1151MO Pathological response is an independent factor of overall survival and disease-free survival after neoadjuvant durvalumab in resectable non-small cell lung cancer (NSCLC) in the IFCT-1601 IONESCO phase II trial

Major pathological response after neoadjuvant cisplatin-based chemotherapy for early-stage NSCLC has been shown to predict survival. This not demonstrated immune checkpoint inhibitors. In IONESCO multicenter phase II trial, 3 cycles of durvalumab were administered in stage IB>4cm–IIIA, non N2 resectable (TNM 8th edition) before surgery. We report here the updated analysis on disease-free survival (DFS) and overall (OS) their association with residual viable tumor cells (RVT). Tissue specimens from patients who underwent complete surgical resection retrospectively evaluated by two pathologists blinded patient outcomes. Specimens reviewed degree pathologic i.e. % RVT primary any involved lymph nodes. The relationship between as a continuous variable outcomes (OS DFS) was analyzed using Cox regression model including characteristics (age, gender, PS, smoking status), histology, PD-L1 proportion score (TPS), procedure. 50 pts included. 46 eligible received durvalumab, 43 operated, 67.4% males, median age, 61 yr; all ECOG PS 0-1; 98% (ex-)smokers; 23 adenocarcinoma, 19 squamous; clinical stages IB/IIA/IIB/IIIA = 5/13/27/1; 15 TPS ≥1%. Median 36.11. OS DFS reached; 18-m OS: 89.1% [95% CI: 75.8-95.3] DFS: 73.7% 58.4-84.1]. multivariate prognostic analysis, increasing value RVT, poorer (HR [95%CI]: 1.05 [1.00-1.10] p=0.04 1.06 [1.01-1.11] p=0.02, respectively). IFCT-1601 trial showed first time that extent inhibitor is an independent factor NSCLC.