Abstract 9000

Outcomes of anti-PD-(L)1 therapy with or without chemotherapy (chemo) for first-line (1L) treatment of advanced non-small cell lung cancer (NSCLC) with PD-L1 score ≥50%: FDA pooled analysis.

Background: FDA-approved 1L treatment options for patients with PD-L1-high advanced NSCLC (PD-L1 score ≥50%) include IO ± chemo (± anti-angiogenics) but it is unclear if chemo substantially improves efficacy outcomes when added to IO in this patient population. 

Methods: Data was pooled from 12 randomized controlled trials that investigated anti-PD-(L)1 regimens ± chemo for the 1L treatment of patients with advanced NSCLC. PD-L1 score was defined as the proportion of tumor cells stained by the assay and analysis was conducted for patients with tumor PD-L1 score ≥50%. OS, PFS, and ORR were compared between chemo-IO and IO alone via a pooled analysis. Median survival times were estimated using Kaplan-Meier methods. Hazard ratios were estimated using Cox proportional hazards models stratified by trial; odds ratios were estimated using a logistic regression model with trial as a covariate. All analyses were adjusted for age, sex, race, ECOG, histology and smoking status. 

Results: A total of 3,189 patients with NSCLC and PD-L1 score ≥50% were identified for this analysis. Baseline characteristics were: 38% ages 65-74 years and 11% ages ≥75 years; 69% male; 80% White; 66% ECOG ≥1; and 89% former/current smokers. Median OS in the pooled chemo-IO (N=455) and IO-only (N=1,298) arms was 25.0 vs 20.9 months (HR 0.82; 95% CI: 0.62, 1.08); median PFS was 9.6 vs 7.1 months, respectively (HR 0.69; 95% CI: 0.55, 0.87). ORR was higher with chemo-IO than with IO alone (61% vs 43%; Odds ratio 1.2, 95% CI: 1.1, 1.3). 

Conclusions: This exploratory, hypothesis-generating pooled analysis suggests that most subgroups of patients with advanced NSCLC with PD-L1 score ≥50% receiving FDA-approved chemo-IO regimens may have OS and PFS outcomes that are comparable with or better than IO-only regimens. Patients ≥75 years of age receiving chemo-IO may not have improved outcomes over IO. These results support shared decision-making that balances potential benefits and risks of adding chemo to IO regimens based on patient factors that may impact tolerability.

Research Sponsor: None.