The Peptide Desk The Peptide Desk

This information is for research and educational purposes only. No medical recommendations. Products are not approved for human use. For health questions, consult a doctor.

Lexicon
Weight management

Reta + Tesamorelin Blend

An injectable experiment built from two peptides in one vial - no human data on the combination, no established dosing.

5 min read 15 sources

To the product To the calculator
Reta plus Tesamorelin Blend vial with white powder and the black TPD label on a white podium, next to two blue 3D peptide chains in a bright lab
Retatrutide in phase 3 · not approved

Summary

At a glance

Sources checked on 26 Oct 2026

On the blend
0 trials

no trial with Retatrutide and tesamorelin together, as of 26 Oct 202613

Retatrutide alone, phase 2
-24.2 %

Body weight at 48 weeks, highest study dose (placebo -2.1%)1

Tesamorelin alone, belly fat
-15.4 %

visceral fat at 26 weeks, difference from placebo, 806 patients with HIV4

Phase 3 of the components
16 trials

14 with Retatrutide, 2 with tesamorelin, as of 26 Oct 202612

  • The blend combines Retatrutide (a triple agonist at GLP-1, GIP and glucagon) and tesamorelin (an analogue of the hormone GHRH) in a fixed 1:1 ratio.1415
  • There is no study of the blend. All figures come from studies of the components, which were given separately and on their own schedules: Retatrutide once a week, tesamorelin daily.1313
  • Retatrutide alone lowered body weight by 24.2 percent after 48 weeks at the highest study dose in phase 2. A meta-analysis with 878 participants found on average 14.33 percentage points more loss than on placebo.12
  • Tesamorelin lowered visceral fat in HIV with excess belly fat by 15.4 percent more than placebo in 26 weeks. It has been approved for this in the USA since 2010.411
  • Retatrutide is not approved (phase 3). Everything here is the state of research, not a recommendation.14
Profile

Updated June 2026

Type
Injectable blend

triple agonist + GHRH analog

Route
Subcutaneous, reconstituted

lyophilizate

Evidence
No human data for the combination
Vial
20 mg per vial

10 mg reta + 10 mg tesa, 10 vials

Sizes
20 mg

1 size in the shop

Contents 14 sections
  1. At a glance
  2. What is Reta + Tesamorelin Blend?
  3. How it works
  4. Application and reconstitution
  5. Dosing
  6. What the research shows
  7. Research status
  8. Side effects
  9. Practice
  10. Storage
  11. Related compounds
  12. FAQ
  13. Glossary
  14. Sources

Equipment

Equipment you need

For reconstitution and injection you need a bit of basic gear. Here are solid, cheap options:

U-100 insulin syringes Fine needle, 1ml, for subcutaneous use View on Amazon Alcohol swabs To disinfect the vial top and injection site View on Amazon

As an Amazon associate we earn from qualifying purchases. Links open Amazon - no extra cost for you.

What is Reta + Tesamorelin Blend?

This is an injectable blend of two very different research compounds: Retatrutide (a GLP-1/GIP/glucagon triple agonist from metabolic research) and Tesamorelin (a GHRH analog meant to nudge the body's own growth-hormone release). Both have their own lexikon entries as single originals - that is where the solid evidence lives.

Honest framing up front: this is an experimental construct. It ships as a freeze-dried powder that you reconstitute with bacteriostatic water and inject subcutaneously - the same route on which both compounds were given in the studies. The catch is the fixed 1:1 mix (10 mg reta + 10 mg tesa per vial): the two peptides have completely different typical weekly doses, so one shared dose never fits both at once. There is no human study on this exact combination - neither for efficacy nor for the ideal dose. What you read here contextualizes the pharmacology, but it cannot substitute for combination data that simply does not exist.

This information is for research and educational purposes only. No medical recommendations.

Comparison

Metabolism and growth hormone axis

Which receptors each compound targets, as stated in the TPD lexicon. Tap a card to open its entry.

