Afatinib for the Treatment of NSCLC Harboring Uncommon EGFR Mutations: A Database of 693 Cases

IntroductionLimited clinical data are available regarding the efficacy of EGFR tyrosine kinase inhibitors (EGFR TKIs) in patients with NSCLC harboring uncommon EGFR mutations. This pooled analysis assessed the activity of afatinib in 693 patients with tumors harboring uncommon EGFR mutations treated in randomized clinical trials, compassionate-use and expanded-access programs, phase IIIb trials, noninterventional trials, and case series or studies.MethodsPatients had uncommon EGFR mutations, which were categorized as follows: (1) T790M; (2) exon 20 insertions; (3) “major” uncommon mutations (G719X, L861Q, and S768I, with or without any other mutation except T790M or an exon 20 insertion); (4) compound mutations; and (5) other uncommon mutations. Key end points were overall response rate (ORR), duration of response, and time to treatment failure (TTF).ResultsIn EGFR TKI–naive patients (n = 315), afatinib demonstrated activity against major uncommon mutations (median TTF = 10.8 mo; 95% confidence interval [CI]: 8.1–16.6; ORR = 60.0%), compound mutations (median TTF = 14.7 mo; 95% CI: 6.8–18.5; ORR = 77.1%), other uncommon mutations (median TTF = 4.5 mo; 95% CI: 2.9–9.7; ORR = 65.2%), and some exon 20 insertions (median TTF = 4.2 mo; 95% CI: 2.8–5.3; ORR = 24.3%). The median duration of response for major uncommon mutations, compound mutations, other uncommon mutations, and some exon 20 insertions was 17.1, 16.6, 9.0, and 11.9 months, respectively. Activity of afatinib was also observed in EGFR TKI–pretreated patients (n = 378). A searchable database of these outcomes by individual genotype was generated.ConclusionsAfatinib has clinical activity in NSCLC against major uncommon and compound EGFR mutations. It also has broad activity against other uncommon EGFR mutations and some exon 20 insertions. The data support the use of afatinib in these settings.     

Pharmacokinetic drug evaluation of osimertinib for the treatment of non-small cell lung cancer

Introduction: First- and second-generation epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs), such as gefitinib, erlotinib, icotinib, and afatinib are the standard-of-care for first-line therapy of non-small-cell lung cancer (NSCLC) harboring activating EGFR mutations. Unfortunately, after initial activity of an average 9–13 months, disease progression has been reported in the majority of patients. In about 50% of cases the progression is due to the onset of the T790M mutation in exon 20 of the EGFR gene. Third-generation EGFR-TKIs targeting this mutation were investigated, with osimertinib the only reaching clinical practice.

Areas covered: A structured search of bibliographic databases for peer-reviewed research literature and of main meetings using a focused review question addressing osimertinib, was undertaken.

Expert opinion: Osimertinib is the standard-of-care for EGFR-mutated patients progressing to first-line EGFR-TKIs due to the acquired EGFR T790M mutation. Results from the head-to-head first-line trial comparing osimertinib versus gefitinib or erlotinib in activating EGFR mutations might change the front-line approach. Osimertinib in combination regimens, such as immunotherapy, and in adjuvant setting are ongoing. Thus, the strategic approach for the management of EGFR-mutated NSCLC patients will change further in the next few years.     

Critical Assessment in Routine Clinical Practice of Liquid Biopsy for EGFR Status Testing in Non–Small-Cell Lung Cancer: A Single-Laboratory Experience (LPCE,Nice, France)

BackgroundThe introduction of liquid biopsy using PCR-based assays into routine practice has had a strong impact on the treatment of EGFR-mutated lung adenocarcinoma and is now commonly used for routine testing of EGFR mutations in certain clinical settings. To assess whether the claimed benefits of PCR-based assays hold true in daily practice at a multicenter clinical institution, we assessed how treatment decisions are affected by PCR-based assays for the analysis of EGFR mutations from plasma samples in a centralized laboratory (LPCE, Nice, France).Patients and MethodsA total of 345 samples were analyzed using the US Food and Drug Administration–approved Cobas EGFR Mutation Test v2 and 103 using the Therascreen EGFR Plasma RGQ PCR Kit over 3 years (395 samples from 324 patients). Eleven plasma samples were validated independently using Cobas at 3 institutions, and 130 samples were analyzed using Stilla digital PCR. Clinical data were collected for 175 (54%) of 324 patients.ResultsCobas was superior to the Therascreen assay and demonstrated 100% reproducibility. Digital PCR showed only 48%, 83%, and 58% concordance with Cobas for exon 19 deletions, L858R mutations, and T790M mutations, respectively. Liquid biopsies helped inform and change treatment when resistance occurred and enabled the detection of EGFR mutations in patients when biopsy tissue results were unavailable.ConclusionPCR-based assays are a fast and convenient test, allowing the detection of primary and secondary EGFR mutations from plasma. Cobas proved to be a reliable test, whereas digital PCR produced too many inconclusive results to be currently recommended as a principal testing device.     

