For Research Purposes Only · Not For Human Consumption

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≥98% (HPLC-UV)
Lot LX-2501Summer Sale · 30% Off
Retatrutide 20mg vial
Third-party tested
CoA available
UK dispatched
CoA verified

Metabolic Research

Buy Retatrutide 20mg UK | Research Grade

Higher-dose triple-receptor GLP-1, GIP and glucagon agonist for extended research. Retatrutide (Reta) as lyophilised powder with batch-matched CoA.

£99.99

£142.84

In stock

Inc. VAT · Free UK shipping on this order

1

SSL encrypted · Same-day dispatch before 6pm · CoA on this lot

Order before 6pm tomorrow for same-day dispatch

Independently HPLC-tested. Lot-matched CoA available on request — quote your batch and order ID.

What ships with your order

  • 011 × Retatrutide 20mg — lyophilised, sealed glass vial
  • 02Signed CoA — batch LX-2501, HPLC-UV + mass-spec
  • 03Royal Mail Tracked 24 — same-day dispatch before 6pm, Mon–Fri
Research Compound

About Retatrutide

The 20mg presentation of Retatrutide (LY3437943), Eli Lilly's investigational triple agonist targeting the GLP-1, GIP and glucagon receptors simultaneously. Identical synthesis and pharmaceutical-grade lyophilised powder as the 10mg vial, at double the peptide payload — a lower cost-per-milligram option for research groups running extended in-vitro protocols, ≥98% HPLC verified with a full third-party Certificate of Analysis. Peptides UK supplies retatrutide strictly for in-vitro and preclinical laboratory research. This compound is not approved for human use and is not a licensed medicine.

Research areas

  • GLP-1/GIP/glucagon receptor signalling
  • Metabolic pathway modelling
  • Adipogenesis & lipid metabolism
  • In-vitro obesity models
Compound Profile

Retatrutide 20mg — mechanism, research applications & compound data

Retatrutide 20mg — also searched for as "Reta 20mg" — is the extended-supply presentation of Eli Lilly's investigational triple GLP-1/GIP/glucagon receptor agonist (LY3437943). Identical pharmaceutical-grade synthesis as the 10mg vial — ≥98% HPLC purity, full third-party Certificate of Analysis, same-day UK dispatch from Manchester — at a substantially lower per-milligram cost for laboratories running extended in-vitro protocols.

01

Retatrutide 20mg UK — our extended-dose vial

This page lists the Retatrutide 20mg vial specifically — double the peptide payload of our standard listing, for laboratories running longer in-vitro protocols. "Reta" is the shorthand name researchers commonly use for Retatrutide (LY3437943); if you're searching more generally for retatrutide, buy retatrutide UK, or retatrutide for sale UK, our Retatrutide 10mg vial is the standard listing you're looking for. Both vials are the same synthesis, ≥98% HPLC-verified and CoA-backed, dispatched same-day from Manchester.

02

Retatrutide 20mg: extended-protocol research vial

The 20mg presentation doubles the peptide payload per vial without changing any aspect of synthesis, purity standard or third-party verification. It is the recommended option for research groups conducting multi-week receptor pharmacology studies, dose–response titration series, or extended adipocyte and hepatocyte assays where consolidating lot handling reduces analytical noise and cost per data point.

03

How Retatrutide works — triple-agonist GLP-1/GIP/glucagon pharmacology

Retatrutide engages three metabolic G-protein-coupled receptors in parallel: GLP-1R (incretin/insulinotropic signalling and delayed gastric emptying), GIPR (adipocyte lipid storage modulation and insulin amplification), and GcgR (hepatic glucose output, lipolysis and energy expenditure). The fatty-acid acylation extends plasma half-life sufficiently for once-weekly dosing in clinical research designs. The molecule is the leading reference compound for triple-agonist incretin pharmacology research.

04

In-vitro research applications for the 20mg vial

Typical use cases include extended GPCR signalling cascades (cAMP, β-arrestin, ERK1/2), comparative pharmacology against tirzepatide and semaglutide, long-duration adipocyte differentiation and brown-adipose thermogenesis research, hepatic stellate and hepatocyte glucose-output models, and pharmacokinetic stability studies of fatty-acid-modified peptide analogues. The 20mg vial supports approximately twice the protocol duration of the 10mg vial under identical reconstitution concentrations.

05

Storage, reconstitution and stability

Store the lyophilised vial at -20°C in its sealed container, protected from light and moisture. Allow the vial to reach room temperature before opening. Reconstitute with bacteriostatic water (0.9% benzyl alcohol) — typically 2ml or 3ml per 20mg vial — adding solvent down the side of the vial without agitation. Refrigerate the reconstituted solution at 2–8°C and use within 28 days. Do not refreeze.

