RT Journal Article SR Electronic T1 801 Risk-benefit ratio in immunotherapy (IO) with or without chemotherapy (CT) according to PD-L1 expression: a model-based approach to inform treatment decisions in metastatic non-small cell lung cancer JF Journal for ImmunoTherapy of Cancer JO J Immunother Cancer FD BMJ Publishing Group Ltd SP A899 OP A900 DO 10.1136/jitc-2023-SITC2023.0801 VO 11 IS Suppl 1 A1 Zhao, Molly A1 Mangal, Naveen A1 Zierhut, Matthew L A1 Witjes, Han A1 Chen, Ting A1 Dang, Thao A1 Ruiz, Ana A1 Girish, Sandhya A1 Kasichayanula, Sreeneeranj YR 2023 UL http://jitc.bmj.com/content/11/Suppl_1/A899.abstract AB Background Anti-programmed death-(ligand)1 (PD-[L]1) therapies, either as monotherapy or in combination, have demonstrated remarkable efficacy in first-line (1L) treatment for metastatic non-small cell lung cancer (mNSCLC). Treatment decisions are often influenced by multiple factors, e.g., PD-L1 expression level or adverse event (AE) profile. Model-based meta-analyses (MBMA) of safety and efficacy can evaluate clinical risk-benefit ratio among FDA-approved IO therapies and inform treatment decisions in mNSCLC patients.Methods MBMA of median overall survival (mOS) and treatment-related AEs Grade 3–5 (TRAEs Gr3+) were conducted using a curated database containing results from both randomized controlled and single-arm studies (published from 2015 to 2022) with FDA-approved (as of January 2023) IO-based treatments in mNSCLC patients. The analysis dataset comprised mOS and TRAEs Gr3+ results from 49 and 45 studies, and represented 17,918 and 19,238 patients, respectively. The mOS dataset included 34, 28, and 11 studies containing treatment of IO monotherapy, CT, and IO+CT, respectively. In the TRAE analysis, there were 33, 23, and 12 studies containing treatment of IO monotherapy, CT, and IO+CT, respectively. Analyses of endpoints utilized linear models in appropriately transformed domains (i.e., log for mOS, logit for TRAE Gr3+) and data were weighted by standard error of the outcome. After accounting for differential outcomes from specific treatments, potential impact of baseline characteristics (e.g., PD-L1 expression, line of therapy, ECOG PS, sex, histology, and geography/race) on the risk and benefit was evaluated. Models included between-study random effects and all covariates were additive.Results Regardless of specific IO agent or PD-L1 expression level, fewer patients experienced TRAEs Gr3+ with IO alone (14% [6.2–29]) compared to CT alone (39% [21–61]) or IO+CT (48% [27–70]). Among patients with PD-L1 expression ³50%, mOS was comparable for IO with or without CT (figure 1A,B). In patients with PD-L1 expression <1% (figure 1C,D), therapeutic benefit was higher for IO+CT (16 months [13–19]) than IO alone (12 months [10–15]), justifying the choice of IO+CT in this patient population despite higher TRAEs than IO alone. table 1 summarizes all model parameter estimates, including influential covariates on mOS. No clinically meaningful covariates were identified for TRAEs Gr3+.Conclusions This MBMA evaluates the risk-benefit ratio and provides quantitative insight into the therapeutic utility of IO agents. Our findings are consistent with treatment guidelines for 1L patients with mNSCLC, highlighting the potential utility of a quantitative model-based approach to strengthen clinical recommendations and to facilitate decision making.Abstract 801 Figure 1 Model predicated mOS and TRAE Gr3+ for first-line, non-Asian, mNSCLC patient populationView this table:Abstract 801 Table 1 Model Parameter Estimates with 95% Confidence Intervals