Popular weight loss, diabetes drugs linked to improved breast cancer survival: JAMA

New research published today in JAMA Network Open offers illuminating evidence suggesting there is a positive association between GLP-1 agonists-drugs commonly used to treat obesity and diabetes-and better outcomes among breast cancer patients.

“This study suggests that GLP-1 drugs may offer protective benefits potentially improving survival and recurrence risk in some female patients with breast cancer – whether this is related to weight control, improve cardiovascular health or other mechanisms remains to be studied,” said study senior author Bernard F. Fuemmeler, Ph.D., MPH, associate director for population sciences and the Gordon D. Ginder, M.D., Chair in Cancer Research at VCU Massey Comprehensive Cancer Center.

The research findingsThrough a retrospective cohort study examining the electronic health records of more than 840,000 breast cancer patients who were diagnosed between 2006 and 2023, the results suggest there is a potential link between GLP-1 RAs and improved outcomes among breast cancer patients who are also obese or have type 2 diabetes.

GLP-1 RA use was associated with an overall lower risk of death from any cause over a 10-year follow-up period among breast cancer patients. Additionally, breast cancer survivors who used GLP1-RAs for diabetes or obesity had a significantly lower risk of their cancer returning over 10 years following their initial treatment.

“Our findings align with emerging preclinical research and contribute to a growing body of literature related to GLP-1 RA use in oncology settings,” said study lead author Kristina L. Tatum, PsyD, MS, of the VCU School of Public Health.

What’s next?Further studies are needed to understand the biological mechanisms, if any, between GLP-1 RAs and breast cancer outcomes. The research team intends to further evaluate these correlations through randomized clinical trials.

“Our study underscores the potential of GLP-1 RAs as an adjunct strategy for improving cancer-related outcomes among patients with breast cancer, although clinical trials are needed to inform effective therapeutic approaches and clinical decision making,” Fuemmeler said.

About breast cancer

• The most common cancer among women in the US, except for skin cancer, accounting for nearly one-third of all female cancer cases.
• The average risk of a woman in the US developing breast cancer sometime in her life is about 13%.

Breast cancer patients who are also obese or have type 2 diabetes experience more aggressive cancer growth and worse outcomes. Prior studies have shown that weight loss treatment and surgery following a breast cancer diagnosis are associated with improved heart health and increased survival.

What are GLP-1 drugs?

• Glucagon-like peptide-1 receptor agonists (GLP-1 RAs).
• Approved to treat type 2 diabetes in 2005 and weight management in 2021.
• Impacts on breast cancer survival and recurrence are still unclear.

Since 2020, the use of these drugs has increased dramatically, where approximately 12% of Americans have used GLP-1s for weight loss, according to a RAND report.

Reference:

Tatum KL, Dahman B, Stevenson A, et al. Survival and Recurrence With GLP-1 Receptor Agonists in Breast Cancer. JAMA Netw Open. 2026;9(5):e2612133. doi:10.1001/jamanetworkopen.2026.12133