Photograph · Pen and cartonLot AV-R3T-2609-A
Retatrutide (R3T)
Peptide pen · 40 mg / 3 mL
VAT included · 1 pen · 40 mg / 3 mL
Sold for research use only. Not a medicine and not authorised for human consumption. Purchasers must be 18+ and confirm intended use at checkout.
Investigational — not authorised anywhere.
- Ships chilled · same-day dispatch before 2 pm
- Free UK shipping over £300
About
What this is
R3T is an investigational peptide designed to activate GIP, GLP-1 and glucagon receptors. It is being studied in controlled clinical programmes for weight, appetite and wider metabolic outcomes. Supplied by the manufacturer as a pre-filled 40 mg / 3 mL dose-dial pen for research use — no reconstitution, no vials, no drawing up. Our evidence record is linked below and graded on the same scale as every compound on this site.
- 01Pre-filled pen — no reconstitution
- 02Identity confirmed by LC-MS per lot
- 03Purity ≥ 99% by HPLC
- 04Certificate published against the lot number
Specification
What's in the pen
Device
How the pen works
- 01
Attach a pen needle
Take the cap off, wipe the septum with an alcohol swab and screw a compatible pen needle on until it seats. Use a fresh needle every time and never share a pen.
- 02
Prime
Dial a small test amount, hold the pen needle-up and press the button until a drop appears at the tip. This clears air from the needle and confirms the pen delivers.
- 03
Dial
Turn the dial to the volume you intend to deliver; the window shows the setting in the pen's increments. The dial sets a volume of solution — nothing more.
- 04
Inject
Insert as the pen-needle instructions describe, press the button fully and hold for ten seconds before withdrawing. Remove and bin the needle in a sharps container, recap and refrigerate.
Dosing is not provided; see the research information in the evidence record. These steps describe how the device operates, not how or whether to use its contents.
Certificate of analysis
Lot AV-R3T-2609-A
Independent test of a sample from lot AV-R3T-2609-A of Retatrutide (R3T). Testing confirms what is in the pen and how pure it is; it does not speak to safety or effect in people. How we test
Evidence record · reviewed 1 Sept 2026
What the research says about Retatrutide
Investigational triple agonist with the largest trial weight loss reported so far.
- Overall evidence
- Moderate
- Human evidence
- Late-stage clinical trials
- Regulatory · jurisdictions on record
- Investigational
- Investigational · United Kingdom, United States, European Union, Australia and Canada
- United Kingdom · Not authorised; in phase 3 trials (TRIUMPH programme). · reviewed 1 Sept 2026
- Anti-doping · WADA
- Not on the Prohibited List
Fit
Who this is for
Weight and metabolic goals where the investigational triple-receptor agonist is the interest — phase 3 data only, not authorised anywhere.
- Significant weight to lose and interest in the newest incretin research
- Metabolic health alongside weight
- Understanding an investigational compound before it is licensed
Check your fit
The Peptide Checkup maps your goal and history against the evidence for this pen and tells you if it is a poor fit — even after you have bought it.
Check your fit · 7 minutesAlso in the range · by shared goal, then bestsellers
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