The Incretin Revolution: Transforming Metabolic Medicine Review Article

Background: The class of drugs known as glucagon-like peptide-1 receptor agonists (GLP-1 RAs) has significantly changed how type 2 diabetes mellitus (T2DM) and obesity are treated. Since the 1980s, when the role of incretins was first discovered, and up to the recent approval of drugs that combine multiple active ingredients, this development has been one of the most important achievements in modern endocrinology.
Methods: This review provides an overview of key randomized controlled trials, regulatory documents, and new drug development data for both peptide and non-peptide GLP-1 RAs.
It evaluates their effectiveness, impact on cardiovascular health, side effects, and areas where more research is needed.
Results: GLP-1 RAs consistently lower HbA1c levels by 1 to 2 percent, reduce body weight by 5 to 22 percent, and decrease the risk of major cardiovascular events by 9 to 20 percent.
Newer drugs, such as poly-agonists like tirzepatide and retatrutide, and orally available small molecules like orforglipron, are expanding the range of treatment options.
Conclusions: GLP-1 based treatments have the potential to tackle both type 2 diabetes and obesity, but issues like cost, tolerability, and long-term safety continue to pose challenges.

GLP-1 receptor agonist; incretin; semaglutide; tirzepatide; obesity; type 2 diabetes; cardiovascular outcomes; non-peptide oral agonist

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