Retatrutide

Overview

What is Retatrutide?

Retatrutide is an investigational triple agonist acting at the GLP-1, GIP and glucagon receptors, developed by Eli Lilly for obesity and metabolic disease. It is not approved by any regulator and is legally available only through its clinical trial programme.

• Weight Management
• Appetite Control
• Metabolic Health
• Liver Fat

What the research reports

Reported benefits of Retatrutide

Outcomes described across the published Retatrutide literature and ongoing study. Read each as research context, not a promised result.

1. 01

   Large weight loss in trials

   Phase 2 work reported dose dependent weight loss up to 24.2 percent at 48 weeks against 2.1 percent on placebo in adults with obesity. Reported in research settings.

2. 02

   Triple receptor activation

   Activates GLP-1 for appetite control, GIP for metabolic efficiency and glucagon for energy expenditure simultaneously, a broader reach than dual agonists.

3. 03

   Glycaemic control research

   Phase 2 trials in type 2 diabetes reported HbA1c reductions up to 2.02 percent alongside meaningful reductions in body weight. Reported in research settings.

4. 04

   Liver fat reduction study

   A phase 2a trial in 98 patients with fatty liver disease reported liver fat down up to 82.4 percent at 24 weeks, with 86 percent reaching normal liver fat.

5. 05

   Body composition change data

   A 2025 analysis reported total body fat mass reduced by 15 to 26 percent against placebo in people with type 2 diabetes. Reported in research settings.

Dosage and protocol

Retatrutide dosage and protocol

Trial protocols titrate from 1 mg weekly through 2, 4 and 8 mg to a 12 mg target, escalating every four weeks. The half-life is approximately six days at steady state dosing.

Route

Subcutaneous injection

Example range

1-12 mg

Frequency

Once weekly

Timing

Once weekly, same day. Escalate every four weeks to limit nausea.

Clinical evidence

Clinical evidence for Retatrutide

The published record for Retatrutide, labeled by strength so you can see what is settled and what is emerging.

Interactions

How it pairs with other peptides

Semaglutide

Overlapping GLP-1 activity. Combining raises gastrointestinal burden with no established added benefit.

Tirzepatide

Overlapping GLP-1 and GIP activity. The two are not combined in any clinical protocol. Confidence: emerging.

Insulin therapy

Glucose lowering effects stack, so hypoglycaemia risk rises when incretin therapy is added to insulin.

Sulfonylureas

Added glucose lowering raises hypoglycaemia risk and usually calls for a dose review by a clinician.