People taking Eli Lilly’s next-generation GLP-1 obesity drug retatrutide shed more pounds than any other weight-loss drug during a late-stage trial, the company said Thursday.
Patients using the highest dose of the once-weekly shot, over the course of 68 weeks, lost an average of up to 71.2 pounds at the end of the Phase 3 clinical trial.
During the trial, participants on the 12 milligram dose shed an average of 28.7 percent of their body weight – which is more than the average achieved with Zepbound or competitor Novo Nordisk’s Wegovy – and more than 23 percent lost at least 35 percent of their initial weight. Zepbound, Wegovy and Ozempic are some of the most popular weight-loss drugs currently on the market.
More than 12 percent of those patients in the retatrutide drug lost so much weight and experienced other “adverse events” that they stopped taking the drug, Eli Lilly said. Over 20 percent of people on the highest dose of the Eli Lilly drug also had a condition that makes touching the skin painful. Still, the majority of side effects were consistent with those felt when taking weight loss drugs currently on the market.
But weight loss wasn’t the only major effect.
Retratrutide also reduced arthritic knee pain by an average of 75.8 percent and significantly improved physical ability, according to Eli Lilly.
More than one in eight of the 445 participants with obesity and knee arthritis were “completely free from knee pain at the end of the trial,” including a slightly higher number of patients who took a lower dose.
Knee arthritis is a common condition, affecting about 20 percent of Americans older than the age of 45, according to Georgia’s Northside Hospital. It is more common in people living with obesity.
“With seven additional Phase 3 readouts expected in 2026, we believe retatrutide could become an important option for patients with significant weight loss needs and certain complications, including knee osteoarthritis,” said Kenneth Custer, the executive vice president of Eli Lilly and Company and president of Lilly Cardiometabolic Health.
Eli Lilly noted that the drug reduced known biomarkers of cardiovascular risk, as well, and lowered systolic blood pressure by 14 millimeters of mercury, the measurement of the force in your arteries as your heart beats.
Additional results from the trial, which include a lower dose of four milligrams in addition to the nine and 12 milligrams and the placebo tested in this trial are expected next year.
Eli Lilly is simultaneously developing a new pill for weight loss and an amylin analog injection that would help people lose weight without muscle mass loss, a common side effect of current drugs.
