EP.11A.08 Real-world comparative effectiveness in advanced NSCLC and high PD-L1 with 1L immune checkpoint inhibitors ± chemotherapy

The ConcertAI Oncology Database was used to identify patients in the United States with aNSCLC with PD-L1 ≥50% prior to initiating 1L ICI+chemotherapy or ICI monotherapy up to 30 days post-treatment between May 2017 and February 2023. We characterized real-world (rw) response rate (rwRR), overall survival (rwOS), progression-free survival (rwPFS), time to discontinuation (rwTTD), and time to next treatment (rwTTNT). Time-to-event outcomes were assessed using Kaplan-Meier methods after applying inverse probability of treatment weighting (IPTW). Differences in outcomes across patients initiating ICI+chemotherapy or ICI monotherapy were assessed using Cox regression with IPTW to adjust for potential key confounders, including clinical and demographic characteristics; unbalanced covariates were added to the Cox model. Statistical significance was interpreted using 95% CIs.

We identified 1,384 eligible patients, of whom 65% initiated ICI monotherapy and 32% started ICI+chemotherapy. The mean age was 70 years (SD: 9.5) and 51.4% of patients were male; most had adenocarcinoma (63.0%) or squamous cell carcinoma (22.5%). After performing IPTW, key confounding variables were generally well balanced between the ICI monotherapy and ICI+chemotherapy groups. The rwRR was 48.1% (95% CI: 42.4-53.8%) and 39.4% (95% CI: 35.7-43.2%) among patients initiating ICI with and without chemotherapy, respectively, yielding an adjusted odds ratio for response of 1.42 (95% CI: 1.08-1.89). The median rwOS was 19.3 months (95% CI: 15.7-24.4) and 15.9 months (95% CI: 13.5-19.1) among patients who received ICI with and without chemotherapy, respectively, yielding an adjusted hazard ratio (aHR) for death of 0.85 (95% CI: 0.72-1.01). Additionally, ICI+chemotherapy was associated with longer rwPFS with an aHR for disease progression or death of 0.54 (95% CI: 0.42-0.69). No differences were observed in rwTTD and rwTTNT across the 2 groups. See Figure 1 for results.

We observed significantly higher rwRR and rwPFS among patients who received ICI+chemotherapy compared with ICI monotherapy. No significant differences in the rwOS, rwTTD, and rwTTNT between patients on ICI+chemotherapy and ICI monotherapy were observed. Further research is needed to understand patient characteristics associated with benefit from each treatment modality.