Targeting the EGFR pathway: An alternative strategy for the treatment of tuberous sclerosis complex?

INTRODUCTION: Tuberous sclerosis complex (TSC) is caused by variants in TSC1/TSC2, leading to constitutive activation of the mammalian target of rapamycin (mTOR) complex 1. Therapy with everolimus has been approved for TSC, but variations in success are frequent. Recently, caudal late interneuron progenitor (CLIP) cells were identified as a common origin of the TSC brain pathologies such as subependymal giant cell astrocytomas (SEGA) and cortical tubers (CT). Further, targeting the epidermal growth factor receptor (EGFR) with afatinib, which is expressed in CLIP cells, reduces cell growth in cerebral TSC organoids. However, investigation of clinical patient-derived data is lacking. AIMS: Observation of EGFR expression in SEGA, CT and focal cortical dysplasia (FCD) 2B human brain specimen and investigation of whether its inhibition could be a potential therapeutic intervention for these patients. METHODS: Brain specimens of 23 SEGAs, 6 CTs, 20 FCD2Bs and 17 controls were analysed via immunohistochemistry to characterise EGFR expression, cell proliferation (via Mib1) and mTOR signalling. In a cell-based assay using primary patient-derived cells (CT n = 1, FCD2B n = 1 and SEGA n = 4), the effects of afatinib and everolimus on cell proliferation and cell viability were observed. RESULTS: EGFR overexpression was observed in histological sections of SEGA, CT and FCD2B patients. Both everolimus and afatinib decreased the proliferation and viability in primary SEGA, tuber and FCD2B cells. CONCLUSION: Our study demonstrates that EGFR suppression might be an effective alternative treatment option for SEGAs and tubers, as well as other mTOR-associated malformations of cortical development, including FCD2B.

Single cell lineage tracing reveals clonal dynamics of anti-EGFR therapy resistance in triple negative breast cancer.

BACKGROUND: Most primary Triple Negative Breast Cancers (TNBCs) show amplification of the Epidermal Growth Factor Receptor (EGFR) gene, leading to increased protein expression. However, unlike other EGFR-driven cancers, targeting this receptor in TNBC yields inconsistent therapeutic responses. METHODS: To elucidate the underlying mechanisms of this variability, we employ cellular barcoding and single-cell transcriptomics to reconstruct the subclonal dynamics of EGFR-amplified TNBC cells in response to afatinib, a tyrosine kinase inhibitor (TKI) that irreversibly inhibits EGFR. RESULTS: Integrated lineage tracing analysis revealed a rare pre-existing subpopulation of cells with distinct biological signature, including elevated expression levels of Insulin-Like Growth Factor Binding Protein 2 (IGFBP2). We show that IGFBP2 overexpression is sufficient to render TNBC cells tolerant to afatinib treatment by activating the compensatory insulin-like growth factor I receptor (IGF1-R) signalling pathway. Finally, based on reconstructed mechanisms of resistance, we employ deep learning techniques to predict the afatinib sensitivity of TNBC cells. CONCLUSIONS: Our strategy proved effective in reconstructing the complex signalling network driving EGFR-targeted therapy resistance, offering new insights for the development of individualized treatment strategies in TNBC.

A real-world cohort study of first-line afatinib in patients with EGFR-mutant advanced non-small cell lung cancer in Vietnam.

