GLP1R and obesity due to melanocortin 4 receptor deficiency: The FDA approved GLP-1 agonists for obesity and type 2 diabetes treatment with mounting evidence in reducing the reward effects and hyperphagia-induced body weight gain following illicit drugs and nicotine quitting (Chinn et al., 2005; Mills et al., 2012; Davies et al., 2021; Herman et al., 2023).