Georgina Speake

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.

PURPOSE In the phase III INTEREST trial, 1,466 pretreated patients with advanced non-small cell lung cancer (NSCLC) were randomly assigned to receive gefitinib or docetaxel. As a preplanned analysis, we prospectively analyzed available tumor biopsies to investigate the relationship between biomarkers and clinical outcomes. METHODS Biomarkers included epidermal growth factor receptor (EGFR) copy number by fluorescent in situ hybridization (374 assessable samples), EGFR protein expression by immunohistochemistry (n = 380), and EGFR (n = 297) and KRAS (n = 275) mutations. Results For all biomarker subgroups analyzed, survival was similar for gefitinib and docetaxel, with no statistically significant differences between treatments and no significant treatment by biomarker status interaction tests. EGFR mutation-positive patients had longer progression-free survival (PFS; hazard ratio [HR], 0.16; 95% CI, 0.05 to 0.49; P = .001) and higher objective response rate (ORR; 42.1% v 21.1%; P = .04), and patients with high EGFR copy number had higher ORR (13.0% v 7.4%; P = .04) with gefitinib versus docetaxel. CONCLUSION These biomarkers do not appear to be predictive factors for differential survival between gefitinib and docetaxel in this setting of previously treated patients; however, subsequent treatments may have influenced the survival results. For secondary end points of PFS and ORR, some advantages for gefitinib over docetaxel were seen in EGFR mutation-positive and high EGFR copy number patients. There was no statistically significant difference between gefitinib and docetaxel in biomarker-negative patients. This suggests gefitinib can provide similar overall survival to docetaxel in patients across a broad range of clinical subgroups and that EGFR biomarkers such as mutation status may additionally identify which patients are likely to gain greatest PFS and ORR benefit from gefitinib.

PURPOSE: To compare survival in patients with recurrent or metastatic squamous cell carcinoma of the head and neck (SCCHN) treated with gefitinib 250 or 500 mg/day or standard methotrexate. PATIENTS AND METHODS: Four hundred eighty-six patients with recurrent SCCHN were randomly assigned to oral gefitinib 250 mg/day, gefitinib 500 mg/day, or methotrexate 40 mg/m(2) intravenously weekly. Primary end point was overall survival, secondary end points were objective response rate (ORR), safety, symptom improvement, and quality of life (QOL). Exploratory end points included association of efficacy with epidermal growth factor receptor gene copy number and other biomarkers. RESULTS: Neither gefitinib 250 nor 500 mg/day improved overall survival compared with methotrexate (hazard ratio [HR], 1.22; 95% CI, 0.95 to 1.57; P = .12; and HR, 1.12; 95% CI, 0.87 to 1.43; P = .39, respectively). In the gefitinib 250 mg/day, 500 mg/day, and methotrexate groups, respectively, median overall survival was 5.6, 6.0, and 6.7 months; ORRs (Response Evaluation Criteria in Solid Tumors) were 2.7%, 7.6% and 3.9%, with no statistically significant difference between either gefitinib arm and methotrexate. No unexpected adverse events were observed, except for tumor hemorrhage-type events with gefitinib (8.9%, gefitinib 250 mg/day; 11.4%, gefitinib 500 mg/day; 1.9%, methotrexate). QOL improvement rates (Functional Assessment of Cancer Therapy-Head & Neck total score) were 13.4%, 18.0%, and 6.0% for gefitinib 250 mg/day, 500 mg/day, and methotrexate, respectively. CONCLUSION: In patients with recurrent or metastatic SCCHN, while responses with gefitinib were seen, neither gefitinib 250 nor 500 mg/day improved overall survival compared with methotrexate. With the exception of tumor hemorrhage-type events with gefitinib, the adverse event profiles were generally consistent with those previously observed.

AIMS: Activating mutations in the gene encoding epidermal growth factor receptor (EGFR) can confer sensitivity to EGFR tyrosine kinase inhibitors such as gefitinib in patients with advanced non-small-cell lung cancer. Testing for mutations in EGFR is therefore an important step in the treatment-decision pathway. We reviewed reported methods for EGFR mutation testing in patients with lung cancer, initially focusing on studies involving standard tumour tissue samples. We also evaluated data on the use of cytology samples in order to determine their suitability for EGFR mutation analysis. METHODS: We searched the MEDLINE database for studies reporting on EGFR mutation testing methods in patients with lung cancer. RESULTS: Various methods have been investigated as potential alternatives to the historical standard for EGFR mutation testing, direct DNA sequencing. Many of these are targeted methods that specifically detect the most common EGFR mutations. The development of targeted mutation testing methods and commercially available test kits has enabled sensitive, rapid and robust analysis of clinical samples. The use of screening methods, subsequent to sample micro dissection, has also ensured that identification of more rare, uncommon mutations is now feasible. Cytology samples including fine needle aspirate and pleural effusion can be used successfully to determine EGFR mutation status provided that sensitive testing methods are employed. CONCLUSIONS: Several different testing methods offer a more sensitive alternative to direct sequencing for the detection of common EGFR mutations. Evidence published to date suggests cytology samples are viable alternatives for mutation testing when tumour tissue samples are not available.

PURPOSE: This phase II, open-label, parallel-group study compared gefitinib with vinorelbine in chemotherapy-naïve elderly patients with advanced non-small-cell lung cancer (NSCLC). METHODS: Chemotherapy-naïve patients (age >or= 70 years) were randomly assigned to gefitinib (250 mg/d orally) or vinorelbine (30 mg/m(2) infusion on days 1 and 8 of a 21-day cycle). The primary end point was progression-free survival (PFS). Secondary end points were overall survival (OS), objective response rate (ORR), quality of life (QOL), pulmonary symptom improvement (PSI), and tolerability. Exploratory end points included epidermal growth factor receptor (EGFR) gene copy number by fluorescent in situ hybridization (FISH). RESULTS: Patients were randomly assigned to gefitinib (n = 97) or to vinorelbine (n = 99). Hazard ratios (HR; gefitinib v vinorelbine) were 1.19 (95% CI, 0.85 to 1.65) for PFS and 0.98 (95% CI, 0.66 to 1.47) for OS. ORR and disease control rates were 3.1% (95% CI, 0.6 to 8.8) and 43.3% (for gefitinib) and 5.1% (95% CI, 1.7 to 11.4) and 53.5% (for vinorelbine), respectively. Overall QOL improvement and PSI rates were 24.3% and 36.6% (for gefitinib) and 10.9% and 31.0% (for vinorelbine), respectively. In the 54 patients who were EGFR FISH-positive, HRs were 3.13 (95% CI, 1.45 to 6.76) for PFS and 2.88 (95% CI, 1.21 to 6.83) for OS. There were fewer treatment-related grade 3 to 5 adverse events with gefitinib (12.8%) than with vinorelbine (41.7%). CONCLUSION: There was no statistical difference between gefitinib and vinorelbine in efficacy in chemotherapy-naïve, unselected elderly patients with advanced NSCLC, but there was better tolerability with gefitinib. Individuals who were EGFR FISH-positive benefited more from vinorelbine than from gefitinib; this unexpected finding requires further study.