Final analysis of overall survival (OS) in the IPASS, an international multicenter phase III study on gefitinib and carboplatin/paclitaxel for treatment-naïve NSCLC patients

IPASS (Iressa Pan-Asia Study) is a phase III study conducted in East Asia that compared gefit-inib and carboplatin-paclitaxel among nonsmokers or former light smokers with pulmonary adenocarcinoma previously untreated with chemotherapy. It has already been reported that the primary endpoint progression-free survival (PFS), was significantly longer in the gefitinib group. Subset analysis via biomarkers has also been reported, whereby the gefitinib group in the epidermal growth factor receptor (EGFR) gene mutation subgroup showed a significantly greater extension in PFS and the gefitinib group in the mutation negative subgroup, a significantly shorter PFS. The final report on overall survival (OS) was reported at European Society for Medical Oncology (ESMO) congress in 2010, with the same content reported at a symposium in the Japan Lung Cancer Society Annual Meeting. The overall analysis showed an OS of 18.8 months in the gefitinib group and 17.4 months, chemotherapy group (HR = 0.90), indicating no difference between the two groups. Subset analysis respectively showed the median survival in the gefitinib and chemotherapy groups in the EGFR mutation positive subset to be 21.6 and 21.9 months, while the respective median survival in the negative cases was 11.2 and 12.7 months. These results indicate longer survival in any group among the EGFR mutation positive cases, but no difference in OS by treatment regardless of EGFR mutation status.