Updated analysis of SWOG 0023: A randomized phase III trial of gefitinib versus placebo maintenance after definitive chemoradiation followed by docetaxel in patients with locally advanced stage III non-small cell lung cancer
7513 Background: Early clinical studies with gefitinib (G) showed promising efficacy and mild toxicity in patients (pts) with advanced NSCLC. Thus, G was an ideal agent to evaluate in a maintenance setting in stage III disease following definitive treatment. Methods: Untreated pts with stage III NSCLC, a PS of 0–1 and adequate organ function were eligible. Patients received the SWOG 9504 core regimen (cisplatin 50 mg/m2, d1 & 8 plus etoposide 50 mg/m2 day 1–5, every 28 days for 2 cycles with concurrent thoracic radiation, 1.8–2 Gy fractions/day, total dose 61 Gy, followed by 3 cycles of docetaxel 75 mg/m2). Non- progressing pts were randomized to G 250 mg per day or placebo (P) until disease progression, intolerable toxicity or 5 years. The planned sample size was 672, to confer power of 0.89 to detect a 33% increase over the expected median survival of 21 months (one-sided 0.025 level logrank test). Randomization was stratified by stage and histology. Results: Enrollment began in July 2001. An unplanned interim analysis prompted by outside data was conducted in April 2005 and the alternative hypothesis of improved survival was rejected at the 0.0015 level for 243 randomized patients. The study closed and preliminary results were reported (ASCO 2005). Now with a median follow up of 27 months, median survival for the G arm (n=118) was 23 months and was 35 months for the P arm (n=125) (two sided p=0.013). Overall survival for the 571eligible patients was 19 months. ≥ Grade 3 toxicities in the G arm were rash (7%), diarrhea (7%) and pneumonitis (3%). Conclusion: In this unselected population G did not improve survival. Decreased survival was due to cancer not G toxicity. Three year survival estimates will be presented. Molecular studies of the EGFR pathway are underway and will be correlated with outcomes. No significant financial relationships to disclose.