Retatrutide in 2026: Trial Results and What's Next
Retatrutide, Lilly's GIP/GLP-1/glucagon triple agonist: TRIUMPH phase 3 results from July 2026, the planned 2027 FDA filing, and why online 'reta' is unsafe.
3 min read
Key takeaways
Retatrutide is an investigational weekly injection that acts on three hormone receptors: GIP, GLP-1 and glucagon. Lilly reported positive TRIUMPH-2 and TRIUMPH-3 phase 3 results in July 2026 and plans to submit to the FDA in Q1 2027. It is not approved anywhere.
Retatrutide at a glance
| Generic name | retatrutide |
|---|---|
| Made by | Eli Lilly |
| Type | GIP / GLP-1 / glucagon triple receptor agonist |
| Form | Weekly injection |
| How often | Once weekly |
| United States | Not FDA-approved. Lilly plans to submit to the FDA in Q1 2027 after positive TRIUMPH-2 and TRIUMPH-3 results (July 2026). |
| Canada | Not approved. |
Why a triple agonist
Adding glucagon-receptor activity to GIP and GLP-1 is designed to increase energy use as well as reduce appetite. In the phase 2 trial, the highest dose produced average weight loss of about 24% at 48 weeks.
What is being studied
The TRIUMPH phase 3 program covers obesity, knee osteoarthritis pain and obstructive sleep apnea, among other conditions.
Timeline
- July 2026: positive TRIUMPH-2 and TRIUMPH-3 results announced.
- Q1 2027: planned FDA submission.
- Approval would follow review — typically months later.
Why online “reta” is dangerous
Products sold as retatrutide online are unapproved, untested and of unknown content and dose. In August 2026 the FDA issued warning letters to online sellers of products marketed as retatrutide. Do not inject anything bought this way.
Frequently asked questions
Is retatrutide approved?
No. It is investigational, with an FDA submission planned for Q1 2027.
How is it different from tirzepatide?
Tirzepatide acts on GIP and GLP-1; retatrutide adds glucagon receptors.
How can I get it legally?
Only through a registered clinical trial — search ClinicalTrials.gov.
Keep reading
Sources
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General information based on the official label. It does not replace advice from your prescriber or pharmacist.