The expanding therapeutic profile of GLP-1 receptor agonists and next-generation multiagonists is forcing a fundamental rethink of obesity pharmacology — these agents are no longer simply weight-loss tools but may function as broad-spectrum disease-modifying therapies with effects that appear partially independent of adiposity reduction itself.
This comprehensive review in The Lancet Diabetes & Endocrinology synthesizes evidence from randomized controlled trials and high-quality meta-analyses across a remarkable breadth of obesity-related conditions. Agents evaluated span the full current pipeline: older combination therapies such as phentermine-topiramate and naltrexone-bupropion, established GLP-1 receptor agonists including liraglutide and both subcutaneous and oral semaglutide, and emerging multiagonist compounds — tirzepatide, survodutide, mazdutide, retatrutide, cagrilintide-semaglutide, and amycretin. The review maps therapeutic effects across type 2 diabetes, metabolic dysfunction-associated steatotic liver disease (MASLD), chronic kidney disease, heart failure, cardiovascular disease, obstructive sleep apnea, polycystic ovary syndrome, osteoarthritis, muscle mass preservation, depression, food cravings, binge-eating disorder, substance use disorders, and neurodegenerative disease — thirteen distinct condition domains in total. A central finding is that accumulating evidence points to meaningful weight-loss-independent mechanisms, especially with GLP-1 receptor agonists.
The weight-loss-independent signals are arguably the most scientifically significant element here. Mechanistically, GLP-1 receptors are expressed in the heart, kidney, liver, brain, and immune cells, providing plausible pathways for direct organ-level effects separate from adipose reduction. The cardiovascular outcome data for semaglutide (SELECT trial) and tirzepatide's effects on heart failure with preserved ejection fraction already hint at this. The neuropsychiatric signals — depression, addiction, and potentially neurodegeneration — are particularly intriguing and less understood. Key limitations apply: many condition-specific findings rest on secondary endpoints of trials powered for metabolic outcomes; long-term durability and safety data for newer multiagonists remain immature; and effect sizes in non-metabolic domains are generally modest. This review is confirmatory and consolidating for cardiovascular and metabolic indications, but potentially paradigm-shifting in framing obesity pharmacotherapy as systemic disease modification.