New therapies for obesity

Obesity is a chronic disease associated with serious complications and increased mortality. Weight loss through lifestyle changes results in modest weight loss long-term possibly due to compensatory biological adaptations (increased appetite and reduced energy expenditure) promoting weight gain. Bariatric surgery was until recently the only intervention that consistently resulted in ≥ 15% weight loss and maintenance. Our better understanding of the endocrine regulation of appetite has led to the development of new medications over the last decade for treatment of obesity with main target the reduction of appetite. The efficacy of semaglutide 2.4 mg/week - the latest glucagon like peptide-1 (GLP-1) receptor analogue - on weight loss for people with obesity suggests that we are entering a new era in obesity pharmacotherapy where ≥15% weight loss is feasible. Moreover, the weight loss achieved with the dual agonist tirzepatide (GLP-1/glucose-dependent insulinotropic polypeptide) for people with type 2 diabetes and most recently also obesity, indicate that combining the GLP-1 with other gut hormones may lead to additional weight loss compared to GLP-1 receptor analogues alone and in the future, multi-agonist molecules may offer the potential to bridge further the efficacy gap between bariatric surgery and the currently available pharmacotherapies. This article provides a review of the currently available interventions for weight loss and weight maintenance with a focus on pharmacological therapies for obesity approved over the last decade, as well as the emerging development of new obesity pharmacotherapies.