• Next-generation sequencing (NGS) is crucial for personalizing treatment decisions in hormone receptor (HR)-positive, HER2-negative metastatic breast cancer, identifying actionable mutations like PIK3CA, AKT, and P10.
• The phase 3 INAVO120 trial demonstrated that inavolisib, a PI3K kinase inhibitor, combined with palbociclib and fulvestrant, significantly improved progression-free survival in patients with PIK3CA-mutated HR-positive, HER2-negative breast cancer.
• The CAPItello-291 trial showed that capivasertib plus fulvestrant led to longer progression-free survival, especially in patients with PI3K, AKT, or P10 alterations, with manageable adverse events.
• Antibody-drug conjugates like fam-trastuzumab deruxtecan-nxki and sacituzumab govitecan-hziy are promising for HER2-low breast cancer, necessitating further research to optimize their sequencing for maximum patient benefit.