EGFR Exon 20 Insertion Mutations: Clinicopathological Characteristics and Treatment Outcomes in Advanced Non–Small Cell Lung Cancer

BackgroundEpidermal growth factor receptor gene (EGFR) exon 20 insertion (ex20-ins) mutations are an uncommon and heterogeneous group of non–small cell lung cancers (NSCLCs), resistant to conventional EGFR tyrosine kinase inhibitors (TKIs). Characteristics and outcomes of patients with EGFR ex20-ins have not been fully established; we sought to clarify them using a multinational patient database.Patients and MethodsPatients with NSCLC from six Australian institutions with EGFR exon 20 mutations (ex20-mut), excluding T790M, were retrospectively reviewed. Clinical characteristics and outcomes with systemic treatments were collected and analyzed using comparative statistics.ResultsAmong 109 patients with ex20-mut, 61% were females and 75% were Caucasians. More males presented with de novo metastatic disease (84% vs. 51%; P = .002). Central nervous system (48%) and liver (24%) metastases were common within metastatic patients (n = 86). Thirty-nine patients received platinum-based chemotherapy (PBC) and achieved a 43% objective response rate (ORR), median progression-free survival (mPFS) of 6.9 months, and median overall survival (mOS) of 31.0 months. Twenty-three of the patients with ex20-ins received conventional TKIs, resulting in an ORR of 13%, mPFS of 3.4 months (95% confidence interval [CI], 1.91-6.25), and mOS of 31.0 months (95% CI, 15.09-not reached). Nine patients with S786I mutations received TKIs, resulting in an ORR of 50%, mPFS of 18.2 months (2.79-not reached), and mOS of 33.4 months (95% CI, 16.14-not reached). Twenty-three patients received immune checkpoint inhibitor monotherapy (ICIm), resulting in an ORR of 4%, mPFS of 2.6 months (95% CI, 1.91-4.83), and mOS of 30.8 months (95% CI, 17.62-41.62).ConclusionAlthough phenotypically similar to patients with common EGFR mutations, patients with EGFR ex20-mut had worse survival, perhaps due to the lack of targeted therapies. Chemotherapy was superior to conventional EGFR TKIs in patients with EGFR ex20-ins, although there was moderate activity of TKIs in S768I mutations. ICIm was ineffective.     

Activity of Afatinib in Heavily Pretreated Patients With ERBB2 Mutation–Positive Advanced NSCLC: Findings From a Global Named Patient Use Program

Introduction

Approximately 1% to 4% of NSCLC tumors harbor erb-b2 receptor tyrosine kinase 2 (ERBB2) mutation; there is no approved targeted treatment for this subgroup.

Cell-Free Plasma DNA-Guided Treatment With Osimertinib in Patients With Advanced EGFR-Mutated NSCLC

Introduction

Osimertinib is standard treatment for patients with advanced EGFR T790M-mutated non–small-cell lung cancer who have been pre-treated with EGFR–tyrosine kinase inhibitors (TKIs). We studied whether cell-free plasma DNA for T790M detection can be used to select patients for osimertinib treatment in the clinical routine.

Use of Cetuximab After Failure of Gefitinib in Patients With Advanced Non–Small-Cell Lung Cancer

BackgroundGefitinib and cetuximab are both epidermal growth factor receptor (EGFR) target therapies used to treat patients with non–small-cell lung cancer (NSCLC) with different mechanisms. To clarify the effectiveness of cetuximab after failure of gefitinib treatment, we investigated the clinical features of patients with NSCLC who received cetuximab-containing chemotherapy after failure of gefitinib.Patients and MethodsWe analyzed the clinical data and mutational studies of patients with NSCLC in the National Taiwan University Hospital who had received gefitinib and, after failure of gefitinib, cetuximab-containing chemotherapy.ResultsFifteen patients who received cetuximab-containing chemotherapy after failure of gefitinib were identified. Four were responders to gefitinib therapy, and 3 were responders to cetuximab-containing chemotherapy. Ten were sequenced for EGFR and KRAS mutations. Six of the 10 patients had EGFR mutations, and all 10 patients had wild-type (WT) KRAS. In the 4 patients who had the gefitinib-resistant EGFR T790M mutation, 2 were responders to cetuximab-containing chemotherapy. The other cetuximab responder had WT EGFR.ConclusionCetuximab might add benefit in treatment after failure of gefitinib, regardless of EGFR mutational status. Treatment with cetuximab should be further explored, even in patients who have previously received gefitinib treatment.     

