Insertion Mutations in Lung Adenocarcinoma: Case Series and Response to Pyrotinib

HER2 mutations have emerged as oncogenic driver gene mutations in non-small cell lung cancer (NSCLC), which have not been described in detail like other driver gene mutations. Here, 295 patients with advanced lung adenocarcinoma were retrospectively screened for HER2 mutations using next-generation sequencing (NGS), and the positive cases were validated by Sanger sequencing. We identified five cases with HER2 exon 20 insertions, representing 1.7% of 295 lung adenocarcinomas. Among them, four different subtypes of HER2 exon 20 insertions were identified, including a rare subtype G778_S779insCPG never reported before with a partial response (PR) to pyrotinib and progression-free survival (PFS) of 12.8 months. Our findings reveal that HER2 exon 20 insertion mutations were detected in a small subset of lung adenocarcinomas. Given the different drug sensitivities, determining the mutation subtype by next-generation sequencing at the time of diagnosis might make sense.

Is There a Role for Multiple Lines of Anti-HER2 Therapies Administered Beyond Progression in HER2-Mutated Non-Small Cell Lung Cancer? A Case Report and Literature Review

Oncogene-addicted non-small cell lung cancer (NSCLC) comprises a number of distinct disease subtypes, each of which is characterised by druggable genetic alterations. Among them, the receptor tyrosine kinase protein human epidermal receptor 2 (HER2) is occasionally found deregulated via gene mutation and/or amplification and/or protein overexpression. HER2 mutation, in particular, is a relatively rare condition which occurs in 1-4% of NSCLC patients, especially in those with adenocarcinoma histology and a never/light smoking history. However, the clinical relevance of a HER2 mutation in NSCLC relies on the fact that this genetic alteration has been associated with sensitivity to anti-HER2 therapies such as the monoclonal antibody trastuzumab or the pan-HER-tyrosine kinase inhibitor poziotinib. Here we describe the case of a NSCLC patient with an activating exon 20 G776VinsC mutation in the HER2 gene who responded well to multiple lines of trastuzumab-based therapies administered beyond progression and poziotinib given sequentially. In this specific case, the discovery of a druggable genetic alteration such as a mutation in the HER2 gene allowed for long-term control of the disease through the use of highly effective anti-HER2 therapies.

Molecular therapeutic targets in non-small cell lung cancer

INTRODUCTION

Several targetable genetic alterations have been identified in non-small cell lung cancers (NSCLC) and drugs targeting these alterations have been approved for the management of advanced NSCLC patients. Driver mutations with emerging clinical trial data include EGFR exon 20 insertion mutations, MET amplification, KRAS G12 C point mutations, RET rearrangements, HER2 amplification and mutations, and FGFR amplification and translocations.

AREAS COVERED

We reviewed English-language articles indexed in Medline and PubMed up to the 1^st of June 2020. In addition, the proceedings of major conferences were reviewed for relevant abstracts. We report data published regarding targeted therapies which are currently approved and for those which are emerging in advanced or metastatic NSCLC.

EXPERT REVIEW

While these drugs have been shown to be efficacious and tolerable, resistance almost always develops. Though next-generation tyrosine kinase inhibitors (TKIs) have been developed, the appropriate sequencing of these drugs is not clear. Evaluating combination therapies to prevent or delay the onset of resistance and understanding mechanisms of resistance are critical areas of emerging research.

Efficacy and safety of afatinib for non-small-cell lung cancer: state-of-the-art and future perspectives

INTRODUCTION

Afatinib is a second-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, acting as an irreversible and multitarget blocker of ErbB family members. Afatinib is currently approved for advanced non-small-cell lung cancer (NSCLC) harboring common and uncommon sensitizing EGFR mutations and for squamous NSCLC patients progressing after first-line platinum-based chemotherapy.

AREAS COVERED

This review summarizes the efficacy and safety profile of afatinib compared with chemotherapy and other EGFR TKIs, in order to evaluate its characteristics and potential role in the increasingly complex treatment landscape of EGFR-mutant lung cancer. Future perspectives and innovative drug combinations are also discussed.

