Medical Treatment Options for Patients with Epidermal Growth Factor Receptor Mutation-Positive Non-Small Cell Lung Cancer Suffering from Brain Metastases and/or Leptomeningeal Disease

Does dose reduction of afatinib affect treatment outcomes of patients with EGFR-mutant metastatic non-small cell lung cancer in real-world clinical practice?

Background

Afatinib can be started at a dose lower than the recommended starting dose of 40 mg/day for the treatment of epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC), however treatment outcomes in real-world clinical practice remains unclear.

Methods

This retrospective study of patients with NSCLC from 18 major hospitals (public, private or university teaching hospitals) enrolled in Malaysia's National Cardiovascular and Thoracic Surgical Database (NCTSD) assessed the efficacy of lower doses of afatinib on treatment outcomes in a real-world clinical practice. Data on clinical characteristics, afatinib dosing, and treatment outcomes for patients included in NCTSD from 1st January 2015 to 31st December 2020 were analyzed.

Results

Of the 133 patients studied, 94.7% had adenocarcinoma. Majority of the patients (60.9%) had EGFR exon 19 deletion and 23.3% had EGFR exon 21 L858R point mutation. The mean age of patients was 64.1 years and majority (83.5%) had Eastern Cooperative Oncology Group performance status of 2-4 at diagnosis. The most common afatinib starting doses were 40 mg (37.6%), 30 mg (29.3%), and 20 mg (26.3%) once daily (OD), respectively. A quarter of patients had dose reduction (23.3%) due to side effects or cost constraints. Majority of the patients had partial response to afatinib (63.2%) whilst 2.3% had complete response. Interestingly, the objective response rate was significantly higher (72.3%) with afatinib OD doses of less than 40 mg compared to 40 mg (54.0%) (P=0.032). Patients on lower doses of afatinib were two times more likely to achieve an objective response [odds ratio =2.64; 95% confidence interval (CI): 1.20-5.83; P=0.016]. These patients had a numerically but not statistically longer median time to treatment failure (TTF). Median TTF (95% CI) for the overall cohort was 12.4 (10.02-14.78) months. Median overall survival (95% CI) was 21.30 (15.86-26.75) months.

Conclusions

Lower afatinib doses (<40 mg OD) could be equally effective as standard dose in patients with EGFR-mutant advanced NSCLC and may be more suited to Asian patients, minimizing side effects that may occur at higher dosages of afatinib leading to dose interruptions and affecting treatment outcomes.

Phase II trial of afatinib in patients with advanced urothelial carcinoma with genetic alterations in ERBB1-3 (LUX-Bladder 1)

BACKGROUND

Preclinical and early clinical data suggest that the irreversible ErbB family blocker afatinib may be effective in urothelial cancers harbouring ERBB mutations.

METHODS

This open-label, phase II, single-arm trial (LUX-Bladder 1, NCT02780687) assessed the efficacy and safety of second-line afatinib 40 mg/d in patients with metastatic urothelial carcinoma with ERBB1-3 alterations. The primary endpoint was 6-month progression-free survival rate (PFS6) (cohort A); other endpoints included ORR, PFS, OS, DCR and safety (cohorts A and B). Cohort A was planned to have two stages: stage 2 enrolment was based on observed antitumour activity.

RESULTS

Thirty-four patients were enroled into cohort A and eight into cohort B. In cohorts A/B, PFS6 was 11.8%/12.5%, ORR was 5.9%/12.5%, DCR was 50.0%/25.0%, median PFS was 9.8/7.8 weeks and median OS was 30.1/29.6 weeks. Three patients (two ERBB2-amplified [cohort A]; one EGFR-amplified [cohort B]) achieved partial responses. Stage 2 for cohort A did not proceed. All patients experienced adverse events (AEs), most commonly (any/grade 3) diarrhoea (76.2%/9.5%). Two patients (4.8%) discontinued due to AEs and one fatal AE was observed (acute coronary syndrome; not considered treatment-related).

CONCLUSIONS

An exploratory biomarker analysis suggested that basal-squamous tumours and ERBB2 amplification were associated with superior response to afatinib.

CLINICAL TRIAL REGISTRATION

NCT02780687.

A real-world study of Afatinib plus ramucirumab in treatment-naïve, EGFR-mutated, non-small cell lung cancer

BACKGROUND

Recent reports suggested combining ramucirumab with epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) to overcome EGFR resistance in non-small cell lung cancer (NSCLC). Nonetheless, evidence supporting the activity of afatinib and ramucirumab is lacking. This study investigated the survival benefits and safety profile of afatinib plus ramucirumab in patients with treatment-naïve, EGFR-mutated, metastatic NSCLC.

MATERIALS AND METHODS

The medical records of patients with EGFR-mutated NSCLC were retrospectively retrieved. Patients who received first-line sequential afatinib followed by ramucirumab and the first-line combination of afatinib plus ramucirumab were included. The Kaplan-Meier was used to estimate the progression-free survival (PFS) of all included patients, patients on sequential afatinib followed by ramucirumab (PFS1), and patients on the up-front combination of afatinib and ramucirumab (PFS2).

RESULTS

Thirty-three patients were included (25 women; median age: 63 [45-82] years). The median follow-up of the included patients was 17 months (range 6-89 months). the median PFS for the whole cohort was 71 months (95% CI 67.2-74.8) with eight events during the follow-up. The median PFS1 and PFS2 were 71 months (95 CI not defined) and 26 months (95% CI 18.6-33.4), respectively. In terms of OS, the median OS for all patients and patients on sequential treatment was not defined, while the median OS for patients on upfront combination was 30 months (95% CI 20.9-39.1). There was no significant association between EGFR mutation type and PFS1 or PFS2.

CONCLUSIONS

Afatinib plus ramucirumab could improve the PFS of patients with EGFR-positive NSCLC at a predictable safety profile. Our data also suggest a survival benefit of adding ramucirumab to afatinib in patients with uncommon mutations, which should be investigated further.

Leptomeningeal Metastasis from Non-Small Cell Lung Cancer and Current Landscape of Treatments

Leptomeningeal metastasis (LM), also known as leptomeningeal carcinomatosis (LC), is a devastating complication of metastatic cancer that occurs when neoplastic cells invade the meningeal space. Diagnosis of LM remains challenging given the heterogeneous signs and symptoms at presentation and requires thorough neurological examination, cerebrospinal fluid (CSF) analysis, and MRI of the brain and spine with gadolinium. Detecting neoplastic cells in the CSF is the gold standard for diagnosing leptomeningeal metastases; however, it has low sensitivity and may require multiple CSF samples. New emerging technologies, such as liquid biopsy of CSF, have increased sensitivity and specificity for detecting circulating tumor cells in CSF. The management of LM in patients with NSCLC requires an individualized multidisciplinary approach. Treatment options include surgery for ventricular shunt placement, radiation therapy to bulky or symptomatic disease sites, systemic or intrathecal chemotherapy, molecularly targeted agents, and, more recently, immunotherapy. Targeting actionable mutations in LM from NSCLC, such as EGFR tyrosine kinase inhibitors or anaplastic lymphoma kinase gene rearrangement inhibitors, has shown encouraging results in terms of disease control and survival. Although there are limited data regarding the use of immunotherapy in LM, immunotherapy has produced promising results in several case reports. In this review, we focused on the epidemiology, pathophysiology, clinical presentation, diagnosis, and current treatment strategies, with a special emphasis on novel agents, including targeted therapies and immunotherapy of LM in patients with NSCLC.

