Pricing & Sizes
Ships sealed and lyophilized — stable for years at room temperature, supplied as lyophilised powder. Free shipping on every order, no minimum. Every batch ships with its lab report. Reports come from third-party labs including Janoshik, Freedom Diagnostics and Chromate, most verifiable through the lab's own public portal. Ask and we will send the report for your batch.
Lab report on file. Current batch tested by Freedom Diagnostics — HPLC-UV + LC-MS, blind GLP-1 panel. Verifiable through the lab's public portal; ask and we will send it.
Reconstitution — bacteriostatic water: 10mg vial reconstituted at 2mL gives 5mg/mL; 20mg vial reconstituted at 2mL gives 10mg/mL. These are concentrations, calculated from vial content and diluent volume. They describe the solution, not a dose.
Email To OrderIn Plain English
Think of your metabolism as a restaurant kitchen. GLP-1 is the host at the door, seating fewer tables — less food comes in, and you stop wanting it as much. GIP is the chef deciding where each delivery goes: onto the line to be cooked, or into the walk-in freezer to sit. Push it one way and more of what you eat gets used instead of stored. Glucagon is the burners. Turn them up and the whole kitchen runs hotter, which means more energy spent even when nothing is being ordered. Semaglutide works on the host. Tirzepatide works on the host and the chef. Retatrutide is the first to reach the burners as well.
What people use it for. Weight loss, and it is the most effective option available for that purpose by a considerable margin.
What to know before you buy. The adverse events reported in the trials were almost entirely gastrointestinal — nausea, vomiting, diarrhoea — and they were dose-related, which is why the published trials escalated gradually. The other finding worth knowing: the leaner the participant, the less favourable the trade-off, because most of the available fat loss has already occurred while the lean mass cost continues.
What It's Studied For
| Research area | What that rests on |
|---|---|
| Body weight in trials | Phase II trial published in the New England Journal of Medicine reported ~24% mean reduction at 48 weeks on the top dose |
| Appetite signalling | GLP-1 and GIP receptor activation |
| Energy expenditure | The glucagon receptor component adds a mechanism dual agonists do not have |
| Glucose regulation | Incretin activity; consistent across the class |
The left column lists the research areas this compound is investigated in; the right column states what that rests on. These are published research findings, not proven outcomes or treatment claims, and nothing here is a recommendation. Sold for laboratory research use only.
At a Glance
- Class
- Triple agonist at GLP-1, GIP, and glucagon receptors
- Developer
- Eli Lilly
- Trial evidence
- Phase III has now reported. TRIUMPH-2 (type 2 diabetes with obesity or overweight) reported up to 20.8% mean weight reduction at 80 weeks; TRIUMPH-3 (severe obesity with established cardiovascular disease) up to 22.6%. Five late-stage trials have now read out positively. The earlier phase II result in the New England Journal of Medicine was around 24% at 48 weeks
- Status
- Investigational. Several phase III trials reached primary completion in 2026, including TRIUMPH-1 (2,335 participants) and the 1,946-participant cardiovascular outcomes trial. Others run to 2029. Lilly has opened a pre-approval expanded access programme. Not approved in any market
- Distinguishing feature
- The glucagon receptor component adds an energy expenditure mechanism that dual agonists lack
- Regulatory (US)
- Not FDA-approved. Not on the July 2026 PCAC agenda. As an investigational drug it is a separate regulatory matter from the 503A bulks list process
- Format
- 10mg vial
Regulatory status — investigational drug
Retatrutide is an investigational compound in late-stage development by Eli Lilly. Several phase III trials reached primary completion during 2026 and a pre-approval expanded access programme is now open, but it is not approved in any jurisdiction, and was not on the July 2026 PCAC agenda — that process concerns bulk substances for pharmacy compounding, which is a different question entirely. The trial figures on this sheet come from Lilly’s programme and describe the compound itself.
What the Trials Show
The phase II programme published in the New England Journal of Medicine reported dose-dependent weight reduction reaching roughly 24% mean loss at 48 weeks on the highest dose — the largest figure reported in a published obesity pharmacotherapy trial to date, and notably without a clear plateau by the end of the study period.
Adverse events were predominantly gastrointestinal — nausea, vomiting, diarrhoea — and dose-related, following the pattern seen across the incretin class. The dose-escalation schedules used in the published trials were gradual for that reason.
What Happens When You Stop
Appetite suppression is not a permanent change to how hunger works — it is suppression, held in place for as long as the compound is present. When it clears, appetite returns, and it returns to a body that now needs fewer calories than it did before, because it is smaller. Those two facts together are why regain after discontinuation is consistently high across the whole incretin class.
None of that is specific to retatrutide, and none of it means the compound failed. It is simply worth understanding before starting rather than after.
What to Weigh Before You Start
Gastrointestinal effects are the common ones
Nausea, vomiting and diarrhoea were the predominant adverse events in the trials, they were dose-related, and they are why the published trials escalated gradually rather than quickly.
Lean mass has a cost, and it rises as you get leaner
Rapid weight loss at this magnitude carries a lean mass penalty. There is no published human body-composition data specific to retatrutide, so anyone quoting you a percentage for this compound is extrapolating. What is established across the class is that the leaner you already are, the worse the trade becomes: most of the available fat is already gone, and the penalty keeps running.
The bottom line
The strongest efficacy data in the metabolic category, and the mechanism behind it is genuinely new rather than a better version of something older. The phase III programme began reading out during 2026 and Lilly has opened pre-approval expanded access — the stage a compound reaches shortly before it is filed.
Also in the Range
Compare with Tirzepatide, which has completed phase III and FDA approval behind the molecule but two receptor targets rather than three.