Serplulimab Plus Chemotherapy Shows Sustained Survival Benefit in Extensive-Stage Small Cell Lung Cancer
Clinical Summary:
- Design/Population: This double-blind, phase 3 trial evaluated serplulimab plus carboplatin and etoposide in patients with previously untreated extensive-stage small cell lung cancer.
- Key Outcomes: At extended follow-up, serplulimab plus chemotherapy significantly improved median overall survival and increased overall survival rates, with no new safety signals and favorable patient-reported outcomes.
- Clinical Relevance: These findings support serplulimab plus platinum-etoposide chemotherapy as a first-line standard-of-care option for patients with extensive-stage small cell lung cancer.
Updated findings from the phase 3 ASTRUM-005 trial showed that adding serplulimab to carboplatin and etoposide continued to improve long-term survival in patients with previously untreated extensive-stage small cell lung cancer (ES-SCLC).
Prior results demonstrated “substantial survival benefit from adding serplulimab to chemotherapy for previously untreated ES-SCLC… however, the long-term outcomes are unclear,” stated Jingjing Liu, MD, Jilin Cancer Hospital, Jilin, China, and coauthors.
In this double-blind trial, 585 patients with histologically or cytologically confirmed ES-SCLC who underwent no prior lines of systemic therapy were randomized 2:1 to receive either 4.5 mg/kg of intravenous serplulimab (n = 389) or placebo (n = 196) with up to 4 cycles of carboplatin and etoposide administered once every 3 weeks. The primary end point was overall survival (OS). Secondary end points included safety and patient-reported outcomes.
At a median follow-up of 42.4 months, median OS was 15.8 months in the serplulimab arm and 11.1 months in the placebo arm, which corresponded to a 40% reduction in the risk of death (hazard ratio [HR], 0.60; 95% confidence interval [CI], 0.49 to 0.73; P < .001). The 4-year OS rates were 21.9% and 7.2%, respectively.
Grade ≥3 serplulimab-related or placebo-related treatment-emergent adverse events were reported in in 136 patients in the serplulimab arm and 57 patients in the placebo arm. Patient-reported outcomes demonstrated consistent trends towards improved overall health, dyspnea, and pain in both treatment groups, with faster recovery from alopecia observed in patients enrolled in the serplulimab arm.
“This secondary analysis of a randomized clinical trial demonstrated long-term benefit from adding serplulimab to chemotherapy for previously untreated patients with ES-SCLC, supporting this therapy as a first-line standard of care for this patient population,” concluded Dr Liu and coauthors.
Source:
Liu J, Han L, Wu L, et al. First-line serplulimab in extensive-stage small cell lung cancer. JAMA Oncol. Published online: June 4, 2026. doi: 10.1001/jamaoncol.2026.1645
