Retatrutide Facts

What is Retatrutide?

Retatrutide (LY3437943) is an investigational synthetic peptide developed by Eli Lilly. It is the first advanced clinical-stage triple hormone receptor agonist, designed to activate:

• GLP-1 (Glucagon-Like Peptide-1) receptors
• GIP (Glucose-Dependent Insulinotropic Polypeptide) receptors
• Glucagon receptors

Because it simultaneously targets all three pathways, retatrutide is commonly referred to as a triple agonist. It is currently being investigated as a once-weekly subcutaneous injection for obesity, type 2 diabetes, and several obesity-related conditions. It has not been approved by the U.S. FDA.

Basic Information

• Compound Class: Synthetic peptide
• Administration: Once-weekly subcutaneous injection (investigational)
• Naturally Occurring: No
• Primary Targets:
  • GLP-1 receptor
  • GIP receptor
  • Glucagon receptor
• Primary Research Areas:
  • Obesity
  • Weight management
  • Type 2 diabetes
  • Metabolic dysfunction
  • Cardiovascular risk
  • Liver disease
  • Obstructive sleep apnea

Mechanism of Action

Retatrutide combines the activity of three naturally occurring metabolic hormones into a single molecule.

Researchers believe each receptor contributes distinct physiological effects:

GLP-1 Receptor Activation

Research has shown GLP-1 receptor activation may:

• Increase satiety
• Slow gastric emptying
• Reduce appetite
• Improve glucose regulation

GIP Receptor Activation

GIP receptor activation has been investigated for its potential effects on:

• Glucose metabolism
• Insulin secretion
• Energy balance
• Adipose tissue biology

Glucagon Receptor Activation

Unlike currently approved GLP-1 therapies, retatrutide also activates glucagon receptors.

Researchers believe glucagon receptor activity may contribute to:

• Increased energy expenditure
• Enhanced fat oxidation
• Thermogenesis
• Reduced hepatic fat accumulation

The combination of these three pathways is believed to underlie retatrutide's investigational metabolic effects.

Areas of Research

Obesity

Retatrutide is primarily being investigated as a treatment for obesity.

Large Phase 2 and Phase 3 studies have evaluated:

• Total body weight reduction
• Waist circumference
• Body composition
• Cardiometabolic risk factors

Phase 3 studies have reported average weight reductions approaching 28% at the highest investigational dose over approximately 80 weeks, although regulatory review is ongoing.

Type 2 Diabetes

Researchers are studying retatrutide for:

• Glycemic control
• HbA1c reduction
• Insulin sensitivity
• Weight reduction in individuals with diabetes

Phase 3 clinical trials have reported improvements in both blood glucose control and body weight in adults with type 2 diabetes.

Liver Disease

Retatrutide is being investigated in individuals with:

• Metabolic dysfunction-associated steatotic liver disease (MASLD)
• Excess liver fat accumulation

Researchers are evaluating whether improvements in weight and metabolism translate into improved liver health.

Cardiovascular Disease

Clinical trials are evaluating retatrutide in people with established cardiovascular disease to determine its effects on cardiovascular outcomes alongside weight reduction.

Obstructive Sleep Apnea

Because obesity contributes to obstructive sleep apnea (OSA), retatrutide is also being studied for its potential impact on OSA severity in adults with obesity.

Human Research

Retatrutide has been evaluated in multiple Phase 2 and Phase 3 clinical trials.

Research has demonstrated:

• Significant body weight reduction
• Improvements in blood glucose
• Improvements in several cardiometabolic biomarkers

The medication remains investigational, and additional studies are ongoing to better characterize its long-term safety and efficacy across multiple disease states.

Research Use Only: This product is intended exclusively for laboratory and scientific research by qualified professionals. It is not intended for human or veterinary use, diagnosis, treatment, cure, or prevention of any disease. This product has not been evaluated or approved by the U.S. Food and Drug Administration (FDA). Handle and store in accordance with applicable laboratory safety procedures.