Novel Therapeutic Approaches in Neoplastic Meningitis

Central nervous system (CNS) metastasis from systemic cancers can involve the brain parenchyma, leptomeninges, or the dura. Neoplastic meningitis (NM), also known by different terms, including leptomeningeal carcinomatosis and carcinomatous meningitis, occurs due to solid tumors and hematologic malignancies and is associated with a poor prognosis. The current management paradigm entails a multimodal approach focused on palliation with surgery, radiation, and chemotherapy, which may be administered systemically or directly into the cerebrospinal fluid (CSF). This review focuses on novel therapeutic approaches, including targeted and immunotherapeutic agents under investigation, that have shown promise in NM arising from solid tumors.

Differences in actionable genomic alterations between brain metastases and non‑brain metastases in patients with non‑small cell lung cancer

Brain metastases (BM) have been closely associated with increased morbidity and poor survival outcomes in patients with non‑small cell lung cancer (NSCLC). Excluding risk factors in histological subtypes, genomic alterations, including epidermal growth factor receptor mutations and anaplastic lymphoma kinase (ALK) rearrangements have been also regarded as greater risk factors for BM in the aspect of molecular subtypes. In the present study, 69 tumor tissues and 51 peripheral blood samples from patients with NSCLC were analyzed using a hybridization capture‑based next‑generation sequencing (NGS) panel, including 95 known cancer genes. Among the 90 patients with stage IV NSCLC, 26 cases suffered from BM and 64 cases did not. In total, 174 somatic mutations in 35 mutated genes were identified, and 12 of these genes were concurrently present in the BM group and the non‑BM group. Importantly, five mutated genes including ALK, cytidine deaminase (CDA), SMAD family member 4 (SMAD4), superoxide dismutase 2 (SOD2) and Von Hippel‑Lindau tumor suppressor (VHL) genes were uniquely detected in the BM group, and they were enriched in the Hippo signaling pathway, pyrimidine metabolism and pantothenate and co‑enzyme A (CoA) biosynthesis, as demonstrated using Kyoto Encyclopedia of Genes and Genomes enrichment analysis. RNA polymerase II transcription regulator complex and promyelocytic leukemia nuclear body were the top functional categories according to the Gene Ontology enrichment analysis in the BM group and non‑BM group, respectively. Furthermore, 43.33% (13/30) of mutated genes were detected by both tumor tissue deoxyribonucleic acid (DNA) and plasma‑derived circulating tumor DNA (ctDNA) in the non‑BM group, while this percentage was only limited to 29.41% (5/17) in the BM group. To summarize, significant differences in somatic mutations, somatic interactions, key signaling pathways, functional biological information, and clinical actionability for the therapy of targeted agents were founded between the BM group and the non‑BM group, and ctDNA analysis may by applied as a more credible alternative for genomic profiling in patients with advanced NSCLC without BM, due to its higher consistency for genomic profiling between ctDNA analysis and tissue DNA analysis.

Sequential Afatinib and Osimertinib in Asian Patients with EGFR Mutation-Positive Non-Small Cell Lung Cancer and Acquired T790M: Combined Analysis of Two Global Non-Interventional Studies

Objective

Two recent non-interventional trials, GioTag and UpSwinG, demonstrated encouraging time-to-treatment failure (TTF) and overall survival (OS) in patients with epidermal growth factor receptor (EGFR) mutation-positive non-small cell lung cancer (NSCLC) (Del19 or L858R) who received sequential afatinib/osimertinib, especially in Asians. Here, we have undertaken a combined analysis of Asian patients from both studies.

Materials and Methods

Existing medical/electronic records were identified for consecutive EGFR-tyrosine kinase inhibitor (TKI)-naïve patients who received first-line afatinib/second-line osimertinib in “real-world” practice (all T790M-positive). Patients with active brain metastases were excluded. The primary objective was TTF. OS was a key secondary objective.

Results

One hundred and sixty-eight patients were analyzed. Most patients were recruited from South Korea or Japan (52/21%). At the start of afatinib, median age (range) was 61.5 years (35–88), 58% were female, Eastern Cooperative Oncology Group Performance Status (ECOG PS) (0/1/≥2) was 29/62/9%, 17% had brain metastases, and EGFR mutation status (Del19/L858R) was 65/35%. At the start of osimertinib, ECOG PS (0/1/≥2) was 22/61/17% and 14% had brain metastases. Median TTF and OS were 30.0 months (95% CI: 24.5–32.5) and 45.2 months (95% CI: 41.7–71.1), respectively. Median OS was 63.5 months in patients with a Del19 mutation. Median OS in patients with brain metastases or ECOG PS ≥2 was 26.4 and 33.1 months, respectively.

Conclusion

Sequential afatinib/osimertinib showed encouraging activity in Asian patients with EGFR mutation-positive NSCLC and T790M-mediated acquired resistance, especially those with Del19-positive disease. Activity was observed across “real-world” patients including those with poor ECOG PS and/or brain metastases. ECOG PS and incidence of brain metastases remained stable prior to, and after, afatinib.

The multi-kinase inhibitor afatinib serves as a novel candidate for the treatment of human uveal melanoma

PURPOSE

Uveal melanoma (UM) is the most common intraocular malignancy in adults with a poor prognosis and a high recurrence rate. Currently there is no effective treatment for UM. Multi-kinase inhibitors targeting dysregulated pro-tumorigenic signalling pathways have revolutionised anti-cancer treatment but, as yet, their efficacy in UM has not been established. Here, we identified the multi-kinase inhibitor afatinib as a highly effective agent that exerts anti-UM effects in in vitro, ex vivo and in vivo models.

METHODS

We assessed the anti-cancer effects of afatinib using cell viability, cell death and cell cycle assays in in vitro and ex vivo UM models. The signaling pathways involved in the anti-UM effects of afatinib were evaluated by Western blotting. The in vivo activity of afatinib was evaluated in UM xenograft models using tumour mass measurement, PET scan, immunohistochemical staining and TUNEL assays.

RESULTS

We found that afatinib reduced cell viability and activated apoptosis and cell cycle arrest in multiple established UM cell lines and in patient tumour-derived primary cell lines. Afatinib impaired cell migration and enhanced reproductive death in these UM cell models. Afatinib-induced cell death was accompanied by activation of STAT1 expression and downregulation of Bcl-xL and cyclin D1 expression, which control cell survival and cell cycle progression. Afatinib attenuated HER2-AKT/ERK/PI3K signalling in UM cell lines. Consistent with these observations, we found that afatinib suppressed tumour growth in UM xenografted mice.

CONCLUSION

Our data indicate that afatinib activates UM cell death and targets the HER2-mediated cascade, which modulates STAT1-Bcl-xL/cyclin D1 signalling. Thus, targeting HER2 with agents like afatinib may be a novel therapeutic strategy to treat UM and to prevent metastasis.

