We report net peptide content, not just purity — so the milligrams you dose aren't padded with water and counter-ion. RP-HPLC purity and ESI-MS identity, on a lot-numbered COA.

Net peptide content on every lot's COA.

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Retatrutide

Name: Retatrutide
Brand: Lyochem
SKU: retatrutide

GIP / GLP-1 / glucagon tri-agonist · 39-mer metabolic research peptide

≥ 99.0%CAS 2381089-83-2GLP-1 & Metabolic Peptides

Overview

Lyochem supplies Retatrutide (investigational development code LY3437943) as a sequence-verified analytical reference standard for tri-agonist incretin research. It is a 39-residue synthetic peptide that engages three receptors — GIP, GLP-1, and glucagon — and it is the glucagon arm that separates it from the dual-agonist entities, layering a direct hepatic-energy-expenditure mechanism on top of the incretin signalling; that third axis is the mechanistic rationale offered for the larger body-composition readouts in its published Phase 2 metabolic-research literature. As an investigational molecule it is not an approved finished drug anywhere, and the material here is characterized and labelled strictly as a research reagent. Production volume for this peptide is far smaller than for Semaglutide or Tirzepatide, so the closely-eluting deletion-sequence profile of a low-throughput 39-mer SPPS run is the dominant analytical concern. Each lot is therefore released with RP-HPLC purity (gradient method, UV 214 nm), ESI-MS identity, sequence confirmation by LC-MS/MS, counter-ion content, and water content by Karl Fischer — with the tandem-MS sequence read recommended at first-time qualification, since intact mass alone cannot resolve a correct 39-mer from its deletion by-products. Bacterial endotoxin (LAL) and microbial limits are available on request for in vivo metabolic-model work. Fills run mg-scale for reproducible aliquoting; this is reference-grade research material, distinct from compounding-scale API supply.

Applications & buyer fit

What research workflows this standard is sourced for

GLP-1 and metabolic-peptide buyers run incretin-pathway, body-composition, glucose-regulation, and energy-expenditure studies. Because the receptor pharmacology is sequence-sensitive, qualifying a new source means confirming identity within 0.5 Da of theoretical by ESI-MS, sequence verification by tandem MS on the first lot, and lot-to-lot consistency for reproducible metabolic research. Lyochem supplies this class reference-grade and mg-scale — distinct from compounding-grade (g/kg) API supply.

Research-buyer fit

Academic Laboratories

Universities, medical schools, and government research institutes qualifying a reference standard for a method-development or in vivo workflow.

Biotech R&D Groups

Preclinical biotech and pharmaceutical discovery teams sourcing characterized peptides for receptor-pharmacology, screening, and method-development campaigns.

What ships with every lot

Per-lot Certificate of Analysis
Every release ships with its own batch-specific CoA — identity, purity, and the analytical scope agreed at quote stage, tied to the exact lot you receive.
Sample COA on request
Review a representative batch CoA before you order, so you can confirm the packet matches what your method or sponsor audit needs.
Research Use Only · B2B supply
Supplied strictly as a research reagent to research institutions — not a finished dosage form and not for human administration. Buyer qualification runs at the inquiry stage.

Specifications

CAS: 2381089-83-2
Appearance: White lyophilized powder
Purity (HPLC): ≥ 99.0%
Strength: 5 mg – 60 mg
Packaging: 10 vials/box · base pack (multiples of 10)
Half-life: ≈ 6 days
MOQ: On request
Lead time: 14–21 days
Storage: -20°C, protect from light

Documentation available on request

Lot-specific Certificate of Analysis (CoA)
RP-HPLC chromatogram with peak integration
ESI-MS identity confirmation (±0.5 Da)
Sequence verification by LC-MS/MS
Water content by Karl Fischer
SDS / MSDS
Counter-ion content (acetate / TFA)
Peptide content (% net peptide)
Bacterial endotoxin (LAL) on request — in vivo workflows

Regulatory note

Investigational compound in clinical development; not approved as a finished drug in any jurisdiction. Sold for Research Use Only under the receiving laboratory's institutional and jurisdictional regulations — not a finished dosage form and not labelled for human administration. Buyers are responsible for institutional biosafety review and verifying import eligibility in the destination market.

Selected literature

Coskun T, Urva S, Roell WC, et al. 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 Metab. 2022;34(9):1234-1247.e9.
Jastreboff AM, Kaplan LM, Frías JP, et al. Triple-Hormone-Receptor Agonist Retatrutide for Obesity - A Phase 2 Trial. N Engl J Med. 2023;389(6):514-526.
Rosenstock J, Frias J, Jastreboff AM, et al. 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. Lancet. 2023;402(10401):529-544.
Sanyal AJ, Kaplan LM, Frias JP, et al. Triple hormone receptor agonist retatrutide for metabolic dysfunction-associated steatotic liver disease: a randomized phase 2a trial. Nat Med. 2024;30(7):2037-2048.
Coskun T, Wu Q, Schloot NC, et al. 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. Lancet Diabetes Endocrinol. 2025;13(8):674-684.
Giblin K, Kaplan LM, Somers VK, Le Roux CW, Hunter DJ, Wu Q, Lalonde A, Ahmad N, Bethel MA. Retatrutide for the treatment of obesity, obstructive sleep apnea and knee osteoarthritis: Rationale and design of the TRIUMPH registrational clinical trials. Diabetes Obes Metab. 2026;28(1):83-93.