Dual agonist Tirzepatide GLP-1 GIP Glucagon GHRH 2 of 4 receptors Triple agonist Retatrutide GLP-1 GIP Glucagon GHRH 3 of 4 receptors GHRH analogue Tesamorelin GLP-1 GIP Glucagon GHRH 1 of 4 receptors
Triple agonist plus GHRH analogue Reta + Tesamorelin Blend GLP-1 GIP Glucagon GHRH 4 of 4 receptors

Simplified: the two components act on completely different systems. The blend itself has not been studied. 101415

How it works

On paper these are two completely separate mechanisms:

  • Retatrutide activates three receptors at once - GLP-1, GIP and glucagon. Studies point to appetite suppression, slowed gastric emptying and increased energy expenditure via the glucagon arm.
  • Tesamorelin mimics GHRH and is meant to prompt the pituitary to release growth hormone in pulses, which raises IGF-1 levels. In a research context it has mainly been linked to reduction of visceral abdominal fat.

The crucial catch with the fixed mix: reta already works in the range of a few milligrams per week, whereas tesamorelin is given in studies in the milligram range per day. In a 50/50 vial you cannot hit both in their sensible range at the same time - dose for reta and the tesa amount is low; dose for tesa and the reta amount quickly gets too high. Pharmacologically this blend is therefore a compromise, not an optimized combination product.

Where it acts

Where the components act

Tap a point or a card. Colour = receptor, grey = seen in studies. All from studies of the components, not of the blend.

  1. Brain

    Lower food intake via Retatrutide (animal models)10

    GLP-1GIP
  2. Liver

    Liver fat dropped sharply on Retatrutide (substudy)8

    Glucagon
  3. Belly fat

    Visceral fat fell on tesamorelin, subcutaneous fat barely changed (HIV)4

    Observed in trials
  4. Blood values

    IGF-1 rose on tesamorelin, blood sugar stayed stable in the trials4

    GHRH
  5. Heart

    Heart rate rose slightly on Retatrutide, dose-dependent1

    Observed in trials

Targets in the ChEMBL database14

Compound CHEMBL5095485 + CHEMBL1237026: four recorded mechanisms, type of action on each card.

GLP-1 receptor (Retatrutide)
Gene
GLP1R
UniProt
P43220
ChEMBL
CHEMBL1784
Action
Agonist, direct binding
GIP receptor (Retatrutide)
Gene
GIPR
UniProt
P48546
ChEMBL
CHEMBL4383
Action
Agonist, direct binding
Glucagon receptor (Retatrutide)
Gene
GCGR
UniProt
P47871
ChEMBL
CHEMBL1985
Action
Agonist, direct binding
GHRH receptor (tesamorelin)
Gene
GHRHR
UniProt
Q02643
ChEMBL
CHEMBL2032
Action
Agonist, mechanism in ChEMBL
Abstract illustration: on the left a cluster of glass cells with blue molecule chains docking on their receptors, on the right a glass cell releasing small spheres
Two separate pathways: metabolism and growth hormone. Symbolic image.

Application and reconstitution

Dosing. Loading the dosing information …

Dosing

Dosing

Dosing, titration and syringe

Loading the dosing information …

  • Getting started and stepping up, drawn as a staircase
  • Units on the U-100 syringe for every step
  • How long one vial lasts

What the research shows

For the combination itself there is nothing - no clinical trials, no pharmacokinetic data, no efficacy evidence for this exact reta-plus-tesa vial. That has to be stated plainly.

What does exist is robust data on the single originals (each subcutaneous):

  • Retatrutide: In a 48-week phase 2 trial (subcutaneous, weekly), the highest dose produced a mean weight reduction of around 24% versus placebo. A meta-analysis across 878 patients confirmed marked effects on weight and metabolic parameters.
  • Tesamorelin: Phase 3 trials in patients with visceral fat accumulation showed a roughly 15 to 18% reduction in visceral fat over 6 to 12 months (subcutaneous, daily), plus a rise in IGF-1, with generally good tolerability.

These findings are for each mono-application at its own study-typical dose. Whether a fixed 50/50 mix, in which neither runs in its ideal range, delivers the same effects is an open question.

Study results

What the trials measured

Interactive: switch tabs, tap points, show or hide arms. Arms are named relative to each other, no dosing advice.