BACKGROUND: This study aimed to evaluate the efficacy and side effects of first-line afatinib treatment in a real-world setting in Vietnam. METHODS: This retrospective study was conducted across nine hospitals in Vietnam. Advanced epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC) patients who received afatinib as first-line therapy between April 2018 and June 2022 were included, and patient medical records were reviewed. Key outcomes were overall response rate (ORR), time-to-treatment failure (TTF), and tolerability. RESULTS: A total of 343 patients on first-line afatinib were eligible for the study. EGFR exon 19 deletion (Del19) alone was detected in 46.9% of patients, L858R mutation alone in 26.3%, and other uncommon EGFR mutations, including compound mutations, in 26.8%. Patients with brain metastases at baseline were 25.4%. Patients who received 40 mg, 30 mg, and 20 mg as starting doses of afatinib were 58.6%, 39.9%, and 1.5%, respectively. The ORR was 78.1% in the overall population, 82.6% in the Del19 mutation subgroup, 73.3% in the L858R mutation subgroup, and 75.0% in the uncommon mutation subgroup (p > 0.05). The univariate and multivariate analyses indicate that the ORR increased when the starting dose was 40 mg compared to starting doses below 40 mg (83.9% vs. 74.3%, p = 0.034). The median TTF (mTTF) was 16.7 months (CI 95%: 14.8-18.5) in all patients, with a median follow-up time of 26.2 months. The mTTF was longer in patients in the common EGFR mutation subgroup (Del19/L858R) than in those in the uncommon mutation subgroup (17.5 vs. 13.8 months, p = 0.045) and in those without versus with brain metastases at baseline (17.5 vs. 15.1 months, p = 0.049). There were no significant differences in the mTTF between subgroups based on the starting dose of 40 mg and < 40 mg (16.7 vs. 16.9 months, p > 0.05). The most common treatment-related adverse events (any grade/grade ≥ 3) were diarrhea (55.4%/3.5%), rash (51.9%/3.2%), paronychia (35.3%/5.0%), and stomatitis (22.2%/1.2%). CONCLUSIONS: Afatinib demonstrated clinical effectiveness and good tolerability in Vietnamese EGFR-mutant NSCLC patients. In our real-world setting, administering a starting dose below 40 mg might result in a reduction in ORR; however, it might not have a significant impact on TTF.

Mechanism of action of adapalene for treating EGFR-TKI-induced skin disorder.

BACKGROUND: Skin disorders are the most common side effect associated with epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) therapy. It is important to manage skin lesions. Adapalene has been used to treat skin lesions caused by EGFR-TKIs in some cases. The aim of this study was to investigate the functional mechanism of adapalene in erlotinib-induced skin disorder. METHODS: To analyze the effect of adapalene on skin rash, afatinib and adapalene were administered to mice. The relationship between the concentration of adapalene and skin disorders was also examined by analyzing AQP3 expression. A skin lesion model was experimentally established in human skin keratinocytes (HaCaT) by using erlotinib with TNF-α and IL-1ß. We used qRT-PCR to analyze chemokine-induced inflammation and western blotting to analyze the effects of adapalene on the NF-κB signaling pathway. Antimicrobial peptides and adhesion factors were also examined using qRT-PCR. RESULTS: Mice administered 0.01% adapalene had less skin inflammation than mice treated with afatinib alone. The expression level of AQP3 decreased in an adapalene concentration-dependent manner. The mRNA levels of proinflammatory cytokines such as CCL2 and CCL27 in HaCaT cells were significantly reduced by adapalene. The expression of an antimicrobial peptide, hBD3, was upregulated after adapalene treatment. Adhesion factors, such as E-cadherin, were significantly downregulated by EGFR-TKI and significantly upregulated by adapalene treatment. Western blot analysis suggested that erlotinib-induced phosphorylation of p65 was decreased by adapalene. CONCLUSION: We suggest that adapalene may be a possible treatment option for skin disorders induced by EGFR-TKIs.

Afatinib treatment of severe respiratory failure due to malignant lymphangitis in a dialysis patient with squamous cell carcinoma of the lung.

Patients on dialysis have limited treatment options for advanced lung cancer because some chemotherapeutic agents are unavailable due to renal dysfunction. A man in his 70s on peritoneal dialysis presented with persistent fever refractory to antibiotics for 2 weeks. Subsequent whole-body CT showed a 5 cm diameter mass in the right lower lobe of the lung with right-sided pleural effusion and osteolytic metastasis of the right iliac bone. The patient was diagnosed with squamous cell carcinoma (cT3N2M1b, stage IVB) harbouring the p.Gly719Ala point mutation on exon 18 of the epidermal growth factor receptor. The patient developed severe respiratory failure due to malignant lymphangitis after a bronchoscopy. He received 30 mg/day of afatinib, resulting in tumour shrinkage and recovery from respiratory failure. We advocate for aggressive screening of driver oncogenes in patients with lung cancer on dialysis, including those with squamous cell lung cancer.

