Weight management treatment in obesity.
This review examines the evolving pharmacological landscape for obesity management, with a focus on gut-brain axis hormones and their therapeutic potential. The authors describe how nutrient-stimulated gastroenteropancreatic hormones — including GLP-1, GIP, glucagon, and amylin — have become central targets in obesity drug development. The review covers both marketed agents and those in ongoing clinical trials. GLP-1 receptor agonists (e.g., weekly injectable or daily oral semaglutide) are reported to achieve roughly 15–17% weight loss with a favorable safety profile. The dual GLP-1/GIP agonist tirzepatide is described as achieving up to approximately 22.5% weight loss at higher doses. Combination therapies under investigation — such as cagrilintide plus semaglutide (Cagrisema), GLP-1/glucagon co-agonists, and the triple agonist retatrutide (GLP-1/GIP/glucagon) — are noted as potentially reaching weight loss comparable to bariatric surgery. The review also discusses cardiometabolic benefits and challenges around long-term treatment adherence for both patients and clinicians. As a narrative review, it synthesizes existing trial data rather than generating new primary evidence, and conclusions depend on the quality of the underlying studies cited.
Why this grade: This is a narrative review synthesizing existing clinical trial data rather than presenting original primary research, so it is graded as review-level evidence.
Obesity is a chronic and relapsing disease associated with medical complications and mortality. Our improved understanding of the relevance of the gut-brain axis in regulating appetite and body weight has encouraged research into nutrient-stimulated gastroenteropancreatic hormones as a new therapeutic arsenal for the treatment of people living with obesity. Beyond the necessary lifestyle changes, this new era with second-generation drugs has been able to achieve weight loss of 15-25%, close to that of bariatric surgery. Glucagon-like peptide-1 (GLP-1) receptor agonists (RA), used as weekly injectable monotherapy or daily oral (semaglutide), achieve weight loss of 15-17%, with a good safety profile. The synergistic combination with other hormones (such as glucose-dependent insulinotropic polypeptide (GIP), glucagon, or amylin) will allow to increase weight loss, as well as improve cardiometabolic variables. Tirzepatide (a dual GLP-1/GIP receptor agonist) achieves weight loss of up to 22.5% at the highest doses. In this same range of weight loss, it is expected that it can be achieved with the combination of Cagrisema (cagrilintide 2.4mg plus semaglutide 2.4mg), combinations of GLP-1 RAs - glucagon agonists or with the triple combination of GLP-1 RAs-GIP-Glucagon (Retatrutide). In this review, we will examine the efficacy and safety of the drugs marketed and others under ongoing clinical trials for the treatment of persons with obesity, as well as the main challenges faced by both healthcare professionals and patients in maintaining long-term treatment.
Educational summary of published research — not medical advice. Full text is shown only where licensing permits.