Peptibase
Weight Loss

Retatrutide

Also known as: LY3437943, Triple G

Clinical Trials
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Key Facts: Retatrutide

Category
Weight Loss
FDA Status
Not FDA Approved
Clinical Status
Phase 3 Clinical Trials - TRIUMPH-4 (Dec 2025): 28.7% mean weight loss, highest ever in obesity trial. NDA expected Q4 2026-Q1 2027
Administration
Subcutaneous injection weekly
Typical Dose
4-12 mg weekly
Frequency
Once weekly, same day each week
Duration
Long-term use expected
Also Known As
LY3437943, Triple G

Mechanism of Action

Retatrutide activates three receptors: GLP-1 for appetite suppression and glucose control, GIP for enhanced insulin response and metabolic effects, and glucagon for increased energy expenditure and fat oxidation. The triple mechanism provides synergistic effects.

Research Summary

Phase 3 TRIUMPH-4 trial (Dec 2025) showed 28.7% weight loss at 68 weeks, with average loss of 71 lbs. Also showed significant osteoarthritis pain relief, reduced cardiovascular risk markers, and 14 mmHg blood pressure reduction. Seven more Phase 3 readouts expected in 2026. NDA submission expected late 2025/early 2026. First Phase 3 results (TRIUMPH-4, Dec 2025) showed 28.7% mean weight loss at 68 weeks with the 12mg dose — the highest ever reported in an obesity clinical trial (average 71.2 lbs / 32.3 kg lost). Seven more Phase 3 trials expected to report throughout 2026.

Trial Progress:Phase III
Pre
I
II
III
IV
FDA

Dosing Information

Human Trials·Human studies conducted, not FDA approved

Typical Dosingⓘ

Community experience

Common Dose

4-12 mg weekly

Range

1-12 mg weekly (titrate up slowly)

Frequency

Once weekly, same day each week

Triple agonist (GLP-1/GIP/glucagon). Start low (1-2 mg) and titrate up to minimize GI side effects. Not yet FDA approved but available through compounding.

Research Dosingⓘ

Scientific studies

Doses from clinical trials

Duration

Long-term use expected

Administration

Subcutaneous injection weekly

Timing & Administration

Best Time to Take

Morning, same day each week

Once weekly, same day and time

Food Recommendation

With or without food

Why This Timing?

As a triple agonist, consistent weekly timing is important. Morning allows for side effect monitoring.

Possible Side Effects

Not everyone experiences these effects. Individual responses vary based on dosage, duration, and personal factors.

  • ●Nausea (dose-related)
  • ●Diarrhea
  • ●Vomiting
  • ●Constipation
  • ●Heart rate increases
  • ●Hypersensitivity reactions
  • ●Dysesthesia - skin sensitivity/tingling (~21% at highest dose, TRIUMPH-4 data)
  • ●Pancreatitis (rare)
  • ●Currently in Phase 3 trials

References

Research This Peptide Further

PubMedClinicalTrials.govFDA.gov

Frequently Asked Questions

What does Retatrutide do?

A triple agonist targeting GLP-1, GIP, and glucagon receptors. Phase 3 trials show up to 28.7% weight loss (71 lbs average), the highest of any obesity drug. Expected FDA approval late 2026 to early 2027.

How does Retatrutide work?

Retatrutide activates three receptors: GLP-1 for appetite suppression and glucose control, GIP for enhanced insulin response and metabolic effects, and glucagon for increased energy expenditure and fat oxidation. The triple mechanism provides synergistic effects.

Is Retatrutide FDA approved?

No, Retatrutide is not currently FDA approved. Current status: Phase 3 Clinical Trials - TRIUMPH-4 (Dec 2025): 28.7% mean weight loss, highest ever in obesity trial. NDA expected Q4 2026-Q1 2027

What are the side effects of Retatrutide?

Reported side effects include: Nausea (dose-related), Diarrhea, Vomiting, Constipation, Heart rate increases. Individual responses vary based on dosage, duration, and personal health factors.

What is the typical dose of Retatrutide?

Community-reported common dose: 4-12 mg weekly (Once weekly, same day each week). Range: 1-12 mg weekly (titrate up slowly). Administration: Subcutaneous injection weekly. Community-reported doses. Not medical advice. Consult healthcare provider.

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Orforglipron

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CagriSema

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