Real-world outcomes associated with afatinib use in patients with solid tumors harboring NRG1 gene fusions.

OBJECTIVES: Neuregulin-1 (NRG1) fusions may drive oncogenesis via constitutive activation of ErbB signaling. Hence, NRG1 fusion-driven tumors may be susceptible to ErbB-targeted therapy. Afatinib (irreversible pan-ErbB inhibitor) has demonstrated activity in individual patients with NRG1 fusion-positive solid tumors. This study collected real-world data on demographics, clinical characteristics, and clinical outcomes in this patient population. MATERIALS AND METHODS: In this retrospective, multicenter, non-comparative cohort study, physicians in the US-based Cardinal Health Oncology Provider Extended Network collected data from medical records of patients with NRG1 fusion-positive solid tumors who received afatinib (afatinib cohort) or other systemic therapies (non-afatinib cohort) in any therapy line. Objectives included demographics, clinical characteristics, and outcomes (overall response rate [ORR], progression-free survival [PFS], and overall survival [OS]). RESULTS: Patients (N = 110) with a variety of solid tumor types were included; 72 received afatinib, 38 other therapies. In the afatinib cohort, 70.8 % of patients received afatinib as second-line treatment and Eastern Cooperative Oncology Group performance status (ECOG PS) was 2-4 in 69.4 % at baseline. In the non-afatinib cohort, 94.7 % of patients received systemic therapy as first-line treatment and ECOG PS was 2-4 in 31.6 % at baseline. In the afatinib cohort, ORR was 37.5 % overall (43.8 % when received as first-line therapy); median PFS and OS were 5.5 and 7.2 months, respectively. In the non-afatinib cohort, ORR was 76.3 %; median PFS and OS were 12.9 and 22.6 months, respectively. CONCLUSION: This study provides real-world data on the characteristics of patients with NRG1 fusion-positive solid tumors treated with afatinib or other therapies; durable responses were observed in both groups. However, there were imbalances between the cohorts, and the study was not designed to compare outcomes. Further prospective/retrospective trials are required.

Differential efficacy of tyrosine kinase inhibitors according to the types of EGFR mutations and agents in non-small cell lung cancer: a real-world study.

BACKGROUND: Both first and second-generation EGFR-TKIs are recommended in advanced NSCLC with common EGFR mutations. However, there are few data on the difference in efficacy of EGFR-TKIs based on the type of EGFR mutation and agents. METHODS: This retrospective real-world study evaluated the outcomes and clinicopathologic characteristics, including the type of EGFR mutations, of 237 advanced NSCLC patients treated with first- or second-generation (afatinib) EGFR-TKIs as first-line therapy. RESULTS: The median progression-free survival (PFS) and overall survival (OS) of all patients were 11 months (M) and 25M, respectively. In the univariate analysis, patients with exon 19 deletion (del) (n=130) had significantly longer median OS compared to those with other mutations (L858R: 84, others: 23) (30 vs. 22 M, p=0.047), without a difference in PFS (p=0.138). Patients treated with afatinib (n=60) showed significantly longer median OS compared to those treated with first-generation TKIs (gefitinib: 159, erlotinib: 18) (30 vs. 23 M, p=0.037), without a difference in PFS (p=0.179). In patients with exon 19 del, there was no significant difference in median PFS (p=0.868) or OS (p=0.361) between patients treated with afatinib and those treated with first-generation TKIs, while significantly better PFS (p=0.042) and trend in OS (p=0.069) were observed in patients receiving afatinib in other mutations. Exon 19 del was independently associated with favorable OS (p=0.028), while age >70 years (p=0.017), ECOG performance status ≥2 (p=0.001), primary metastatic disease (p=0.007), and synchronous brain metastasis (p=0.026) were independent prognostic factors of poor OS. CONCLUSIONS: The EGFR exon 19 del was associated with favorable OS in advanced NSCLC patients receiving first-line EGFR-TKIs. Moreover, in patients with exon 19 del, first-generation TKIs seem to be a reasonable treatment option if osimertinib is unavailable.

Factors associated with prolonged progression-free survival of patients treated with first-line afatinib for advanced epidermal growth factor receptor-mutated non-small cell lung cancer.

