Cagrilintide + Retatrutide
Cagrilintide with retatrutide
Also called cagri reta, cagrilintide retatrutide stack, amylin triple agonist stack, CagriReta
An unapproved compound paired with an unapproved compound. No trial, no label, no precedent.
Combination evidence: Insufficient / conflicting
Where every number on this page comes from
Each quantity carries one of these five labels. They are not interchangeable, and the difference between the first and the last is the difference between a regulated finding and a rumour with a number attached.
- FDA labelling
- This figure appears in FDA-approved product labelling for an approved indication. It is the strongest warrant on this site.
- Published study arm
- This figure is the quantity administered in a named arm of the linked study. It describes what was studied, not what is advised.
- Clinical guideline
- This figure appears in published clinical or professional guidance.
- Manufacturer protocol
- This figure comes from a manufacturer or investigator document rather than from peer-reviewed literature.
- Community practice — no trial
- No clinical trial has tested this figure. It reflects what is commonly reported in practice and carries no evidentiary weight. It is shown because it is what circulates, and because showing it with this label is more useful than pretending it does not exist.
The figure most often reported for each compound. Where a compound has no separately sourced figure at this level, its most commonly reported figure is used instead, and the citation beneath it says so.
Duration
16 weeks
2 phases
Administrations
32
about 2/week at peak
Vials required
10
2 compounds
Cost at this plan
$1,042.95
Peptira, list price
Phase by phase
Weeks 1–12 · 12 weeks
Escalation
Retatrutide's own phase 2 escalated every four weeks for up to twelve weeks. Cagrilintide's escalated every two. Combining them means choosing one cadence with nothing to justify the choice.
Retatrutide
Once weekly, Sunday · Subcutaneous
Lowest sourced, per dose
1 mgPublished study arm
Retatrutide 1 mg · Phase 2, lowest arm, no escalation · in the study register
Most commonly reported, per dose
4 mgPublished study arm
Retatrutide 4 mg · Phase 2, 4 mg maintenance arm · in the study register
Highest sourced, per dose
8 mgPublished study arm
Retatrutide 8 mg · Phase 2, 8 mg maintenance arm · in the study register
Prepared at 10 mg in 2 mL
Every quantity above is one administration. At once weekly, sunday, that is 4.00 mg per week.
| Concentration | 5.00 mg/mL | Draw volume | 0.800 mL |
| Pull to (U-100) | 80.0 units | Doses per vial | 2 |
| This phase | 12 administrations | Vials, this phase | 6 |
Why it is here
Triple agonist at the GIP, GLP-1 and glucagon receptors. The largest weight changes reported in any published obesity trial to date.
What is not known
One phase 2 trial, 338 people, 48 weeks. No phase 3 result is published, and no regulator has reviewed it.
Cagrilintide
Once weekly, Sunday · Subcutaneous
Lowest sourced, per dose
300 mcgPublished study arm
Cagrilintide 0.3 mg · Phase 2 dose-finding, lowest arm · in the study register
Most commonly reported, per dose
1.2 mgPublished study arm
Cagrilintide 1.2 mg · Phase 2 dose-finding, mid arm · in the study register
Highest sourced, per dose
2.4 mgPublished study arm
Cagrilintide 2.4 mg · Phase 2 dose-finding, the amount taken into phase 3 · in the study register
Prepared at 5 mg in 2 mL
Every quantity above is one administration. At once weekly, sunday, that is 1.20 mg per week.
| Concentration | 2.50 mg/mL | Draw volume | 0.480 mL |
| Pull to (U-100) | 48.0 units | Doses per vial | 4 |
| This phase | 12 administrations | Vials, this phase | 3 |
Why it is here
Amylin analogue, added on the argument that satiety signalling is a separate pathway from the incretin receptors.
What is not known
That argument is mechanistic. It has been tested with semaglutide and with nothing else.
Weeks 13–16 · 4 weeks
Hold
Four weeks at the held amounts.