Traitement systémique des métastases cérébrales de cancer bronchique

Systemic treatment of lung cancer patients with brain metastases is based on clinical (presence of symptomatic intracranial lesions), pathological and molecular characteristics of the disease. The efficacy of standard platinum-based chemotherapy is comparable inside and outside the brain, justifying its use as front-line therapy. The intracranial efficacy of targeted therapies (EGFR tyrosine kinase inhibitors, ALK inhibitors) is demonstrated, and is globally superior to the efficacy of standard chemotherapy, justifying their use as front-line therapy in case of EGFR activating mutation or ALK rearrangement (providing the change in the crizotinib label in France). The concomitant use of whole brain radiotherapy and a systemic treatment (chemotherapy or targeted therapy) is not recommended in the absence of a demonstrated better efficacy and/or acceptable safety profile. Several trials are ongoing to assess new whole brain radiotherapy modalities, new targeted therapies alone or in combination, especially exploring immunotherapy.     

Afatinib in Non‐Small Cell Lung Cancer Harboring Uncommon EGFR Mutations Pretreated With Reversible EGFR Inhibitors

Background.

Afatinib, an irreversible ErbB family blocker, is approved for treatment of patients with previously untreated non-small cell lung cancer (NSCLC) harboring activating epidermal growth factor receptor (EGFR) mutations. Efficacy of afatinib in EGFR tyrosine kinase inhibitor-naïve (TKI-naïve) patients with uncommon EGFR mutations (other than exon 19 deletions or exon 21 point mutations) has been reported; however, efficacy in TKI-pretreated patients with uncommon EGFR mutations is unknown.

Materials and Methods.

In the afatinib compassionate use program (CUP), patients with advanced or metastatic, histologically confirmed NSCLC progressing after at least one line of chemotherapy and one line of EGFR-TKI treatment were enrolled. Demographic data, mutation type, response rates, time to treatment failure (TTF), and safety in patients harboring uncommon EGFR mutations were reported.

Results.

In 60 patients (63% female, median age 63 years [range: 30–84 years]), a total of 66 uncommon EGFR mutations including 30 T790M mutations were reported (18.4% and 11%, respectively, of known EGFR mutations within the CUP). Most patients (67%) received afatinib as third- or fourth-line treatment. Median TTF was 3.8 months (range: 0.2 to >24.6 months; p = .244) in patients with uncommon mutations compared with 5.1 months (range: 0.1 to >21.1 months) in patients with common mutations (n = 165). Pronounced activity was observed with E709X mutations (TTF >12 months). No new safety signals were detected.

Conclusion.

Afatinib is clinically active and well tolerated in many TKI-pretreated NSCLC patients harboring uncommon EGFR mutations. Compared with results reported in TKI-naïve patients, activity was also indicated in patients with T790M and exon 20 insertion mutations.

Implications for Practice:

This analysis consists of a large database of non-small cell lung cancer patients with uncommon EGFR mutations who were previously treated with reversible EGFR tyrosine kinase inhibitors. Although indirectly assessed, the results indicate that patients with uncommon EGFR mutations can derive benefit from treatment with the irreversible ErbB family blocker afatinib, even in some cases of tumors harboring resistance-mediating exon 20 mutations. In this study, adverse events were modest and consistent with previous reports on afatinib.     

Nutritional Status,Body Surface,and Low Lean Body Mass/Body Mass Index Are Related to Dose Reduction and Severe Gastrointestinal Toxicity Induced by Afatinib in Patients With Non‐Small Cell Lung Cancer

Background.

The main reason for dose reduction of afatinib is gastrointestinal toxicity (GT). In a phase II study, we analyzed anthropometrical, nutritional, and biochemical factors associated with GT induced by afatinib.

Materials and Methods.

Patients diagnosed with non-small cell lung cancer who progressed to prior chemotherapy received 40 mg of afatinib. Malnutrition was determined by Subjective Global Assessment, and lean body mass (LBM) was determined by computed tomography scan analysis using a pre-established Hounsfield unit threshold. Toxicity was obtained during four cycles by Common Terminology Criteria for Adverse Events.

Results.

Eighty-four patients were enrolled. Afatinib was administered as the second, third, and fourth line of treatment in 54.8%, 38.1%, and 7.12% of patients, respectively. Severe diarrhea, mucositis, and overall severe GT were present in 38.9%, 28.8%, and 57.5%, respectively. Of the patients, 50% developed dose-limiting toxicity (DLT). Patients with malnutrition have higher risk for severe GT. Patients with lower LBM and body mass index developed more DLT (71.4% vs. 18.8%).

