In a recent study published on December 11, 2023, in the Journal of the American Medical Association, researchers delved into the effects of tirzepatide, a newly approved obesity drug in the United States, shedding light on the long-term implications of its usage. The study involved 670 adults who, after nine months of weekly tirzepatide injections, experienced a notable average weight loss of 20.9%. Subsequently, the participants were divided into two groups: one continued with the drug, while the other received a placebo. The results after 22 months were revealing. Those on the placebo regained nearly half of the weight lost, settling at 9.9% below their baseline. Meanwhile, the tirzepatide group sustained their weight loss momentum, concluding 25.3% lower than their initial weight. This research suggests that while obesity drugs may induce significant weight loss, discontinuing treatment might lead to a rebound effect, emphasizing the potential for long-term dependence on such medications.
The study participants, predominantly women with an average age of 48 and an initial average weight of 107.3 kilograms, were engaged in a research endeavor examining the effects of tirzepatide, a recently approved obesity drug. During the nine-month study period, participants were advised to consume 500 fewer calories per day than they burned and engage in at least 150 minutes of weekly exercise. Common side effects noted in the study included gastrointestinal issues like nausea, diarrhea, constipation, and vomiting. The research, led by Professor Dr. Louis Aronne at Weill Cornell Medicine in New York, underscores the importance of sustained pharmacotherapy to prevent weight regain and ensure the maintenance of weight reduction. This study contributes to existing evidence from four previous trials, indicating substantial weight regain post-treatment cessation with anti-obesity medications such as semaglutide. Both semaglutide and tirzepatide belong to the GLP-1 agonist class, mimicking a hormone’s function that regulates insulin secretion, slows stomach emptying, and suppresses appetite. Tirzepatide, additionally, incorporates a molecule resembling the gut hormone GIP. In response to the findings, Eli Lilly, the pharmaceutical company manufacturing tirzepatide, emphasized the chronic nature of obesity, highlighting the need for ongoing treatment even after achieving weight goals. While GLP-1 agonists demonstrate a reduced risk of obesity-related heart disease, they also elevate the risk of gastrointestinal problems. Concerns linger about the potential long-term impact of these drugs, given their associated costs and the need for extended usage. Currently, tirzepatide in the U.S. comes with a monthly cost of US$1,059.87.
