Dana-Farber May Have Found a Breast Cancer Drug That Can Extend Survival

Patients with HER2-positive cancer lived an average of seven months longer than patients on other treatments.

Researchers from Dana-Farber Cancer Institute (DCFI) have identified a new breast cancer treatment that may allow patients to live almost 50 percent longer than those on other regimens.

In a trial of more than 600 patients with metastatic breast cancer, DCFI found that patients taking a combination chemotherapy and antibody drug—called T-DM1—lived an average of roughly seven months longer than patients on other treatments, a 44 percent improvement. In addition, patients on the T-DM1 plan had fewer serious side effects.

T-DM1 is a treatment specifically for the roughly 20 percent of breast cancer patients with HER2-positive breast cancer, an aggressive subset of the disease in which the HER2 gene malfunctions and causes breast cells to grow and divide uncontrollably. T-DM1 works by dispatching both an antibody, which helps block these growth signals, and chemotherapy, which disrupts the way the cells grow; the combination provides a more effective method of killing HER2-positive cells.

“Based on this study and others, T-DM1 should be considered the standard of care for patients whose cancer has progressed on a HER2-targeted treatment,” said Ian Krop, the study’s senior author, in a statement.

DCFI researchers will present the findings today at the San Antonio Breast Cancer Symposium.