EXPERT OPINION

Afatinib has been demonstrated to improve efficacy and quality of life compared with chemotherapy with a managed toxicity profile. However, in recent years, the increasing availability of different treatment options for advanced EGFR-mutant NSCLC has made the current treatment scenario more complicated, with an increasing need of new and deeper scientific data. In this light, the identification and validation of potential clinicopathological and/or molecular predictors of benefit, as well as the clarification of resistance mechanisms, may help to clarify the most appropriate treatment strategies and sequences for EGFR-mutant patients.

New Targets in Lung Cancer (Excluding EGFR, ALK, ROS1)

PURPOSE OF REVIEW

Over the last two decades, the identification of targetable oncogene drivers has revolutionized the therapeutic landscape of non-small cell lung cancer (NSCLC). The extraordinary progresses made in molecular biology prompted the identification of several rare molecularly defined subgroups. In this review, we will focus on the novel and emerging actionable oncogenic drivers in NSCLC.

RECENT FINDINGS

Recently, novel oncogene drivers emerged as promising therapeutic targets besides the well-established EGFR mutations, and ALK/ROS1 rearrangements, considerably expanding the list of potential exploitable genetic aberrations. However, the therapeutic algorithm in these patients is far less defined. The identification of uncommon oncogene drivers is reshaping the diagnostic and therapeutic approach to NSCLC. The introduction of novel highly selective inhibitors is expanding the use of targeted therapies to rare and ultra-rare subsets of patients, further increasing the therapeutic armamentarium of advanced NSCLC.

The force of HER2 - A druggable target in NSCLC?

Since several years targeted therapy has been part of treatment in NSCLC in subsets of patients with specific genetic alterations. One of these alterations involves HER2, a member of the ERBB family of tyrosine kinase receptors. Despite that HER2 alterations in NSCLC have been studied for years, there is still no consensus about subgroup definitions. In this review HER2 alterations in NSCLC are discussed, including diagnostic challenges and treatment strategies. Three principal mechanisms of HER2 alterations can be identified: HER2 protein overexpression, HER2 gene amplification and HER2 gene mutations. There are several methods for the detection of HER2 "positivity" in NSCLC, but no gold standard has been established. Laboratory methods for assessment of HER2 positivity in NSCLC include immunohistochemistry (IHC) for protein overexpression and fluorescent in situ hybridization (FISH) and next generation sequencing (NGS) for genetic alterations. Many trials testing HER2 targeted therapy in HER2 altered NSCLC has not lead to a renewed standard of care for this group of patients. Therefore, today the (re)search on how to analyse, define and treat HER2 alterations in NSCLC continues. Still there is no consensus about HER2 subgroup definitions and results of the many trials studying possible treatment strategies are inconclusive. Future research should focus on the most important missing link, whether all HER2 alterations are relevant oncogenic drivers and whether it should be considered as a therapeutic target in NSCLC.

Use of Ex Vivo Patient-Derived Tumor Organotypic Spheroids to Identify Combination Therapies for HER2 Mutant Non-Small Cell Lung Cancer

PURPOSE

Evaluating drug responses using primary patient-derived cells ex vivo represents a potentially rapid and efficient approach to screening for new treatment approaches. Here, we sought to identify neratinib combinations in HER2 mutant non-small cell lung cancer (NSCLC) patient xenograft-derived organotypic spheroids (XDOTS) using a short-term ex vivo system.

EXPERIMENTAL DESIGN

We generated two HER2-mutant NSCLC PDX models [DFCI359 (HER2 exon19 755_757LREdelinsRP) and DFCI315 (HER2 exon20 V777_G778insGSP)] and used the PDX tumors to generate XDOTS. Tumor spheroids were grown in a microfluidic device and treated ex vivo with neratinib-based drug combinations. Live/dead quantification was performed by dual-labeling deconvolution fluorescence microscopy. The most efficacious ex vivo combination was subsequently validated in vivo using the DFCI359 and DFCI315 PDXs and a HER2 ^YVMA genetically engineered mouse model.

