Long-Term Survival Outcomes With First-Line Nivolumab Plus Ipilimumab-Based Treatment in Patients With Metastatic NSCLC and Tumor Programmed Death-Ligand 1 Lower Than 1%: A Pooled Analysis.

Introduction: Nivolumab plus ipilimumab-based treatment regimens have shown long-term, durable efficacy benefits in patients with metastatic NSCLC. Here we report clinical outcomes from a pooled analysis of patients with metastatic NSCLC and tumor programmed death-ligand 1 (PD-L1) lower than 1% treated with first-line nivolumab plus ipilimumab with or without two cycles of chemotherapy versus up to four cycles of chemotherapy in the randomized phase 3 CheckMate 227 and CheckMate 9LA studies.

Methods: Patients were aged 18 years or older and had stage IV or recurrent NSCLC with no sensitizing EGFR/ALK alterations. Assessments included overall survival (OS), progression-free survival (PFS), objective response rate, duration of response, and safety.

Results: In patients with tumor PD-L1 lower than 1% in the nivolumab plus ipilimumab with or without chemotherapy (n = 322) versus chemotherapy (n = 315) arms, median OS was 17.4 versus 11.3 months, respectively, (hazard ratio [HR] = 0.64, 95% confidence interval [CI]: 0.54-0.76; 5-y OS rate, 20% versus 7%) at a median follow-up of 73.7 months. The OS benefit was observed across key subgroups, including difficult-to-treat populations such as those with baseline brain metastases (HR = 0.44, 95% CI: 0.26-0.75) or squamous NSCLC (HR = 0.51, 95% CI: 0.36-0.72). In the overall pooled population, the median PFS was 5.4 versus 4.9 months (HR = 0.72, 95% CI: 0.60-0.87; 5-y PFS rate, 9% versus 2%), the objective response rate was 29% versus 22%, and the median duration of response was 18.0 versus 4.6 months. No new safety signals were observed.

Conclusion: Nivolumab plus ipilimumab with or without chemotherapy provides a long-term, durable clinical benefit in patients with metastatic NSCLC and tumor PD-L1 lower than 1%, supporting the use of this strategy as a first-line treatment option in this population with high unmet need.

Clinical trial registrations: NCT02477826, NCT03215706.