GLP1R and obesity due to melanocortin 4 receptor deficiency: As GLP-1R agonists like liraglutide and semaglutide have shown very promising results in clinical studies, the development of dual- and tri-agonists, which also have agonist effects on glucagon-receptors, holds immense promise to improve metabolic outcomes for people with obesity, T2DM or liver diseases [248].