Tirzepatide, a once-weekly GIP/GLP-1 receptor agonist, has been shown to be effective in weight reduction in adults with obesity, with a recent analysis of the SURMOUNT clinical trials demonstrating significant weight loss when administered as a once-weekly injection. Women experienced greater weight loss compared to men, with reductions of up to 24.6% of body weight for women and 18.1% for men. Obesity affects around 650 million adults globally, and drugs targeting specific hormones involved in energy balance, such as GLP-1, have been shown to be effective and safe for weight loss. Tirzepatide, which targets both GIP and GLP-1 receptors, has shown promise for weight loss in individuals with type 2 diabetes, and early research in mice indicated greater weight loss compared to treatments targeting only GLP-1.
The SURMOUNT program included four clinical trials (SM-1 to SM-4) that evaluated the effectiveness of tirzepatide for weight loss in adults with obesity or overweight who do not have diabetes. A post-hoc analysis of the trials showed that tirzepatide injections resulted in significant weight loss for both men and women, with women experiencing greater reductions in weight. The analysis, presented at the EASD Annual Meeting in Madrid, included 4,677 adults, with tirzepatide leading to greater body weight reduction in females compared to males. Logistic regression was used to assess specific weight loss milestones achieved by participants, with women generally experiencing higher rates of weight loss compared to men across all doses of tirzepatide.
While women made up the majority of participants in the trials and weighed less than men at the start, they had similar levels of obesity in terms of BMI. Both men and women achieved significant weight loss with tirzepatide compared to placebo, with women seeing a greater percentage of weight reduction across all doses. However, there were no significant differences between men and women in achieving specific weight loss thresholds in most trials. Safety outcomes were generally similar for both sexes, though women reported higher rates of nausea and vomiting compared to men. Results of this post-hoc analysis are hypothesis-generating and require further research to understand the potential mechanisms behind the findings.
The study findings on body weight reduction with tirzepatide are promising and in alignment with clinical observations, suggesting the potential for more personalized treatment plans based on demographics. These insights may lead to more tailored and effective weight loss solutions, ultimately improving long-term health outcomes. Further research in this area could help prescribing providers set realistic expectations based on gender for patients seeking these medications. This research highlights the importance of considering potential sex-based differences in drug response and the need for additional studies to explore the mechanisms behind these findings.
