Representative packaging image · verify the ordered lot
Decision summary
Key benefits
Research value: a single defined peptide enables study of coordinated GIPR, GLP-1R and GCGR agonism, receptor bias, metabolic signaling, analytical characterization and comparison with single- or dual-receptor agonists
Published clinical outcomes describe Lilly's investigational finished product and do not establish clinical performance, interchangeability or suitability of an RUO lot.
Published research context is presented for literature orientation only. It is not a dosing, treatment or human-use instruction.
Qualification data
Specifications to confirm against the released lot
CAS
2381089-83-2
Formula
C221H342N46O68
Molecular weight
4731.3 g/mol
Appearance
White lyophilized powder
Purity
≥ 99.0% · target, verify batch COA
Storage
Use the released-lot COA and stability statement for the supplied form. Define temperature, moisture and light protection, container closure, freeze-thaw allowance and solution matrix before use; do not infer solution stability from another vendor or a clinical finished product.
Identity, purity and content are separate release questions.
Identity
Confirm the stated molecule and supplied form. Start with the matching batch COA; request sequence-level evidence only when the buyer's written procedure requires it and availability or a separate scope has been agreed.
Purity
Review RP-HPLC method conditions, wavelength, integration and related-peak handling. A percentage without the method is not enough.
Content
Net peptide content is not the same as gross lyophilized powder weight. Ask which assay supports the stated amount and whether water/counter-ion is addressed.
Stability
Follow the storage condition stated on the batch COA or label from receipt onward.
Research context
What researchers study about Retatrutide
Retatrutide (LY3437943) is Lilly's investigational 39-residue, lipidated peptide agonist of the GIP, GLP-1 and glucagon receptors. Peer-reviewed evidence includes Phase 1 and Phase 2 studies and the 2026 Phase 3 TRANSCEND-T2D-1 trial. Lilly reported TRIUMPH-1 topline results on May 21, 2026 and additional nested-substudy data at the June 2026 ADA meeting; those sponsor-reported results should remain distinct from full peer-reviewed publication. As of July 2026, FDA states that retatrutide is not a component of an approved drug, has not been found safe and effective for any condition and cannot be used in compounding under U.S. federal law. The material described here is an analytical/research reagent, not Lilly's clinical product or a finished dosage form.
Evidence contexts include receptor pharmacology, metabolic signaling, obesity, type 2 diabetes, body composition and liver-fat endpoints
The 2023 Phase 2 obesity and diabetes trials, 2024 MASLD substudy, 2025 body-composition substudy and 2026 TRANSCEND-T2D-1 Phase 3 paper are peer reviewed
TRIUMPH-1 obesity, OSA and knee-OA figures currently cited in this record are sponsor-reported topline or conference results pending full peer-reviewed publication
These studies concern Lilly's investigational clinical product and do not create an approved indication or validate this RUO material for human use.
Mechanism context
The question the literature is testing
Retatrutide is an agonist at GIPR, GLP-1R and GCGR. The discovery paper reports comparatively greater GIPR potency with balanced GLP-1R and GCGR activity in the tested systems. Incretin-receptor signaling affects insulin secretion, food intake and metabolic control, while GCGR engagement can influence hepatic substrate handling and energy expenditure. Receptor activity supports mechanistic hypotheses but does not by itself prove a clinical outcome or lot-specific biological potency.
Dose / exposure contextProtocol-specific; verify the cited primary source
Routes and exposure contexts summarize cited studies or approved finished-product labels. They are not instructions for administering this RUO material; no customer dose is provided.
Evidence boundaries
Compatibility, limitations and decision context
Retatrutide remains unapproved
Peer-reviewed and sponsor-reported trials describe gastrointestinal adverse events and other safety observations for Lilly's investigational finished product, but do not establish safety of an independently supplied RUO lot
FDA states that retatrutide has not been found safe and effective for any condition and cannot be used in compounding under U.S. federal law
Handle as a research chemical under an institutionally approved risk assessment; this catalog entry provides no human-use guidance.
Interactions reported in the literature
No combination-use guidance is provided for this RUO material
Clinical trial exclusion criteria and concomitant-medication management belong to the registered protocols and investigator oversight; they must not be rewritten as self-directed interaction advice.
Literature context is not a supplier release result or human-use instruction. Follow your institution's approved laboratory risk assessment.