Effectiveness of Treatments for Advanced Non–Small-Cell Lung Cancer With Exon 20 Insertion Epidermal Growth Factor Receptor Mutations

BackgroundTwo main categories of epidermal growth factor receptor (EGFR) mutations in non–small-cell lung cancer (NSCLC) patients are deletions in exon 19 and L858R in exon 21. Treatments of advanced NSCLC patients with these mutations are well documented, and clinical responses to tyrosine kinase inhibitors (TKIs) are favorable. However, effective treatments for patients with exon 20 insertion mutations are not well verified. We investigated the clinical response to various treatments (chemotherapy and TKIs) of advanced NSCLC patients with EGFR exon 20 insertions.Patients and MethodsIn this study, specimens from 3805 NSCLC patients were examined for EGFR mutations. Different first-line treatments and their effectiveness in NSCLC patients with exon 20 insertion EGFR mutations were investigated.ResultsIn the cohort of the 3805 patients, 2112 (55.5%) had EGFR mutations, including 84 patients (4.0%) with exon 20 insertion mutations. Efficacy of different first-line chemotherapy or TKIs were evaluated. Pemetrexed-containing therapies were related to better progression-free survival (6.2 vs. 2.7 months; P < .001) and overall survival (28.0 vs. 15.4 months; P = .009) than regimens without pemetrexed. Patients with exon 20 insertions had a poor response to TKIs. However, the mutation Ala763_Tyr764insPheGlnGluAla (A763_Y764 insFQEA) was related to a favorable response to TKIs.ConclusionExon 20 insertion EGFR mutations comprised a considerable group of the entire population of patients with EGFR mutations. Different first-line treatments and variants of the exon 20 insertions might be related to different outcomes in advanced NSCLC patients.     

EGFR–Co-Mutated Advanced NSCLC and Response to EGFR Tyrosine Kinase Inhibitors

ObjectivesThe evolution of EGFR tyrosine kinase inhibitors (TKIs) has changed the landscape of disease for a subset of patients with NSCLC. Most patients with an EGFR mutation respond to these drugs; however, a proportion show limited or no tumor response. We explored the impact of co-mutation (double or multiple mutation), compared with a single mutation, of the EGFR gene on response to TKIs in a series of patients with metastatic NSCLC.MethodsWe retrospectively analyzed the mutation profiles of nonsquamous NSCLC tested at Royal Prince Alfred Hospital between 2012 and 2015 by MassArray using the OncoCarta v1.0 panel. Patients with metastatic disease whose tumors had sensitizing EGFR mutation(s) were included. The primary end point was progression-free survival (PFS). We used the Kaplan-Meier method for PFS and overall survival; the log rank test was used to compare groups with and without co-mutation. Multivariable analysis was done for PFS; response rate was assessed using chi-square and logistic regression analysis.ResultsA total of 62 patients were included, and of these, eight (12.9%) had a co-mutation. The median PFS and overall survival times were 11.5 and 26.3 months, respectively. Patients with EGFR co-mutation had a significantly shorter median PFS than those with a single mutation (5.7 months versus 12.3 months, p = 0.02). The response rate to TKIs was significantly worse in those with co-mutation compared with in those without co-mutation (38% versus 89%, p < 0.001).ConclusionsTaking into account the small number of patients in this study, PFS in patients with EGFR co-mutation appeared significantly shorter, and response rate significantly lower, than in patients with a single mutation. Data from multipanel testing may identify subgroups of patients who are likely to respond poorly to standard treatment. Clarification of these subgroups may improve patient care.     

Phase 2 Study of Afatinib Alone or Combined With Bevacizumab in Chemonaive Patients With Advanced Non–Small-Cell Lung Cancer Harboring EGFR Mutations: AfaBev-CS Study Protocol