Body weight over 48 weeks, Retatrutide alone1

Mean change in percent, phase 2 trial with 338 participants

0-5%-10%-15%-20%-25% Week 0Week 24Week 48 -2.1%-8.7%-17.1%-22.8%-24.2%

Placebo: Week 0 0.0%, Week 24 -1.6%, Week 48 -2.1%. Retatrutide level 1 (lowest): Week 0 0.0%, Week 24 -7.2%, Week 48 -8.7%. Retatrutide level 2: Week 0 0.0%, Week 24 -12.9%, Week 48 -17.1%. Retatrutide level 3: Week 0 0.0%, Week 24 -17.3%, Week 48 -22.8%. Retatrutide level 4 (highest, 12 mg): Week 0 0.0%, Week 24 -17.5%, Week 48 -24.2%.

Only the time points reported in the abstract are shown (weeks 0, 24 and 48). Levels 2 and 3 each combine two groups with a different starting dose. Trial with Retatrutide alone, not with the blend.

Visceral belly fat, tesamorelin alone34

Mean change in percent, measured by CT, patients with HIV and excess belly fat

Phase 3 trial, 26 weeks3
Placebo -0.6%
Tesamorelin -10.9%
Continued on tesamorelin to week 524 Group that received tesamorelin throughout, both trials combined
Tesamorelin -17.5%

Values from the abstracts. Those who switched to placebo after 26 weeks quickly lost the effect again. Tesamorelin was given daily, without Retatrutide.

Clear glass liver and a yellow fat tissue lobule in a glass display case on a white pedestal in a bright lab
Studies exist only for the components. Symbolic image.

Research status

Where the research stands

There is no registered trial of the blend. Listed here are the trials of both components with status, participants and results. As of 26 Oct 2026. 12

  1. Preclinical Cell assays and animal models of the components
  2. Phase 1 2 trials on components, 2 completed
  3. Phase 2 4 trials on components, 4 completed
  4. Phase 3 16 trials on components, 7 completed
  5. Approval not yet
21,539 participants in phase 3 Planned figures for running trials No approval for the blend. Tesamorelin has been approved in the USA since 2010, only for excess belly fat in HIV with lipodystrophy. Retatrutide is not approved, ChEMBL lists it with phase 3 as the highest phase.14
Show all 20 phase 2 and 3 trials on a timelineHide timeline 11 completed 9 running 5 with results
Phase 2
Phase 3

Bar: start to primary endpoint (planned for running trials). Green = completed, blue = progress until 26 Oct 2026. Phase 1: 2 trials on safety and pharmacokinetics, not shown as bars.

Side effects

Because there is no data on the combination, side effects can only be inferred from the single originals:

  • From the retatrutide arm (GLP-1/GIP/glucagon): In the studies, gastrointestinal effects dominated - nausea, vomiting, diarrhea, constipation. They were dose-dependent and mostly mild to moderate. Dose-dependent increases in heart rate were also observed.
  • From the tesamorelin arm (GHRH): Reported items include injection-site reactions, joint and limb complaints, fluid retention and occasional tingling. Glucose parameters stayed largely stable in the trials.

In the fixed blend both profiles add up. Because the reta share limits first when you dose up, GI complaints are the most likely reason you cannot go higher. No safety profile exists for this exact combination - there is correspondingly a lot of uncertainty in play.

Tolerability

Frequency in studies of the components

Share with the event in the phase 3 trials of the components. There are no data on the blend.

8 of 100 Placebo
14 of 100 Retatrutide, lowest study dose
21 of 100 Retatrutide, middle study dose
28 of 100 Retatrutide, highest study dose (12 mg)
Event PlaceboRetatrutide, lowest study doseRetatrutide, middle study doseRetatrutide, highest study dose (12 mg)
Nausea (Retatrutide, TRIUMPH-2)7 8%14%21%28%
Diarrhoea (Retatrutide, TRIUMPH-2)7 13%27%34%34%
Injection site reaction (tesamorelin)11 6%0%0%0%
Joint pain (tesamorelin)11 11%0%0%0%
Fluid retention in legs or arms (tesamorelin)11 2%0%0%0%

Rounded values. Retatrutide from the TRIUMPH-2 abstract (80 weeks), tesamorelin from the US prescribing information (first 26 weeks, both phase 3 trials). In the blend both profiles would add up.711

Practice

Plain-language framing: this blend is an experimental setup, not a mature combination product. Anyone looking for the solid research on Retatrutide or Tesamorelin should look at the individual lexikon entries for the two originals - that is where the entire body of evidence sits.

