Previous, uncontrolled studies have suggested that first-line treatment with gefitinib would be efficacious in selected patients with non–small-cell lung cancer. In this phase 3, open-label study, we randomly assigned previously untreated patients in East Asia who had advanced pulmonary adenocarcinoma and who were nonsmokers or former light smokers to receive gefitinib (250 mg per day) (609 patients) or carboplatin (at a dose calculated to produce an area under the curve of 5 or 6 mg per milliliter per minute) plus paclitaxel (200 mg per square meter of body-surface area) (608 patients). The primary end point was progression-free survival. The 12-month rates of progression-free survival were 24.9% with gefitinib and 6.7% with carboplatin–paclitaxel. The study met its primary objective of showing the noninferiority of gefitinib and also showed its superiority, as compared with carboplatin–paclitaxel, with respect to progression-free survival in the intention-to-treat population (hazard ratio for progression or death, 0.74; 95% confidence interval [CI], 0.65 to 0.85; P<0.001). In the subgroup of 261 patients who were positive for the epidermal growth factor receptor gene (EGFR) mutation, progression-free survival was significantly longer among those who received gefitinib than among those who received carboplatin–paclitaxel (hazard ratio for progression or death, 0.48; 95% CI, 0.36 to 0.64; P<0.001), whereas in the subgroup of 176 patients who were negative for the mutation, progression-free survival was significantly longer among those who received carboplatin–paclitaxel (hazard ratio for progression or death with gefitinib, 2.85; 95% CI, 2.05 to 3.98; P<0.001). The most common adverse events were rash or acne (in 66.2% of patients) and diarrhea (46.6%) in the gefitinib group and neurotoxic effects (69.9%), neutropenia (67.1%), and alopecia (58.4%) in the carboplatin–paclitaxel group. Gefitinib is superior to carboplatin–paclitaxel as an initial treatment for pulmonary adenocarcinoma among nonsmokers or former light smokers in East Asia. The presence in the tumor of a mutation of the EGFR gene is a strong predictor of a better outcome with gefitinib. (ClinicalTrials.gov number, NCT00322452.)

Purpose: The LUX-Lung 3 study investigated the efficacy of chemotherapy compared with afatinib, a selective, orally bioavailable ErbB family blocker that irreversibly blocks signaling from epidermal growth factor receptor (EGFR/ErbB1), human epidermal growth factor receptor 2 (HER2/ErbB2), and ErbB4 and has wide-spectrum preclinical activity against EGFR mutations. A phase II study of afatinib in EGFR mutation–positive lung adenocarcinoma demonstrated high response rates and progression-free survival (PFS). Patients and Methods: In this phase III study, eligible patients with stage IIIB/IV lung adenocarcinoma were screened for EGFR mutations. Mutation-positive patients were stratified by mutation type (exon 19 deletion, L858R, or other) and race (Asian or non-Asian) before two-to-one random assignment to 40 mg afatinib per day or up to six cycles of cisplatin plus pemetrexed chemotherapy at standard doses every 21 days. The primary end point was PFS by independent review. Secondary end points included tumor response, overall survival, adverse events, and patient-reported outcomes (PROs). Results: A total of 1,269 patients were screened, and 345 were randomly assigned to treatment. Median PFS was 11.1 months for afatinib and 6.9 months for chemotherapy (hazard ratio [HR], 0.58; 95% CI, 0.43 to 0.78; P = .001). Median PFS among those with exon 19 deletions and L858R EGFR mutations (n = 308) was 13.6 months for afatinib and 6.9 months for chemotherapy (HR, 0.47; 95% CI, 0.34 to 0.65; P = .001). The most common treatment-related adverse events were diarrhea, rash/acne, and stomatitis for afatinib and nausea, fatigue, and decreased appetite for chemotherapy. PROs favored afatinib, with better control of cough, dyspnea, and pain. Conclusion: Afatinib is associated with prolongation of PFS when compared with standard doublet chemotherapy in patients with advanced lung adenocarcinoma and EGFR mutations.