Afatinib, a second-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI), has demonstrated a significant survival benefit over platinum-based chemotherapy in a first-line setting in advanced non–small-cell lung cancer (NSCLC) harboring EGFR exon 19 deletion. In addition, we and other groups have shown there to be favorable progression-free survival (PFS) outcomes, with acceptable toxicity profiles, with bevacizumab and first-generation EGFR-TKI combination therapy. On the basis of the above, we hypothesized that a combination of bevacizumab and afatinib could potentially improve efficacy. In our phase 1 study, a daily 30 mg dose of afatinib and 15 mg/kg intravenous bevacizumab every 3 weeks was well tolerated and was defined as the recommended dose. We have initiated a randomized phase 2 trial comparing afatinib (30 mg daily) and bevacizumab (15 mg/kg every 3 weeks) with afatinib (40 mg daily) alone for nonsquamous NSCLC harboring EGFR common mutations as a first-line therapy. A total of 100 patients will be enrolled onto this study and randomized in a 1:1 ratio. Patients will continue to receive treatment until disease progression or unacceptable toxicity. The primary end point is PFS, and the secondary end points are overall survival, tumor response, and time to treatment failure. The power is greater than 50% under the assumptions of a median PFS of 12 months for the afatinib group and a hazard ratio of 0.6 for the combination group (2-sided α = 0.05). We hypothesize that the combination therapy will be more efficacious than standard therapies for EGFR-mutant NSCLC patients.     

Phase II Study of Cetuximab,Docetaxel, and Gemcitabine in Patients With Previously Untreated Advanced Non–Small-Cell Lung Cancer

BackgroundTargeting epidermal growth factor receptors (EGFRs) has been a novel strategy in treating non–small-cell lung cancer (NSCLC). This multicenter, community-based trial was designed to examine the role of cetuximab in combination with a nonplatinum regimen.Patients and MethodsEligibility criteria were newly diagnosed unresectable stage III/IV NSCLC, all histologies, measurable disease, and Eastern Cooperative Oncology Group performance status (ECOG PS) 0-2. Treatment premedication included dexamethasone 20 mg orally 12 and 6 hours before treatment, and 4 mg 12 hours following treatment; diphenhydramine 50 mg intravenously (I.V.) and cimetidine 300 mg I.V. before cetuximab. Treatment medication included docetaxel 30 mg/m² I.V. days 1 and 8; gemcitabine 1000 mg/m² I.V. days 1 and 8; and cetuximab 400 mg/m² I.V. day 1, then 250 mg/m² I.V. weekly. Patients received up to 6 cycles with restaging every 6 weeks. The primary endpoint was an overall response rate (ORR) ≥ 25%.ResultsSixty-nine patients enrolled from July 2005 to October 2007. Patients had a median age of 69 years; 70% were male and 30% were female; ECOG PS was 0 in 42%, 1 in 51%, and 2 in 7%; patients had adenocarcinoma (42%), squamous cell (30%), large cell (6%), mixed (1%), and not otherwise specified (20%) disease. The ORR was 17% (95% CI, 9%-29%). Thirty-five patients (54%) had stable disease; 14 patients (22%) had progressive disease. With a median follow-up of 17.8 months, the median progression-free and overall survivals were 4 months and 9.4 months, respectively. The most common (> 10%) grade 3/4 toxicities were neutropenia (25%), rash (22%), and fatigue (12%). Accrual in our middle Tennessee offices was temporarily suspended and ultimately stopped because of a higher-than-anticipated rate of cetuximab-related severe hypersensitivity reactions (HSRs) in 4 patients among the first 12 enrolled, including 1 fatal event.ConclusionCetuximab/docetaxel/gemcitabine was relatively well-tolerated and associated with efficacy similar to chemotherapy alone. Additional study with cetuximab/chemotherapy in NSCLC should focus on new potentially predictive biomarkers. Also, additional study is needed to better understand and prevent the severe HSRs that appear to be endemic to specific regions of the United States.     

Potential Benefits of Bevacizumab Combined With Platinum-Based Chemotherapy in Advanced Non–Small-Cell Lung Cancer Patients With EGFR Mutation