Safety and efficacy of combining afatinib and whole-brain radiation therapy in treating brain metastases from EGFR-mutated NSCLC: a case report and literature review

Combining EGFR-tyrosine kinase inhibitors (TKIs) to whole brain radiation therapy (WBRT) has been shown to be more effective than EGFR-TKIs or WBRT alone in treating brain metastases (BMs) from EGFR-mutated Non Small-Cell Lung Cancer (NSCLC). However, despite the combination results well tolerated, EGFR-TKIs are often discontinued before WBRT, to reduce the risk of possible side effects, potentially resulting in reduced treatment efficacy and possible progression of intra- and extra-cranial disease. Afatinib, an irreversible inhibitor of EGFR-TK, has been shown to radiosensitize NSCLC in pre-clinical models and, compared to the other EGFR-TKIs, more efficiently penetrates the blood-brain barrier. However, nowadays, only two case reports describe the therapeutic efficiency and safety of combining afatinib with WBRT. Herein, we report on a 58-year-old woman patient with symptomatic BMs from NSLCL, treated with afatinib and concomitant WBRT, 30 Gy in 10 fractions. Treatment induced a remarkable and persistent radiological regression of BMs and the disappearance of neurological symptoms. However, the patient experienced severe skin toxicity of G3, corresponding to the irradiation area. Toxicity was successfully treated pharmacologically, and the patient did not experience any BMs-related symptoms for the next 10 months. She died of COVID-19-related respiratory failure. The association of afatinib with WBRT appears to be a successful strategy in the control of BMs from EGFR-mutated NSCLC. However, it should be considered that the combination could be responsible for serious dermatological toxicity.

Genomic Analysis of Tumors from Patients with Glioblastoma with Long-Term Response to Afatinib

Glioblastoma is an aggressive form of central nervous system tumor. Recurrence rates following primary therapy are high, and few second-line treatment options provide durable clinical benefit. Aberrations of the epidermal growth factor receptor (EGFR) gene are observed in up to 57% of glioblastoma cases and EGFR overexpression has been identified in approximately 60% of primary glioblastomas. In preclinical studies, afatinib, a second-generation ErbB blocker, inhibited cell proliferation in cells harboring mutations commonly found in glioblastoma. In two previous Phase I/II studies of afatinib plus temozolomide in patients with glioblastoma, limited efficacy was observed; however, there was notable benefit in patients with the EGFR variant III (EGFRvIII) mutation, EGFR amplification, and those with loss of phosphatase and tensin homolog (PTEN). This case series report details treatment histories of three long-term responders from these trials. Next-generation sequencing of tumor samples identified alterations in a number of cancer-related genes, including mutations in, and amplification of, EGFR. Tumor samples from all three patients shared favorable prognostic factors, eg O⁶-methylguanine-DNA methyl-transferase (MGMT) gene promoter methylation; however, negative prognostic factors were also observed, suggesting that these shared genetic features did not completely account for the favorable responses. The genetic profile of the tumor from Patient 1 showed clear differences from the other two tumors: lack of involvement of EGFR aberrations but with a mutation occurring in PTPN11. Preclinical studies showed that single-agent afatinib and temozolomide both separately inhibit the growth of tumors with a C-terminal EGFR truncation, thus providing further rationale for combining these two agents in the treatment of glioblastomas harboring EGFR aberrations. These findings suggest that afatinib may provide treatment benefit in patients with glioblastomas that harbor ErbB family aberrations and, potentially, other genetic aberrations. Further studies are needed to establish which patients with newly diagnosed/recurrent glioblastomas may potentially benefit from treatment with afatinib.

Targeting tumor endothelial hyperglycolysis enhances immunotherapy through remodeling tumor microenvironment

Vascular abnormality is a hallmark of most solid tumors and facilitates immune evasion. Targeting the abnormal metabolism of tumor endothelial cells (TECs) may provide an opportunity to improve the outcome of immunotherapy. Here, in comparison to vascular endothelial cells from adjacent peritumoral tissues in patients with colorectal cancer (CRC), TECs presented enhanced glycolysis with higher glyceraldehyde-3-phosphate dehydrogenase (GAPDH) expression. Then an unbiased screening identified that osimertinib could modify the GAPDH and thus inhibit its activity in TECs. Low-dose osimertinib treatment caused tumor regression with vascular normalization and increased infiltration of immune effector cells in tumor, which was due to the reduced secretion of lactate from TECs by osimertinib through the inhibition of GAPDH. Moreover, osimertinib and anti-PD-1 blockade synergistically retarded tumor growth. This study provides a potential strategy to enhance immunotherapy by targeting the abnormal metabolism of TECs.

The Tumor Control According to Radiation Dose of Gamma Knife Radiosurgery for Small and Medium-Sized Brain Metastases from Non-Small Cell Lung Cancer

Objective

The effectiveness of gamma knife radiosurgery (GKR) in the treatment of brain metastases is well established. The aim of this study was to evaluate the efficacy and safety of maximizing the radiation dose in GKR and the factors influencing tumor control in cases of small and medium-sized brain metastases from non-small cell lung cancer (NSCLC).

Methods

We analyzed 230 metastatic brain tumors less than 5 mL in volume in 146 patients with NSCLC who underwent GKR. The patients had no previous radiation therapy for brain metastases. The pathologies of the tumors were adenocarcinoma (n=207), squamous cell carcinoma (n=18), and others (n=5). The radiation doses were classified as 18, 20, 22, and 24 Gy, and based on the tumor volume, the tumors were categorized as follows : small-sized (less than 1 mL) and medium-sized (1–3 and 3–5 mL). The progression-free survival (PFS) of the individual 230 tumors and 146 brain metastases was evaluated after GKR depending on the pathology, Eastern Cooperative Oncology Group (ECOG) performance score (PS), tumor volume, radiation dose, and anti-cancer regimens. The radiotoxicity after GKR was also evaluated.

Results

After GKR, the restricted mean PFS of individual 230 tumors at 24 months was 15.6 months (14.0–17.1). In small-sized tumors, as the dose of radiation increased, the tumor control rates tended to increase (p=0.072). In medium-sized tumors, there was no statistically difference in PFS with an increase of radiation dose (p=0.783). On univariate analyses, a statistically significant increase in PFS was associated with adenocarcinomas (p=0.001), tumors with ECOG PS 0 (p=0.005), small-sized tumors (p=0.003), radiation dose of 24 Gy (p=0.014), synchronous lesions (p=0.002), and targeted therapy (p=0.004). On multivariate analyses, an improved PFS was seen with targeted therapy (hazard ratio, 0.356; 95% confidence interval, 0.150–0.842; p=0.019). After GKR, the restricted mean PFS of brain at 24 months was 9.8 months (8.5–11.1) in 146 patients, and the pattern of recurrence was mostly distant within the brain (66.4%). The small and medium-sized tumors treated with GKR showed radiotoxicitiy in five out of 230 tumors (2.2%), which were controlled with medical treatment.

Conclusion

The small-sized tumors were effectively controlled without symptomatic radiation necrosis as the radiation dose was increased up to 24 Gy. The medium-sized tumors showed potential for symptomatic radiation necrosis without signifcant tumor control rate, when greater than 18 Gy. GKR combined targeted therapy improved the tumor control of GKR-treated tumors.

