Long-term weight loss maintenance is seldom achieved by individuals with obesity owing to numerous biological adaptations involving appetite, satiety, and energy expenditure in the post- weight loss setting. Following a loss in body weight, peripheral and central mechanisms convey a sense that energy reserves have dwindled, activating a strong counter response to increase caloric intake. Adolescents with severe obesity are not immune to the vexing issue of weight regain. Indeed, only 2% are able to achieve and maintain clinically- meaningful weight loss with lifestyle modification therapy. Therefore, novel treatment paradigms focused on long-term weight loss maintenance are urgently needed. Pharmacotherapy has the potential to prevent weight regain by targeting specific counter-regulatory mechanisms in the post- weight loss setting. One of the most promising candidates is the glucagon like peptide-1 receptor agonist (GLP-1RA) class, which greatly enhanced weight loss maintenance following a short-term low calorie diet among adults with obesity. The rationale for focusing on GLP-1RA treatment to prevent weight regain is supported by the multiple central and peripheral mechanisms of action targeted by this class of drug; many of which specifically address the biological adaptations known to induce relapse. We have strong preliminary data demonstrating that GLP-1RA treatment reduces BMI in adolescents with severe obesity. Moreover, we and others have shown that although meal replacement therapy (structured meals of known caloric content) can elicit robust short-term weight loss among adolescents with severe obesity, weight regain is a pervasive problem. Therefore, in this clinical trial, our innovative approach will utilize GLP-1RA treatment to target weight regain following short-term meal replacement therapy in youth with severe obesity. Participants who achieve =5% BMI reduction during the meal replacement phase will be randomized to GLP-1RA treatment or placebo for an additional 12 months while simultaneously engaging in lifestyle modification therapy. Importantly, this study will also allow us to examine the extent to which GLP-1RA treatment addresses mechanisms of weight regain, investigate other pleiotropic benefits of GLP-1RA, and identify predictors of weight loss response. This research tackles a significant public health threat, utilizes an innovative treatment concept and approach, and exerts a powerful, sustained influence on the field of pediatric obesity by steering research and clinical practice paradigms toward the application of pharmacotherapy for meaningful and durable weight loss and risk factor modification.
This randomized, double-blind, placebo-controlled, clinical trial will assess the ability of a new weight loss medication to improve the durability of weight loss among adolescents with severe obesity.