COMPARISON
Retatrutide vs Tirzepatide
5 attributes held for at least one of the two. 5 differ. Each value carries the register it came from and the date that register was read.
Answer
Retatrutide is authorised or registered in 0 and Tirzepatide in 10 of the 10 registers read. Retatrutide: highest phase Phase 3 (20 phase 3 trials, 0 with posted results). Tirzepatide: highest phase Phase 4 (after approval). 4 registered trials include both.
States no view on which is preferable, safer or more effective. Not medical advice.
| Retatrutide | Tirzepatide | |
|---|---|---|
| Registered trials differs | 41 clinicaltrials.gov · 2026-10-03 | 309 clinicaltrials.gov · 2026-10-03 |
| FDA label differs | Not checked no record of "fdaLabel" for retatrutide | FDA-approved: MOUNJARO openfda · 2026-10-03T17:23:44.062Z |
| EU authorisation differs | Nothing on record ema read 2026-08-31 | Authorised ema · 2026-10-03 |
| EU authorised on differs | Not checked no record of "authorisedOn" for retatrutide | 2022-09-15 ema · 2026-10-03 |
| ATC code differs | Not checked no record of "atcCode" for retatrutide | A10BX16 ema · 2026-10-03 |
SIDE EFFECTS
Most common side effects, each beside its own placebo
| Side effect | Retatrutide | placebo | Tirzepatide | placebo |
|---|---|---|---|---|
| Nausea | 26.0% | 8.7% | 25.6% | 8.1% |
| Decreased appetite | 17.9% | 5.2% | 11.6% | 2.9% |
| Covid-19 | 14.9% | 14.8% | 15.5% | 16.0% |
| Diarrhoea | 14.2% | 8.7% | 21.2% | 8.3% |
| Constipation | 10.7% | 2.6% | 13.7% | 4.5% |
| Vomiting | 10.1% | 1.7% | 11.4% | 2.6% |
| Fatigue | 6.6% | 2.6% | - | - |
| Lipase increased | 5.5% | 3.5% | - | - |
| Hypertension | 5.2% | 2.9% | - | - |
| Gastrooesophageal reflux disease | 4.9% | 1.4% | - | - |
| Dyspepsia | - | - | 7.9% | 2.7% |
| Headache | - | - | 6.6% | 6.2% |
| Abdominal pain | - | - | 6.0% | 2.7% |
| Upper respiratory tract infection | - | - | 5.7% | 6.2% |
Trial register Retatrutide: 2 placebo-controlled trials; Tirzepatide: 19. Each peptide is compared with placebo in its own trials, not with the other: a dash means the event is not in that peptide's top list. Retatrutide side effects · Tirzepatide side effects
LEGAL STATUS
Approval in each country read
| Country | Retatrutide | Tirzepatide | Register |
|---|---|---|---|
| United States | Not on the register | FDA-approved | Regulator FDA |
| European Union | Not on the register | Authorised | Regulator EMA |
| United Kingdom | Not on the register | Authorised | Regulator MHRA |
| Canada | Not on the register | Authorised | Regulator Health Canada |
| Australia | Status unknown | Registered | TGA |
| Switzerland | Not on the register | Authorised | Regulator Swissmedic |
| Brazil | Not on the register | Registado | Regulator ANVISA |
| Serbia | Not on the register | Authorised | Regulator ALIMS |
| Singapore | Not on the register | Registered | Regulator HSA |
| Turkey | Not on the register | Ruhsatli | Regulator TITCK |
HEAD TO HEAD
4 registered trials include both
| NCT07165028 | A Master Protocol of Multiple Agents in Adults With Metabolic Dysfunction-Associated Steatotic Liver Disease (SYNERGY-Outcomes) RECRUITING · updated 2026-09-22 |
|---|---|
| 2025-522674-36-00 | N1T-MC-MALO: A Master Protocol for a Randomized, Controlled, Clinical Trial of Multiple Pharmacologic Agents in Adult Participants With Metabolic Dysfunction-A Not stated · updated 2026-09-21 |
| 2024-511450-49-00 | J1I-MC-GZBP: A Phase 3, Randomized, Double-Blind Study to Evaluate the Efficacy and Safety of Retatrutide Compared to Tirzepatide in Adults Who Have Obesity Not stated · updated 2026-08-14 |
| NCT06662383 | A Study of Retatrutide (LY3437943) Compared to Tirzepatide (LY3298176) in Adults Who Have Obesity ACTIVE_NOT_RECRUITING · updated 2026-07-20 |
Values reproduce public registers on the dates shown. This comparison states no view on which compound is preferable, safer or more effective. Not medical, legal or regulatory advice.
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