Batch documentation
Retatrutide batch COAs
Laboratory: Manufacturer's QC laboratoryTests: HPLC purity · MS identity · endotoxin · fill amount
5 mg
10 mg
15 mg
20 mg
30 mg
40 mg
50 mg
60 mg
Previews are blurred on purpose so the documents cannot be reused; third-party reports show their first page only. Sales sends the clear full version for the product and strength you ask about.
Published COAs show recent representative batches and may not be the newest. For a quote or shipment, sales confirms the lot and sends its COA.
Third-party reports, added progressively
Previews of the first page of third-party reports are on our Quality page and on the matching product pages; sales sends the full report on request. You can also send any vial from your order to an independent laboratory of your choice. Unless agreed otherwise in writing, the buyer pays for optional testing.
Help reviewing your COA
Need help reading a batch COA or third-party report? Sales can explain the test items, specifications and how the results relate to the lot under discussion.
On every batch COA: HPLC purity · MS identity · endotoxin · fill amount · Verify LyoPep
Third-party reports for Retatrutide
Reports from Qorix (tjqxgd.com), a third-party analytical laboratory in Tianjin, China: HPLC purity and MS identity of the sample tested.
Laboratory: Third-party laboratoryTests: HPLC purity · MS identity
50 mg
Previews are blurred on purpose so the documents cannot be reused; third-party reports show their first page only. Sales sends the clear full version for the product and strength you ask about.
Reports shared by other customers
Laboratory: Independent laboratory, commissioned by a customerTests: Content per vial · HPLC purity
20 mg
60 mg
Previews are blurred on purpose so the documents cannot be reused; third-party reports show their first page only. Sales sends the clear full version for the product and strength you ask about.
Ask for the current packet, not a generic certificate
Require complete modified-sequence identity, high-resolution intact mass, LC-MS/MS or another orthogonal sequence method, peptide-content assay, chromatographic purity with impurity assignment, counterion identity, water, residual solvents and aggregate assessment
Define endotoxin or bioburden only when the experimental model requires it
Appearance and HPLC area purity alone do not establish content, identity or clinical equivalence.
Batch COA for the released lotHPLC purity with method contextMS identity resultEndotoxin resultFill amount (measured content per vial)SDS and handling statement
Available fills
Quote the fill and pack configuration you need
Reference SKUFillBase pack
RT22 mg10 vials
RT55 mg10 vials
RT1010 mg10 vials
RT1212 mg10 vials
RT1515 mg10 vials
RT1616 mg10 vials
RT2020 mg10 vials
RT2424 mg10 vials
RT3030 mg10 vials
RT4040 mg10 vials
RT5050 mg10 vials
RT6060 mg10 vials
Other format
Also available as a nasal spray (US stock)
10 mL nasal spray bottle
Besides lyophilized vials, Retatrutide is also supplied as a nasal spray solution, shipped from our US stock.
Retatrutide is also supplied in capsule bottles, held in our US stock and shipped within the US. Ask our sales team for a quote. For research use only.
Strength
500 mcg per capsule
Ships from
Our US stock
Handling
Plan storage before the parcel arrives
Use the released-lot COA and stability statement for the supplied form. Define temperature, moisture and light protection, container closure, freeze-thaw allowance and solution matrix before use; do not infer solution stability from another vendor or a clinical finished product.
State the destination and timing so receipt can be planned, then move the material into its stated storage condition on arrival.
Buyer FAQ
Terms to settle before the purchase order
Can a buyer arrange third-party testing?+
Yes. You can send any vial from your order to an independent laboratory of your choice. If you want the laboratory, specification, sampling, method and acceptance rule agreed with us before testing, sales confirms them in writing. Unless otherwise agreed in writing, the buyer pays the cost of this optional testing.
What if my own lab test shows the product is out of specification?+
Send any vial from your order to an independent laboratory of your choice. If the report shows the product does not meet the specification on its COA — purity below the stated minimum, or an identity that does not match — share the report with our sales team and we refund that product in full.
Does HPLC purity prove peptide content?+
No. Chromatographic purity describes the relative peak profile under a stated method. Identity, water, counter-ion, residual solvents and assay/content may require separate methods.
