Dr Tolaney on the Future of HER2+ Breast Cancer Management

“In the HER2-positive breast cancer setting, we’ve seen so much change in the past few months, in the sense that we've seen change both for [patients with] metastatic HER2-positive [disease], but also for [patients with] early-stage, HER2-positive breast cancer. This has introduced a lot of options for our [patients with] metastatic [disease], and we’re all trying to figure out the optimal ways to think through these choices.”

Sara M. Tolaney, MD, MPH, chief of the Division of Breast Oncology and associate director of the Susan F. Smith Center for Women's Cancers and a senior physician at Dana-Farber Cancer Institute; as well as an associate professor of medicine at Harvard Medical School, emphasized the rapid and transformative evolution of therapeutic strategies within the HER2-positive breast cancer paradigm.

Tolaney noted that in recent months, the breast cancer field has seen significant shifts in treatment standards for patients with both metastatic and early-stage disease, driven by a wave of new clinical data. She highlighted findings from the phase 3 DESTINY-Breast09 trial (NCT04784715), which has established the combination of fam-trastuzumab deruxtecan-nxki (T-DXd; Enhertu) plus pertuzumab as a primary first-line treatment option for patients with HER2-positive metastatic breast cancer.

Furthermore, Tolaney pointed to the growing importance of maintenance strategies following induction therapy for this patient population. She cited data from the phase 3 HER2CLIMB-05 trial (NCT05132582), which evaluated the triplet regimen of tucatinib (Tukysa), trastuzumab (Herceptin), and pertuzumab (Perjeta) after taxane induction therapy in patients with metastatic HER2-positive breast cancer. In the context of advanced estrogen receptor–positive, HER2-positive disease, she referenced findings from the phase 3 PATINA trial (NCT02947685), which investigated the addition of the CDK4/6 inhibitor palbociclib (Ibrance) to endocrine therapy and HER2-targeted agents during maintenance therapy.

According to Tolaney, these diverse clinical developments in the breast cancer field have introduced a wealth of options for patients with metastatic disease. She observed that the current challenge for oncologists is to synthesize these data to determine the optimal sequencing and selection of therapies to improve patient outcomes.