New drug tirzepatide delivers significant and long-lasting weight loss

For adults struggling with weight, a weekly injection of tirzepatide offers real hope. Recent findings presented at the European Congress on Obesity (ECO) in Malaga, Spain, reveal that the drug leads to significant and lasting weight loss over three years. This could change how healthcare providers manage obesity in adults without diabetes, paving the way for tailored treatments.

The research, headed by Dr. Luca Busetto from the University of Padova in Italy, tracked adults who had overweight or obesity but did not have diabetes. The study extended an earlier clinical trial known as SURMOUNT-1. Researchers looked at 700 adults, around 64% women, with an average age of 48. Each participant received weekly doses of tirzepatide—either 5 mg, 10 mg, or 15 mg—for three years.

At the end of this period, the results were impressive. On average, participants lost between 10% and 30% of their initial weight. Even more encouragingly, most people maintained the weight loss for the entire three-year study.

“Our long-term analysis of tirzepatide establishes that clinically relevant weight loss can be sustained for up to three years,” Dr. Busetto noted. He added, “Regardless of age, BMI, and duration of obesity, meaningful weight loss was possible.”

Not everyone responded equally to tirzepatide. The researchers identified three distinct groups, each showing different patterns of weight loss and weight stability.

The first group lost weight gradually, achieving about 10% weight reduction and hitting their lowest weight quickly. A second group experienced more rapid weight loss initially, about 20%, but stabilized later. The third and most successful group rapidly shed approximately 30% of their weight, hitting a plateau only after nearly a year.

Women and participants without obesity-linked health problems most commonly fell into this third group, achieving the greatest weight loss overall. Dr. Busetto explained, “Adults in Group 1 were on average almost 10% lighter than their initial body weight after three years. Participants in Group 3, however, lost another 20%, totaling about 31% weight loss.”

Tirzepatide mimics two key hormones in your body, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). Both hormones play essential roles after eating, signaling your pancreas to release insulin. Tirzepatide also slows the stomach's digestion rate and communicates with the brain to create a sense of fullness, reducing hunger significantly.

The medication, developed by Eli Lilly and Company, was approved by the U.S. FDA under the brand Zepbound in November 2023, and by European regulators as Mounjaro in June 2024. It targets obesity or overweight in adults who have at least one related health issue, like high blood pressure or high cholesterol.

Despite the effectiveness of tirzepatide, nearly everyone eventually reached a point where they stopped losing additional weight—a common occurrence known as a weight plateau.

Dr. Busetto explained why this happens: "Everyone hits a weight loss plateau at some point, no matter which weight loss intervention they use. GLP-1 and GIP are just two of eight hormones that control hunger and weight. Eventually, other hormones activate protective mechanisms to prevent further weight loss."

Among the study groups, the timing of this plateau differed significantly. Groups losing weight rapidly took longer to plateau, typically between 36 and 48 weeks into treatment, compared to about 24 weeks for those losing weight more gradually.

In another important finding presented at the ECO, Professor Louis Aronne from Weill Cornell Medicine highlighted minimal weight regain with tirzepatide treatment. Of the nearly 700 adults studied over three years, most only regained about 4% of their lowest achieved weight.

Specifically, 70% of participants regained 5% or less from their lowest weight. Less than 10% regained more than 10%. Professor Aronne said these results were encouraging because “most participants receiving tirzepatide had a relatively stable weight journey over three years and managed to avoid substantial weight regain.”

Clinically significant weight loss is typically defined as losing at least 5% of initial body weight. Dr. Busetto highlighted how even modest weight loss can dramatically improve overall health. For instance, losing just 5% of your weight significantly reduces your risk of developing diabetes, while a 15% loss leads to substantial improvements in blood pressure and cholesterol levels.

The study also confirmed tirzepatide's safety profile, with no new health concerns identified over three years. The most common side effects reported were mild gastrointestinal symptoms like nausea, diarrhea, and constipation, similar to those found in earlier trials.

These long-term results could pave the way for more personalized weight management strategies. Identifying early who might benefit most from treatments like tirzepatide could optimize outcomes. According to Dr. Busetto, “The findings could provide deeper insights into the efficacy of tirzepatide across different demographics and medical histories, potentially allowing for more individualized treatment plans.”

Healthcare providers might soon be able to predict a patient's likely weight loss trajectory based on their initial health profile. This would help doctors and patients set realistic, achievable weight-loss goals and better manage expectations over the long term.

While this study offered encouraging news for adults without diabetes, ongoing research will determine if tirzepatide offers similar long-term benefits for other groups. Investigations continue into differences in weight regain between genders or across age groups, offering potential for more targeted recommendations in the future.

Overall, this groundbreaking research confirms tirzepatide as an effective, long-lasting option for managing obesity and overweight. The findings reinforce that sustained, meaningful weight loss is possible for a wide range of adults, transforming expectations for obesity treatment and management.

Conflict of Interest: Professor Aronne reports receiving grants or personal fees from Eli Lilly and Company and other manufacturers of obesity and diabetes medications and treatments. All other co-authors are employees and shareholders of Eli Lilly and Company.

Note: The article above provided above by The Brighter Side of News.

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