GLP-3RT vs GLP-2T: which one?
Last updated November 10, 2026
Short answer
GLP-3RT posted the bigger average number in its trials. GLP-2T has more people, more weeks and more years of data behind it, and costs less per milligram. Neither has been tested against the other in a published head-to-head trial.
GLP-3RT Vial
★★★★★4.8/5 editorial scoreThe compound behind the biggest weight-trial numbers of the decade. Three receptors, one molecule, 13 lots with a COA on file.
GLP-2T Vial
★★★★★4.7/5 editorial scoreThe dual-agonist molecule with the deepest published record: 72-week data, a head-to-head win and the lowest price per mg in the catalog.
Side by side
| GLP-3RT | GLP-2T | |
|---|---|---|
| Research code | LY3437943 (retatrutide) | LY3298176 (tirzepatide) |
| Receptors | GLP-1 + GIP + glucagon | GLP-1 + GIP |
| Headline trial result | -24.2% at 48 weeks | -20.9% at 72 weeks |
| Largest trial | 1,949 people (TRIUMPH-3) | 2,539 people (SURMOUNT-1) |
| Regulatory status of the molecule | Investigational, filing planned Q1 2027 | Pharmaceutical version approved by prescription |
| Vial sizes | 10, 20, 40 mg | 10, 40 mg |
| Lowest price per mg | $7.50 | $4.13 |
| Lots with COA on file | 13 | 2 |
| Editorial score | 4.8/5 | 4.7/5 |
Trial results
Average body-weight change at the top studied dose. Sources: STEP 1 (NEJM 2021), SURMOUNT-1 (NEJM 2022), retatrutide phase 2 (NEJM 2023). Separate trials, not a head-to-head comparison.
The third receptor is the difference. Glucagon signalling raises energy expenditure, which is the leading explanation for why the triple agonist curve was still falling at week 48 while the dual agonist curve flattens later in its trial. How triple agonists work →
Price
At the 40 mg size GLP-2T is $165 and GLP-3RT is $300. Both drop 5% at 2 units and 10% at 5.
Which to pick
- Largest effect in trials: GLP-3RT.
- Longest safety and efficacy record: GLP-2T.
- Tightest budget: GLP-2T 40 mg.