Current Landscape of Anti-HER2 Targeted Therapy in Breast Cancer: Challenges and Future Perspectives

HER2-positive breast cancer is an aggressive subtype effectively targeted by monoclonal antibodies such as trastuzumab and pertuzumab, along with ADCs, TKIs, and chemotherapy. Despite clinical success, challenges including therapeutic resistance, toxicity, immune modulation, and high treatment costs persist. This review highlights emerging therapeutic strategies to address these issues, such as advanced monoclonal antibodies, combination regimens, downstream pathway inhibitors, and cost-effective biosimilars. Emphasis is placed on overcoming resistance mechanisms and improving treatment accessibility, aiming to enhance outcomes for patients with HER2-positive metastatic breast cancer.