The Eli Lilly brand seems on the corporate’s workplace in San Diego, California, U.S., Nov. 21, 2025.
Mike Blake | Reuters
Eli Lilly on Thursday mentioned its next-generation weight problems drug delivered what seems to be the very best weight reduction but in a late-stage trial whereas decreasing knee arthritis ache, clearing the primary of a number of upcoming research on the weekly injection.
The best dose of the drug helped sufferers with weight problems and a sort of knee arthritis lose a mean of 23.7% of their physique weight at 68 weeks, when analyzing all members, together with those that discontinued remedy. When evaluating solely sufferers who stayed on the drug, the very best dose delivered 28.7% weight reduction on common.
The corporate mentioned some sufferers misplaced a lot weight that they determined to drop out of the trial.
“It is unbelievable,” mentioned Dr. Caroline Apovian, co-director of the Middle for Weight Administration and Wellness at Brigham and Girls’s Hospital. “Now, we now have a drug that rivals the load loss advantages of surgical procedure.”
Apovian mentioned Eli Lilly seems to be positioning the drug strategically for individuals with extreme weight problems, or a physique mass index above 35 or 40. She famous that the corporate mentioned 84% of sufferers within the trial had a BMI above that quantity within the trial.
Shares of Eli Lilly rose greater than 3% on Thursday.
It’s the first late-stage knowledge on retatrutide, which works in another way from current injections and seems to be simpler. Eli Lilly is betting massive on retatrutide as the subsequent pillar of its weight problems portfolio after its weight reduction injection Zepbound and its upcoming tablet. Nevertheless it’s nonetheless unclear when the drug might enter the market.
It is a vital a part of the drugmaker’s plan to take care of its market share majority over Novo Nordisk within the booming marketplace for weight reduction and diabetes medicine. Some analysts estimate the phase may very well be price about $100 billion by the 2030s.
Retatrutide additionally met the trial’s different most important purpose of decreasing ache from knee osteoarthritis – a standard situation that wears down the joint’s cartilage and results in ache and stiffness – by as much as 62.6% on common when analyzing all sufferers, based mostly on a extensively used survey. Greater than 1 in 8 sufferers who took the drug had been fully free from knee ache by the top of the trial, Eli Lilly mentioned.
One concern with present weight reduction medicine is that they’ll result in the lack of lean muscle mass. However Apovian mentioned the outcomes present that in adults with extreme weight problems, you possibly can enhance bodily operate with retatrutide.
The outcomes seem to surpass Wall Road’s expectations. In a notice forward of the findings, BMO Capital Markets analyst Evan Seigerman mentioned his base-case assumption was for the drug to indicate weight lack of round 20% to 23%, with at the very least a 50% discount in knee ache.
The corporate believes retatrutide “might develop into an necessary choice for sufferers with important weight reduction wants and sure problems, together with knee osteoarthritis,” Kenneth Custer, president of Lilly Cardiometabolic Well being, mentioned in a press release.
In a notice Thursday, JPMorgan analyst Chris Schott mentioned retatrutide’s tolerability knowledge, or how nicely sufferers deal with the remedy, is “considerably worse vs Zepbound, although not stunning, in our view.”
Roughly 18% of sufferers on the very best dose of the drug stopped remedy resulting from negative effects, in contrast with 4% of these within the placebo group. Eli Lilly mentioned these dropout charges had been “extremely correlated” to sufferers’ beginning physique mass index and included discontinuations resulting from “perceived extreme weight reduction.”
Amongst these with a BMI of 35 or larger who took highest dose, 12% stopped remedy. Schott mentioned that quantity is nearer to the dropout charges seen in trials on Eli Lilly’s weight reduction drug Zepbound and Novo Nordisk‘s weight problems injection Wegovy.
In a separate notice on Thursday, BMO’s Seigerman mentioned discontinuation charges “seem to focus on the pace and energy of weight reduction was extreme for some sufferers with decrease BMI.” However he mentioned, “all in outcomes are spectacular.”
Round 43% of sufferers on the very best dose skilled nausea, whereas roughly 33% and 20.9% had diarrhea and vomiting, respectively. Greater than 1 in 5 sufferers on the very best dose additionally skilled dysesthesia, which is an disagreeable nerve sensation. The corporate mentioned it was typically delicate for sufferers and barely led to them discontinuing remedy.
The research, referred to as TRIUMPH-4, did not solely give attention to weight reduction, which means that different trials particularly designed for that consequence might produce totally different or larger outcomes. Eli Lilly expects to report findings from seven extra section three trials on the drug by the top of 2026.
Dubbed the “triple G” drug, retatrutide works by mimicking three hunger-regulating hormones – GLP-1, GIP and glucagon – somewhat than only one or two like current therapies. That seems to have stronger results on an individual’s urge for food and satisfaction with meals than different therapies.
Tirzepatide, the energetic ingredient in Zepbound, mimics GLP-1 and GIP. Novo Nordisk’s semaglutide, the energetic ingredient in Wegovy, mimics solely GLP-1.
Greater doses of tirzepatide helped sufferers with weight problems lose roughly 20.9% of their physique weight on common in late-stage research, when analyzing all sufferers no matter discontinuations.
As Eli Lilly establishes an edge within the house, its chief rival, Novo Nordisk, is racing to catch up. In March, Novo Nordisk mentioned it agreed to pay as much as $2 billion for the rights to an early experimental drug from the Chinese language pharmaceutical firm United Laboratories Worldwide.
Novo Nordisk’s newly acquired drug is a transparent potential competitor to retatrutide as a result of it equally makes use of a three-pronged strategy to selling weight reduction and regulating blood sugar. However Novo Nordisk’s remedy is way earlier in improvement, which means it would take a number of years earlier than it reaches sufferers.
