06/03/2026
A new Penn Medicine study of more than 110,000 women found that those who took GLP-1 medications were about 30% less likely to develop breast cancer than those who did not.
Presented yesterday at the 2026 ASCO Annual Meeting by Dr. Elizabeth McDonald, the research opens exciting new doors. While observational, the data suggests these widely used medications might help inhibit tumor growth by reducing systemic inflammation and targeting cancer pathways.
“Ultimately, we want to find better options to prevent breast cancer,” says Dr. McDonald. “We’d love to see the same gains in prevention that we’ve seen in survival rates.”
Up next: Our researchers are actively working to launch a multisite clinical trial to formally test GLP-1s for breast cancer prevention in high-risk individuals.