Abstract

The first HER2-targeted medication, the monoclonal antibody trastuzumab, was approved about 25 years ago as a result of the long-awaited identification of HER2 as an effective and highly sensitive therapeutic target. This marked a significant advancement in the treatment of extremely aggressive HER2-positive breast cancer. Since then, development of newer platforms and more specific therapeutics has accelerated due to the outstanding clinical activity seen in several trials using monoclonal antibodies, tyrosine kinase inhibitors, and antibody-drug conjugates that target HER2. The current guidelines for treating HER2-positive breast cancer are covered in this review, along with the processes underlying resistance to HER2-targeted therapy and novel therapeutic agents, such as immune system-boosting techniques.