An open-label expanded access program of afatinib in EGFR tyrosine kinase inhibitor-naïve patients with locally advanced or metastatic non-small cell lung cancer harboring EGFR mutations

BACKGROUND

Afatinib is approved globally for EGFR-TKI treatment-naïve patients with EGFR mutation-positive non-small cell lung cancer (NSCLC). In this Korean expanded access program, we evaluated its 'real-world' safety and efficacy.

METHODS

EGFR-TKI treatment-naïve patients with EGFR mutation-positive NSCLC received afatinib 40 mg/day until disease progression or other withdrawal criteria. Dose reductions were permitted for adverse events (AEs). The primary endpoint was the number of patients with AEs (CTCAE version 3.0). Other endpoints included progression-free survival (PFS), overall response rate (ORR), duration of response (DOR), and changes in investigator-assessed cancer-related symptoms.

RESULTS

Eighty-eight patients received afatinib, including 27 (31%) with brain metastases and 16 (18%) with uncommon EGFR mutations. Median PFS was 17.0 months (95% confidence interval [CI] 12.9-23.3 months). Grade 3 treatment-related AEs (TRAEs) were reported in 51 (58%) patients; the most common were diarrhea (22%) and rash/acne (20%). No grade > 3 TRAEs were reported. AEs leading to dose reduction occurred in 49 (56%) patients. Treatment discontinuation due to TRAEs occurred in 4 (5%) patients. ORR was 81% overall, 89% in patients with brain metastases, and 55% in patients with uncommon mutations (excluding T790M/exon 20 insertions). Median DOR was 15.1 months (95% CI 12.4-21.4 months). Cancer-related symptoms were improved/unchanged/worsened in 34-66%/36-66%/0-3% of patients over the first year.

CONCLUSIONS

No unexpected safety signals for afatinib were observed. AEs were manageable; the treatment discontinuation rate was low. Afatinib showed encouraging efficacy in a broad patient population including those with brain metastases or tumors harboring uncommon EGFR mutations.

TRIALS REGISTRATION

ClinicalTrials.gov NCT01931306 ; 29/08/2013.

Identification of optimal dosing schedules of dacomitinib and osimertinib for a phase I/II trial in advanced EGFR-mutant non-small cell lung cancer

Despite the clinical success of the third-generation EGFR inhibitor osimertinib as a first-line treatment of EGFR-mutant non-small cell lung cancer (NSCLC), resistance arises due to the acquisition of EGFR second-site mutations and other mechanisms, which necessitates alternative therapies. Dacomitinib, a pan-HER inhibitor, is approved for first-line treatment and results in different acquired EGFR mutations than osimertinib that mediate on-target resistance. A combination of osimertinib and dacomitinib could therefore induce more durable responses by preventing the emergence of resistance. Here we present an integrated computational modeling and experimental approach to identify an optimal dosing schedule for osimertinib and dacomitinib combination therapy. We developed a predictive model that encompasses tumor heterogeneity and inter-subject pharmacokinetic variability to predict tumor evolution under different dosing schedules, parameterized using in vitro dose-response data. This model was validated using cell line data and used to identify an optimal combination dosing schedule. Our schedule was subsequently confirmed tolerable in an ongoing dose-escalation phase I clinical trial (NCT03810807), with some dose modifications, demonstrating that our rational modeling approach can be used to identify appropriate dosing for combination therapy in the clinical setting.

Factors affecting treatment selection and overall survival for first-line EGFR-tyrosine kinase inhibitor therapy in non-small-cell lung cancer

Aim: To investigate the factors associated with treatment selection and overall survival for first-line EGFR-tyrosine kinase inhibitors (EGFR-TKIs) therapy among patients with non-small-cell lung cancer. Materials & methods: We conducted a retrospective cohort study of linked administrative health databases in Ontario, Canada. Results: A total of 1011 patients received an EGFR-TKI as first-line therapy. Treatment selection and overall survival associated with these treatments were affected by age, sex, geographical residency, comorbidities and different sites of metastasis. Conclusion: Though recent approval of osimertinib offers a potential new standard of care in the first-line setting, earlier generation TKIs remain pillars in treatment of non-small-cell lung cancer therapeutic armamentarium. Our findings may contribute to optimizing treatment sequencing of EGFR-TKIs to maximize clinical benefits.

A Comparison Between First-, Second- and Third-Generation Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors in Patients with Non-Small-Cell Lung Cancer and Brain Metastases

Patients with non-small-cell lung cancer (NSCLC), harboring Epidermal Growth Factor Receptor (EGFR) mutations, are more susceptible to brain metastases (BM). Comparisons of the efficacy of different-generation EGFR-tyrosine kinase inhibitors (TKI) on BMs from NSCLC are currently limited. We identified studies comparing different EGFR-TKIs for NSCLC through Pubmed literature search and selected those with neurological outcome data. By two retrospective analyses, Erlotinib showed longer neurological time-to-progression (30 months vs. 15.8 months, P = 0.024) and reduced the risk of central nervous system (CNS) progression (Hazard Ratio (HR) 0.25; 95% CI, 0.08–0.81; P = 0.021) compared to Gefitinib. In a phase 2b randomized trial, 16% of patients with BMs had a similar Progression Free Survival (PFS) (HR 0.76, 95% CI 0.41–1.44) or Overall Survival (OS) (HR 1.16, 95% CI 0.61–2.21) with Afatinib versus Gefitinib; a lower risk of developing subsequent BMs with Afatinib than Gefitinib (HR 0.49; 95% CI 0.34–0.71; P < 0.001) was reported by a retrospective study. A randomized phase 3 trial proved that patients with BMs treated with Osimertinib had longer PFS (HR 0.47, 95% CI 0.30–0.74) and OS (HR 0.79, 95% CI 0.61–1.01) than with Gefitinib, and lower incidence of CNS progression (6% vs. 15%, respectively). Although there is limited evidence, differences in CNS activity may exist between EGFR-TKIs.

Orally effective FDA-approved protein kinase targeted covalent inhibitors (TCIs)

Because dysregulation of protein kinases owing to mutations or overexpression plays causal roles in human diseases, this family of enzymes has become one of the most important drug targets of the 21st century. Of the 62 protein kinases inhibitors that are approved by the FDA, seven of them form irreversible covalent adducts with their target enzymes. The clinical success of ibrutinib, an inhibitor of Bruton tyrosine kinase, in the treatment of mantle cell lymphomas following its approval in 2013 helped to overcome a general bias against the development of irreversible drug inhibitors. The other approved covalent drugs include acalabrutinib and zanubrutinib, which also inhibit Bruton tyrosine kinase. Furthermore afatinib, dacomitinib, and osimertinib, inhibitors of members of the epidermal growth factor receptor family (ErbB1/2/3/4), are used in the treatment of non-small cell lung cancers. Neratinib is an inhibitor of ErbB2 and is used in the treatment of ErbB2/HER2-positive breast cancer. The seven drugs considered in this review have a common mechanism of action; this process involves the addition of a protein cysteine thiolate anion (protein‒S:^-) to an acrylamide derivative (CH₂=CHC(=O)N(H)R) where R represents the pharmacophore. Such reactions are commonly referred to as Michael additions and each reaction results in the formation of a covalent bond between carbon and sulfur; the final product is a thioether. This process consists of two discrete steps; the first step involves the reversible association of the drug with its target enzyme so that a weakly electrophilic functionality, a warhead, is bound near an appropriately positioned nucleophilic cysteine. In the second step, a reaction occurs between the warhead and the target enzyme cysteine to form a covalently modified and inactive protein. For this process to work, the warhead must be appropriately juxtaposed in relationship to the cysteinyl thiolate so that the covalent addition can occur. Covalent inhibitors have emerged from the ranks of drugs to be avoided to become an emerging paradigm. Much of this recent success can be attributed to the clinical efficacy of ibrutinib as well as the other antagonists covered in this review. Moreover, the covalent inhibitor methodology is swiftly gaining acceptance as a valuable component of the medicinal chemist's toolbox and is primed to make a significant impact on the development of enzyme antagonists and receptor modulators.