06

Third-party verified purity and lot traceability

Every Retatrutide 20mg vial dispatched ships with a signed PDF Certificate of Analysis from Janoshik Analytical or Aspen Bioanalytics covering HPLC-UV purity (≥98%), mass-spectrometry identity, residual solvents and visual inspection. The CoA on this page corresponds to the exact lot you will receive. Lot numbers on the vial and the CoA always match — no exceptions.

07

Why buy Retatrutide 20mg from Peptides UK

Peptides UK is a UK-stocked, UK-dispatched research peptide supplier — no overseas customs delays, no grey-market sourcing, no anonymous fulfilment. Same-day dispatch on orders before 6pm GMT, Royal Mail Tracked 24, insulated cold-chain packaging, and verified third-party CoAs on every batch. The 20mg presentation offers the lowest cost per milligram in the UK research market for verified ≥98% HPLC Retatrutide.

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References & further reading

Primary sources cited on this page

The 20mg presentation is the same active compound as the 10mg vial — LY3437943 (informally "Reta"), a 39-residue synthetic peptide triple agonist of the GCGR, GIP and GLP-1 receptors developed by Eli Lilly. It is investigational and unlicensed.

Peer-reviewed literature & regulatory records

  1. [1] Jastreboff et al., 'Triple–Hormone-Receptor Agonist Retatrutide for Obesity'
    New England Journal of Medicine, 2023;389:514-526
  2. [2] Rosenstock et al., Phase 2 in type 2 diabetes
    The Lancet, 2023;402:529-544
  3. [3] Coskun et al., discovery & proof of concept
    Cell Metabolism, 2022;34:1234-1247
  4. [4] TRIUMPH Phase 3 programme
    ClinicalTrials.gov
  5. [5] PubChem compound record (LY3437943)
    NCBI PubChem CID 156588324

Analytical & handling guides

Regulatory & compliance notice

This product is supplied strictly for in-vitro laboratory research. It is not a licensed medicine in the United Kingdom, is not approved by the Medicines and Healthcare products Regulatory Agency (MHRA) or the European Medicines Agency for human or veterinary use, and is not intended to diagnose, treat, cure or prevent any disease. Nothing on this page constitutes medical advice.

External links point to primary literature or regulatory records and open in a new tab. Citations are provided so the reader can independently verify every factual claim made on this page. Last reviewed 22 July 2026.

Certificate of Analysis

Retatrutide 20mg

Independent lab
Janoshik Analytical
Batch number
LX-2501
Method
HPLC-UV + MS
Result
≥98% (HPLC-UV)
Download CoA (PDF) — Retatrutide 20mgView full Certificate of Analysis for batch LX-2501

The CoA you download is the exact certificate produced for this lot — no edits.

Storage & handling

Keep it stable, keep it sterile

  • Storage: Store lyophilised powder at -20°C in a sealed vial. Protect from light and moisture. Allow the vial to reach room temperature before opening to prevent condensation entering the vial. Do not store in a frost-free freezer.
  • Reconstitution: Reconstitute using bacteriostatic water (0.9% benzyl alcohol). Add solvent slowly down the side of the vial — do not shake. Allow to dissolve gently at room temperature.
  • Reconstituted stability: Once reconstituted, store at 2–8°C (refrigerated). Use within 28 days. Do not refreeze after reconstitution.
  • Shipping: All vials are dispatched in insulated mailers with ice packs to maintain cold chain during Royal Mail Tracked 24 transit.
+ Add Bacteriostatic Water (£4.99) →
FAQ

Retatrutide 20mg — common questions

Related

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    Retatrutide 10mg vial

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    Triple-receptor GLP-1, GIP and glucagon agonist. Retatrutide — often shortened to 'Reta' — is the most advanced metabolic research peptide, supplied as lyophilised powder with batch-matched CoA.

    ≥98% HPLCIn Stock

    £59.99£85.70

  • Essential
    Bacteriostatic Water 3ml vial

    Accessories / Reconstitution

    Bacteriostatic Water · 3ml

    0.9% benzyl alcohol bacteriostatic water for peptide reconstitution. Pharmaceutical-grade, sterile-filtered 3ml vial.

    ≥98% HPLCIn Stock

    £4.99

Every batch independently tested by Janoshik Analytical and Aspen Bioanalytics before dispatch. Signed certificates available on every product page.

Third-party HPLC-UV testing Lot-matched CoA on every order Batch-traceable from dispatch

Legal notice

This product is sold strictly for in-vitro laboratory research purposes only. It is not approved for human or veterinary use, is not a drug, food, or cosmetic, and should not be misused as such. Peptides UK accepts no liability for misuse. By purchasing you confirm you are a qualified researcher aged 18 or over.

Retatrutide 20mg

£99.99£142.84