Lilly weight loss drug prevents diabetes, company says

Drug giant Eli Lilly says its weight-loss drug tirzepatide helps people with obesity avoid getting diabetes, even months after stopping the medication.

Excess weight increases the risk for diabetes and losing weight reduces that risk, but substantial weight loss has been so challenging that few people manage it for long. A new class of medications, called GLP-1s, offer the first effective treatment for many people. They include tirzepatide, which Lilly sells as Zepbound for weight loss.

The three-year study, known as SURMOUNT-1, showed people with pre-diabetes who took the highest dose, a weekly 15 mg shot, lost nearly 23% of their body weight on average. Their risk of developing diabetes was 94% lower than people with pre-diabetes who received a placebo and lost about 2% of their body weight on average, according to a company press release.

At one level, it's not surprising that a drug that causes weight loss and treats diabetes would also prevent the disease, said Dr. William Dietz, who directs the Sumner M. Redstone Global Center for Prevention and Wellness at the Milken Institute School of Public Health at The George Washington University. But, still, it's good to confirm.

"The results we're seeing are the consequence of how quickly and substantially the weight is lost," he said.

Dr. Eric Topol, a cardiologist and the director of the Scripps Research Translational Institute, described the finding as "welcome news," but cautioned that the data the company released was too sketchy to really understand its significance.

A 94% reduction sounds great, he said, but the company didn't reveal the actual figures, so it's unclear if the drug helped 200 people avoid getting diabetes or just two. "They didn't give one bit of data of how many people progressed (to diabetes) over that study period," Topol said. "It's like they're hiding something."

Lilly also sells tirzepatide under the brand name Mounjaro, to treat people with diabetes, though they typically lose less weight than people without the disease. The list price of both Mounjaro and Zepbound runs about $1,000 , though coupons and discounts can reduce the cost

Other GLP-1 drugs, which include semaglutide, sold by Novo Nordisk as Ozempic to treat diabetes and Wegovy for weight loss, can cost more.

Many insurance carriers do not cover the cost of weight-loss medications. Medicare does not cover medications for the sole purpose of weight loss , though in some states, Medicaid will cover the drugs .

Topol praised GLP-1s for their effectiveness, both for weight loss and for their apparent ability to reduce inflammation. "It's a weight loss drug, but it's probably more than that," he said, citing heart disease and diabetes, for which the drugs are already approved, and potentially neurodegenerative diseases like Alzheimer's and Parkinson's, which are being studied .

But he criticized the "price-gouging mode" of both companies. "It's a shame that these are not inexpensive drugs," Topol said, noting that people who need them most are often low-income, with multiple health problems and weak insurance coverage.

The drugs also remain in short supply with both companies unable to keep up with demand.

Other research has shown that the people most likely to get GLP-1s are those with private health insurance .

Patients who need these medications the most must be prioritized, Dietz said. And it is important to develop with new approaches to weight maintenance. Although the makers of GLP-1 drugs say that people have to be on them for life to maintain weight loss, Dietz said that's not sustainable at their current cost and it may be unnecessary, if there are other treatments and lifestyle changes available.

In the SURMOUNT-1 trial, Lilly gave nearly 2,000 volunteers with pre-diabetes and obesity or overweight the drug at one of three different doses and 640 people a placebo and lifestyle counseling and followed them for 193 weeks, the last 17 of them after they'd discontinued the drug.

The company published interim results in 2022 in the New England Journal of Medicine , after 72 weeks of treatment, which included 20 weeks in which participants were slowly ramped up to their final dose. At that point, 85% of those on the drug had lost more than 5% of their body weight and 15% of those on the two higher doses lost 20% or more.

After discontinuing the drug, while still being followed, participants began regaining weight and some increased in their progression toward type 2 diabetes, according to the company. However, they still saw an overall 88% reduction in the risk of developing diabetes compared to participants who took a placebo.

People who take GLP-1 drugs experience a range of side effects. Those typically affect the gastrointestinal system and can include diarrhea, nausea, constipation and vomiting.

Both semaglutide and tirzepatide work by regulating appetite and limiting the calories people eat ‒ "quieting the food noise," as many patients put it. Tirzepatide includes a second method of action that may make it more effective at weight loss than semaglutide.

Karen Weintraub can be reached at kweintraub@usatoday.com.

This article originally appeared on USA TODAY: Lilly weight loss drug prevents diabetes, company says