  1. Reta and tesa have very different typical doses - a fixed 1:1 mix never hits both ideally at once.

  2. Dose reta-anchored (the potent share first), otherwise you risk a reta overdose while chasing more tesa.

  3. No human data on the combination also means: no statement on long-term safety of this exact mix.

A glass of water, a bowl of green vegetables, a bowl of berries and a white notebook on a bright kitchen counter

If you specifically want to push one of the two mechanisms, the individual injectable entries are the more honest and cleaner starting point. This blend stays experimental.

Storage

Store the unopened, freeze-dried vial cool and dark. Once mixed, it keeps for at least 4 to 6 months in the fridge (2 to 8 °C). Bacteriostatic water as the solvent inhibits microbial growth. Do not freeze, protect from heat and direct light.

Shelf life

How long it keeps

Undissolved (powder) Cool and dark

Keep the undissolved powder cool and away from light.

Dissolved (mixed) Fridge, 2 to 8 degrees, do not freeze

Keeps for at least 4 to 6 months. Bacteriostatic water as the solvent inhibits microbial growth.

  • Keep it dark
  • Dissolved: 2 to 8 degrees
  • Note the mixing date on the vial
Nine vials with white powder and blue caps in the door shelf of a bright fridge
Once dissolved into the fridge (2 to 8 degrees), stable there for at least 4 to 6 months, do not freeze. Symbolic image.

Related

Related compounds

Same receptors or blends with Reta + Tesamorelin Blend: all in the TPD lexicon.

Reta + Tesamorelin Blend
Retatrutide Component: triple agonist Tesamorelin Component: GHRH analogue Tesa + Ipa Blend Tesamorelin with ipamorelin Reta + Cagri Blend Retatrutide with cagrilintide Tirzepatide Dual agonist, GLP-1 and GIP CJC-1295 without DAC Also at the GHRH receptor

FAQ

Common questions about Reta + Tesamorelin Blend

Short answers, each backed by the sources below.

Is the Reta + Tesamorelin Blend approved or studied?

No. As of 26 October 2026 the registry ClinicalTrials.gov lists no trial with Retatrutide and tesamorelin together. Tesamorelin alone has been approved in the USA since 2010, Retatrutide is in phase 3 and not approved.131415

What is the catch with the fixed mix?

The two substances were studied on very different schedules: Retatrutide once a week, tesamorelin daily. In a 1:1 vial the ranges from both trial programmes cannot be matched at the same time. The entry therefore goes by the Retatrutide share.13

What do the Retatrutide trials show?

In phase 2 body weight fell by 24.2 percent after 48 weeks at the highest study dose, by 2.1 percent on placebo. In phase 3 (TRIUMPH-1) it was 25.0 versus 3.9 percent after 80 weeks. A meta-analysis with 878 participants confirmed clear effects on weight and metabolic values.162

What do the tesamorelin trials show?

In 806 patients with HIV and excess belly fat, visceral fat fell by 15.4 percent more than on placebo in 26 weeks, subcutaneous fat stayed nearly the same. IGF-1 rose, blood sugar stayed stable. Those who continued kept the effect to week 52.45

Which side effects were seen with the components?

Retatrutide: mainly nausea, diarrhoea and other gastrointestinal effects, depending on the dose, plus a slight rise in heart rate. Tesamorelin: injection site reactions, joint and muscle pain, fluid retention and tingling. There is no safety profile for the blend.7111

Which trials are still running?

Nine phase 3 trials of Retatrutide are running, the largest on heart and kidney events until 2029. The phase 3 trials of tesamorelin were completed years ago. No trial of the blend is listed in the registry.1213

Glossary

Terms explained briefly

Dotted words in the text open these explanations directly.

