GLP1R and obesity due to melanocortin 4 receptor deficiency: The search strategy incorporated key terms such as "GLP-1," "GLP-1 receptor agonists," "weight loss," "obesity," "type 2 diabetes," "mechanism of action," "clinical efficacy," "safety," and "future trends." To ensure the inclusion of the most current information, we primarily focused on literature published within the last 20 years (2004-2024), although seminal papers from earlier dates were included when relevant to the historical context or fundamental understanding of GLP-1-RAs.