Retatrutide vs Wegovy: Triple Agonist vs GLP-1
Retatrutide produces nearly double the weight loss of Wegovy (28.7% vs 14.9%), but Wegovy has major advantages: it is available now in both injectable and oral form, has proven cardiovascular protection (the SELECT trial), and has over 5 years of real-world safety data.
Side-by-Side Comparison
| Retatrutide | Wegovy (Semaglutide) | |
|---|---|---|
| Mechanism | Triple agonist: GLP-1 + GIP + Glucagon | GLP-1 receptor agonist only |
| Manufacturer | Eli Lilly | Novo Nordisk |
| Max weight loss | -28.7% at 68 weeks (TRIUMPH-4, 12 mg) | -14.9% at 68 weeks (STEP 1, 2.4 mg) |
| Administration | Once-weekly injection | Once-weekly injection OR daily oral pill |
| Oral option | None | Yes — Wegovy oral approved Dec 2025 |
| FDA status | Not approved (Phase 3) | Approved (June 2021) |
| CV outcomes | Trial ongoing (TRIUMPH CVOT) | 20% MACE reduction proven (SELECT) |
| Discontinuation (AEs) | 18.2% (12 mg) | 7.0% |
| Dysesthesia | 20.9% at 12 mg | Not observed |
| Monthly cost | Not yet available (~$1,200–1,500 projected) | $1,349 injectable; $149–299 oral (cash) |
How the Mechanisms Differ
Wegovy (semaglutide) targets the GLP-1 receptor only. It suppresses appetite through hypothalamic signaling, slows gastric emptying, enhances insulin secretion, and reduces glucagon release. It works primarily by reducing how much you eat.
Retatrutide adds GIP and glucagon receptor activation on top of GLP-1. The glucagon component increases resting energy expenditure through thermogenesis and promotes liver fat oxidation. Retatrutide works by reducing intake and increasing expenditure — both sides of the energy equation.
This mechanism difference explains the nearly 2x weight loss gap. For details, see How Does Retatrutide Work?.
Weight Loss Comparison
| Drug | Trial | Duration | Weight Loss |
|---|---|---|---|
| Retatrutide 12 mg | TRIUMPH-4 (Phase 3) | 68 weeks | -28.7% |
| Retatrutide 9 mg | TRIUMPH-4 (Phase 3) | 68 weeks | -26.4% |
| Semaglutide 2.4 mg | STEP 1 | 68 weeks | -14.9% |
| Semaglutide 2.4 mg | STEP 3 (+ behavioral therapy) | 68 weeks | -16.0% |
| Semaglutide 7.2 mg (investigational) | STEP UP | 72 weeks | -20.7% |
Weight Loss Thresholds
| Threshold | Retatrutide 12 mg | Wegovy 2.4 mg |
|---|---|---|
| Lost at least 15% | 83.2% | 48.9% |
| Lost at least 20% | 72.5% | 35.5% |
| Lost at least 25% | 58.6% | 13.2% |
For a 250-lb person: retatrutide produces approximately 35 more pounds of weight loss than Wegovy (~72 lbs vs ~37 lbs).
Cardiovascular Protection: Wegovy's Advantage
Wegovy has a proven cardiovascular benefit that retatrutide does not yet have:
The SELECT Trial — a landmark study showing semaglutide 2.4 mg reduced major adverse cardiovascular events (heart attack, stroke, cardiovascular death) by 20% in adults with heart disease and obesity. This led to an expanded FDA indication for cardiovascular risk reduction and potential Medicare coverage.
Retatrutide's TRIUMPH CVOT is ongoing, with results expected in 2027-2028. Early blood pressure data is promising (retatrutide reduced systolic BP by -14.0 mmHg vs semaglutide's approximately -6 mmHg), but this has not been confirmed in a dedicated outcomes trial.
Wegovy's Oral Formulation
In December 2025, the FDA approved oral Wegovy (semaglutide 25 mg tablet) — the first oral GLP-1 for weight loss. This eliminates the injection barrier:
- Efficacy: 16.6% average weight loss (comparable to injectable Wegovy)
- Cash price: $149-299/month through telehealth providers
- No fasting required (unlike older oral semaglutide Rybelsus)
- One-third of participants lost 20%+ body weight
Retatrutide has no oral formulation in development. It is a peptide that requires injection.
Side Effects Comparison
| Retatrutide 12 mg | Wegovy 2.4 mg | |
|---|---|---|
| Nausea | 43% | 44% |
| Diarrhea | 33% | 30% |
| Vomiting | 21% | 24% |
| Discontinuation (AEs) | 18.2% | 7.0% |
| Dysesthesia | 20.9% | Not observed |
GI side effects are broadly similar. However, retatrutide has a notably higher discontinuation rate (18.2% vs 7.0%) and a unique dysesthesia signal (tingling/burning sensations) not seen with semaglutide.
Wegovy's advantage: over 5 years of real-world safety data from millions of patients, compared to retatrutide's trial-only experience.
Frequently Asked Questions
Is retatrutide better than Wegovy?
Retatrutide produces nearly double the weight loss (28.7% vs 14.9%). However, Wegovy is available now, has proven cardiovascular protection, an oral formulation, and lower discontinuation rates. "Better" depends on individual needs — maximum weight loss vs availability and proven safety.
Should I wait for retatrutide or start Wegovy now?
If you qualify for Wegovy (or Zepbound/Mounjaro), starting treatment now is reasonable. Retatrutide won't be available until late 2027 at the earliest. Talk to your doctor about currently approved options. See When Will Retatrutide Be Available?.
Can I switch from Wegovy to retatrutide later?
No studies have examined switching from semaglutide to retatrutide. If retatrutide is approved, your doctor could potentially transition you, but switching protocols have not been established.
Sources
- Jastreboff, A.M., et al. (2021). Semaglutide 2.4 mg for the Treatment of Obesity (STEP 1). NEJM. DOI: 10.1056/NEJMoa2032183.
- Lincoff, A.M., et al. (2023). Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes (SELECT). NEJM. DOI: 10.1056/NEJMoa2307563.
- Eli Lilly. (2025). TRIUMPH-4 results. Press release.
- Novo Nordisk. (2025). Wegovy Oral FDA Approval. Press release.
Medical Disclaimer
The content on glp3.wiki is for informational purposes only and does not constitute medical advice, diagnosis, or treatment. Retatrutide is an investigational drug. Wegovy is FDA-approved for specific indications.
Do not use this information to make decisions about your health without consulting a qualified healthcare provider.
This site is not affiliated with Eli Lilly, Novo Nordisk, or any pharmaceutical manufacturer.
Sources
Related reading
Zepbound vs Wegovy: Which Weight Loss Drug Is Better?
Zepbound produced -20.2% vs Wegovy's -13.7% weight loss in the SURMOUNT-5 head-to-head trial. Full comparison of cost, side effects, and CV data.
Ozempic vs Wegovy: Same Drug, Different Purpose
Ozempic and Wegovy both contain semaglutide. The difference: indication (diabetes vs weight loss), max dose (2.0 vs 2.4 mg), and insurance coverage.
What Is Retatrutide (GLP-3)?
The world's first triple agonist weight loss drug — how it works, what the trials show, and why people call it GLP-3.