Pharmacotherapy of Obesity: Limits and Perspectives

Obesity is a severe worldwide epidemic. Obesity comorbidities, such as type 2 diabetes mellitus, hypertension, and atherosclerosis, are costly for patients and governments. The treatment of obesity involves several facets, including lifestyle changes, bariatric surgery, and pharmacotherapy. As changes in lifestyle require considerable patient commitment that is sometimes unachievable, and surgery is expensive and invasive, pharmacotherapy is the primary option for most patients. This review describes the pharmacotherapy currently available in the USA, Europe, and Brazil, focusing on its limitations. We then analyze the results from clinical trials of new drug candidates. Most drugs cause weight loss of < 4 kg compared with controls, and severe adverse effects have caused a number of drugs to be withdrawn from the market in several countries. Drugs under development have not shown more significant weight loss or reduced adverse effects. We conclude that a significant portion of obese patients have few treatment options because of the adverse effects and minimal weight loss associated with current pharmacotherapy. However, drugs currently under development appear unable to change this scenario in the near future. Thus, it is essential that new compounds are developed and new molecular targets studied so obesity can be efficiently treated in all patients in the future.