Obesity

Obesity

Obesity is a chronic disease recognized by all major medical organizations, defined quantitatively as a body mass index (BMI) of 30 kg/m2 or greater. It is further classified into severity categories: Class I (BMI 30-34.9), Class II (BMI 35-39.9), and Class III or severe obesity (BMI ≥40). Obesity results from a complex interplay of genetic, environmental, behavioral, and hormonal factors that create a sustained energy imbalance, and it is associated with a significantly increased risk of type 2 diabetes, cardiovascular disease, obstructive sleep apnea, non-alcoholic fatty liver disease, osteoarthritis, and multiple forms of cancer.

The pharmacological treatment of obesity has historically been limited by modest efficacy and significant side effects. However, the advent of incretin-based therapies has fundamentally changed the treatment landscape. GLP-1 receptor agonists demonstrated that pharmacologically meaningful weight loss — defined as ≥5% of baseline body weight — could be achieved in the majority of treated patients. Retatrutide has pushed these boundaries further: in the Phase 2 trial, participants receiving the highest dose achieved mean weight reductions of approximately 24% at 48 weeks, approaching the weight loss typically seen only with bariatric surgery.

Obesity is the primary target indication for retatrutide’s clinical development program. The Phase 3 trials are evaluating the drug’s efficacy and safety in adults with obesity or overweight with at least one weight-related comorbidity. If approved, retatrutide could represent a significant advancement in obesity pharmacotherapy, offering patients a once-weekly subcutaneous injection that delivers weight loss of a magnitude previously attainable only through surgical intervention.