Previous meta-analyses exploring the treatment of HR+/HER2- advanced breast cancer with sacituzumab govitecan (SG) [23, 24] have shown that compared to chemotherapy, SG significantly improves both progression-free survival (PFS) and overall survival (OS). In a network meta-analysis comparing the efficacy of different treatments for triple-negative breast cancer, SG ranked first in terms of PFS and OS among second-line or later treatments, outperforming HER2-ADCs, PARP inhibitors, and chemotherapy [25]. However, these two meta-analyses included only one Trop2-ADC drug. With the increasing number of Trop2-ADC options, further meta-analyses are needed to indirectly compare the efficacy of different drugs.
In a network meta-analysis exploring the efficacy of ADC drugs in patients with HER2-low metastatic breast cancer [26], no significant differences were observed in PFS and OS between SG and datopotamab deruxtecan (Dato-DXd) in HR+/HER2- or low-expressing advanced breast cancer patients. The pairwise indirect results in this study were similar; however, probabilistic ranking showed that Dato-DXd ranked higher than SG in terms of objective response rate (ORR) and PFS. In the OS analysis, SG ranked higher than Dato-DXd, which may be related to the maturity of OS data; it could also be due to the fact that the Dato-DXd studies included patients who had received 1-2 lines of prior chemotherapy, while most patients in the SG studies had received 2-3 lines of prior chemotherapy (the median absolute OS value for Dato-DXd (18.6 months) appears to be greater than that for SG (14.5 months)). Similar contradictory results in PFS and OS were observed in triple-negative breast cancer, possibly for the same reasons. Therefore, further research evidence is still needed.
