Antibody-drug conjugates therapy for triple-negative breast cancer: a systematic review and meta-analysis

Purpose This systematic review and meta-analysis aimed to compare the efficacy and safety of antibody-drug conjugates (ADCs) vs. conventional chemotherapy in patients with triple-negative breast cancer (TNBC) and to provide evidence for clinical decision-making and guideline development. Methods We systematically searched PubMed, Embase, and Cochrane Library and extracted data including hazard ratio (HR) and 95% confidence interval (CI) for progression-free survival (PFS) and overall survival (OS), odds ratio (OR) for safety, and objective response rate (ORR). Results This study ultimately included 6 articles (5 dedicated RCTs for TNBC and 1 exploratory analysis of an HR-negative/HER2-low subgroup from the DESTINY-Breast04 trial), including 2,479 patients (1,256 patients in ADCs treatment and 1,223 patients in conventional chemotherapy). HR for PFS was 0.48 [95% CI (0.38, 0.61), P = 0.001], and HR for OS was 0.60 [95% CI (0.46, 0.79), P = 0.027]. OR for incidence of all adverse events (AEs) was 1.05 [95% CI (0.86,1.29), P = 0.901], and OR for incidence of grade ≥ 3 AEs was 1.11 [95% CI (0.88, 1.42), P = 0.984]. The pooled results demonstrated that ADCs significantly improved OS and PFS, while showing no significant increase in overall AEs or grade ≥ 3 AEs compared to control. Conclusion This study suggests that ADCs significantly improve OS and PFS without significantly increasing grade ≥ 3 AEs compared to conventional chemotherapy in TNBC, providing support for clinical decision-making and guideline development. These findings may inform future head-to-head trials, optimization of ADC-based combination regimens, and biomarker-guided precision treatment. As clinical data on novel ADCs continue to accumulate, these conclusions may be further validated and extended.