Description
Strictly for laboratory research. Not for human consumption, self-administration, medical, veterinary, diagnostic or therapeutic use.
PRODUCT OVERVIEW
Retatrutide 40mg Pen: Format and Specification
Retatrutide (LY3437943) 40mg is a synthetic 39-amino-acid triple receptor agonist supplied to qualified researchers for controlled laboratory and analytical work. Unlike dual GIP/GLP-1 agonists, it adds glucagon receptor activity to the GIP and GLP-1 arms, giving a broader receptor profile than any compound it is compared against in the current literature. It is under Phase 3 investigation by Eli Lilly and holds no marketing authorisation anywhere in the world.
This is a prepared 40mg pen supplied lyophilised and sealed across four 10mg doses. No reconstitution is required on arrival, and nothing needs to be mixed before use. The pen format fixes the concentration per actuation, which removes the variance that manual reconstitution introduces. Where a protocol requires a concentration the pen does not offer, a lyophilised vial is the correct alternative. Each pen carries a batch reference that links to the analytical documentation for that specific lot.
Purity is assessed by independent HPLC and identity is confirmed separately by mass spectrometry. These answer different questions: HPLC reports what proportion of the sample is the target molecule, mass spectrometry confirms the molecule present is actually retatrutide and not a structural analogue. A purity figure without a matching identity result is only half the evidence, so both appear on the Certificate of Analysis, along with the issuing laboratory, method, units and document date.
Retatrutide is not a licensed medicine. It cannot be prescribed and is not available from any pharmacy in the UK, the EU or the US. Supplied as a research reagent only, to buyers aged 21 or over. Not a controlled drug, and not for human or veterinary consumption, injection, diagnosis, treatment or self-administration. Store refrigerated at 2-8 degrees C, protected from light, do not freeze.
- 40mg lyophilised pen, four 10mg doses – no reconstitution
- Triple agonist: GIP + GLP-1 + glucagon (LY3437943)
- HPLC purity and separate mass-spec identity confirmation
- Batch COA published on this page, downloadable before ordering
- Strictly research use only, buyers aged 21 or over
Retatrutide 40mg Pen Price and UK Delivery
Where to Buy Retatrutide 40mg Pen in the UK
You can buy Retatrutide 40mg Pen direct from UK stock, dispatched the same working day when ordered before 9am. Where to buy is a documentation question as much as a stock question: confirm the batch certificate, the identity result and the stated storage condition before you order. Price for this pen is shown in the purchase panel above, including the tiered multi-pen discounts.
Current pricing, pack sizes and UK delivery options are shown in the purchase panel above. Free UK delivery is Royal Mail Tracked 48; Tracked 24 and international options are quoted at checkout.
BATCH DOCUMENTATION
Certificate of Analysis available.
Review the available COA and match the product name, strength and batch reference. The document — not a marketing headline — is the source for the issuing laboratory, analytical methods, units, reported results and limitations.
TECHNICAL REFERENCE
Retatrutide 40mg Pen vs Vial: What Arrives and What Changes
Chemical identifiers are provided for research reference. Product release information and batch-specific analytical results should be taken from the available COA.
- Product name
- Retatrutide 40mg Pen Research Peptide
- Alternative names
- Retatrutide, LY3437943
- Quantity
- 40mg
- Peptide length
- Single-chain peptide
- Molecular formula
- C221H342N46O68
- Molecular weight
- Approximately 4731 g/mol
- CAS Registry Number
- 2381089-83-2
- PubChem identifier
- CID 16137828
- Product format
- Lyophilised research material (pen)
- Analytical specification
- Refer to the available batch-specific Certificate of Analysis
- Intended use
- Laboratory research and analytical applications only
- Storage
- Store refrigerated at 2-8°C, protected from light, do not freeze
The sequence, formula, molecular weight, CAS number and PubChem identifier are provided as chemical reference information. The batch COA and product label take priority for the exact material supplied.
Literature context only. References do not establish that this product has proven human efficacy, clinical benefit, safety, approval or equivalence with any authorised formulation. Assess every source, model, population and limitation independently.