BackgroundOncogenic EGFR signaling has been shown to upregulate vascular endothelial growth factor A (VEGFA) expression involved in tumor angiogenesis. However, the clinical benefits of bevacizumab plus cytotoxic chemotherapy for EGFR mutation–positive patients remain unclear. This study aimed to investigate VEGFA messenger RNA expression in patients with EGFR mutation, and to further compare the efficacy of bevacizumab combined with platinum-based chemotherapy between EGFR-mutant and wild-type patients.Patients and MethodsGene expression of various proangiogenic factors was analyzed in nonsquamous, non–small-cell lung cancer (NSCLC) patients using The Cancer Genome Atlas dataset. Additionally, clinical data of patients receiving carboplatin and pemetrexed (CPem; n = 104) or bevacizumab plus CPem (BevCPem; n = 55) at Nagoya University hospital were retrospectively assessed for progression-free survival and best overall response rate (ORR).ResultsAmong various proangiogenic factors, only VEGFA expression was significantly higher in patients with advanced nonsquamous NSCLC with EGFR mutation compared to wild-type patients (P = .0476). Progression-free survival in the BevCPem group was significantly longer in patients with EGFR mutation than in wild-type patients (10.5 vs. 6.6 months; Wilcoxon P = .0278), while the difference in the CPem group was not significant (6.6 vs. 4.5 months; Wilcoxon P = .1822). The ORRs in the BevCPem group were 54.5% and 36.4% for EGFR-mutant and wild-type patients, respectively, and the ORRs in the CPem group were 35.5% and 28.8 % in EGFR-mutant and wild-type patients, respectively.ConclusionVEGFA messenger RNA expression was significantly increased in advanced nonsquamous NSCLC harboring EGFR mutation, and BevCPem provided better clinical benefits to patients with EGFR mutation than wild-type carriers.     

Afatinib in the treatment of EGFR mutation-positive NSCLC – A network meta-analysis

Objectives

Epidermal growth factor receptor (EGFR) mutation-positive non-small cell lung cancer (NSCLC) is a specific lung cancer subtype characterized by sensitivity to treatment with EGFR tyrosine kinase inhibitors (TKIs). Two reversible EGFR TKIs (gefitinib, erlotinib) and the irreversible ErbB family blocker afatinib are currently approved for treatment of EGFR mutation-positive NSCLC, but no head-to-head trials have been reported to date. We aimed to assess the relative efficacy of the three drugs by conducting a network meta-analysis (NMA).

Materials and methods

A systematic literature review was conducted to identify all the available evidence. Outcomes of interest were progression-free survival (PFS) and overall survival. For PFS, results by investigator review were considered as not all trials assessed PFS independently. Results were analyzed using Bayesian methods.

Results

The literature search identified 246 articles that were assessed for eligibility, of which 21 studies were included in the NMA, including eight trials performed in an EGFR mutation-positive population. The estimated PFS HR (95% credible interval, CrI) for afatinib compared with gefitinib was 0.70 (0.40–1.16) and compared with erlotinib was 0.86 (0.50–1.50) in the total population. The estimated probability of being best for afatinib over all other treatments for PFS was 70% versus 27% for erlotinib and 3% for gefitinib; the estimated probability of chemotherapy being the best treatment was 0%. Estimated HR (95% CrI) in patients with common mutations was 0.73 (0.42–1.24) for afatinib compared with erlotinib and 0.60 (0.34–0.99) for afatinib compared with gefitinib. OS findings were not significantly different between treatments.

Conclusions

In the absence of direct head-to-head trial data comparing efficacy between the three EGFR TKIs, our analysis suggests that afatinib is a viable treatment alternative to erlotinib or gefitinib in terms of PFS. A direct trial-based comparison of the efficacy of these agents is warranted to clarify their relative benefits.     

Access to Tyrosine Kinase Inhibitors and Survival in Patients with Advanced EGFR+ and ALK+ Positive Non–small-cell Lung Cancer Treated in the Real-World

IntroductionWe assessed the proportion of patients with advanced epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) positive non–small-cell lung cancer (NSCLC) who receive tyrosine kinase inhibitors (TKIs) in the real-world, predictors of TKI use, and impact of TKI therapy on overall survival (OS).Materials and MethodsWe identified patients diagnosed with stage IV EGFR⁺ and ALK⁺ positive NSCLC from January 1, 2010 to December 31, 2018, in the Cancer Surveillance System registry and linked their records to Medicare and commercial insurance claims. We reported the proportions of patients with 1 or more TKI claims versus no TKI claims and used logistic regression to identify predictors of TKI use. We evaluated the effect of TKI use on OS by applying extended Cox proportional hazard models with TKI use as a time-dependent exposure and landmark analysis in a subcohort (N = 105). We adjusted Cox models for confounding patient characteristics.ResultsOf 117 eligible patients (median age = 69; 62% women; 88% EGFR⁺), 21 (17.9%) had no TKI claims. Diagnosis in 2015 to 2018 was independently associated with lower likelihood of TKI therapy compared with 2010 to 2014 (adjusted odds ratio, 0.29; P = .020). TKI use was associated with longer OS in a multivariate extended Cox model and in the landmark analysis (adjusted hazard ratio [HR], 0.58; 95% confidence interval [CI], 0.33; 0.99; P = .048; adjusted HR, 0.55; 95% CI, 0.30; 1.00; P = .050).ConclusionApproximately 18% of patients with advanced EGFR⁺ and ALK⁺ positive NSCLC do not receive TKIs and have inferior survival. Further studies need to investigate barriers of access to TKIs in biomarker-selected patients.     