Retatrutide
Once weekly, Sunday · Subcutaneous
Most commonly reported, per dose
8 mgPublished study arm
Retatrutide 8 mg · Phase 2, 8 mg maintenance arm · in the study register
Highest sourced, per dose
12 mgPublished study arm
Retatrutide 12 mg · Phase 2, highest arm · in the study register
Prepared at 20 mg in 2 mL
Every quantity above is one administration. At once weekly, sunday, that is 8.00 mg per week.
| Concentration | 10.00 mg/mL | Draw volume | 0.800 mL |
| Pull to (U-100) | 80.0 units | Doses per vial | 2 |
| This phase | 4 administrations | Vials, this phase | 2 |
Why it is here
The arms that produced the largest reported weight change at 48 weeks.
What is not known
The 12 mg arm's advantage over 8 mg at week 24 was within noise. The separation appeared later, in a secondary endpoint.
Cagrilintide
Once weekly, Sunday · Subcutaneous
Most commonly reported, per dose
2.4 mgPublished study arm
Cagrilintide 2.4 mg · Phase 2 dose-finding, the amount taken into phase 3 · in the study register
Prepared at 5 mg in 2 mL
Every quantity above is one administration. At once weekly, sunday, that is 2.40 mg per week.
| Concentration | 2.50 mg/mL | Draw volume | 0.960 mL |
| Pull to (U-100) | 96.0 units | Doses per vial | 2 |
| This phase | 4 administrations | Vials, this phase | 2 |
Why it is here
The amount the phase 3 programme selected.
What is not known
Selected for a semaglutide pairing, not this one.
What you would need to buy
Vial counts are computed by simulating consumption, not by dividing total milligrams. Those two disagree whenever a vial cannot be finished, which is most of the time, and dividing under-buys.
| Compound | Vial | Administrations | Total material | Vials |
|---|---|---|---|---|
| RetatrutideEscalation · Hold | 20 mg | 16 | 80.00 mg | 5 |
| CagrilintideEscalation · Hold | 5 mg | 16 | 24.00 mg | 5 |
| Total | 32 | 10 | ||
What it would cost
List prices from each vendor’s own product pages, with the date each figure was read. Quantity tiers are applied where a vendor publishes them.
Loti Labs
Prices as of 2026-08-24
$1,859.88
$16.61/day · $505.49/month
| RetatrutideReta 20mg (GLP-3) · 20 mg$14.25/mg listed · $17.81/mg after what expires unused | 5 × $284.99 | $1,424.95 |
| CagrilintideCagrilintide 5mg · 5 mg$16.20/mg listed · $16.87/mg after what expires unused | 5 × $80.99 | $404.95 |
| Bacteriostatic water10ML Reconstitution Solution · 10 mLThis plan uses 20.0 mL across every reconstitution. | 2 × $14.99 | $29.98 |
| Syringes32 administrations, so 32 syringes. None of the vendors priced on this site sells syringes, alcohol pads or a sharps container. They are ordinary pharmacy items in most places and restricted in some. The count below is what the plan requires; where to obtain them is outside what this site can tell you. | 32 × — | Not sold here |
| Total, compounds and water | $1,859.88 | |
Above this vendor's published $99 free-shipping threshold.
We earn nothing from this link. Loti Labs has no affiliate programme.
Pure Health Peptides
Prices as of 2026-08-24
$286.99
$2.56/day · $78.00/month
| RetatrutidePure Health Peptides's largest listing for this compound is 5 mg, and this plan administers up to 8 mg at once. One vial cannot deliver a single administration. Drawing each dose from two vials is possible, but it changes the syringe pull and doubles the reconstitution, so it is a different plan and is not priced here. | — | — |
| CagrilintideGLP-1 (C) · 10 mg$6.90/mg listed · $11.50/mg after what expires unusedPriced at the 10 mg size rather than the 5 mg this plan assumes, because across the sizes this vendor stocks it works out cheapest for the whole course. Vial count re-simulated at that strength. | 4 × $69.00 | $276.00 |
| Bacteriostatic waterBacteriostatic Water · 10 mLThis plan uses 8.0 mL across every reconstitution. 2.0 mL is left over, because bottles do not divide.The only size this vendor sells. Stock was reported as one unit remaining when read. | 1 × $10.99 | $10.99 |
| Syringes32 administrations, so 32 syringes. None of the vendors priced on this site sells syringes, alcohol pads or a sharps container. They are ordinary pharmacy items in most places and restricted in some. The count below is what the plan requires; where to obtain them is outside what this site can tell you. | 32 × — | Not sold here |
| Total, compounds and water | $286.99 | |
Above this vendor's published $175 free-shipping threshold.