Batch Purity and Analytical Testing for Retatrutide 40mg Pen
Retatrutide 40mg Pen has been examined in published pharmacology and clinical literature using defined formulations and populations. These sources provide scientific and regulatory context only; they do not make this laboratory product an approved medicine or establish equivalence with a branded formulation.
Triple incretin receptor signalling
Retatrutide is described as a single-chain peptide investigated for simultaneous GIP, GLP-1 and glucagon receptor activity in experimental models. Each of the three receptors is associated with distinct downstream signalling cascades, and published work examines how concurrent activity at all three is characterised in laboratory systems.
Metabolic and body-weight research
Published non-clinical and clinical literature has examined incretin receptor agonists in relation to metabolic markers and body-weight regulation. Retatrutide appears in this literature as a comparator and as an investigational molecule in its own right. Results reported for other formulations or research materials do not establish equivalence, approval, clinical safety or efficacy for this product.
Comparative incretin literature
Because Retatrutide acts on three receptors rather than two, it is frequently compared against dual agonists in metabolic research. Comparative studies typically examine receptor-selectivity profiles and the analytical methods used to distinguish single, dual and triple agonists.
Analytical and identity research
Research use of any peptide depends on confirming identity and purity. Published chemical reference data covers sequence, molecular formula, molecular weight and identifiers, while batch-specific purity is established by the analytical methods stated in the issuer's Certificate of Analysis.
Research library
Every published guide, comparison and reference for Retatrutide Pen on United Peptides.
Research guideRetatrutide Research Guide: Triple Agonist MechanismRetatrutide isn’t a bigger semaglutide. It is a different class of molecule altogether – the first unimolecular agent characterised in the…
ComparisonRetatrutide vs Tirzepatide: 3 Critical Mechanism DifferencesRetatrutide vs Tirzepatide comes down to receptor count. Both are engineered incretin mimetics studied for metabolic signalling. The difference…
Strength guideRetatrutide 20mg vs 40mg: 4 Critical Factors That Decide ItRetatrutide 20mg vs 40mg is a quantity decision, not a quality one. Both are the same molecule at different fill quantities. There is no…
HandlingRetatrutide Pens vs Vials: 5 Critical Practical DifferencesPens vs Vials: What Actually Changes Retatrutide pens vs vials is not a question of quality. Research peptides are supplied in two physical…
Buyer guideWhere to Buy Retatrutide UK: 5 Proven Checks Before You OrderLooking to source retatrutide in the UK? Understand purity grading, batch documentation and what to check before buying research-grade retatrutide.
PricingCheapest Retatrutide UK: 5 Proven Ways to Compare PricesCheapest Retatrutide UK is rarely the lowest number on the page. The lowest headline figure is seldom the cheapest option in practice. Price per…Selected scientific sources
PubChem compound record — Sequence, molecular formula, molecular weight, CAS number, synonyms and compound identifiers.
Published incretin research — Peer-reviewed studies indexed on PubMed examining the GIP, GLP-1 and glucagon receptor pathways.
Regulatory literature — Published guidance and literature on the research and analytical use of incretin receptor agonists.
Analytical method references — General references on HPLC and mass-spectrometry techniques used to assess peptide identity and purity in laboratory settings.
QUALITY DOCUMENTATION
Certificate of Analysis for Retatrutide 40mg Pen
United Peptides provides Certificate of Analysis information for this research product. Always match the product, strength and batch reference before using a report in a procurement or laboratory decision.
How to review the document
- Identify the batch — Match the product name, strength, lot or batch reference and document date.
- Review the methods — Read the exact analytical techniques stated in the report; do not assume HPLC, mass spectrometry or another method unless it is listed.
- Interpret the results — Check units, calculation basis, acceptance criteria, qualifiers and limitations together.
- Preserve traceability — Keep the COA connected to receiving, storage and experimental records for the same batch.
Verified Researcher –
Packaging arrived intact and the pen was clearly labelled with the batch reference. The certificate for this lot matched what was listed on the product page, which is what I needed for my records. Delivery took two working days.
Emma G –
Great service and very quick delivery.
Alex P –
Very good service. Received my reta pen within 24 hours! Thanks