Interstitial Lung Disease Associated With Crizotinib in Patients With Advanced Non–Small Cell Lung Cancer: Independent Review of Four PROFILE Trials

Introduction

Interstitial lung disease (ILD) is a rare, but potentially serious, side effect associated with crizotinib, a tyrosine kinase inhibitor for anaplastic lymphoma kinase-positive (ALK⁺) advanced non–small cell lung cancer. Our objective was to determine the incidence and nature of ILD associated with crizotinib in 4 PROFILE trials (ClinicalTrials.gov identifiers, NCT00585195, NCT00932451, NCT00932893, and NCT01154140).

Real-World Evaluation of Factors for Interstitial Lung Disease Incidence and Radiologic Characteristics in Patients With EGFR T790M–positive NSCLC Treated With Osimertinib in Japan

IntroductionUsing real-world Japanese postmarketing data, we characterized interstitial lung disease (ILD) development during the second- or later-line osimertinib treatment for EGFR mutation-positive NSCLC. Retrospective radiologic image evaluation of patients developing ILD was also performed.MethodsPatients who had ILD events reported as an adverse drug reaction by their physicians and who were assessed as having developed ILD as assessed by an ILD expert committee in Japan were included.ResultsAmong 3578 patients, 252 ILD events were reported in 245 patients (6.8%) by their attending physicians. The median (range) time to the first onset of ILD after osimertinib treatment initiation was 63.0 (5–410) days, and 29 patients with a fatal outcome were reported. The ILD expert committee assessed 231 of 3578 patients (6.5%) as having ILD. A previous history of nivolumab therapy (adjusted OR: 2.84; 95% confidence interval: 1.98–4.07) and a history or concurrence of ILD (3.51; 2.10–5.87) were identified as factors potentially associated with ILD onset during osimertinib treatment. In patients who had received a previous nivolumab treatment, the number and proportion of patients developing ILD were highest for patients who discontinued nivolumab treatment within the first month before initiating osimertinib; trends for decreasing incidence and proportion were observed, with an increasing duration between the end of nivolumab treatment and the initiation of osimertinib treatment.ConclusionsThe frequency of ILD was consistent with the known osimertinib safety profile in the Japanese population. A history or concurrence of ILD and history of previous nivolumab therapy are factors potentially associated with ILD onset during osimertinib treatment.     

Relationship Between Prior Radiotherapy and Checkpoint-Inhibitor Pneumonitis in Patients With Advanced Non–Small-Cell Lung Cancer

PurposeTo investigate the relationship between radiotherapy (RT), in particular chest RT, and development of immune-related (IR) pneumonitis in non–small-cell lung cancer (NSCLC) patients treated with anti–programmed cell death 1 (PD-1)/programmed death ligand 1 (PD-L1).Patients and MethodsBetween June 2011 and July 2017, NSCLC patients treated with anti–PD-1/PD-L1 at a tertiary-care academic cancer center were identified. Patient, treatment, prior RT (intent, technique, timing, courses), and IR pneumonitis details were collected. Treating investigators diagnosed IR pneumonitis clinically. Diagnostic IR pneumonitis scans were overlaid with available chest RT plans to describe IR pneumonitis in relation to prior chest RT. We evaluated associations between patient, treatment, RT details, and development of IR pneumonitis by Fisher exact and Wilcoxon rank-sum tests.ResultsOf the 188 NSCLC patients we identified, median follow-up was 6.78 (range, 0.30-79.3) months and median age 66 (range, 39-91) years; 54% (n = 102) were male; and 42% (n = 79) had stage I-III NSCLC at initial diagnosis. Patients received anti–PD-1/PD-L1 monotherapy (n = 127, 68%) or PD-1/PD-L1-based combinations (n = 61, 32%). In the entire cohort, 70% (132/188) received any RT, 53% (100/188) chest RT, and 37% (70/188) curative-intent chest RT. Any grade IR pneumonitis occurred in 19% (36/188; 95% confidence interval, 13.8-25.6). Of those who developed IR pneumonitis and received chest RT (n = 19), patients were more likely to have received curative-intent versus palliative-intent chest RT (17/19, 89%, vs. 2/19, 11%; P = .051). Predominant IR pneumonitis appearances were ground-glass opacities outside high-dose chest RT regions.ConclusionNo RT parameter was significantly associated with IR pneumonitis. On subset analysis of patients who developed IR pneumonitis and who had received prior chest RT, IR pneumonitis was more common in patients who received curative-intent chest RT. Attention should be paid to NSCLC patients receiving curative-intent RT followed by anti–PD-1/PD-L1 agents.     