Agonist
A substance that binds to a receptor and activates it, like the body's own messenger. A triple agonist activates three different receptors.
GHRH
Growth hormone-releasing hormone: messenger from the brain that makes the pituitary release growth hormone.
GIP
Glucose-dependent insulinotropic polypeptide: a second gut hormone that boosts insulin release when blood sugar is high.
GLP-1
Glucagon-like peptide 1: gut hormone that releases insulin, slows gastric emptying and signals fullness in the brain.
Glucagon
Pancreatic hormone. It can raise blood sugar and increases fat breakdown and energy use in the liver.
IGF-1
Growth factor made mainly by the liver under growth hormone. It serves as a marker of the effect.
Lipodystrophy
Disturbed fat distribution, with HIV therapy often more fat in the belly and less on arms and legs.
Lyophilisate
Freeze-dried powder. Without water a peptide keeps much longer.
Meta-analysis
Combined analysis of several studies to get a more precise overall result.
Placebo
Dummy preparation without active substance. Comparing against it shows what is due to the substance itself.
Subcutaneous
Into the fat layer just under the skin.
Visceral fat
Fat inside the abdomen around the organs, as opposed to fat just under the skin.

Evidence

Sources

Show all 15 sourcesHide sources 10 Studies2 Trial registry3 Database checked 26 Oct 2026

Studies

  1. Retatrutide: phase 2 study in obesity

    Jastreboff et al., New England Journal of Medicine, 2023

    DOI 10.1056/NEJMoa2301972 PMID 37366315 NCT04881760
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  2. Retatrutide: meta-analysis of three trials with 878 participants

    Abdrabou Abouelmagd et al., Baylor University Medical Center Proceedings, 2025

    DOI 10.1080/08998280.2025.2456441 PMID 40291085
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  3. Tesamorelin: phase 3 trial on belly fat in HIV with extension

    Falutz et al., Journal of Acquired Immune Deficiency Syndromes, 2010

    DOI 10.1097/QAI.0b013e3181cbdaff PMID 20101189 NCT00608023
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  4. Tesamorelin: pooled analysis of both phase 3 trials

    Falutz et al., Journal of Clinical Endocrinology & Metabolism, 2010

    DOI 10.1210/jc.2010-0490 PMID 20554713
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  5. Tesamorelin: first phase 3 trial on belly fat in HIV

    Falutz et al., New England Journal of Medicine, 2007

    DOI 10.1056/NEJMoa072375 PMID 18057338 NCT00123253
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  6. Retatrutide: phase 3 trial TRIUMPH-1 in obesity

    Jastreboff et al., New England Journal of Medicine, 2026

    DOI 10.1056/NEJMoa2604169 PMID 42814954 NCT05929066
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  7. Retatrutide: phase 3 trial TRIUMPH-2 with type 2 diabetes

    Bellido et al., The Lancet, 2026

    DOI 10.1016/S0140-6736(26)01861-1 PMID 42810372 NCT05929079
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  8. Retatrutide: phase 2a substudy on liver fat (MASLD)

    Sanyal et al., Nature Medicine, 2024

    DOI 10.1038/s41591-024-03018-2 PMID 38858523
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  9. Retatrutide: phase 1b study with half-life

    Urva et al., The Lancet, 2022

    DOI 10.1016/S0140-6736(22)02033-5 PMID 36354040 NCT04143802
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  10. Retatrutide: discovery and pharmacology of the triple agonist

    Coskun et al., Cell Metabolism, 2022

    DOI 10.1016/j.cmet.2022.07.013 PMID 35985340
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed

Trial registry

  1. Trials of the components on ClinicalTrials.gov

    ClinicalTrials.gov, U.S. National Library of Medicine

    Checked 26 Oct 2026 via ClinicalTrials.gov API v2
  2. Search for Retatrutide and tesamorelin together (no trial)

    ClinicalTrials.gov, U.S. National Library of Medicine

    Checked 26 Oct 2026 via ClinicalTrials.gov API v2

Database

  1. Tesamorelin: US prescribing information (approval, side effects)

    DailyMed, U.S. National Library of Medicine

    Checked 26 Oct 2026 via DailyMed
  2. Retatrutide: mechanism and targets in ChEMBL

    ChEMBL, EMBL-EBI (CHEMBL5095485)

    Checked 26 Oct 2026 via ChEMBL
  3. Tesamorelin: approval and target in ChEMBL

    ChEMBL, EMBL-EBI (CHEMBL1237026)

    Checked 26 Oct 2026 via ChEMBL

In the shop

Reta + Tesamorelin Blend in the catalog

Sizes, prices and shipping times are on the product page.

To the product