The EGFR T790M mutation is the most common mechanism of drug resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors in patients who have lung cancer with an EGFR mutation (EGFR-mutated lung cancer). In preclinical models, the EGFR inhibitor AZD9291 has been shown to be effective against both EGFR tyrosine kinase inhibitor–sensitizing and T790M resistance mutations. We administered AZD9291 at doses of 20 to 240 mg once daily in patients with advanced lung cancer who had radiologically documented disease progression after previous treatment with EGFR tyrosine kinase inhibitors. The study included dose-escalation cohorts and dose-expansion cohorts. In the expansion cohorts, prestudy tumor biopsies were required for central determination of EGFR T790M status. Patients were assessed for safety, pharmacokinetics, and efficacy. A total of 253 patients were treated. Among 31 patients enrolled in the dose-escalation cohorts, no dose-limiting toxic effects occurred at the doses evaluated. An additional 222 patients were treated in five expansion cohorts. The most common all-cause adverse events were diarrhea, rash, nausea, and decreased appetite. The overall objective tumor response rate was 51% (95% confidence interval [CI], 45 to 58). Among 127 patients with centrally confirmed EGFR T790M who could be evaluated for response, the response rate was 61% (95% CI, 52 to 70). In contrast, among 61 patients without centrally detectable EGFR T790M who could be evaluated for response, the response rate was 21% (95% CI, 12 to 34). The median progression-free survival was 9.6 months (95% CI, 8.3 to not reached) in EGFR T790M–positive patients and 2.8 months (95% CI, 2.1 to 4.3) in EGFR T790M–negative patients. AZD9291 was highly active in patients with lung cancer with the EGFR T790M mutation who had had disease progression during prior therapy with EGFR tyrosine kinase inhibitors. (Funded by AstraZeneca; ClinicalTrials.gov number, NCT01802632.)

In human lung adenocarcinomas harboring EGFR mutations, a second-site point mutation that substitutes methionine for threonine at position 790 (T790M) is associated with approximately half of cases of acquired resistance to the EGFR kinase inhibitors, gefitinib and erlotinib. To identify other potential mechanisms that contribute to disease progression, we used array-based comparative genomic hybridization (aCGH) to compare genomic profiles of EGFR mutant tumors from untreated patients with those from patients with acquired resistance. Among three loci demonstrating recurrent copy number alterations (CNAs) specific to the acquired resistance set, one contained the MET proto-oncogene. Collectively, analysis of tumor samples from multiple independent patient cohorts revealed that MET was amplified in tumors from 9 of 43 (21%) patients with acquired resistance but in only two tumors from 62 untreated patients (3%) ( P = 0.007, Fisher's Exact test). Among 10 resistant tumors from the nine patients with MET amplification, 4 also harbored the EGFR ^T790M mutation. We also found that an existing EGFR mutant lung adenocarcinoma cell line, NCI-H820, harbors MET amplification in addition to a drug-sensitive EGFR mutation and the T790M change. Growth inhibition studies demonstrate that these cells are resistant to both erlotinib and an irreversible EGFR inhibitor (CL-387,785) but sensitive to a multikinase inhibitor (XL880) with potent activity against MET. Taken together, these data suggest that MET amplification occurs independently of EGFR ^T790M mutations and that MET may be a clinically relevant therapeutic target for some patients with acquired resistance to gefitinib or erlotinib.

Purpose: The results of the Iressa Pan-Asia Study (IPASS), which compared gefitinib and carboplatin/paclitaxel in previously untreated never-smokers and light ex-smokers with advanced pulmonary adenocarcinoma were published previously. This report presents overall survival (OS) and efficacy according to epidermal growth factor receptor (EGFR) biomarker status. Patients and Methods: In all, 1,217 patients were randomly assigned. Biomarkers analyzed were EGFR mutation (amplification mutation refractory system; 437 patients evaluable), EGFR gene copy number (fluorescent in situ hybridization; 406 patients evaluable), and EGFR protein expression (immunohistochemistry; 365 patients evaluable). OS analysis was performed at 78% maturity. A Cox proportional hazards model was used to assess biomarker status by randomly assigned treatment interactions for progression-free survival (PFS) and OS. Results: OS (954 deaths) was similar for gefitinib and carboplatin/paclitaxel with no significant difference between treatments overall (hazard ratio [HR], 0.90; 95% CI, 0.79 to 1.02; P = .109) or in EGFR mutation–positive (HR, 1.00; 95% CI, 0.76 to 1.33; P = .990) or EGFR mutation–negative (HR, 1.18; 95% CI, 0.86 to 1.63; P = .309; treatment by EGFR mutation interaction P = .480) subgroups. A high proportion (64.3%) of EGFR mutation–positive patients randomly assigned to carboplatin/paclitaxel received subsequent EGFR tyrosine kinase inhibitors. PFS was significantly longer with gefitinib for patients whose tumors had both high EGFR gene copy number and EGFR mutation (HR, 0.48; 95% CI, 0.34 to 0.67) but significantly shorter when high EGFR gene copy number was not accompanied by EGFR mutation (HR, 3.85; 95% CI, 2.09 to 7.09). Conclusion: EGFR mutations are the strongest predictive biomarker for PFS and tumor response to first-line gefitinib versus carboplatin/paclitaxel. The predictive value of EGFR gene copy number was driven by coexisting EGFR mutation (post hoc analysis). Treatment-related differences observed for PFS in the EGFR mutation–positive subgroup were not apparent for OS. OS results were likely confounded by the high proportion of patients crossing over to the alternative treatment.