THE ADDITION of nivolumab to platinum-etoposide chemotherapy improved both progression-free and overall survival in patients with extensive-stage small cell lung cancer (ES-SCLC), according to results from the randomized Phase II ECOG-ACRIN EA5161 trial.
In this study, patients with untreated ES-SCLC and good performance status were randomized to receive standard cisplatin or carboplatin with etoposide (PE) alone or in combination with nivolumab. The investigational arm continued on maintenance nivolumab for up to two years, while the control arm received observation following chemotherapy completion. The primary endpoint was progression-free survival, with secondary endpoints including overall survival, objective response rate, and safety.
A total of 160 patients were enrolled, with 144 included in the primary analysis. The median progression-free survival was 5.5 months with the addition of nivolumab compared to 4.9 months with chemotherapy alone. Although this difference did not reach conventional statistical significance (HR: 0.78; p=0.083), the overall survival analysis showed a notable advantage. Median overall survival was 11.2 months in the nivolumab group compared to 8.1 months in the chemotherapy-only group (HR: 0.71; p=0.059).
Importantly, the combination regimen did not reveal any new safety concerns, suggesting that nivolumab can be safely integrated with standard platinum-etoposide chemotherapy in this population. While the progression-free survival improvement was modest, the overall survival benefit indicates that the addition of immunotherapy may meaningfully extend outcomes in this aggressive disease setting.
These findings highlight the potential for immunotherapy-based regimens to reshape frontline management of ES-SCLC, a disease historically marked by limited treatment advances and poor prognosis.
Reference:
Leal TA et al. Randomized phase II clinical trial of cisplatin/carboplatin and etoposide (PE) alone or in combination with nivolumab as frontline therapy for extensive-stage small cell lung cancer (ES-SCLC): ECOG-ACRIN EA5161. Cancer. 2025;131(12):e35938.