7529 Purpose: This analysis was conducted to address the potential antitumor effect of amifostine (AM) in NSCLC patients enrolled on RTOG-9801. The long-term survival results of RTOG-9801 are presented here. Methods: 243 patients (pts) with stage II/IIIAB NSCLC received induction paclitaxel (P) 225 mg/m2IV days 1, 22 and carboplatin (C) AUC 6 days 1, 22 and then concurrent weekly P (50 mg/m2) and C (AUC 2) and HRT (69.6 Gy at 1.2 Gy BID). Pts were randomly assigned to AM 500 mg IV 4x/week or no-AM during chemoradiation. Treatment differences for overall and disease-free survival (OS & DFS) were analyzed with the log-rank test; Gray's test was used for time to progression (TTP). Results: 118 pts were randomly assigned to receive AM and 121 to no-AM (4 pts were ineligible). The median follow-up for pts still alive is 52.3 months (mo) for the AM-arm and 58.3 mo for the no-AM arm (16.6 vs 17.9 for all pts). There are no significant differences in OS, DFS or TTP between arms. The median survival, 3-yr, and 5-yr OS are 17.1 mo, 27% and 17% (AM-arm) vs 18.4 mo, 28% and 16% (no-AM arm) (p=0.97). Grade 3/4/5 late-RT toxicities are similar (11%/3%/2% AM-arm vs 14%/4%/2% no-AM arm). Conclusion: While an earlier publication reported that amifostine did not reduce objective measures of severe esophagitis in RTOG-9801, patient-reported outcome analyses suggested a possible advantage to AM with decreased pain and swallowing symptoms (J Clin Oncol 23:2145–2154, 2005). This long-term follow-up analysis on survival shows no evidence of tumor radioprotection due to amifostine. The promising 5-yr OS suggests that induction paclitaxel/carboplatin (P/C) followed by concurrent RT and weekly low-dose P/C is comparable to other regimens using cisplatin doublets at higher dosages every 3–4 weeks. Research supported by NCI and Medimmune Oncology. No significant financial relationships to disclose.