Proteomic Reveals Reasons for Acquired Drug Resistance in Lung Cancer Derived Brain Metastasis Based on a Newly Established Multi-Organ Microfluidic Chip Model

Anti-tumor drugs can effectively shrink the lesions of primary lung cancer; however, it has limited therapeutic effect on patients with brain metastasis (BM). A BM preclinical model based on a multi-organ microfluidic chip has been established proficiently in our previous work. In this study, the BM subpopulation (PC9-Br) derived from the parental PC9 cell line was isolated from the chip model and found to develop obvious resistance to antineoplastic drugs including chemotherapeutic agents (cisplatin, carboplatin, pemetrexed) and tyrosine kinase inhibitors (TKIs) which target epidermal growth factor receptor (EGFR); this suggested that the acquisition of drug-resistance by brain metastatic cells was attributable to the intrinsic changes in PC9-Br. Hence, we performed proteomic and revealed a greatly altered spectrum of BM protein expression compared with primary lung cancer cells. We identified the hyperactive glutathione (GSH) metabolism pathway with the overexpression of various GSH metabolism-related enzymes (GPX4, RRM2, GCLC, GPX1, GSTM4, GSTM1). Aldehyde dehydrogenases (ALDH1A1, ALDH3A1) were also found to be upregulated in BM. What's more, loss of EGFR and phosphorylated EGFR in PC9-Br gave reasons for the TKIs resistance. Collectively, our findings indicated potential mechanisms for the acquirement of drug resistance occurred in BM, providing new strategies to overcome therapeutic resistance in lung cancer BM.

Osimertinib combined with bevacizumab for leptomeningeal metastasis from EGFR-mutation non-small cell lung cancer: A phase II single-arm prospective clinical trial

Background

Leptomeningeal metastasis (LM) is associated with poor prognosis in non‐small cell lung cancer (NSCLC). The aim of this study was to investigate the efficacy and safety of osimertinib combined with bevacizumab for LM from epidermal growth factor receptor mutation (EGFRm) NSCLC.

Methods

We conducted a phase II single‐arm prospective clinical trial of EGFRm NSCLC with LM treated with osimertinib combined with bevacizumab. LM response assessment was based on the modified RANO LM radiological criteria; CNS and extra‐CNS response was evaluated according to the Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. The primary end points included LM progression‐free survival (PFS) and objective response rate (ORR); the secondary end points included safety and LM overall survival (OS).

Results

A total of 14 patients were included in the study, with a median age of 61 years, and they were predominantly female (64%). EGFR mutations were reported in exons 19 del (n = 7) and 21 L858R (n = 7). When LM was diagnosed, 12 (85.7%) patients had clinical symptoms, 71.4% (10/14) of patients were diagnosed with LM by cytology, and five (35.7%) patients had a performance status (PS) score > 2. The median LM PFS was 9.3 months (95% CI: 8.2–10.4), and the LM ORR was 50%. The safety findings in the present study were consistent with the known profile of osimertinib with bevacizumab; the median LM OS was 12.6 months, and the one‐year survival rate was 35.7%.

Conclusions

Osimertinib combined with bevacizumab is an appropriate treatment option for patients with LM from EGFRm NSCLC.

Key points

Significant findings of the study

To date, there is no prospective clinical study on the treatment of osimertinib combined with bevacizumab in EGFRm NSCLC with LM.

What this study adds

The median LM PFS was 9.3 months (95% CI: 8.2–10.4), and the LM ORR was 50%, the median LM OS was 12.6 months, and the one‐year survival rate was 35.7%. Osimertinib combined with bevacizumab is an appropriate treatment option for patients with LM from EGFRm NSCLC.

Network meta-analyses for EGFR mutation-positive non-small-cell lung cancer: systematic review and overview of methods and shortcomings

Aim: To perform a review of network meta-analyses (NMAs) for the first-line treatment of EGFR mutation-positive non-small-cell lung cancer, and to provide an overview of methodological approaches and potential shortcomings. Materials & methods: We conducted a systematic review of NMAs and evaluated their methodologies, including inclusion/exclusion criteria, information sources, results and outcomes, and statistical methodologies. Results: We identified ten published NMAs using five archetypical network structures. Despite similar objectives, there was substantial variability in the number of trials included in each NMA and in the relative treatment efficacy of the tyrosine kinase inhibitors. Conclusion: We identified methodological issues to explain differences in the findings, criteria for inclusion in NMAs and the degree of lumping of treatments. These factors should be given particular consideration in future research.

Optimizing therapy sequence to prevent patient attrition in EGFR mutation-positive advanced or metastatic NSCLC

Clinical trial and real-world data in non-small-cell lung cancer indicate that 10-60% of patients that progressed on first- or second-generation EGFR-targeting tyrosine kinase inhibitors (TKI) do not receive systemic second-line therapy. In our article, we discuss efficacy, safety and treatment duration with different EGFR-TKIs and stress the need for delivery of the most efficacious therapy in the first-line. We also provide our perspective on analysis of circulating tumor DNA and the role of EGFR-TKI in combined therapies. Finally, we review new therapeutic options to overcome resistance to EGFR-TKI. We believe that overall treatment duration and access to different medications in subsequent lines of therapy should be considered when planning the optimal treatment strategy.

Emerging treatment strategies for breast cancer brain metastasis: from translational therapeutics to real-world experience

Systemic therapies for primary breast cancer have made great progress over the past two decades. However, oncologists confront an insidious and particularly difficult problem: in those patients with metastatic breast cancer, up to 50% of human epidermal growth factor 2 (HER2)-positive and 25-40% of triple-negative subtypes, brain metastases (BM) kill most of them. Fortunately, standard- of-care treatments for BM have improved rapidly, with a decline in whole brain radiation therapy and use of fractionated stereotactic radiosurgery as well as targeted therapies and immunotherapies. Meanwhile, advances in fundamental understanding of the basic biological processes of breast cancer BM (BCBM) have led to many novel experimental therapeutic strategies. In this review, we describe the most recent clinical treatment options and emerging experimental therapeutic strategies that have the potential to combat BCBM.

Safety and CSF distribution of high-dose erlotinib and gefitinib in patients of non-small cell lung cancer (NSCLC) with brain metastases

PURPOSE

Patients of non-small cell lung cancer (NSCLC) with brain metastases have limited treatment options. High-dose erlotinib (HDE) and gefitinib (HDG) have been tried in the past. This study investigates the cerebrospinal fluid (CSF) disposition and safety of both, high-dose erlotinib and gefitinib regimens.

