What is Retatrutide & how does it work?

What is Retatrutide?

Retatrutide is an experimental weekly weight management injection developed by Eli Lilly, currently undergoing clinical trials for the treatment of obesity, type 2 diabetes, and potentially other metabolic conditions. The information on this page is provided for general educational purposes only and is based on publicly available information relating to ongoing clinical research.

It has been referred to as the ‘Triple G’, because, in clinical trials, it activated three hormone receptors (GLP-1, GIP, and Glucagon)

While it’s not yet approved in Ireland, Retatrutide is currently in late-stage clinical trials, with availability expected from 2026 onwards only if approved by the HPRA.

What is the active ingredient?

The active ingredient is Retatrutide. The potential brand name of the medication is not currently known as it has not been licensed in Ireland.

How does it work?

Retatrutide has a triple-action mechanism, meaning it simultaneously activates three hormone receptors:

• GLP-1 receptor
• GIP receptor
• Glucagon receptor

Does Retatrutide help you lose weight?

Retatrutide has been researched for weight management in clinical trials only. It’s a new medication still in development, and it works by mimicking three gut hormones.

What are the Retatrutide doses in clinical trials?

In clinical trials Retatrutide was administered as a once-weekly injection, and patients followed a gradual titration schedule to help minimise side effects. How does Retatrutide differ from other GLP-1s?

Retatrutide is an investigational medicine currently being studied in clinical trials. Researchers are investigating its activity at three hormone receptors:

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

By comparison, currently licensed medicines such as semaglutide (Wegovy®) and tirzepatide (Mounjaro®) act on one or two of these receptors.

As Retatrutide remains under investigation and has not been approved for use in Ireland, conclusions regarding its efficacy, or performance cannot currently be made. Information relating to Retatrutide is based on clinical research and should be considered educational in nature only.

Can anyone get Retatrutide?

Retatrutide is currently not available in Ireland. Pending trial results, if Retatrutide is HPRA approved, it is likely to be classified as a prescription-only medication, requiring a valid prescription from a healthcare provider.

Why is it called the ‘Triple G’ weight loss drug?

The nickname "Triple G" has been used in discussions about Retatrutide because researchers are studying its activity at three hormone receptors:

• GLP-1
• GIP
• Glucagon

Will Retatrutide replace Wegovy and Mounjaro?

It is not currently possible to determine the future role of Retatrutide, as it is undergoing clinical trials and has not been approved for use in Ireland.

Should Retatrutide receive regulatory approval in the future, it may become an additional treatment option. However, any decisions regarding its use and suitability for patients would depend on the evidence reviewed by regulatory authorities and healthcare professionals.

Is Retatrutide a peptide (GLP)?

Yes, Retatrutide is classified as a peptide and is a type of GLP-1 receptor agonist that is being studied in clinical trials.