Abstract CT097: Associations between percent residual viable tumor (%RVT) and efficacy with perioperative nivolumab (NIVO) for resectable NSCLC in CheckMate 77T

Abstract

Abstract Background: In CheckMate 816, lower %RVT in primary tumor (PT) and lymph node (LN) after neoadjuvant (neoadj) NIVO + chemo correlated with improved EFS in patients (pts) with resectable NSCLC. To further evaluate %RVT as a surrogate for EFS, we report an exploratory analysis of efficacy with adjuvant (adj) NIVO after neoadj treatment (tx) by LN involvement, nodal (N) status, and %RVT in PT and LN in CheckMate 77T. Methods: Pts with resectable stage IIA-IIIB NSCLC were randomized to neoadj NIVO + chemo Q3W (up to 4 cycles [cyc]) followed by adj NIVO Q4W (up to 13 cyc) or neoadj placebo (PBO) + chemo Q3W (up to 4 cyc) followed by adj PBO Q4W (up to 13 cyc). Primary endpoint: EFS per BICR. This analysis, which included pts with pathologically evaluable samples who had definitive surgery and ≥ 1 adj tx dose, assessed EFS by LN involvement, N status, %RVT in PT and LN, and associations between %RVT and EFS per time-dependent ROC curve analysis. Results: BL characteristics were similar between tx arms (NIVO, 123; PBO, 134; median f/u, 33.3 mo). NIVO improved EFS v PBO regardless of LN involvement or N status (Table). A higher proportion of pts treated with NIVO had 0% RVT in PT and/or LN v PBO (52% v 20%). In pts with LN involvement, 2-y EFS rates with NIVO were higher in pts with 0% RVT in both PT and LN (90%) or 0% RVT in PT or LN (85%) v > 0% RVT in both PT and LN (76%). Area under the ROC curve for %RVT-PT in pts with PT-only disease was 0.83. 2-y EFS rates with NIVO were 94%, 77%, and 50% in pts with 0-5%, > 5-80%, and > 80% RVT-PT, respectively; similar results were seen in all pts with pathologically evaluable samples whether they received adj tx or not. Conclusions: In this exploratory analysis, NIVO improved EFS v PBO, particularly in pts with LN involvement and regardless of N status. %RVT also associated with EFS in a continuous manner, supporting %RVT as a surrogate for EFS and highlighting its prognostic value in pts who receive perioperative NIVO. Citation Format: Julie Stein Deutsch, Ashley Cimino-Mathews, Elizabeth Thompson, Edward Gabrielson, Peter Illei, Jaroslaw Jedrych, Ezra Baraban, Alex S. Baras, Mariano Provencio Pulla, Tina Cascone, Jonathan D. Spicer, Mark M. Awad, Fumihiro Tanaka, Jie He, Shun Lu, Cinthya Coronado Erdmann, Vipul Devas, Sumeena Bhatia, Janis M. Taube. Associations between percent residual viable tumor (%RVT) and efficacy with perioperative nivolumab (NIVO) for resectable NSCLC in CheckMate 77T [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_2):Abstract nr CT097.