BACKGROUND: This study aimed to investigate the factors associated with prolonged progression-free survival (PFS) (>36 months) of advanced non-small cell lung cancer (NSCLC) patients harboring epidermal growth factor receptor (EGFR) mutations treated with first-line afatinib. METHODS: We performed a retrospective analysis of data of patients with advanced EGFR-mutated NSCLC receiving first-line afatinib at two tertiary care referral centers, Linkou and Kaohsiung Chang Gung Memorial Hospital, in Taiwan between June 2014 and April 2022. RESULTS: The data of 546 treatment-naïve EGFR-mutated advanced NSCLC patients were analyzed. Median PFS and overall survival were 14.5 months and 27.2 months, respectively. The PFS of 462 patients (84.6%) was less than 36 months and of 84 patients (15.4%) was more than 36 months. The PFS > 36 months group had a significantly higher percentage of patients with uncommon mutations (p = 0.002). The PFS ≤36 months group had significantly higher incidences of bone, liver, and adrenal metastases (all p < 0.05) and a higher rate of multiple distant metastases. Multivariate logistic regression analysis showed that liver metastasis was negatively and independently associated with prolonged PFS (adjusted odds ratio = 0.246 [95% CI: 0.067-0.908], p = 0.035). The median overall survival of the PFS >36 months group was 46.0 months and that of the PFS ≤36 months group was 22.9 months (log-rank test, p < 0.001). CONCLUSIONS: We found that EGFR-mutated NSCLC patients receiving first-line afatinib were prone to shorter PFS if they had distant organ metastasis, especially liver metastasis.

Effectiveness and safety of afatinib, gefitinib, and erlotinib for treatment-naïve elderly patients with epidermal growth factor receptor-mutated advanced non-small-cell lung cancer: a multi-institute retrospective study.

BACKGROUND: In real-world practice, most patients with lung cancer are diagnosed when they are aged ≥65 years. However, clinical trials tend to lack data for the elderly population. Therefore, we aimed to describe the effectiveness and safety of afatinib, gefitinib, and erlotinib for elderly patients with epidermal growth factor receptor (EGFR)-mutated advanced non-small-cell lung cancer (NSCLC). METHODS: Treatment-naïve patients with EGFR-mutated advanced NSCLC were enrolled at many hospitals in Taiwan. Patient characteristics and the effectiveness and safety of afatinib, gefitinib, and erlotinib were compared. RESULTS: This study enrolled 1,343 treatment-naïve patients with EGFR-mutated advanced NSCLC, of whom 554 were aged <65 years, 383 were aged 65-74 years, 323 were aged 75-84 years, and 83 were aged ≥85 years. For elderly patients, afatinib was more effective, with a median progression-free survival (PFS) of 14.7 months and overall survival (OS) of 22.2 months, than gefitinib (9.9 months and 17.7 months, respectively) and erlotinib (10.8 months and 18.5 months, respectively; PFS: p = 0.003; OS: p = 0.026). However, grade ≥3 adverse events, including skin toxicities, paronychia, mucositis, and diarrhea, were more frequently experienced by patients receiving afatinib than those receiving gefitinib or erlotinib. CONCLUSIONS: This large retrospective study provides real-world evidence of the effectiveness and safety of EGFR-TKIs for elderly patients with EGFR-mutated advanced NSCLC, a population that is often underrepresented in clinical trials and real-world evidence. Afatinib was more effective as a first-line treatment than gefitinib or erlotinib for elderly patients with EGFR-mutated advanced NSCLC.

Ligand and structure based hierarchical virtual screening cascade for finding novel epidermal growth factor receptor inhibitors.