METHODS

Eleven and nine patients were treated with erlotinib and gefitinib, respectively. All patients received 1 week of standard dose of erlotinib (150 mg OD) or gefitinib (250 mg OD), followed by the high dose (1500 mg weekly for erlotinib and 1250 mg OD for gefitinib) from day 8. Blood and CSF samples were collected on days 7 and 15, 4 h after the morning dose and drug levels determined using LC-MS/MS. Adverse events were documented as per CTCAE 4.03 till day 15.

RESULTS

Pulsatile HDE and daily HDG resulted in 1.4- and 1.9-fold increase in CSF levels, respectively. A constant 2% CSF penetration rate was observed across both doses of erlotinib, while for gefitinib the penetration rate for high dose was half that of the standard dose suggesting a nonlinear disposition. Three patients on HDE treatment discontinued treatment after the first dose due to intolerable toxicities, whereas HDG was better tolerated with no treatment discontinuations. Since CSF disposition of gefitinib followed saturable kinetics, a lower dose of 750 mg was found to achieve CSF concentrations comparable to that of the 1250 mg dose.

CONCLUSIONS

HDG was better tolerated than HDE. CSF disposition of gefitinib was found to be saturable at a higher dose. Based on these findings, the dose of 750 mg OD should be considered for further evaluation in this setting.

A study on different therapies and prognosis-related factors for brain metastases in lung adenocarcinoma patients with driver mutation

Brain metastases (BMs) are frequently occurred in lung adenocarcinoma with driver mutation. There is a need to explore multi-discipline treatments and prognostic factors in those patients with most frequent driver mutations: EGFR mutation and ALK fusion. In the retrospective study, different therapies and prognostic factors were compared between EGFR and ALK-driven lung adenocarcinoma with BMs. 516 patients with EGFR mutation and 76 with ALK fusion were screened for this study, 303 (58.7%) and 34 (44.7%) had BM respectively. In multivariate analyses, the pretreatment factors including delayed BMs and asymptomatic BMs, treatment strategies including the first-generation tyrosine kinase inhibitor (TKI) and cranial radiotherapy (RT) treatment, were associated with much better OS in EGFR mutation patients. Moreover, we found EGFR-mutation patients receiving erlotinib would achieve better survival than those receiving gefitinib (P = 0.032). However, BM patients with ALK fusion treated by only the first generation TKI (HR = 0.23, P = 0.036) or cranial RT (HR = 0.12, P = 0.003), had better OS. After balancing of baseline characteristics of the two groups, there was no significant difference in the survival between BM patients with EGFR mutation and ALK fusion. And only cranial RT was associated with better survival in those patients (HR = 0.52, P < 0.001). In the BM patients of lung adenocarcinoma with driver mutation, TKI underlie the therapy strategies, but cranial RT still plays an important role while receiving the first generation TKI.

Strategies to prevent brain metastasis

PURPOSE OF REVIEW

The current article reviews the state of art of prevention strategies for brain metastases from solid tumors and touches both old pivotal studies and new directions of personalized molecular approaches.

RECENT FINDINGS

Prophylactic cranial irradiation (PCI) has a definite role in the prevention of relapse into the brain for patients with small cell lung cancer (SCLC) responding to chemotherapy and radiotherapy as it prolongs overall survival (OS). However, the risk of late cognitive deficit following whole brain radiotherapy (WBRT) in this patient population is still not well known. Conversely, PCI significantly reduces the incidence of brain metastases and prolongs the disease-free interval in patients with non-SCLC (NSCLC), but does not improve OS thus far. Pharmacologic prevention is a new concept driven by the efficacy of targeted agents on macrometastases from specific molecular subgroups.

SUMMARY

The future challenges for prevention of brain metastases are represented by the identification of subgroups of patients at higher risk of relapse into the brain coupled with either new WBRT strategies to better preserve cognition or effective molecular agents to target micrometastases.

Is there a role for dacomitinib, a second-generation irreversible inhibitor of the epidermal-growth factor receptor tyrosine kinase, in advanced non-small cell lung cancer?

INTRODUCTION

Non-small cell lung cancer (NSCLC) is a highly lethal disease. During the past 20 years, the epidermal growth factor receptor (EGFR) has been a relevant target for anticancer drug-design, and a large family of EGFR tyrosine kinase inhibitors (TKI) were designed, which improved therapeutic outcomes compared to conventional chemotherapy in NSCLC patients with specific EGFR mutations. However, resistance to these inhibitors occurs; therefore, the debate on which inhibitor should be used first is still open. Dacomitinib was approved in 2018 for the first-line treatment of NSCLC with EGFR activating mutations.

AREAS COVERED

This manuscript reviews the properties of dacomitinib, including the current information from clinical trials and its potential application as stand-alone therapy, or in combination.

EXPERT OPINION

Dacomitinib is a second-generation EGFR-TKI that has demonstrated significant improvement in overall survival in a phase III randomized study compared with gefitinib, a first-generation TKI. However, the rapid development and approval of a new generation of TKIs (osimertinib), with better clinical profiles, raises the question of which role can dacomitinib play in NSCLC. Further studies are required to evaluate the efficacy of this drug on brain metastases, as a second-line treatment after third-generation TKIs, or in combination with other types of treatments.

Four generations of EGFR TKIs associated with different pathogenic mutations in non-small cell lung carcinoma

Non-small cell lung carcinoma (NSCLC) is a malignant tumour with poor prognosis and high mortality. Platinum-based dual-agent chemotherapy is the main therapeutic regimen for this disease. In recent years, because of the introduction of molecular targeted therapy, various targeted therapeutic agents against epidermal growth factor receptor (EGFR) have been rapidly developed, which has become a research hotspot for NSCLC treatment. Here, we review the latest studies describing the features and types of EGFR pathogenic mutations, currently established EGFR-tyrosine kinase inhibitors from the first to fourth generation, including their action mechanisms, acquired resistance, and clinical applications, and potential challenges and perspectives that current researchers should address.

Leptomeningeal metastasis from solid tumors

Central nervous system (CNS) metastasis from systemic cancers can involve the brain parenchyma, leptomeninges (pia, subarachnoid space and arachnoid mater), and dura. Leptomeningeal metastases (LM), also known by different terms including neoplastic meningitis and carcinomatous meningitis, occur in both solid tumors and hematologic malignancies. This review will focus exclusively on LM arising from solid tumors with a goal of providing the reader an understanding of the epidemiology, pathophysiology, clinical presentation, prognostication, current management and future directions.