How should material be stored after delivery?+
Move it into the storage condition stated on the batch COA or label as soon as it arrives, and record the package condition on receipt.
How are payment terms handled?+
Available methods and milestones depend on order value, destination and project type. The pro forma invoice should state currency, bank details, fees, payment milestones and the release condition.
Why must the testing laboratory understand peptide chemistry?+
Free-base and salt forms, hydrophilic and hydrophobic sequences, aggregation and adsorption can change sample preparation and method suitability. Use a laboratory experienced with the molecule class.
These are buyer-qualification references, not claims that this RUO material is regulated, certified or released under those frameworks. Applicability depends on the buyer's workflow and jurisdiction.
Selected sources
Literature behind the research context
Key primary sources: Coskun et al., Cell Metabolism 2022 (PMID 35985340); Jastreboff et al., NEJM 2023 (PMID 37366315); Rosenstock et al., Lancet 2023 (PMID 37385280); Sanyal et al., Nature Medicine 2024 (PMID 38858523); Giblin et al., Diabetes, Obesity and Metabolism 2026 (PMID 41090431); Bajaj et al., Lancet 2026 (PMID 42250575); ClinicalTrials.gov NCT05929066 and NCT06383390; PubChem CID 171390338; FDA's current unapproved-GLP-1 notice; and Lilly's official May and June 2026 TRIUMPH-1 disclosures. Peer-reviewed publications, registry records and sponsor-reported topline results are labelled separately in the literature section.
01
LY3437943, a novel triple glucagon, GIP, and GLP-1 receptor agonist for glycemic control and weight loss: From discovery to clinical proof of concept
Cell Metabolism · 2022 · peer-reviewed original research (preclinical + first-in-human phase 1)
Retatrutide, a GIP, GLP-1 and glucagon receptor agonist, for people with type 2 diabetes: a randomised, double-blind, placebo and active-controlled, parallel-group, phase 2 trial conducted in the USA
The Lancet · 2023 · peer-reviewed original research (randomized, double-blind, placebo- and active-controlled phase 2 trial)
Effects of retatrutide on body composition in people with type 2 diabetes: a substudy of a phase 2, double-blind, parallel-group, placebo-controlled, randomised trial
The Lancet Diabetes & Endocrinology · 2025 · peer-reviewed original research (randomized, double-blind, placebo-controlled phase 2 substudy)
Retatrutide for the treatment of obesity, obstructive sleep apnea and knee osteoarthritis: Rationale and design of the TRIUMPH registrational clinical trials
Diabetes, Obesity and Metabolism · 2026 · peer-reviewed trial design/rationale paper (phase 3 program description)
Efficacy and safety of retatrutide, a GIP, GLP-1, and glucagon receptor agonist, in people with type 2 diabetes and inadequate glycaemic control with diet and exercise (TRANSCEND-T2D-1): a double-blind, randomised, phase 3 trial
The Lancet · 2026 · peer-reviewed original research (randomized, double-blind, placebo-controlled phase 3 trial)
What is Retatrutide's reference identity, and why is formula/MW often shown as 'per COA'?+
Retatrutide is identified by CAS 2381089-83-2 and the investigational code LY3437943, but a batch specification must still state the complete modified sequence, terminal state, lipidation, free-peptide or salt basis and counter-ions. NCATS lists retatrutide and a related sodium form as distinct substance records. The COA should report the theoretical mass basis used, the measured high-resolution intact mass and the acceptance rule for the supplied form; a catalogue number or an unqualified average molecular weight is not enough.
How is Retatrutide pharmacologically different from Tirzepatide?+
Tirzepatide is a dual GIPR/GLP-1R agonist, whereas Retatrutide also activates GCGR. Both are long-acting lipidated peptides, but their sequences, receptor pharmacology and clinical-development programs differ. Cross-trial results cannot establish molecule-to-molecule superiority; a direct comparator study is required for that conclusion.
What identity testing should a lab request when qualifying Retatrutide from a new source?+
Request the complete modified sequence and terminal state, high-resolution intact mass, LC-MS/MS or another orthogonal sequence method, RP-HPLC/UPLC chromatogram with impurity assignment, peptide-content assay, counterion identity, water and residual solvents. Specify aggregate, endotoxin or bioburden limits only when required by the experimental model. HPLC area purity and intact mass alone do not establish content or full sequence.
