Dr. Favret on the Evolution of Treatment in HER2+ Breast Cancer

Anne Favret, MD, medical oncologist and co-director of Breast Research at Virginia Cancer Specialists, discusses the evolution of treatment in HER2-positive breast cancer.

Historically, the first-line treatment of patients with early-stage HER2-positive breast cancer has been a combination of docetaxel, trastuzumab (Herceptin), and pertuzumab (Perjeta; THP), explains Favret. Following THP, patients receive ado-trastuzumab emtansine (T-DM1; Kadcyla) in the second-line setting, and chemotherapy plus HER2-targeted therapy in the third-line setting.

However, data from the phase 3 APT trial showed a 93% disease-free survival rate at 7 years with adjuvant paclitaxel in combination with trastuzumab in women with small, node-negative HER2-positive breast cancer. These data suggest that patients with node-negative tumors that are 3cm or less in size are being overtreated with THP plus carboplatin (TCHP), says Favret.

In the advanced setting, the combination of tucatinib (Tukysa), trastuzumab, and capecitabine (Xeloda) recently received FDA approval for the treatment of patients with unresectable locally advanced or metastatic HER2-positive breast cancer, following at least 1 prior anti—HER2-based regimen in the metastatic setting. The regimen was also approved for patients with brain metastases.

Another agent, fam-trastuzumab deruxtecan-nxki (DS-8201; Enhertu) was approved in December 2019 for the treatment of patients with unresectable or metastatic HER2-positive disease who received at least 2 prior anti—HER2-based therapies in the metastatic setting.