Abstract 55P
Background
The landscape of second or further-line treatment on small-cell lung cancer (SCLC) patients is limited, with second-line chemotherapy typically exhibiting diminished efficacy. The ASTRUM-005 study robustly validated the efficacy of first-line serplulimab plus chemotherapy. However, the role of this regimen in subsequent lines of therapy for SCLC remains to be elucidated.
Methods
This study was conducted on adult SCLC patients who underwent second or further-line serplulimab plus chemotherapy from May 2022 to November 2023. The primary outcome was progress-free survival (PFS). Secondary outcomes were objective response rate (ORR), disease control rate (DCR), overall survival (OS), and safety profile. Cox proportional-hazards models were utilized to identify predictors of survival.
Results
A total of 39 patients were eligible for this analysis. As of May 31, 2024, the median follow-up duration since initiating serplulimab was 8.23 months. The mean age was 56.6 ± 10.4 years. The majority were males (87.2%), smokers (79.5%), had ECOG scores of 1 (92.3%), and had stage Ⅳ disease (69.2%). 31 patients (79.5%) achieved ORR events during the first-line phase. Second-line serplulimab was administered to 33 patients (84.6%), and 16 (41.0%) received prior immunotherapy. The median PFS and OS were 4.1 (95%CI 3.1 - 7.2) and 12.0 (95%CI 6.9 - NR) months, respectively. The ORR and DCR were 20.5% (95%CI 9.3 - 36.5) and 64.1% (95%CI 47.2 - 78.8), respectively. Patients who achieved ORR event after initial therapy were more likely to benefit from the subsequent immunochemotherapy, with a median PFS of 10.8 vs. 3.3 months (P = 0.006). While prior immunotherapy didn’t yield a significant effect on survival, patients with such treatment history exhibited a higher ORR (31.3 vs. 13.0%). In multivariate PFS analysis, a significant correlation was found in baseline ProGrp ≥ 300 ng/L (HR 3.0, 95%CI 1.0 - 9.0). Any grade adverse events were reported in 64.1% of patients, and most experienced platelets decreased (23.1%).
Conclusions
Serplulumab-based immunochemotherapy exhibits promising therapeutic efficacy for SCLC patients beyond the initial treatment phase, and further validations are warranted.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Yanrong Guo.
Funding
Shenzhen Xihepu Biomedical Research Institute-Tumour Immunotherapy Project (CCHRPP-ZL-2023-Q-009).
Disclosure
All authors have declared no conflicts of interest.