The epidermal growth factor receptor (EGFR) tyrosine kinase plays an important role in tumor formation and growth by mediating cell growth and other physiological processes. Therefore, EGFR is a promising target for the treatment of cancer. In this work, we combined ligand-based and structure-based virtual screening methods to identify novel EGFR inhibitors from a library of more than 103 thousand compounds. We first obtained hundreds of compounds with similar physiochemical properties through 3D molecular shape and electrostatic similarity screening with potent inhibitors AEE788 and Afatinib as queries. Next, we identified compounds with strong binding affinities to the EGFR pocket through molecular docking, which makes good use of the structure information of the receptor. After molecular scaffold analysis, our bioassay confirmed 13 compounds with EGFR inhibitory activity and three compounds had IC50 values below 1000 nM. In addition, we collected 5371 EGFR inhibitors from online databases, and clustered them into 7 groups by K-means method using their ECFP4 fingerprints as input. Each cluster had typical molecular fragments and corresponding activity characteristics, which could guide the design of EGFR inhibitors, and we concluded that the fragments from some of the hits are indicated in the highly active scaffolds.

A phase 2 trial combining afatinib with cetuximab in patients with EGFR exon 20 insertion-positive non-small cell lung cancer.

BACKGROUND: Epidermal growth factor receptor (EGFR) exon 20 insertion (ex20ins) mutations are the third most common EGFR mutations in patients with non-small cell lung cancer (NSCLC) and are associated with primary resistance to EGFR tyrosine kinase inhibitors (TKIs). There is evidence of activity of combining EGFR TKIs with monoclonal antibodies. This study reports on the efficacy and safety of afatinib in combination with cetuximab. METHODS: In this single-arm phase 2 trial, patients with advanced NSCLC harboring an EGFR ex20ins mutation were treated with afatinib 40 mg once daily in combination with cetuximab 500 mg/m2 every 2 weeks. The primary end point was disease control rate (DCR) at 18 weeks of treatment. RESULTS: Thirty-seven patients started treatment, with a median age of 65 years (range, 40-80 years), 78% female, and 95% White. The study achieved its primary end point with a DCR of 54% at 18 weeks, an overall response rate (ORR) of 43%, and a 32% confirmed ORR. Best responses were partial (n = 16), stable (n = 16), progressive disease (n = 2), or not evaluable (n = 3). Median progression-free survival was 5.5 months (95% CI, 3.7-8.3 months) and median overall survival was 16.8 months (95% CI, 10.7-25.8 months). The most common treatment-related adverse events (TRAEs) were diarrhea (70%), rash (65%), dry skin (59%), paronychia (54%), and erythema (43%). Grade 3 TRAEs were reported in 54% of all patients. CONCLUSIONS: Combination treatment with afatinib and cetuximab demonstrated antitumor activity with a DCR of 54% at 18 weeks and a 32% confirmed ORR. Toxicity was significant, although manageable, after dose reduction.

Successful treatment of severe lung cancer caused by third-generation EGFR-TKI resistance due to EGFR genotype conversion with afatinib plus anlotinib.

Third-generation EGFR-TKIs can be used to treat advanced non-small cell lung cancer patients with T790M resistance mutation induced by first- or second-generation EGFR-TKIs. However, it will also result in drug resistance, and the resistance mechanisms of third-generation EGFR-TKIs are complex. Here we reported a patient diagnosed with advanced lung adenocarcinoma and EGFR positive in September 2016. Following first-line targeted therapy with gefitinib, genetic testing showed EGFR T790M positive, which resulted in a change to osimertinib targeted therapy. In May 2021, troponin and creatinine levels were elevated, and the tumor hyperprogressed to severe lung cancer. Repeated genetic testing revealed that EGFR genotype converted to a non-classical mutation and EGFR T790M turned negative, which caused third-generation EGFR-TKI resistance. As a result, afatinib combined with anlotinib was selected to stabilize the patient's condition. We were inspired by the case that it reflects the significance and necessity of exploring the resistance mechanism and dynamically detecting genetic status throughout the course of treatment, which may help realize individualized precision therapy, and maximize the potential of patient.

Aspirin boosts the synergistic effect of EGFR/p53 inhibitors on lung cancer cells by regulating AKT/mTOR and p53 pathways.

