At a glance
| Retatrutide | Tirzepatide | |
|---|---|---|
| What it is | Triple agonist · GLP-1 / GIP / Glucagon | Dual agonist · GIP / GLP-1 |
| Group | Metabolic | Metabolic |
| Molecular formula | C221H342N46O68 | C225H348N48O68 |
| Molecular weight | 4731.3 g/mol | 4813.45 g/mol |
| CAS | 2381089-83-2 | 2023788-19-2 |
| Cited literature | 3 human studies cited | 3 human studies cited |
| Studies cited | 3 human · 0 animal · 0 cell · 0 review | 3 human · 0 animal · 0 cell · 0 review |
| Certificate | Third-party report for lot RT20260602, 99.507% purity, verification key on the product page | Third-party report for lot CS-ze10-0408, 99.764% purity, verification key MQIPS86NBTAX |
| Sizes and price | 10mg $110 · 20mg $200 (out of stock) | 10mg $80 · 20mg $160 (out of stock) |
| Availability | In stock | In stock |
| Storage | Lyophilised, −20°C, dark | Lyophilised, −20°C, dark |
Retatrutide
A single-molecule triple receptor agonist acting on GLP-1, GIP and glucagon receptors. The most requested compound in current metabolic research.
Retatrutide is a synthetic peptide with the molecular formula C221H342N46O68 and a molecular weight of 4731.3 g/mol, CAS registry number 2381089-83-2. The vial is sealed and lot-numbered, holds lyophilised powder, and is kept at −20°C protected from light until it ships.
Retatrutide carries the Eli Lilly development code LY3437943. It is a 39-amino-acid synthetic peptide and, at the time of writing, remains an investigational compound in late-stage clinical trials. It is not an approved medicine in any country, and the research vial is not the trial material.
The 3 papers cited below are 3 studies in humans. The human data belong to the pharmaceutical forms of the compound, not to any research-grade vial.
Cited on the Retatrutide page
- Jastreboff AM et al. (2023). Triple-Hormone-Receptor Agonist Retatrutide for Obesity - A Phase 2 Trial. N Engl J Med. PubMed 37366315 · SummaryPhase 2, 338 adults with obesity: mean weight change of −24.2% at 48 weeks on 12 mg weekly, against −2.1% on placebo.
- Rosenstock J et al. (2023). 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. PubMed 37385280 · SummaryPhase 2 in type 2 diabetes, 36 weeks: HbA1c fell by up to about two percentage points and body weight by up to about 17% at the highest dose.
- Coskun T et al. (2022). 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. PubMed 35985340 · SummaryThe discovery paper: how the three receptor activities were balanced in one molecule, with first-in-human data supporting once-weekly dosing.
Tirzepatide
A dual GIP and GLP-1 receptor agonist. The compound that established dual agonism as more effective than GLP-1 alone in metabolic research models.
Tirzepatide is a synthetic peptide with the molecular formula C225H348N48O68 and a molecular weight of 4813.45 g/mol, CAS registry number 2023788-19-2. The vial is sealed and lot-numbered, holds lyophilised powder, and is kept at −20°C protected from light until it ships.
Tirzepatide carries the Eli Lilly development code LY3298176. The approved pharmaceutical forms are marketed as Mounjaro and Zepbound in the United States. A research-grade vial is a different product from the approved drug: it is not manufactured, tested or labelled to pharmaceutical standards and is not a substitute for it.
The 3 papers cited below are 3 studies in humans. The human data belong to the pharmaceutical forms of the compound, not to any research-grade vial.
Cited on the Tirzepatide page
- Garvey WT et al. (2023). Tirzepatide once weekly for the treatment of obesity in people with type 2 diabetes (SURMOUNT-2): a double-blind, randomised, multicentre, placebo-controlled, phase 3 trial. Lancet. PubMed 37385275 · SummarySURMOUNT-2, adults with obesity and type 2 diabetes, 72 weeks: −12.8% (10 mg) and −14.7% (15 mg) body weight against −3.2% on placebo.
- Frías JP et al. (2021). Tirzepatide versus Semaglutide Once Weekly in Patients with Type 2 Diabetes. N Engl J Med. PubMed 34170647 · SummarySURPASS-2, 40 weeks head-to-head with semaglutide 1 mg: larger HbA1c and weight reductions at all three tirzepatide doses.
- Coskun T et al. (2018). LY3298176, a novel dual GIP and GLP-1 receptor agonist for the treatment of type 2 diabetes mellitus: From discovery to clinical proof of concept. Mol Metab. PubMed 30473097 · SummaryThe discovery paper: a GIP-biased dual agonist with a fatty diacid for weekly dosing, and its first clinical proof of concept.
Handling the two side by side
Retatrutide
- A long acylated peptide. Repeated warming and cooling of a solution can cause aggregation, seen as cloudiness; aliquot rather than re-cool the same vial.
- Lyophilised powder is stable for years at −20°C in the dark and tolerates days at ambient temperature in transit.
Tirzepatide
- A long acylated peptide. Repeated warming and cooling of a solution can cause aggregation, seen as cloudiness; aliquot rather than re-cool the same vial.
- Lyophilised powder is stable for years at −20°C in the dark and tolerates days at ambient temperature in transit.
Where to go next
- Retatrutide and Tirzepatide: full specifications, stability notes, references and the certificate for the lot in stock.
- GLP-1 family comparison: how the whole group compares.
- How to read a certificate of analysis and the certificates page.