Weight loss from Lilly’s Zepbound drug reversed after stopping treatment, according to study

Weight loss from Eli Lilly’s Zepbound drug can reportedly be reversed if users stop treatment, according to a new study.

In a study published in the journal JAMA, patients on the drug who struggled with non-diabetic obesity were reported to have 14 per cent weight regain nearly a year after switching to a placebo after an eight-month treatment of Zepbound. Those who weren’t given the placebo reportedly experienced an additional 5.5 per cent weight reduction throughout the 52 weeks in which data was collected.

Before the study rocked Wall Street, analysts argued that Zepbound could potentially be the best-selling drug of all time.

After the news broke, Eli Lilly shares fell to less than 2 per cent in morning trading on 11 December, indicating a lack of faith amongst shareholders in the company.

Lilly’s tirzepatide has been sold to consumers and patients under the brand name Zepbound for weight loss and shares an active ingredient with their type 2 diabetes drug Mounjaro.

Eli Lilly published some of the trial results in July, with results showing that users on GLP-1 drugs would likely have to continue their therapy long-term. At the time, Goldman Sachs analysts said, “We await additional longer-term data to assess the effects of tirzepatide and other incretin-based therapies after multiple years of continuous therapy.”

With the entire treatment period consisting of 88 weeks, those who continued to use tirzepatide showed 25.3 per cent weight loss. Meanwhile, patients who switched to a placebo after 56 weeks had an overall weight reduction of 9.9 per cent throughout the entire study period.

Those involved in the study reportedly told patients to eat around 500 calories and exercise at least 150 minutes a week. Only about 17 per cent of patients who continued with Zepbound maintained at least 80 per cent of their original weight.

In an interview with CNN, lead study author Dr. Louis Aronne - an obesity medicine specialist and professor of metabolic research at Weill Cornell Medicine in New York City - explained the findings to the outlet. She said, “If you look at the magnitude of the weight gain, they gain back about half the weight they had originally lost over a one-year period of time.”

Like its weight loss drug counterparts Ozempic and Wegovy from Novo Nordisk, tirzepatide is one of many obesity and weight loss treatments that target the GLP-1 hormone that tells your mind that your body is full after eating.

In March, officials from Novo Nordisk revealed that patients choosing to discontinue treating obesity or type 2 diabetes with these weight loss drugs reportedly are at risk of regaining their initial body weight in five years. In a study funded by Novo Nordisk released last April, patients reportedly regained two-thirds of the weight they lost after just one year of stopping the drug treatment.