Tirzepatide vs Retatrutide: complete comparison for research 2026
The question “Retatrutide or Tirzepatide?” is one of the most frequent among researchers and professionals studying peptides related to metabolism. Both compounds belong to the new generation of incretin-like peptides and share a common mechanism, but have fundamental differences that are important to know in order to design appropriate research protocols.
In this complete comparison we analyze Tirzepatide vs RetatrutideThe following information is available: mechanism of action, published clinical data, presentations available in Colombia, approximate prices and how to choose which one to study according to the objective of your research.
Quick summary: Tirzepatide is an agonist dual (GLP-1 + GIP); Retatrutide is an agonist. triple (GLP-1 + GIP + glucagon). Retatrutide adds the activation of the glucagon receptor, which in preclinical models could amplify the effects on lipid metabolism. In Colombia both are available in multiple presentations. Distribution exclusively for scientific research purposes.
Comparative mechanism of action
The fundamental technical difference lies in the hormone receptors that activate each peptide:
| Feature | Tirzepatide | Retatrutide |
|---|---|---|
| Type of agonist | Dual | Triple |
| GLP-1 Receptor | ✓ Yes | ✓ Yes |
| GIP Receiver | ✓ Yes | ✓ Yes |
| Glucagon receptor | ✗ No | ✓ Yes |
| Year of FDA approval | 2022 (Mounjaro) | In phase 3 (2026) |
| Developer | Eli Lilly | Eli Lilly |
| Typical frequency in studies | Weekly | Weekly |
The glucagon agonism added in Retatrutide is the most differentiating element. While GLP-1 and GIP are mainly associated with appetite regulation and insulin sensitivity, glucagon activation is related to energy mobilization and lipid metabolism. This “three-dimensional” action is the basis for the hypothesis that Retatrutide could have amplified effects on body composition under investigation.
Published clinical studies
Both compounds have data published in high impact journals. A brief overview of the state of research at the time of writing:
Tirzepatide
- SURPASS (type 2 diabetes): series of pivotal trials leading to FDA approval in 2022.
- SURMOUNT (obesity): trials documenting significant body weight loss in study subjects, leading to approval for this indication in 2023.
- Multiple publications in The New England Journal of Medicine y JAMA.
Retatrutide
- Phase 2 in obesity: published in The New England Journal of Medicine in 2023. Preliminary data suggested comparable or superior results to Tirzepatide in terms of change in body composition.
- TRIUMPHPhase 3 testing program in progress at the time of writing.
- Complementary studies on insulin sensitivity and lipid metabolism.
It is important to remember that the Tirzepatide is now a marketed drug in several countries, while the Retatrutide is still an investigational compound. in most jurisdictions. In Colombia, both are distributed exclusively for scientific research purposes.
Presentations available in Colombia
Tirzepatide
| Presentation | Format |
|---|---|
| Tirzepatide 15 mg | Lyophilized vial |
| Tirzepatide 30 mg | Lyophilized vial |
| Tirzepatide 40 mg | Lyophilized vial |
| Tirzepatide 60 mg | Lyophilized vial |
Retatrutide
| Presentation | Format |
|---|---|
| Retatrutide 10 mg | Lyophilized vial |
| Retatrutide 15 mg | Lyophilized vial |
| Retatrutide 30 mg | Lyophilized vial |
| Retatrutide 40 mg | Lyophilized vial |
| Retatrutide 50 mg | Lyophilized vial |
| Retatrutide 20 mg in pen | Pre-filled pen |
Which one to choose for research?
The choice depends on the objective of the study. The following is a guideline:
| Research objective | Best candidate | Reason |
|---|---|---|
| Replicating existing literature on GLP-1/GIP | Tirzepatide | More published studies, well-characterized dual mechanism |
| Research triple action on metabolism | Retatrutide | Only triple agonist currently available |
| Comparability with marketed clinical data | Tirzepatide | Already FDA approved, abundant clinical literature |
| Body composition and lipid studies | Retatrutide | Potentially relevant added glucagon mechanism |
| Insulin sensitivity research | Both | Published data for the two compounds |
Reconstitution (common procedure)
Both peptides are delivered lyophilized and require reconstitution with bacteriostatic water prior to their use in research. The procedure is the same for both:
- Hand and work surface hygiene.
- Disinfection of stoppers with 70% alcohol.
- Load the syringe with the chosen volume of bacteriostatic water.
- Injection at a 45° angle against the inner wall of the vial - not on the powder.
- Gentle dissolution by gravity. Do not shake.
- Wait 2-3 minutes until clear solution.
- Labeled with date and resulting concentration.
- Refrigeration at 2-8°C. Shelf life after reconstitution: up to 45 days.
For customized concentration calculations according to the chosen vial, you can use our peptide calculator.
Frequently Asked Questions
Which is more potent, Tirzepatide or Retatrutide?
Preliminary phase 2 data suggest that Retatrutide may produce more marked changes in body composition in certain models, but the “potency” depends on the parameter assessed and the phase of the study. Rigorous direct comparison is still under development in clinical trials.
Are both approved in Colombia?
No. Neither of them is approved by Invima as a prescription drug. In Colombia they are distributed exclusively for scientific research purposes.
Do they have the same developer?
Yes, both were developed by Eli Lilly. Tirzepatide is marketed under the name Mounjaro/Zepbound; Retatrutide is still identified as LY3437943 in scientific publications.
How long do they last when reconstituted?
Both peptides, once reconstituted with bacteriostatic water and stored refrigerated at 2-8°C, last up to 45 days.
How long does shipping take in Colombia?
Between 24 and 72 business hours for major cities (Bogota, Medellin, Cali, Barranquilla, Cartagena). Up to 5-7 business days for remote areas.
In a nutshell
Tirzepatide and Retatrutide represent two consecutive generations of incretin-like peptides developed by Eli Lilly. The choice between one or the other for research depends on the focus of the study: Tirzepatide offers more published literature and a well-characterized pharmacological profile; Retatrutide offers the only GLP-1/GIP/glucagon triple mechanism available and promising preliminary data.
To learn more about each compound, please consult our dedicated guides: Retatrutide Guide in Colombia, or directly explore the available presentations at Peptilife with fast shipping and discreet packaging.
Important notice: All information in this article is provided solely for educational and informational purposes on research peptides. Tirzepatide and Retatrutide are compounds analyzed here in a research context; in Colombia they are distributed in the following countries exclusively for scientific research purposes. They do not constitute medical advice, do not replace a varied and balanced diet and a healthy lifestyle. In case of pregnancy, breastfeeding or use of medication, always consult a health professional before any use.