Eli Lilly said its fast-growing diabetes drug Mounjaro demonstrated cardiovascular protection comparable to—and slightly better than—its older medicine Trulicity in a large, head-to-head study, potentially widening the drug’s clinical and commercial lead in the GLP-1 class. The late-stage SURPASS-CVOT trial enrolled more than 13,000 adults with type 2 diabetes and established atherosclerotic heart disease and followed them for almost five years. Mounjaro reduced the incidence of major adverse cardiovascular events—including cardiovascular death, heart attack and stroke—by 8% relative to Trulicity, meeting the study’s primary objective of non-inferiority. Although the superiority threshold was not reached for the composite heart endpoint, Mounjaro was linked to a 16% lower rate of death from any cause. Secondary analyses showed greater reductions in blood-sugar levels, body weight and markers of kidney function, while overall safety was similar, with mainly mild-to-moderate gastrointestinal side effects. Lilly said it will submit the data to the U.S. Food and Drug Administration later this year, aiming for a 2026 label expansion that could extend insurance coverage for Mounjaro’s cardiovascular use. The drug generated $11.5 billion in sales last year, overtaking Trulicity’s $5.2 billion. Investors reacted coolly, sending Lilly shares down as much as 4.9% intraday, as some analysts had expected clearer statistical superiority. Even so, the findings reinforce Mounjaro’s position against rival GLP-1 therapies and deepen Lilly’s pipeline of potential cardiometabolic indications.