Tyrosine Kinase Inhibitors for the Treatment of EGFR Mutation-Positive Non-Small-Cell Lung Cancer: A Clash of the Generations

The availability of 3 generations of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) with different pharmacologic characteristics and clinical profiles has provided oncologists with a potentially confusing choice for the treatment of EGFR mutation-positive non-small-cell lung cancer. Although recent head-to-head clinical trials have demonstrated improved efficacy with second-generation (ie, afatinib, dacomitinib) and third-generation (ie, osimertinib) TKIs compared with the first-generation TKIs (eg, erlotinib, gefitinib), acquired resistance has been inevitable, regardless of which agent has been chosen as first-line therapy. Thus, the potential availability of subsequent treatment options is an important consideration. Recent data have demonstrated that osimertinib confers an overall survival benefit compared with first-generation EGFR TKIs, and dacomitinib has shown an overall survival benefit compared with gefitinib in an exploratory analysis. However, the relative benefits of different sequential EGFR-TKI regimens, especially those involving second- and third-generation agents, have remained uncertain and require prospective evaluation. Few such data currently exist to inform treatment choices. In the present review, we examined the pharmacologic characteristics and current clinical data for EGFR TKIs, including emerging information on the molecular mechanisms of resistance across the different generations of TKIs. Given the uncertainties regarding the optimal treatment choice, we have focused on the factors that might help determine the treatment decisions, such as efficacy and safety in patient subgroups. We also discussed the emerging real-world data, which have provided some insights into the benefits of sequential regimens in everyday clinical practice.

Osimertinib 160 mg daily for advanced non-small cell lung cancer with leptomeningeal metastasis: A case report

Advanced non-small cell lung cancer (NSCLC) with leptomeningeal metastases (LM) is associated with a dismal prognosis of typically 3-9 months. In preclinical and clinical studies, the third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor osimertinib has demonstrated activity in the central nervous system (CNS), and studies are ongoing. We report here a case of osimertinib used at 160 mg once daily in a heavily pretreated patient with EGFR exon 20 T790M-negative advanced NSCLC with LM to achieve a partial response, including shrinkage of the LM, for up to 12 months until further progression. The case suggests the feasibility of using osimertinib at a twofold standard dose to treat CNS metastases, irrespective of the T790M mutation status.

Response of Leptomeningeal Metastases in EGFR-Mutated Non-Small-Cell Lung Cancer to Afatinib in the Absence of Radiotherapy

Palliative radiotherapy is currently the medical standard of care for non-small-cell lung cancer (NSCLC) patients with symptomatic CNS and leptomeningeal disease. We report the case of a 62-year-old male patient with EGFR mutation (del19+) NSLC with symptomatic lymph node, bone, CNS, and leptomeningeal metastases. Taking into account on one hand the response to tyrosine kinase inhibitors (TKIs) and on the other hand the short- to medium-term side effects of radiotherapy and the lack of timely availability in our healthcare system, the patient was treated with afatinib (40 mg daily) and exhibited a rapid response with improvement of neurological symptoms. The patient presented partial response of extracranial, CNS, and leptomeningeal lesions at 3, 6, and 12 months of treatment, currently completing 16 months of progression-free survival despite presenting mild dermatological and gastrointestinal toxicities. Afatinib is an effective and safe option in patients with NSLC EGFR mutation del19+ with CNS and leptomeningeal compromise avoiding or delaying radiotherapy and its side effects, especially in countries where there is a lack of access to this kind of therapy.

Efficacy of Osimertinib in EGFR-Mutated Non-Small Cell Lung Cancer with Leptomeningeal Metastases Pretreated with EGFR-Tyrosine Kinase Inhibitors

BACKGROUND

The prognosis of patients with non-small cell lung cancer (NSCLC) who develop leptomeningeal metastasis (LM) is poor.

OBJECTIVE

To assess the clinical efficacy of osimertinib, a third-generation tyrosine-kinase inhibitor (TKI), in patients with epidermal growth-factor receptor (EGFR)-mutated NSCLCs and LM.

PATIENTS AND METHODS

Retrospective study of NSCLC patients with osimertinib-treated EGFR-mutated NSCLC and LM.

RESULTS

Twenty patients (mean age, 61.2 years; 70% women) with adenocarcinoma NSCLC were included in the study. EGFR mutations were reported in exons 18 (n = 2), 19 (n = 7), and 21 (n = 11). Before starting osimertinib, patients had received a mean of 2.3 treatment lines. When LM was diagnosed, all patients had clinical symptoms. Sixteen (80%) patients had a performance status ≥2. At osimertinib initiation, 13 (65%) patients harbored the EGFR-T790M-resistance mutation. Osimertinib was started at 80 (n = 17), 160 (n = 2), or 40 mg/day (n = 1). All 13 (100%) patients with the T790M mutation and 4 (57%) of those without it obtained clinical responses. Among the 11 radiologically assessable patients, 9 (82%) responded, with 5 responses reported within 15 days after treatment initiation. Median overall survival and progression-free survival were 18.0 and 17.2 months, respectively, from the start of osimertinib.

CONCLUSIONS

In this non-selected population, osimertinib had remarkable efficacy in NSCLC patients with LM irrespective of the presence of the EGFR-T790M-resistance mutation. Osimertinib efficacy was rapid in several patients, even some with poor performance status.

Afatinib in locally advanced/metastatic NSCLC harboring common EGFR mutations, after chemotherapy: a Phase IV study

Aim

The current study evaluated the efficacy and tolerability of second-line afatinib in patients with EGFR mutation-positive (EGFRm+) non-small-cell lung cancer (NSCLC) following chemotherapy.

Patients & methods

In this open-label, single-arm Phase IV study, patients with EGFRm+ (Del19/L858R) NSCLC who had progressed following platinum-based chemotherapy received afatinib (starting dose 40 mg/day). The primary end point was confirmed objective response.

Results

60 patients received afatinib for a median duration of 11.5 months. 50% of patients had a confirmed objective response, of median duration 13.8 months. Median progression-free survival was 10.9 months. The most common treatment-related adverse events were diarrhea (72%), rash (28%) and paronychia (23%).

Conclusion

Our data support the use of afatinib (40 mg/day) as an effective and well-tolerated second-line treatment in EGFRm+ NSCLC.

Optimizing outcomes and treatment sequences in EGFR mutation-positive non-small-cell lung cancer: recent updates

The availability of several EGFR tyrosine kinase inhibitors (TKIs) for the treatment of EGFR mutation-positive NSCLC poses important questions regarding the optimum sequence of therapy. A key consideration is how best to use the third-generation TKI, osimertinib. While osimertinib has demonstrated impressive efficacy and tolerability in a first-line setting, there are currently no standard targeted treatment options following progression. There is an argument, therefore, for reserving osimertinib for second-line use in patients who acquire the T790M resistance mutation after first- or second-generation TKIs. This article reviews recent clinical studies that have assessed the activity of sequential EGFR TKI regimens. These studies support the hypothesis that sequential use of EGFR TKIs represents a viable treatment option in 'real-world' clinical practice.

A Novel Three-Dimensional Glioma Blood-Brain Barrier Model for High-Throughput Testing of Tumoricidal Capability

The blood-brain barrier (BBB) limits passage of substances between general circulation and the brain extracellular fluid, maintaining homeostasis in neural tissues and providing a defense against potential toxins. However, the protection provided by the BBB often prevents conventional chemotherapeutics from reaching brain tumors which makes brain cancers one of the most difficult cancers to treat (1). Traditionally, high-throughput testing of compound permeability through the BBB in vitro has been limited to assay of radio- or fluorophore-labeled compounds as they pass a cell monolayer growing on a permeable support system. Unfortunately, the labels themselves may negatively impact the assay, and the ability to determine resulting tumor cytotoxicity must be studied independently. The present study demonstrates proof-of-concept of a three-dimensional (3D) model to study label-free BBB transport as well as the resulting brain tumor cytotoxicity by combining two commercially available products: Corning® HTS Transwell®-96 tissue culture system and Corning 96-well spheroid microplates. Transwells are permeable support systems commonly used for drug transport and migration/invasion studies (2, 3). Corning spheroid microplates are cell culture microplates with round well-bottom geometry coated with Corning Ultra-low Attachment surface, enabling the formation of a single multicellular tumor spheroid centered in each well in a highly reproducible manner. By replacing the standard flat-bottom Transwell receiver plate with a Corning spheroid microplate, the resulting system—which can be tailored to any number of cell types and screening applications—enables a more comprehensive assay to study drug transport across the BBB and the resulting 3D glioma spheroid toxicity in an easy-to-use 3D high-throughput assay.

