Dr. Bardia on Potential Concerns With Biosimilars in Breast Cancer

Aditya Bardia, MD, MPH, director of Precision Medicine at the Center for Breast Cancer, Massachusetts General Hospital Cancer Center, Harvard Medical School, discusses potential concerns regarding the use of biosimilars in the breast cancer space.

There is a lot of interest in developing biosimilars in breast cancer. One of the biosimilars that are being used in patients who are receiving cancer care is filgrastim-sndz (Zarxio), although MYL-1401O (Ogivri; trastuzumab-dkst), the first trastuzumab (Herceptin) biosimilar, was approved by the FDA in December 2017. The main advantage of a biosimilar is its potential to reduce cost, explains Bardia, which is important because financial toxicity is a reality that many patients face in not only breast oncology, but the field of oncology as a whole.

Biosimilars must meet strict criteria to reach regulatory approval, they are not as thoroughly vetted as the originator biologic, explains Bardia. Although these studies have to demonstrate equivalence to that of a biologic, the path toward regulatory approval is not as rigorous as that of a new compound. Even if a biosimilar demonstrates similarity, it may not be identical, he cautions.