Four new studies reviewing data from tens of thousands of patients suggest that blockbuster GLP-1 drugs from Novo Nordisk A/S and Eli Lilly & Co. are associated with up to a 50% reduction in cancer progression.
"In multiple cancers, people who are on these medicines seem to have a lower risk of their cancer recurring, and that is a really striking finding," said Dr. Jennifer Ligibel, a breast oncologist at the Dana-Farber Cancer Institute, who was not involved in the research.
The largest of the four retrospective studies, conducted by the Cleveland Clinic Cancer Institute, showed that the risk of lung cancer advancing was approximately halved, with a progression rate of about 10% in GLP-1 users compared to 22% in a control group. For breast cancer patients, the progression rate dropped from 20% to 10%. Another study from the University of Texas MD Anderson Cancer Center found the five-year survival rate for breast cancer patients using GLP-1s was over 95%, versus 89.5% for non-users.
The findings, set to be presented at the American Society of Clinical Oncology (ASCO) annual meeting, point to another major potential benefit for a class of drugs already approved for weight loss, diabetes, and reducing heart attack risk. However, researchers stress the data is observational and does not yet prove a direct cause-and-effect relationship, which would require confirmation from randomized controlled trials.
The research from the Cleveland Clinic tracked over 10,000 patients with early-stage cancer. It found that those who began using GLP-1 medications after their diagnosis had a significantly lower risk of their cancer spreading compared to patients on other diabetes medications. Statistically significant reductions in progression were also observed in colorectal and liver cancers.
"Given that millions of Americans are using GLP-1s, it is imperative that we understand their potential anti-tumor effects," Dr. Mark Orland, a resident physician at the Cleveland Clinic and presenter of the study, said in a statement.
A separate analysis by the University of Pennsylvania, which included nearly 95,000 women undergoing breast imaging, discovered that those who had previously used GLP-1 drugs had about a 25% lower risk of being diagnosed with breast cancer.
Scientists are exploring two primary hypotheses for the potential anti-cancer effects. The first is an indirect benefit: GLP-1 drugs drive significant weight loss and improve overall metabolic health, both of which are independently linked to lower cancer risk.
A second theory suggests a more direct role. Receptors for the GLP-1 hormone, which the drugs mimic, have been found on some tumor cells. This raises the possibility that the medications could directly interfere with the biological processes of the cancer itself. Neither Novo Nordisk nor Eli Lilly are currently conducting specific clinical trials for a cancer indication.
The consistent signal across multiple large databases has captured the attention of the oncology community, even with the limitations of retrospective data. The studies relied on insurance claims and medical records, which can have inherent biases; patients prescribed GLP-1s may have better access to healthcare, a factor that could independently improve outcomes.
The results add a significant new dimension to the value proposition for GLP-1 drugs, which have already reshaped the pharmaceutical market. Confirmation of an anti-cancer benefit in future trials would further solidify the standing of Novo Nordisk and Eli Lilly and could reshape medical guidelines and reimbursement policies for the multi-billion dollar drug class. Investors will be watching for any announcements of randomized controlled trials to validate these early findings.
This article is for informational purposes only and does not constitute investment advice.
