A new experimental obesity drug from Eli Lilly is showing what experts are calling unprecedented weight loss results.
Retatrutide, the company’s newest weight loss medication, helped people lose about 85 pounds, according to the results of a late-stage clinical trial. The drug is not yet FDA approved.
Dr. Susan Spratt, a Duke Health diabetes and metabolism specialist and professor of medicine at Duke University School of Medicine, compared the results to gastric bypass surgery.
“The amount of weight loss in this study is really a game changer,” Spratt said. “It is reaching levels that you typically see only with gastric bypass surgery.”
The study included approximately 2,300 adults living with obesity. A BMI of 30 or above is considered obese. According to trial data, 65% of participants taking the highest 12-milligram dose of retatrutide dropped below a body mass index of 30.
Spratt said retatrutide targets three hormones involved in appetite and metabolism, unlike other medications like Wegovy and Zepbound.
“It’s a GLP-1 agonist, a GIP agonist, and a glucagon agonist,” Spratt explained. “Something about that combination is causing really dramatic weight loss for people who have obesity.”
Gastric bypass surgery rates have already dropped since weight loss drugs became more popular in recent years, according to Spratt. However, the physician warned the medications are not a “miracle cure.”
“I don’t want people to see my huge excitement about medication as a rejection of food as medicine. It really is both,” Spratt stated. “We need healthy food, healthy exercise, and medications that can help us stay on the right track. That’s how I see this working in this space.”
Spratt also cautioned that rapid weight loss can lead to muscle and bone loss alongside fat if patients are not maintaining proper nutrition and exercise habits.
The study results come as conversations surrounding weight-loss drug pricing and insurance coverage continue. Spratt shared the new medication brings additional concerns over affordability and accessibility.
“I’m concerned about access. I’m sure the drug is going to be priced expensively. It works really well. There’s no reason for a company to cut the price,” Spratt said. “I am very concerned about the cost of these life-saving medications. They are life-altering, and it shouldn’t be that only people who have good insurance or extra income should be able to pay for them.”
Spratt says she hopes to see retatrutide be approved for use in patients with prediabetes who often face more difficulty in affording weight loss medications.
“I would love for this drug to be approved for prediabetes so that patients would never have to face diabetes complications, which can be very costly not only in terms of financial costs, but also just costly to quality of life,” she said.
The study did not directly address what happens after patients stop taking retatrutide. Spratt said she expects it would likely be similar to other weight-loss medications, potentially involving some degree of weight regain over time.
According to the company, results of all registered clinical trials are avialable to the public on clinicaltrials.gov either 30 days after the approval of the medicine (Phase 1) or within one year after a trial has completed (Phases 2-4).
The phase 3 clinical trial results come after patients lost up to 58 pounds in phase 2 clinical trial in 2023.