This total is not comparable. Pure Health Peptides cannot supply Retatrutide, so the figure above covers a smaller basket than the other columns.
We earn nothing from this link. No affiliate programme was found for this vendor.
Peptira
Prices as of 2026-08-25
$1,072.95
$9.58/day · $291.61/month
| RetatrutideRETA-3 | 20MG · 20 mg$5.91/mg listed · $7.38/mg after what expires unusedIdentity inferred. This vendor sells it as “RETA-3 | 20MG” and does not write the compound name anywhere on the page. The mapping is ours, not theirs. | 5 × $118.15 | $590.75 |
| CagrilintideCAG-4 | 10MG · 10 mg$11.30/mg listed · $18.84/mg after what expires unusedIdentity inferred. This vendor sells it as “CAG-4 | 10MG” and does not write the compound name anywhere on the page. The mapping is ours, not theirs.Priced at the 10 mg size rather than the 5 mg this plan assumes, because across the sizes this vendor stocks it works out cheapest for the whole course. Vial count re-simulated at that strength. | 4 × $113.05 | $452.20 |
| Bacteriostatic waterBAC Water 10ML · 10 mLThis plan uses 18.0 mL across every reconstitution. 2.0 mL is left over, because bottles do not divide. | 2 × $15.00 | $30.00 |
| Syringes32 administrations, so 32 syringes. None of the vendors priced on this site sells syringes, alcohol pads or a sharps container. They are ordinary pharmacy items in most places and restricted in some. The count below is what the plan requires; where to obtain them is outside what this site can tell you. | 32 × — | Not sold here |
| Total, compounds and water | $1,072.95 | |
Above this vendor's published $250 free-shipping threshold.
Peptira runs an affiliate programme. This site has not applied to it, so no commission is earned on this link today.
List price is not the price anyone pays
What usually goes wrong
Ranked by how often it happens rather than by how serious it sounds.
Treating retatrutide's phase 2 numbers as settled
A single phase 2 trial is where drugs look their best. Effect sizes routinely shrink between phase 2 and phase 3, and this one has not made that transition in public.
Adding an amylin analogue to the strongest incretin available
The mechanistic argument for cagrilintide was built around adding to a GLP-1 agonist. Retatrutide already hits three receptors. What an amylin analogue adds on top of that is not established by anything.
Assuming sixteen weeks is a fair test
Retatrutide's own trial ran 48 weeks and its arms did not separate cleanly until well past week 24. Sixteen weeks would not have detected its main result.
What is worth measuring
Markers that would actually tell you something, and what each one tells you. Nothing here is a requirement, and none of it substitutes for a clinician who knows your history.
| Marker | When | What it tells you |
|---|---|---|
| Weight and waist | Weekly, same conditions | The measured endpoint in the underlying trial. |
| Resting heart rate | Baseline and periodically | Heart-rate increase was reported in the retatrutide phase 2. |
| Fasting glucose | Baseline and periodically | Glucagon receptor agonism has glucose effects the other classes do not. |
Populations this was not studied in
An absence of evidence in a group is not evidence of safety in that group. These are listed because the gap itself is the finding.
- Anyone — no human trial of this combination exists
- Anyone at all for retatrutide outside a clinical trial; it is not approved in any jurisdiction
- Pregnancy and breastfeeding
- Anyone under 18
Related protocols
Semaglutide
The 16-week step-up written into the approved label, with the arithmetic done for each step.
Tirzepatide
Labelled 2.5 mg steps to a 5, 10, or 15 mg maintenance, with 176-week follow-up behind it.
Retatrutide
What the published phase 2 arms actually administered. Not approved, and not a label.
Protocol last reviewed 2026-08-25. Every quantity on this page carries its own source. If you find one that does not, that is a bug and the build should have caught it.