Conclusion.

Malnutrition is associated with a higher risk of severe GT induced by afatinib. Determination of nutritional status and body composition are helpful in identifying patients at higher risk of severe GT and could allow initiating treatment with lower doses according to tolerance.

Implications for Practice:

Body composition analysis, specifically lean body mass quantification, and nutritional status assessment are significant clinical variables to take into account when assessing oncological patients. This study on patients with non-small cell lung cancer treated with afatinib showed the important impact that malnutrition and low lean body mass have on the risk for developing dose-limiting toxicity and severe gastrointestinal toxicity. Still more research needs to be done to explore dose adjustment according to lean body mass, especially in drugs that are given at fixed doses, such as afatinib. However, this study presents evidence for the clinical oncologist to have a closer follow-up with malnourished patients and even to consider a lower starting dose until therapeutic dose is achieved.     

蟾毒灵对肝细胞生长因子诱导阿法替尼耐药的逆转作用

目的：探讨蟾毒灵对肝细胞生长因子（ HGF）诱导的阿法替尼耐药肺癌细胞H1975生长的影响,并分析其可能的作用机制。方法采用外源性HGF和重组HGF腺病毒转染内源性HGF诱导的方法建立阿法替尼耐药的肺癌细胞H1975,应用四甲基偶氮唑蓝（ MTT）法检测蟾毒灵、阿法替尼及联合用药对阿法替尼耐药细胞H1975增殖的抑制作用,Transwell实验检测药物对阿法替尼耐药细胞H1975侵袭能力的影响,酶联免疫吸附试验（ ELISA）法检测转染后H1975细胞分泌的HGF水平以及药物对HGF分泌水平的影响,Western blot检测药物干预后EGFR、cMet信号通路及上皮细胞?间质转化（ EMT）相关蛋白的表达。结果 MTT结果显示,在外源性和内源性HGF刺激下,阿法替尼对H1975细胞生长无抑制作用,经蟾毒灵与阿法替尼联合处理后,可明显抑制肿瘤细胞的生长。Transwell实验结果显示,在外源性HGF作用下,阿法替尼组的穿膜细胞数为（118．92±37．29）个;蟾毒灵组的穿膜细胞数为（88．84±19．53）个;阿法替尼与蟾毒灵联合组的穿膜细胞数为（48．98±11．43）个,与阿法替尼组和蟾毒灵组比较,差异均有统计学意义（均P＜0．05）。 ELISA结果显示,H1975／HGF细胞（转染重组HGF腺病毒的H1975细胞）分泌高水平的HGF,蟾毒灵和阿法替尼干预后,H1975／HGF细胞分泌HGF水平差异无统计学意义（P＞0．05）。 Western blot结果显示,蟾毒灵联合阿法替尼能明显下调阿法替尼耐药细胞中 p?EGFR、p?cMet、p?AKT、p?ERK、vimentin 和 snail 蛋白的表达,上调E?cadherin蛋白的表达。结论蟾毒灵联合阿法替尼可显著抑制阿法替尼耐药细胞H1975的增殖,阻止H1975肺癌细胞侵袭;蟾毒灵逆转 HGF 诱导的 H1975肺癌细胞对阿法替尼耐药,可能与阻断cMet／PI3K／AKT、cMet／MAPK／ERK信号通路以及阻止EMT进程有关。     

Melanoma-associated antigen A11 reduces erlotinib and afatinib efficacy in head and neck cancer

Melanoma-associated antigen A (MAGE-A) proteins are members of the cancer/testis antigens (CTA), and the expression of these proteins is almost exclusively limited to malignant cells, making them an attractive treatment target. MAGE-A expression is correlated with poor overall survival in several cancers, including head and neck squamous cell carcinoma (HNSCC). Among others, MAGE-A11 was found to be associated with resistance to different antineoplastic and targeted compounds, such as epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). We searched The Cancer Genome Atlas (TCGA) database with a focus on MAGE-A and found that MAGE-A overexpression is a common event in HNSCC (27.5%). Furthermore, MAGE-A overexpression was correlated with significantly reduced overall survival (35.45 months vs. 64.78 months, P = 0.0173). In particular, MAGE-A11 overexpression was found in 9% of specimens. We then examined MAGE-A11 expression, the efficacy of EGFR and the EGFR mutational status and the effects of the pan-HER (human EGFR) TKIs erlotinib and afatinib in HNSCC cell lines. Next, we used a model of stable MAGE-A11 overexpression to demonstrate that MAGE-A11 impaired the efficacy of erlotinib and afatinib. In summary, our study provides evidence that MAGE-A11 contributes to erlotinib and afatinib resistance in head and neck cancer cell lines.