Frequently asked questions

Why is intact-mass confirmation alone insufficient to certify a 39-mer like Retatrutide, and what does Lyochem add?▾

At this length, the impurities that matter most are near-isobaric to the target. Single-residue deletions and aspartimide rearrangements co-elute closely on RP-HPLC and can fall within the resolution of intact-mass measurement, so a clean ESI-MS peak does not by itself prove the labelled sequence. We therefore run LC-MS/MS on the lot: the b/y-ion ladder confirms residue order across the full 39-mer and demonstrates the supplied sequence matches the label. The certificate carries the RP-HPLC purity, the ESI-MS intact mass against the theoretical value for the supplied form, and the tandem-MS sequence result together.

Why is Retatrutide's formula and average mass often certified 'per COA' rather than as a fixed catalog value?▾

The isolated material is a salt, and the counter-ion and residual water vary with the purification route and source. Those components change the average mass and the effective molecular formula of what is actually in the vial, so a single fixed catalog figure would misrepresent net peptide content for weighing. For an investigational lipidated 39-mer this matters directly to concentration accuracy in metabolic-model work. We confirm identity by ESI-MS against the theoretical mass for the specific supplied form and reproduce that lot-specific value on the certificate, so a lab cites the measured number for its actual material rather than a nominal one.

Related peptides

Buyers who view Retatrutide also ask about:

Tirzepatide

≥99.0%

GIP / GLP-1 dual receptor agonist · 39-mer metabolic research peptide

CAS: 2023788-19-2
Vial: 2 mg–120 mg

MOQ on requestView details →

Semaglutide

≥99.0%

GLP-1 receptor agonist · 31-mer metabolic research peptide

CAS: 910463-68-2
Vial: 2 mg–50 mg

MOQ on requestView details →

See full catalog

Retatrutide

GIP / GLP-1 / glucagon tri-agonist · 39-mer metabolic research peptide

≥ 99.0%CAS 2381089-83-2GLP-1 & Metabolic Peptides

Overview

Applications & buyer fit

What research workflows this standard is sourced for

Research-buyer fit

Academic Laboratories

Universities, medical schools, and government research institutes qualifying a reference standard for a method-development or in vivo workflow.

Biotech R&D Groups

Preclinical biotech and pharmaceutical discovery teams sourcing characterized peptides for receptor-pharmacology, screening, and method-development campaigns.

What ships with every lot

Per-lot Certificate of Analysis
Every release ships with its own batch-specific CoA — identity, purity, and the analytical scope agreed at quote stage, tied to the exact lot you receive.
Sample COA on request
Review a representative batch CoA before you order, so you can confirm the packet matches what your method or sponsor audit needs.
Research Use Only · B2B supply
Supplied strictly as a research reagent to research institutions — not a finished dosage form and not for human administration. Buyer qualification runs at the inquiry stage.

Specifications

CAS: 2381089-83-2
Appearance: White lyophilized powder
Purity (HPLC): ≥ 99.0%
Strength: 5 mg – 60 mg
Packaging: 10 vials/box · base pack (multiples of 10)
Half-life: ≈ 6 days
MOQ: On request
Lead time: 14–21 days
Storage: -20°C, protect from light

Documentation available on request

Lot-specific Certificate of Analysis (CoA)
RP-HPLC chromatogram with peak integration
ESI-MS identity confirmation (±0.5 Da)
Sequence verification by LC-MS/MS
Water content by Karl Fischer
SDS / MSDS
Counter-ion content (acetate / TFA)
Peptide content (% net peptide)
Bacterial endotoxin (LAL) on request — in vivo workflows

Regulatory note

Selected literature

Coskun T, Urva S, Roell WC, et al. 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 Metab. 2022;34(9):1234-1247.e9.
Jastreboff AM, Kaplan LM, Frías JP, et al. Triple-Hormone-Receptor Agonist Retatrutide for Obesity - A Phase 2 Trial. N Engl J Med. 2023;389(6):514-526.
Rosenstock J, Frias J, Jastreboff AM, et al. 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. Lancet. 2023;402(10401):529-544.
Sanyal AJ, Kaplan LM, Frias JP, et al. Triple hormone receptor agonist retatrutide for metabolic dysfunction-associated steatotic liver disease: a randomized phase 2a trial. Nat Med. 2024;30(7):2037-2048.
Coskun T, Wu Q, Schloot NC, et al. 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. Lancet Diabetes Endocrinol. 2025;13(8):674-684.
Giblin K, Kaplan LM, Somers VK, Le Roux CW, Hunter DJ, Wu Q, Lalonde A, Ahmad N, Bethel MA. Retatrutide for the treatment of obesity, obstructive sleep apnea and knee osteoarthritis: Rationale and design of the TRIUMPH registrational clinical trials. Diabetes Obes Metab. 2026;28(1):83-93.

Frequently asked questions

Why is intact-mass confirmation alone insufficient to certify a 39-mer like Retatrutide, and what does Lyochem add?▾

Why is Retatrutide's formula and average mass often certified 'per COA' rather than as a fixed catalog value?▾

Related peptides

Buyers who view Retatrutide also ask about:

Tirzepatide

≥99.0%

GIP / GLP-1 dual receptor agonist · 39-mer metabolic research peptide

CAS: 2023788-19-2
Vial: 2 mg–120 mg

MOQ on requestView details →

Semaglutide

≥99.0%

GLP-1 receptor agonist · 31-mer metabolic research peptide

CAS: 910463-68-2
Vial: 2 mg–50 mg

MOQ on requestView details →

See full catalog