Eli Lilly said on August 28 that the FDA has approved Mounjaro to help reduce cardiovascular risk in people with type 2 diabetes who are at high risk of cardiovascular events. Heart disease is the leading cause of death in that group, Lilly Cardiometabolic Health president Kenneth Custer said in a press statement announcing the decision.

Mounjaro is tirzepatide, a dual GIP and GLP-1 receptor agonist. Randy Gould, DO, a cardiologist with Manhattan Cardiology who was not involved in the trial, told Healthline it lowers blood sugar by increasing metabolic processing and reducing fat accumulation in the liver, and that it signals the pancreas to release insulin after eating while slowing digestion.

The head-to-head design

The approval rests on SURPASS-CVOT, which Healthline describes as the first cardiovascular outcomes trial to compare two GLP-1 medications head-to-head rather than against a placebo. That is the genuinely interesting part, and it is the kind of comparison the field has mostly avoided because placebo arms are easier to win.

It was also the largest and longest tirzepatide study so far, with more than 13,000 participants across 30 countries and a median follow-up of four years. The comparator was Trulicity (dulaglutide), a GLP-1 drug with an already established cardiovascular benefit.

Key results

Major cardiovascular events occurred in 12.2% of participants taking Mounjaro, compared with 13.1% of those taking Trulicity. That worked out to an 8% lower relative risk, and the finding was reported as noninferiority rather than superiority.

Mir Ali, MD, of MemorialCare Surgical Weight Loss Center, who was not involved in the trial, called it encouraging news suggesting Mounjaro may offer benefits beyond blood sugar and weight. He also said more research is needed to know whether any of that is independent of weight loss and improved diabetes control.

Where the evidence stops

Rigved Tadwalkar, MD, of Pacific Heart Institute, told Healthline the studied population was very high risk: people with type 2 diabetes and established cardiovascular disease. He cautioned against extending the same conclusions to everyone taking tirzepatide.

Bottom line

The label change formally recognizes cardiovascular event reduction as part of the drug's clinical benefit, and Gould noted it may make insurance coverage easier to obtain. What the trial did not answer is how much of that effect belongs to the drug itself rather than to the weight and glucose changes it produces.