GLP-1 Drugs Show Beneficial Effects Across Multiple Cancer Types, New Research Suggests

More than two dozen studies on GLP-1 drugs and cancer were presented at the American Society of Clinical Oncology meeting in Chicago in early June 2026. A study of 110,000 women showed up to 35% lower breast cancer risk with GLP-1 use, while a seven-year study with nearly 120,000 participants found lower prostate cancer rates. GLP-1 use was associated with 38% to 50% lower odds of metastatic disease for lung, breast, colorectal, and liver cancers compared to gliptins.

GLP-1 cancer protection evidence

• ▪GLP-1 medications carry a warning regarding a possible association with a type of thyroid cancer based on rodent studies.
• ▪Some trials testing GLP-1 drugs for cancer benefits are already being planned.
• ▪Dr. Marcin Chwistek of the Fox Chase Cancer Center in Philadelphia stated that the consistency of GLP-1 cancer data across tumor types warrants a prospective randomized trial.
• ▪A study of 110,000 women showed those who took GLP-1 medications were up to 35% less likely to develop breast cancer than those who did not.
• ▪GLP-1 drugs include semaglutide, the active ingredient in Wegovy, Ozempic and Rybelsus.
• ▪Patients taking GLP-1 drugs showed lower risks of developing cancer and disease progression compared with people not taking GLP-1s, according to studies presented at the American Society of Clinical Oncology meeting.
• ▪More than two dozen studies on GLP-1 drugs and cancer were presented at the American Society of Clinical Oncology meeting in Chicago in early June 2026.

Mechanisms of action

• ▪GLP-1 drugs were originally designed to treat diabetes and found to promote weight loss.
• ▪Dr. Colton Jones hypothesized that both weight loss and a direct anti-cancer effect and anti-inflammatory effect may be driving the associations observed in the prostate cancer study.
• ▪Researchers believe GLP-1 drugs may contribute to a protective effect in cancer patients by reducing inflammation, regulating insulin signaling, and possibly engaging directly with tumor biology.

Benefits across cancer types

• ▪A study of more than 12,000 patients showed GLP-1 use was associated with 38% to 50% lower odds of lung, breast, colorectal, and liver cancers advancing to metastatic disease compared to people who took gliptins.
• ▪GLP-1 users with type 2 diabetes and stage 3 kidney disease had substantially lower mortality and lower rates of lung, colorectal, and hepatocellular cancers than non-users.
• ▪Reduced cancer incidence, longer survival, and fewer metastases were seen with GLP-1 use in patients with endometrial, bladder, prostate cancers, small intestine neoplasms, and blood cancers.

Immunotherapy interaction

• ▪Cancer patients receiving immunotherapies such as Merck's Keytruda and Bristol Myers Squibb's Opdivo or Yervoy appeared to fare better when taking GLP-1 drugs.

Study limitations

• ▪Nearly all of the data presented at the American Society of Clinical Oncology meeting on GLP-1 drugs and cancer were from observational studies, raising the risk of confounding factors.
• ▪Trials in which GLP-1s are added to standard treatment in some cancer patients but not others are needed to establish clear anti-cancer benefits.
• ▪None of the GLP-1 cancer studies presented can prove the drugs improve cancer outcomes.

Weight loss independence

• ▪GLP-1 users in the prostate cancer study had a very small reduction in body weight at one year, according to Dr. Colton Jones of the University of Texas San Antonio Mays Cancer Center.
• ▪GLP-1 drugs have shown benefits for heart risks, sleep apnea, and alcohol and substance abuse.
• ▪The apparent cancer benefits of GLP-1 drugs were not clearly tied to the drugs' weight-loss effects.

Perspective of Researchers and oncologists

• ▪Dr. Marcin Chwistek of the Fox Chase Cancer Center in Philadelphia stated that the consistency of GLP-1 cancer data across tumor types warrants a prospective randomized trial.
• ▪Trials in which GLP-1s are added to standard treatment in some cancer patients but not others are needed to establish clear anti-cancer benefits.

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