First-line afatinib for the treatment of EGFR mutation-positive non-small-cell lung cancer in the 'real-world' clinical setting

Afatinib is an ErbB family blocker that is approved for the treatment of epidermal growth factor receptor (EGFR) mutation-positive non-small-cell lung cancer (NSCLC). Pivotal randomized clinical studies demonstrated that afatinib significantly prolonged progression-free survival compared with platinum-based chemotherapy (LUX-Lung 3, LUX-Lung 6), and with gefitinib (LUX-Lung 7), with manageable side effects. However, these results were derived from controlled studies conducted in selected patients and are not necessarily representative of real-world use of afatinib. To gain a broader understanding of the effectiveness and safety of first-line afatinib, we have undertaken a literature review of real-world studies that have assessed its use in a variety of patient populations. We focused on patients with uncommon EGFR mutations, brain metastases, or those of advanced age, as these patients are often excluded from clinical studies but are regularly seen in routine clinical practice. The available real-world studies suggest that afatinib has clinical activity, and is tolerable, in diverse patient populations in an everyday clinical practice setting. Moreover, consistent with LUX-Lung 7, several real-world comparative studies indicate that afatinib might confer better efficacy than first-generation EGFR tyrosine kinase inhibitors. Tolerability-guided dose adjustment, undertaken in 21-68% of patients in clinical practice, did not appear to reduce the efficacy of afatinib. Taken together, these findings provide further support for the use of afatinib as a treatment option in patients with EGFR mutation-positive NSCLC.

Small molecule inhibitors targeting the EGFR/ErbB family of protein-tyrosine kinases in human cancers

The EGFR family is among the most investigated receptor protein-tyrosine kinase groups owing to its general role in signal transduction and in oncogenesis. This family consists of four members that belong to the ErbB lineage of proteins (ErbB1-4). The ErbB proteins function as homo and heterodimers. These receptors contain an extracellular domain that consists of four parts: domains I and III are leucine-rich segments that participate in growth factor binding (except for ErbB2) and domains II and IV contain multiple disulfide bonds. Moreover, domain II participates in both homo and heterodimer formation within the ErbB/HER family of proteins. Seven ligands bind to EGFR including epidermal growth factor and transforming growth factor-α, none bind to ErbB2, two bind to ErbB3, and seven ligands bind to ErbB4. The extracellular domain is followed by a single transmembrane segment of about 25 amino acid residues and an intracellular portion of about 550 amino acid residues that contains (i) a short juxtamembrane segment, (ii) a protein kinase domain, and (iii) a carboxyterminal tail. ErbB2 lacks a known activating ligand and ErbB3 is kinase impaired. Surprisingly, the ErbB2-ErbB3 heterodimer complex is the most active dimer in the family. These receptors are implicated in the pathogenesis of a large proportion of lung and breast cancers, which rank first and second, respectively, in the incidence of all types of cancers (excluding skin) worldwide. On the order of 20% of non-small cell lung cancers bear activating mutations in EGFR. More than 90% of these patients have exon-19 deletions (⁷⁴⁶ELREA⁷⁵⁰) or the exon-21 L858R substitution. Gefitinib and erlotinib are orally effective type I reversible EGFR mutant inhibitors; type I inhibitors bind to an active enzyme conformation. Unfortunately, secondary resistance to these drugs occurs within about one year owing to a T790M gatekeeper mutation. Osimertinib is an irreversible type VI inhibitor that forms a covalent bond with C797 of EGFR and is FDA-approved for the treatment of patients with this mutation; type VI inhibitors generally form a covalent adduct with their target protein. Resistance also develops to this and related type VI inhibitory drugs owing to a C797S mutation; the serine residue is unable to react with the drugs to form a covalent bond. Approximately 20% of breast cancer patients exhibit ErbB2/HER2 gene amplification on chromosome 17q. One of the earliest targeted treatments in cancer involved the development of trastuzumab, a monoclonal antibody that interacts with the extracellular domain ErbB2/HER2 causing its down regulation. Surgery, radiation therapy, chemotherapy with cytotoxic drugs, and hormonal modulation are the mainstays in the treatment of breast cancer. Moreover, lapatinib and neratinib are FDA-approved small molecule ErbB2/HER2 antagonists used in the treatment of selected breast cancer patients. Of the approximate three dozen FDA-approved small molecule protein kinase inhibitors, five are type VI irreversible inhibitors and four of them including afatinib, osimertinib, dacomitinib, and neratinib are directed against the ErbB family of receptors (ibrutinib is the fifth and it targets Bruton tyrosine kinase). Avitinib, olmutinib, and pelitinib are additional type VI inhibitors in clinical trials for non-small cell lung cancer that target EGFR. Secondary resistance to both targeted and cytotoxic drugs is the norm, and devising and implementing strategies for minimizing or overcoming resistance is an important goal in cancer therapeutics.

Sequential treatment with afatinib and osimertinib in patients with EGFR mutation-positive non-small-cell lung cancer: an observational study

Aim: To assess outcomes in patients with EGFR mutation-positive (Del19, L858R) non-small-cell lung cancer receiving sequential afatinib and osimertinib in a real-world clinical setting. Materials & methods: In this retrospective, observational, multicenter study, patients (n = 204) had T790M-positive disease following first-line afatinib and started osimertinib treatment ≥10 months prior to data entry. Primary outcome was time on treatment. Results: Overall median time on treatment was 27.6 months (90% CI: 25.9–31.3), 30.3 months (90% CI: 27.6–44.5) in Del19-positive patients and 46.7 months (90% CI: 26.8–not reached) in Asians. The 2-year overall survival was 78.9%. Conclusion: In real-world clinical practice, sequential afatinib and osimertinib facilitates prolonged, chemotherapy-free treatment in patients with T790M acquired resistance, and is a potentially attractive strategy, especially for Del19-positive tumors.

Trial registration number: NCT03370770

Overview of the LUX-Lung clinical trial program of afatinib for non-small cell lung cancer

Tyrosine kinase inhibitors (TKIs) have emerged as first-line treatment for the management of epidermal growth factor receptor (EGFR)-mutated advanced non-small cell lung cancer (NSCLC). Erlotinib and gefitinib were the initial TKIs to be approved for lung cancer and showed improved response rates compared with chemotherapy. Afatinib is an irreversible ErbB family blocker that has also been shown to be active in EGFR-mutated NSCLC. Afatinib has been tested as first-line treatment of advanced NSCLC in the LUX-Lung trial program, as well as in the second- and third-line settings. In this article, we will review the data from the 8 reported LUX-Lung trials.