The regimen of afatinib and vinorelbine has been used to treat breast or lung cancer cells with some limitations. Aspirin alone or in combination with other agents has shown unique efficacy in the treatment of cancer. We designed a preclinical study to investigate whether the triple therapy of aspirin, afatinib, and vinorelbine could synergistically inhibit the growth of p53 wild-type nonsmall cell lung cancer (NSCLC) cells. Three NSCLC cells A549, H460, and H1975 were selected to study the effect of triple therapy on cell proliferation and apoptosis. Compared to single agents, triple therapy synergistically inhibited the proliferation of lung cancer cells with combination index <1. Meanwhile, the therapeutic index of triple therapy was superior to that of single agents, indicating a balance between efficacy and safety in the combination of three agents. Mechanistic studies showed that triple therapy significantly induced apoptosis by decreasing mitochondrial membrane potential, increasing reactive oxygen species, and regulating mitochondria-related proteins. Moreover, epidermal growth factor receptor (EGFR) downstream signaling proteins including JNK, AKT, and mTOR were dramatically suppressed and p53 was substantially increased after NSCLC cells were exposed to the triple therapy. We provided evidence that the triple therapy of aspirin, afatinib and vinorelbine synergistically inhibited lung cancer cell growth through inactivation of the EGFR/AKT/mTOR pathway and accumulation of p53, providing a new treatment strategy for patients with p53 wild-type NSCLC.

Treatment of Non-Small Cell Lung Cancer with Atypical EGFR Mutations.

OPINION STATEMENT: EGFR tyrosine kinase inhibitors (TKI) should always be considered when treating advanced/metastatic non-small cell lung cancer (NSCLC) with atypical EGFR mutations. The first choice of TKI depends on the specific mutation(s) present and its effect on structure and function of the EGFR protein. Afatinib is the only EGFR TKI currently FDA approved for atypical EGFR mutations and has the strongest data to support its use in PACC mutations, a subgroup of atypical EGFR mutations which includes G719X and S7681. Dacomitinib may also be an option for these mutations given similar efficacy to afatinib. In contrast, for classical-like mutations such as L861Q, osimertinib should be considered the first choice given that their behavior mimics that of the classical mutations exon 19 deletion and L858R. Osimertinib should also be utilized in the setting of a concurrent T790M mutation. Superior CNS penetrance and well managed toxicity profile may also be reasons to consider osimertinib. Given that the choice of TKI may depend on the specific mutation, it is crucial that every patient diagnosed with NSCLC undergo comprehensive sequencing to identify these mutations.

Randomized phase II study of preoperative afatinib in untreated head and neck cancers: predictive and pharmacodynamic biomarkers of activity.

There is no strong and reliable predictive biomarker in head and neck squamous cell carcinoma (HNSCC) for EGFR inhibitors. We aimed to identify predictive and pharmacodynamic biomarkers of efficacy of afatinib, a pan-HER tyrosine kinase inhibitor, in a window-of-opportunity trial (NCT01415674). Multi-omics analyses were carried out on pre-treatment biopsy and surgical specimen for biological assessment of afatinib activity. Sixty-one treatment-naïve and operable HNSCC patients were randomised to afatinib 40 mg/day for 21-28 days versus no treatment. Afatinib produced a high rate of metabolic response. Responders had a higher expression of pERK1/2 (P = 0.02) and lower expressions of pHER4 (P = 0.03) and pRB1 (P = 0.002) in pre-treatment biopsy compared to non-responders. At the cellular level, responders displayed an enrichment of tumor-infiltrating B cells under afatinib (P = 0.02). At the molecular level, NF-kappa B signaling was over-represented among upregulated genes in non-responders (P < 0.001; FDR = 0.01). Although exploratory, phosphoproteomics-based biomarkers deserve further investigations as predictors of afatinib efficacy.

Treatment outcomes of non-small cell lung cancers treated with EGFR tyrosine kinase inhibitors: a real-world cohort study.