RESULTS

Both neratinib and afatinib, but not gefitinib, induced cell death in DFCI359 XDOTS. The combinations of neratinib/trastuzumab and neratinib/temsirolimus enhanced the therapeutic benefit of neratinib alone in DFCI315 and DFCI359. The combination of neratinib and trastuzumab in vivo was more effective compared with single-agent neratinib or trastuzumab and was associated with more robust inhibition of HER2 and downstream signaling.

CONCLUSIONS

The XDOTS platform can be used to evaluate therapies and therapeutic combinations ex vivo using PDX tumors. This approach may accelerate the identification and clinical development of therapies for targets with no or few existing models and/or therapies.

Targeting non-small cell lung cancer: driver mutation beyond epidermal growth factor mutation and anaplastic lymphoma kinase fusion

The identification of driver mutations in epidermal growth factor receptor, anaplastic lymphoma kinase, the BRAF and ROS1 genes and subsequent successful clinical development of kinase inhibitors not only significantly improves clinical outcomes but also facilitates the discovery of other novel driver mutations in non-small cell lung cancer. These driver mutations can be categorized into mutations in or near the kinase domain, gene amplification or fusion. In this review, BRAF V600E, EGFR and HER-2 exon 20 mutation, FGFR1-4, K-RAS, MET, neuregulin-1, NRTK, PI3K/AKT/mTOR, RET and ROS1 gene aberration and their therapeutics will be discussed.

Population pharmacokinetics of afatinib and exposure-safety relationships in Japanese patients with EGFR mutation-positive non-small cell lung cancer

To investigate the exposure-safety relationships of afatinib in Japanese population, we performed population pharmacokinetics (PK) analysis of afatinib in Japanese advanced non-small cell lung cancer patients harboring epidermal growth factor receptor mutation. Plasma samples were collected at 0.5-1, 2-3, 8-12, and 24 h after oral afatinib (40 mg) administration on day 1 and day 8. Plasma afatinib concentrations were determined using high-performance liquid chromatography. Data was analyzed following the population approach and using the software Phoenix® NLMETM Version 7.0 software (Certara USA, Inc., Princeton, NJ, USA). From 34 patients, a total of 354 afatinib plasma concentration values were available for the population PK analysis. Significant covariates in the population PK model included aspartate aminotransferase and creatinine clearance on CL/F, and age and body mass index on V/F. Results of simulation based on final PK model indicated that hepatic impairment had a significant effect on afatinib levels in plasma after multiple dosing. Afatinib trough plasma concentrations on day 8 were higher in patients with adverse events of grade 3 or higher. The population PK analysis showed that hepatic impairment affected afatinib PK parameters and contributed to the high inter-patient variability and high plasma concentrations of afatinib following multiple treatments.

Association of ERBB Mutations With Clinical Outcomes of Afatinib- or Erlotinib-Treated Patients With Lung Squamous Cell Carcinoma: Secondary Analysis of the LUX-Lung 8 Randomized Clinical Trial

Importance

Treatment choice for lung squamous cell carcinoma could be aided by identifying predictive biomarkers.

Objective

To assess whether patient outcomes in the LUX-Lung 8 trial were associated with ERBB gene family member aberrations in tumor specimens.

Design, Setting, and Participants

Ad hoc secondary analysis of the LUX-Lung 8 trial conducted at 183 centers in 23 countries from March 30, 2012, to January 30, 2014. Eligible patients had stage IIIB or IV lung squamous cell carcinoma with progressive disease after 4 or more cycles of platinum-based chemotherapy. Tumor genetic analysis (TGA) was performed using next-generation sequencing in a cohort enriched for patients with progression-free survival (PFS) of more than 2 months. Epidermal growth factor receptor (EGFR) expression levels were assessed by immunohistochemistry in a separate cohort of patients from the LUX-Lung 8 population. Associations of PFS and overall survival (OS) with ERBB gene alterations and EGFR expression levels were assessed. This analysis was conducted from February 26, 2015, to June 12, 2017.

