Dr. Tripathy on the Evolving Treatment Landscape of HER2+ Breast Cancer

Debu Tripathy, MD, professor of medicine and chair of the Department of Breast Medical Oncology at The University of Texas MD Anderson Cancer Center, discusses the evolving treatment landscape of HER2-positive breast cancer.

Certain cancers are driven largely by genetic aberrations that result in unique protein characteristics, Tripathy says. Although the tumor may progress through different stages of resistance, these characteristics, such as the expression of the HER2 receptor, play a critical role in driving the cancer.

In HER2-positive breast cancer, all available treatments target HER2 in some way, explains Tripathy. However, novel therapies such as fam-trastuzumab deruxtecan-nxki (Enhertu) and ado-trastuzumab emtansine (T-DM1; Kadcyla) target HER2 differently than conventional therapies.

Trastuzumab deruxtecan is an antibody-drug conjugate that delivers a toxic chemotherapy payload directly to the tumor cell. The agent is not specific to HER2. T-DM1 selectively and specifically inhibits HER2 rather than also inhibiting EGFR like other TKIs, Tripathy explains.

Although both agents have elicited significant responses in the relapsed/refractory setting of HER2-positive breast cancer, other novel therapies are garnering excitement in the pipeline, concludes Tripathy.