BACKGROUND: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) are a standard of care treatment options in non-small cell lung cancer (NSCLC). The present study investigated real-world EGFR TKI use and patient outcomes in NSCLC. MATERIAL AND METHODS: We collected all the patients who had reimbursement for EGFR TKIs in Finland 2011-2020 and had data available at Finnish Cancer Registry. Survival and time-on-treatment (ToT) were analyzed from the first EGFR TKI purchase and patients were stratified according to the TKIs. RESULTS: Whole patient cohort consisted of 1498 individuals who were treated with erlotinib (n = 998), afatinib (n = 258), or gefitinib (n = 238). In the EGFR mutant cohort (all gefitinib users and afatinib users with non-squamous histology; n = 466), survival was comparable to registrational trials while patients treated with afatinib had improved survival (HR 0.67 CI 95% 0.53-0.85) and longer ToT (13.9 vs 11.9 months, NS) compared to those treated with gefitinib. Females treated with afatinib had improved survival (HR 0.61 CI 95% 0.44-0.83) and longer ToT (15.1 vs 12.5 months, NS) compared to gefitinib while similar was not observed in males. Later line osimertinib treatment was applied for 78 patients. Approximately 20% of the individuals treated with previous gefitinib or afatinib had later line osimertinib treatment. Efficacy analysis of osimertinib treated showed similar ToT and survival regardless of the first line EGFR TKI. CONCLUSIONS: EGFR mutants treated with afatinib have improved outcomes compared to gefitinib while later-line osimertinib was applied only for around 20% of the individuals. The study further highlights the good real-world performance of EGFR TKIs and sheds light on therapy sequencing.

Brain metastasis, EGFR mutation subtype and generation of EGFR-TKI jointly influence the treatment outcome of patient with EGFR-mutant NSCLC.

Non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutation is brain metastasis (BM)-prone. We determined the impact of this hallmark, along with EGFR subtype and generation of tyrosine kinase inhibitor (TKI) treatment, on patients' outcome. 553 metastatic EGFR-mutant NSCLC patients received front-line EGFR-TKI treatment. Progression-free survival (PFS), overall survival (OS) and secondary T790M rate were analysed. BM was observed in 211 (38.2%) patients. BM (HR 1.20 [95% CI 0.99-1.48]; p = 0.053), ECOG PS 0-1 (HR 0.71 [95% CI 0.54-0.93]; p = 0.014) and afatinib treatment (HR 0.81 [95% CI 0.66-0.99]; p = 0.045) were associated with PFS. Afatinib-treated patients without BM demonstrated a significantly longer PFS (16.3 months) compared to afatinib-treated patients with BM (13.7 months) and to gefitinib/erlotinib-treated patients with (11.1 months) or without BM (14.2 months; p < 0.001). CNS-only progression trended higher in afatinib-treated patients. ECOG PS 0-1 (HR 0.41 [95% CI 0.31-0.56]; p < 0.001) and EGFR L858R mutation (HR 1.46 [95% CI 1.13-1.88]; p = 0.003), but not BM, were the predictors for OS. BM (OR 2.02 [95% CI 1.02-4.08]; p = 0.040), afatinib treatment (OR 0.26 [95% CI 0.12-0.50]; p < 0.001) and EGFR L858R mutation (OR 0.55 [95% CI 0.28-1.05]; p = 0.070) were associated with secondary T790M rate. In BM patients, gefitinib/erlotinib-treated ones with 19 deletion mutation and afatinib-treated ones with L858R mutation had the highest and the lowest T790M rate (94.4% vs. 27.3%, p < 0.001), respectively. BM and generation of EGFR-TKI jointly impact PFS and secondary T790M rate in patients with EGFR-mutant NSCLC, whereas OS was mainly associated with EGFR subtype.

Evaluation of the risk of diarrhea induced by epidermal growth factor receptor tyrosine kinase inhibitors with cultured intestinal stem cells originated from crypts in humans and monkeys.

Severe diarrhea is a common side effect of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). We aimed to evaluate the risk of EGFR-TKI-induced diarrhea using spheroids of human and monkey crypt-derived intestinal stem cells. Intestinal spheroids exhibited higher toxic susceptibility to EGFR-TKIs than Caco-2 cells. As concentration of EGFR-TKIs increased, cellular ATP first decreased relative to the control condition, followed by an increase in LDH release, in contrast with their simultaneous changes with traditional cytotoxic anticancer drugs. The toxic sensitivity of spheroids to various EGFR-TKIs corresponded to clinical diarrhea incidence. Afatinib, a second-generation EGFR-TKI, exhibited higher toxic sensitivity compared with the first-generation ones, corresponding to the clinical evidence that afatinib-induced diarrhea is almost inevitable and severe. By contrast, the third-generation osimertinib, which reduces the risk of diarrhea, showed mitigated cytotoxicity compared with afatinib. For irreversible EGFR-TKIs, the decreased ATP level persisted or its recovery was delayed even after drug removal compared with reversible ones. Furthermore, the highest drug accumulation in spheroids (TKIspheroids) and inhibition potency against EGFR (TKIspheroids/Ki) were observed for afatinib. This system would be useful for predicting the risk of EGFR-TKI-induced diarrhea; moreover, on-target cytotoxicity against intestinal stem cells might contribute to clinically observed diarrhea.

