Eli Lilly’s weight-loss drug reduces risk of developing diabetes in long-term trial

In a recent long-term research study published Tuesday, Eli Lilly reported that its popular weight-management drug significantly reduced the incidence of type 2 diabetes by 94 percent among overweight or obese adults who had prediabetic symptoms, compared to a control group that received a placebo.

The late-stage study explored the effects of tirzepatide, the active compound in both Eli Lilly’s Zepbound weight-loss shot and the diabetes treatment Mounjaro. Over about three years, participants who received the highest weekly dose of tirzepatide experienced an average reduction in body weight of 22.9 percent, while those who took a placebo saw only a 2.1 percent reduction after 176 weeks.

Following the release of these results, Eli Lilly shares rose nearly 3% on Tuesday.

The study highlights the potential of tirzepatide to significantly delay the onset of type 2 diabetes in people whose blood sugar levels are higher than normal but not high enough to warrant a diagnosis of diabetes.

With over a third of Americans currently classified as prediabetic, health experts emphasize the reversibility of this condition through lifestyle changes such as improved diet and regular physical activity. Individuals who are overweight or obese are particularly susceptible to prediabetes.

The trial also demonstrated the potential long-term health benefits of GLP-1 drugs, which are designed to mimic gut hormones that help regulate appetite and blood sugar levels. This class of drugs, including Zepbound and Mounjaro, as well as competing brands, has received considerable attention in the past two years, spurring a wave of clinical research into their broader health benefits.

“These results reinforce Lilly’s substantial commitment to demonstrating the health benefits of weight management,” commented Eli Lilly CEO David Ricks. He noted that tirzepatide is also being studied in separate studies for its effects on heart failure, sleep apnea and fatty liver disease.

Eli Lilly conducted this Phase 3 study in more than 1,000 adults for 176 weeks, followed by a 17-week observation period after cessation of treatment. It is the longest study completed on tirzepatide to date.

The company plans to submit these results for peer review and present them at a medical conference in November. Additionally, Eli Lilly plans to publish data from a larger patient group over a 72-week period from the same SUMOUNT-1 study in 2022.

After stopping the drug during the study, participants began to regain weight and experienced an increase in diabetes progression, while maintaining an 88% reduced risk of developing the disease compared to the placebo group.

“Maintaining a healthy weight and keeping diabetes at bay for up to three years demonstrates the drug’s effectiveness,” Ricks said. “However, after stopping, there is a tendency for weight gain and a gradual return to diabetes.”

Ricks also noted that patients’ responses after treatment did not return exactly to their pre-treatment state.

The safety profile of tirzepatide throughout the trial was consistent with previous studies; the most common side effects were mild to moderate gastrointestinal problems.

Zepbound works by mimicking two gut hormones, GLP-1 and GIP, which play a key role in reducing food intake and improving the metabolic breakdown of sugars and fats.