Interventions

Patients were randomized 1:1 to treatment with afatinib dimaleate (40 mg/d; n = 398) or erlotinib hydrochloride (150 mg/d; n = 397).

Main Outcomes and Measures

Overall survival, PFS, pooled and individual ERBB gene mutations, ERBB copy number alterations, and EGFR expression.

Results

Tumor specimens from 245 patients were eligible for next-generation sequencing (TGA subset: 132 patients treated with afatinib; 113 patients treated with erlotinib). In this population, outcomes were improved with afatinib vs erlotinib treatment (PFS: median, 3.5 vs 2.5 months; hazard ratio [HR], 0.69; 95% CI, 0.51-0.92; P = .01; OS: median, 8.4 vs 6.6 months; HR, 0.81; 95% CI, 0.62-1.05; P = .12). Of 245 patients in the TGA subset, 53 (21.6%) had tumors with 1 or more ERBB mutations. Among afatinib-treated patients, PFS (median, 4.9 vs 3.0 months; HR, 0.62; 95% CI, 0.37-1.02; P = .06) and OS (median, 10.6 vs 8.1 months; HR, 0.75; 95% CI, 0.47-1.17; P = .21) were longer among those with ERBB mutation-positive disease than among those without. The presence of HER2 mutations was associated with favorable PFS and OS following afatinib vs erlotinib treatment. There was no apparent association between copy number alteration or EGFR expression level and outcome.

Conclusions and Relevance

Next-generation sequencing may help identify patients with lung squamous cell carcinoma who would derive additional benefit from treatment with afatinib. The role of ERBB mutations, particularly HER2 mutations, as predictive biomarkers for afatinib treatment in this setting warrants further evaluation.

Trial Registration

ClinicalTrials.gov Identifier: NCT01523587.

Prevalence and role of HER2 mutations in cancer

HER2 activating mutations act as oncogenic drivers in various cancer types. In the clinic, they can be identified by next generation sequencing (NGS) in either tumor biopsies or circulating cell-free DNA (cfDNA). Preclinical data indicate that HER2 "hot spot" mutations are constitutively active, have transforming capacity in vitro and in vivo and show variable sensitivity to anti-HER2 based therapies. Recent clinical trials also revealed activity of HER2-targeted drugs against a variety of tumors harboring HER2 mutations. Here, we review the prevalence and type of HER2 mutations identified in different human cancers, their biochemical and biological characterization, and their sensitivity to anti HER2-based therapies in both preclinical and clinical settings.

Clinical outcomes after whole-genome sequencing in patients with metastatic non-small-cell lung cancer

The Personalized Onco-Genomics (POG) program at BC Cancer integrates whole-genome (DNA) and RNA sequencing into practice for metastatic malignancies. We examined the subgroup of patients with metastatic non-small-cell lung cancer (NSCLC) and report the prevalence of actionable targets, treatments, and outcomes. We identified patients who were enrolled in the POG program between 2012 and 2016 who had a tumor biopsy and blood samples with comprehensive DNA (80×, 40× normal) and RNA sequencing followed by in-depth bioinformatics to identify potential cancer drivers and actionable targets. In NSCLC cases, we compared the progression-free survival (PFS) of "POG-informed therapies" with the PFS of the last regimen prior to POG (PFS ratio). In 29 NSCLC cases, 11 were male (38%), the median age was 60.2 yr (range: 39.4-72.6), and histologies included were adenocarcinoma (93%) and squamous cell carcinoma (7%). Potential molecular targets (i.e., cancer drivers including TP53 mutations) were identified in 26 (90%), and 21 (72%) had actionable targets. Therapies based on standard-of-care mutation analysis, such as EGFR mutations, were not considered POG-informed therapies. Thirteen received POG-informed therapies, of which three had no therapy before POG; therefore a comparator PFS could not be obtained. Of 10 patients with POG-informed therapy, median PFS ratio was 0.94 (IQR 0.2-3.4). Three (30%) had a PFS ratio ≥1.3, and three (30%) had a PFS ratio ≥0.8 and <1.3. In this small cohort of NSCLC, 30% demonstrated longer PFS with POG-informed therapies. Larger studies will help clarify the role of whole-genome analysis in clinical practice.