Do patient characteristics affect EGFR tyrosine kinase inhibitor treatment outcomes? A network meta-analysis of real-world survival outcomes of East Asian patients with advanced non-small cell lung cancer treated with first-line EGFR-TKIs.

BACKGROUND: Despite the well-established efficacies of tyrosine kinase inhibitors (TKIs) in epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC), there is limited real-world evidence comparing their effectiveness according to patients' clinical characteristics. This network meta-analysis (NMA) compared survival outcomes among first-line EGFR-TKIs in different subgroups of East Asian patients with advanced NSCLC. METHODS: This NMA included real-world observational studies reporting outcomes with TKIs in patients aged >65 years, with baseline brain metastasis, with different Eastern Cooperative Oncology Group (ECOG) statuses, or with different common EGFR mutation types. RESULTS: In patients with the EGFR L858R mutation, afatinib resulted in significantly longer progression-free survival (PFS) than erlotinib (hazard ratio [HR]: 0.59, 95% confidence interval [CI]: 0.46-0.75) and gefitinib (HR: 0.41, 95% CI: 0.32-0.53). Similarly, in patients with the EGFR Del19 mutation, afatinib and erlotinib resulted in significantly longer PFS than gefitinib (HR: 0.48 with 95% CI: 0.33-0.71 and HR: 0.54 with 95% CI: 0.36-0.80, respectively). Moreover, afatinib resulted in significantly longer PFS than gefitinib in patients with brain metastasis (HR: 0.53, 95% CI: 0.33-0.87) or ECOG status 0-1 (HR: 0.37, 95% CI: 0.23-0.59). CONCLUSION: This NMA suggests that afatinib results in similar PFS to erlotinib and superior PFS than gefitinib in patients with Del19 mutant NSCLC, aged ≥65 years, with ECOG scores of 0-1, and with baseline brain metastasis.

A randomized phase II study of afatinib alone or combined with bevacizumab for treating chemo-naïve patients with non-small cell lung cancer harboring EGFR mutations.

BACKGROUND: Adding bevacizumab to first-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) prolonged the progression-free survival (PFS), but limited data are available for second-generation EGFR-TKIs. AfaBev-CS is a randomized, phase II trial comparing afatinib plus bevacizumab and afatinib alone as first-line treatment. PATIENTS AND METHODS: Untreated patients with non-squamous non-small cell lung cancer (NSCLC) harboring EGFR mutations (Del19 or L858R) were enrolled and randomly assigned to receive either afatinib (30 mg) plus bevacizumab (AfaBev group) or afatinib (40 mg) monotherapy (Afa group). The primary endpoint was PFS. The power was >50% under the assumptions of a median PFS of 12 months for the Afa group and hazard ratio (HR) of 0.6 for the AfaBev group. RESULTS: Between August 2017 and September 2019, 100 patients were enrolled. There was no significant difference in PFS between the groups. The median PFS was 16.3 and 16.1 months for the AfaBev and Afa groups, respectively, with an HR of 0.865 (95% confidence interval [CI], 0.539 to 1.388; p = 0.55). In terms of overall survival, there was no significant difference between the groups (HR, 0.84; 95% CI, 0.39 to 1.83; p = 0.67). The overall response rate was 82.6% and 76.6% in the AfaBev and Afa groups, respectively (p = 0.61). Grade ≥ 3 diarrhea, hypertension, acneiform rash, paronychia, and stomatitis were frequently observed in the AfaBev group. CONCLUSIONS: This study failed to show efficacy of AfaBev over Afa for improving PFS in untreated patients with EGFR-mutated NSCLC.