Abstract 35P
Background
Despite numerous randomized clinical trials (RCTs) on cancer vaccines, systematic evaluations of their efficacy and safety for patients with advanced non-small cell lung cancer (NSCLC) following first-line therapy remain lacking.
Methods
In this systematic review and meta-analysis (CRD42024568178), PubMed, Cochrane Library, and Embase databases were searched from inception up to December 27, 2024. Published phase II or III RCTs reporting survival outcomes in advanced or metastatic NSCLC patients who received vaccine therapy after first-line therapy were included. Data were independently extracted by two reviewers. The primary outcome was overall survival (OS), with progression-free survival (PFS) as secondary outcome. Treatment-related adverse events (TRAEs) were the major safety outcome.
Results
Eleven RCTs comprising 3228 patients were included, without high risk of bias. The included studies involved employing cancer vaccines as first-line maintenance therapy, second- or third-line therapy. In general, Cancer vaccines associated with improved OS (HR=0.85, 95% CI, 0.78–0.92, P < 0.001) but did not significantly improve PFS (HR=0.91, 95% CI, 0.79–1.05, P=0.195). Subgroup analyses indicated better OS for patients with ECOG=1, squamous cell carcinoma, stable disease after first-line therapy, stage IV, and smoking history. Squamous cell carcinoma responded better to vaccine therapy than adenocarcinoma. The pooled OR for TRAEs was 1.5 (95% CI, 0.63–3.61, P=0.361). Exploratory analysis indicated that immune response to cancer vaccines may serve as a predictive biomarker for vaccines effect. Besides, consistent efficacy and safety results were obtained when the meta-analysis was specific to first-line maintenance therapy based on seven trials.
Conclusions
This meta-analysis demonstrated the clinical efficacy and safety of cancer vaccines in advanced NSCLC patients after first-line therapy, especially in those with squamous cell carcinoma. Immune response was identified as a predictive biomarker for vaccines effect. This study provides the state-of-the-art evidence for the clinical application of cancer vaccines in advanced NSCLC patients.
Legal entity responsible for the study
The authors.
Funding
Beijing Nova Program; National Key R&D Program of China; Research Unit of Intelligence Diagnosis and Treatment in Early non-small Cell Lung Cancer, Chinese Academy of Medical Sciences; National Natural Science Foundation of China; Peking University People’s Hospital Research and Development Founds.
Disclosure
All authors have declared no conflicts of interest.