Four-year follow-up of a phase III study comparing SB3 (trastuzumab biosimilar) and reference trastuzumab in HER2-positive early or locally advanced breast cancer in neoadjuvant setting.

578Background: SB3 was approved in the US and EU as a biosimilar of reference trastuzumab (TRZ). Here, we report 4-year cardiac safety and survival outcomes. Methods: After completing neoadjuvant-a...