Afatinib as first-line treatment for advanced lung adenocarcinoma patients harboring HER2 mutation: A case report and review of the literature

HER2 mutations are a rare group of driving genes that respond to HER2 targeted therapy, particularly afatinib. No more than 20 such cases have been reported, but afatinib was used after first-line chemotherapy. We present the case of a never-smoking female patient diagnosed with stage IV lung adenocarcinoma harboring a Her2 exon 20 inserted mutation who achieved a durable response (12 months) to first-line afatinib treatment. We review the literature concerning afatinib therapy in this rare cohort of mutated lung cancer patients.

Risk Factors for Severe Diarrhea with an Afatinib Treatment of Non-Small Cell Lung Cancer: A Pooled Analysis of Clinical Trials

Afatinib is an effective therapy for metastatic non-small cell lung cancer (NSCLC) but it is associated with a relatively high incidence of severe diarrhea. The association between pre-treatment candidate predictors (age, sex, race, performance status, renal function, hemoglobin, and measures of body mass) and severe (grade ≥ 3) diarrhea was evaluated using logistic regression with pooled individual participant data from seven clinical studies. A risk score was developed based on the count of major risk factors. Overall, 184 of 1151 participants (16%) experienced severe diarrhea with use of afatinib. Body weight, body mass index, and body surface area all exhibited a prominent non-linear association where risk increased markedly at the lower range (p < 0.005). Low weight (<45 kg), female sex, and older age (≥60 years) were identified as major independent risk factors (p < 0.01). Each risk factor was associated with a two-fold increase in the odds of severe diarrhea, and this was consistent between individuals commenced on 40 mg or 50 mg afatinib. A simple risk score based on the count of these risk factors identifies individuals at lowest and highest risk (C-statistic of 0.65). Risk of severe diarrhea for individuals commenced on 40 mg afatinib ranged from 6% for individuals with no risk factors to 33% for individuals with all three risk factors.

Pneumonitis in advanced non-small-cell lung cancer patients treated with EGFR tyrosine kinase inhibitor: Meta-analysis of 153 cohorts with 15,713 patients: Meta-analysis of incidence and risk factors of EGFR-TKI pneumonitis in NSCLC

PURPOSE

Pneumonitis is a significant toxicity of EGFR tyrosine kinase inhibitors (EGFR-TKI) in non-small-cell lung cancer (NSCLC) patients. We studied the incidence of pneumonitis in clinical trials of EGFR-TKI published in 2003-2017, and performed subgroups analyses to identity predisposing factors.

METHODS

Ovid-MEDLINE and EMBASE search up to 4/17/17 using the keywords, "erlotinib", "gefitinib", "afatinib", "osimertinib", and "lung cancer", resulted in a total of 153 eligible trial cohorts with 15,713 advanced NSCLC patients treated with EGFR-TKI. The pooled incidence of all-grade, high-grade, and grade 5 pneumonitis was obtained. Subgroup analyses were performed with meta-regression using study-level covariates.

