First-SIGNAL: First-line single-agent iressa versus gemcitabine and cisplatin trial in never-smokers with adenocarcinoma of the lung

Purpose: Gefitinib has shown high response rate and improved progression-free survival (PFS) in never-smokers with lung adenocarcinoma (NSLAs). We compared efficacy of gefitinib with gemcitabine and cisplatin (GP) chemotherapy in this group of patients as first-line therapy. Patients and Methods: In this randomized phase III trial, a total of 313 Korean never-smokers with stage IIIB or IV lung adenocarcinoma, Eastern Cooperative Oncology Group performance status 0 to 2, and adequate organ function were randomly assigned to receive either gefitinib (250 mg daily) or GP chemotherapy (gemcitabine 1,250 mg/m ² on days 1 and 8; cisplatin 80 mg/m ² on day 1 every 3 weeks, for up to nine courses). The primary objective was to demonstrate better overall survival (OS) for gefitinib compared with GP in chemotherapy-naive NSLAs. Results: Three hundred nine patients were analyzed per protocol (gefitinib arm, n = 159; GP arm, n = 150). Gefitinib did not show better OS compared with GP (hazard ratio [HR], 0.932; 95% CI, 0.716 to 1.213; P = .604; median OS, 22.3 v 22.9 months, respectively). The 1-year PFS rates were 16.7% with gefitinib and 2.8% with GP (HR, 1.198; 95% CI, 0.944 to 1.520). Response rates were 55% with gefitinib and 46% with GP (P = .101). Myelosuppression, renal insufficiency, and fatigue were more common in the GP arm, but skin toxicities and liver dysfunction were more common in the gefitinib arm. Two patients (1.3%) in the gefitinib arm developed interstitial lung disease and died. Conclusion: Gefitinib failed to demonstrate superior OS compared with GP as first-line therapy for NSLAs.