A systematic review and meta-analysis showed that GLP-1 receptor agonists weren’t associated with increased risk for incident breast cancer.
Giovana Fagundes Piccoli, MD, of the Hospital de Clínicas de Porto Alegre in Brazil presented the findings at the Endocrine Society’s virtual ENDO 2021 meeting.
Out of 48 267 patients treated with a GLP-1 receptor agonist there were 130 cases of incident breast cancer among versus 107 cases out of 40 755 controls. Control participants received either placebo or active treatment with a non-GLP-1 receptor agonist.
There was also no difference in risk of benign breast neoplasms for patients on GLP-1 receptor agonists versus other drug types (RR 0.99).
No difference was seen among individual GLP-1 receptor agonists, including each of the four major drugs in the class — liraglutide, dulaglutide, semaglutide, and albiglutide — with exendin-4 mimetic agents including exenatide and lixisenatide.
No difference in incident breast cancer risk was seen when comparing trials with an open-label design versus double-blinded trials.
Dr Piccoli explained that her team wanted to investigate the issue further following the 2015 SCALE Obesity and Prediabetes trial, which found more breast neoplasms in patients receiving liraglutide than with placebo (4.36 vs 1.80 per 1000 person years). In that study, most of those neoplasms developed in the first year of treatment with GLP-1 receptor agonist, and were more common in participants with greater weight loss on the agent.
“I think that the results of our meta-analysis adds more security and safety information about this treatment,” said Dr Piccoli during a press conference. “Patients, doctors, and other health professionals can be more secure of the safety of these drugs.”
For this analysis, her team searched a variety of medical journal databases for randomised trials assessing GLP-1 receptor agonists in adults with overweight, obesity, prediabetes, or type 2 diabetes that also reported breast cancer or benign breast neoplasm incidence.
Participant ages ranged from 45 to 70 years old and follow-up lasted between 24 weeks to 7.5 years.
Piccoli emphasised that these findings only apply to patients treated with a GLP-1 receptor agonist for diabetes control or weight loss in the absence of pre-existing breast cancer. She added that patients with a history of breast or any other cancer were usually excluded from the trials in this meta-analysis.
“We can say in a general population with type 2 diabetes and obesity, [GLP-1 receptor agonists] are safe,” Piccoli said. But the class’s safety in patients with a history of breast cancer is less certain, she added.
Source: MedPage Today
Presentation information: Piccoli G, et al “Do GLP-1 receptor agonists increase the risk of breast cancer? A systematic review and meta- analysis” ENDO 2021.