Clinical Activity of Afatinib in Patients With Non–Small-Cell Lung Cancer Harboring Uncommon EGFR Mutations: A Spanish Retrospective Multicenter Study

IntroductionUncommon epidermal growth factor receptor (EGFR) mutations (u-EGFRm) are a heterogeneous group of molecular alterations and have also been reported as comutations with other EGFR mutations (complex mutations) in non–small-cell lung cancer (NSCLC). Afatinib has shown activity against some u-EGFRm, and we examined its efficacy in Spanish clinical practice.Patients and MethodsData of 67 patients with advanced NSCLC with u-EGFRm treated with afatinib between 2012 and 2017 at 23 Spanish institutions were reviewed. u-EGFRm were analyzed as complex mutations (group A), EGFR exon 20 insertions (ins20; group B), or single mutations (group C). Efficacy was evaluated in terms of overall survival (OS) and tumor response.ResultsGroup A complex u-EGFRm consisted of double mutations of G719X+E709F, G719X+S768I, G719X+L861Q, L858R+T790M, L858R+S768I, L858R+S765I, del19+S768I, del19+L747S, or R776C+L861Q. No differences in clinical characteristics were found between groups A (n = 20), B (n = 23), and C (n = 24). Afatinib was administered as first-line therapy in 80% of patients. Median time of receipt of therapy was 4.2 months (range, 2.0–12.9 months). Median OS for the entire cohort was 19.9 months (95% confidence interval, 9.7, 30.1). Hazard ratios for OS were 0.26 (95% confidence interval, 0.10, 0.71; P = .008) and 0.40 (95% confidence interval, 0.17, 0.95; P = .037) for groups A and C compared to B, respectively. Response was significantly higher in groups A (70%) and C (54%) compared to B (13%; pairwise comparison P < .001 and .008, respectively).ConclusionIn clinical practice, afatinib was active in patients with u-EGFRm NSCLC, particularly in complex and single mutations. Further strategies are needed for patients with ins20, a subgroup u-EGFRm with a lower clinical benefit with afatinib.     

Intracranial Responses to Afatinib at Different Doses in Patients With EGFR-mutated Non–small-cell Lung Carcinoma and Brain Metastases

BackgroundAs the first-line treatment, afatinib is commonly used in patients with EGFR-mutated non–small-cell lung cancer (NSCLC). However, dose adjustments are frequently required. The optimal dose of afatinib for brain metastasis has seldom been investigated.Patients and MethodsFrom May 2014 to March 2017, treatment-naive patients with advanced EGFR-mutated NSCLC and brain metastases at diagnosis who received afatinib therapy were retrospectively enrolled. Clinical data was reviewed and analyzed, including age, gender, performance status, smoking history, EGFR mutation status, initial doses of afatinib, average daily doses of afatinib, and best intracranial treatment responses.ResultsA total of 74 patients were included for analysis. The overall intracranial objective response rate (IORR) and intracranial disease control rate (IDCR) were 81.1% and 95.9%, respectively. For patients treated with afatinib alone (N = 45), no significant difference between an initial daily dose of 30 mg (N = 15) and 40 mg (N = 30) (30 mg vs. 40 mg, IORR: 86.7% vs. 80.0%; P = .581 and IDCR: 93.3% vs. 93.3%; P = 1.000, respectively). The IORRs were 75.0%, 91.7%, 80.0%, and 85.7% (P = .707), and the IDCRs were 93.8%, 100.0%, 90.0%, and 85.7% (P = .638) in patients with an average daily dose of 40 mg (N = 16), < 40 mg and > 30 mg (N = 12), 30 mg (N = 10), and < 30 mg and > 20 mg (N = 7), respectively. No significant differences in intracranial treatment responses between groups treated with afatinib alone or afatinib plus local treatments.ConclusionDose reduction may not affect intracranial treatment responses to afatinib therapy, either alone or combined with local treatments, in patients with advanced EGFR-mutated NSCLC and brain metastases.