RESULTS

Among the patients without prior exposure to EGFR-TKI, the overall incidence was 1.12% (95% CI:0.79-1.58%) for all-grade, 0.61% (95% CI:0.40-0.93%) for high-grade, and 0.20% (95% CI:0.11-0.38%) for grade 5 pneumonitis. The incidence was significantly higher in Japanese studies compared to studies of non-Japan origin, for all-grade (4.77% vs. 0.55%, p < 0.001), high grade (2.49% vs. 0.37%, p < 0.001), and grade 5 pneumonitis (1.00% vs. 0.18%, p < 0.001). Multivariate analyses demonstrated higher odds of pneumonitis in Japanese studies for all-grade (odds ratio [OR]: 5.04; 95% CI:3.14-8.11, p < 0.001), high-grade (OR: 4.45; 95% CI:2.50-7.93, p < 0.001), and grade 5 pneumonitis (OR: 4.55; 95% CI:2.20-9.44, p < 0.001) compared to others, after adjusting for types of EGFR-TKI and lines of therapy. In patients with EGFR retreatment analyzed separately, the pooled incidence was 1.13% (95% CI:0.40-3.15%) for all-grade, 0.49% (95% CI:0.21-1.11%) for high-grade, and 0.16% (95% CI:0.04-0.65%) for grade 5 pneumonitis.

CONCLUSIONS

The overall incidence of EGFR-TKI pneumonitis was 1.12% in patients without prior exposure to EGFR-TKI, and 1.13% in EGFR-TKI retreatment group. The cohorts from Japan had significantly higher incidence of pneumonitis, providing insights for further mechanistic studies.

A systematic review of targeted agents for non-small cell lung cancer

BACKGROUND

advanced-stage non-small cell lung cancer (NSCLC) is characterized by having limited treatment options and thus a poor prognosis. However, new treatment options, in the form of targeted agents (TA), have emerged during recent years. This systematic review aims to provide an overview of the accessible literature in PubMed evaluating TA used on NSCLC patients, and the resulting survival outcomes.

METHOD

this systematic literature review was conducted by reviewing all relevant literature in PubMed. Six separate searches were performed: Three searches where controlled entry terms were used and three free text searches. Furthermore, other relevant publications were included manually. A total of seventy-two studies met the search criteria and were thus further analyzed and evaluated.

RESULTS

In the included studies, various TAs and their effect on different molecular targets have been evaluated. Clinical responses vary considerably among the different genetic aberrations. The majority of studies evaluated TA for epidermal growth factor receptor (EGFR) mutations and TA for echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) rearrangements. Studies regarding the use of TA for Rat sarcoma (RAS), rapidly accelerated fibrosarcoma (RAF), ROS proto-oncogene 1 (ROS1) rearrangement, Receptor tyrosine-protein kinase erbB-2 (ERBB2), Phosphatidylinositol 3-kinase (PIK3CA)/v-akt murine thymoma viral oncogene homolog; protein kinase B(AKT)/Phosphatase and tensin homolog deleted on chromosome 10(PTEN), The mammalian target of rapamycin (mTOR), and Mesenchymal-epithelial transition factor (MET) were included as well. In general, studies comparing treatment outcomes in EGFR-mutated patients and EML4-ALK (ALK) rearranged patients after use of either TA or standard chemotherapy, present significant better results after TA.

CONCLUSIONS

This systematic review provides an overview of available literature in PubMed regarding NSCLC and TA. Included studies point toward that TA appears to be a promising therapeutic tool in treating NSCLC patients and use of TA is expected to result in improved treatment outcomes.

Efficacy of Afatinib in a Previously-Treated Patient with Non-Small Cell Lung Cancer Harboring HER2 Mutation: Case Report

Human epidermal growth factor receptor 2 (HER2) mutation in non-small cell lung cancer (NSCLC) is an oncogenic driver that possibly becomes a druggable target to HER2-targeted therapy. The benefit of HER2-targeted therapy is much less defined especially in eastern populations. We provide evidence of clinical benefit of afatinib in a 50-year-old Asian woman with HER2-mutant NSCLC who previously failed cytotoxic chemotherapy and gefitinib treatment. Next-generation sequencing of the tumor tissue revealed a HER2 exon 20 mutation (c.2437A>G), which has never been reported. The patient was treated with afatinib for more than four months. She showed rapid radiologic response within a month, and maintained stable state until the last dose of afatinib.