Key Takeaways
- Retatrutide (LY3437943) is an investigational weight loss medication developed by Eli Lilly
- Triple-agonist mechanism: First drug to activate GLP-1, GIP, and glucagon receptors simultaneously
- Phase 2 results: Up to 24.2% weight loss at 48 weeks (approximately 58 lbs for a 240-lb person)
- Not FDA-approved: Currently in Phase 3 clinical trials, expected approval in 2027–2028
- How it differs: Outperforms semaglutide (Ozempic/Wegovy) and tirzepatide (Mounjaro/Zepbound) in weight loss trials
- Access now: In the US, lawful access is limited to clinical trials (free) and Lilly's expanded access program (ClinicalTrials.gov NCT07629401), which a doctor must request, for adults with a BMI of 35 or more whose obesity has not responded to the highest available dose of current weight-loss treatment, who have two or more serious obesity-related complications, and who cannot join a trial. The FDA states retatrutide cannot be used in compounding under federal law.
What Is Retatrutide?
Retatrutide is an injectable medication currently being developed by Eli Lilly for the treatment of obesity and type 2 diabetes. It belongs to a class of drugs called incretin mimetics, but unlike existing medications (semaglutide targets one hormone pathway, tirzepatide targets two), retatrutide activates three metabolic receptors: GLP-1, GIP, and glucagon. In clinical trials, this triple-agonist approach has produced more weight loss than any other injectable medication tested so far.
In Phase 2 trials published in the New England Journal of Medicine in 2023, participants taking the highest dose (12mg weekly) lost an average of 24.2% of their body weight over 48 weeks. For someone weighing 240 pounds, that's about 58 pounds. That's roughly 2–3% more weight loss than tirzepatide (Mounjaro/Zepbound) and 9% more than semaglutide (Ozempic/Wegovy) at their respective maximum doses.
Investigational Drug Status
Important: Retatrutide is not FDA-approved. It's an investigational drug currently in Phase 3 clinical trials. Lilly plans to file with the FDA in Q1 2027, and approval would follow FDA review (likely 2027 or 2028). You cannot get a prescription for retatrutide at a retail pharmacy. In the US, the routes available today are a clinical trial or Lilly's narrow expanded access program (NCT07629401). The FDA states retatrutide cannot be used in compounding under federal law, so compounding pharmacies cannot lawfully supply it. For complete details on FDA status and approval timeline, see our guide: Is Retatrutide FDA Approved?
The Basics at a Glance
- Generic name: Retatrutide (development code: LY3437943)
- Manufacturer: Eli Lilly and Company
- Drug class: Triple agonist (GLP-1/GIP/glucagon receptor agonist)
- Administration: Once-weekly subcutaneous injection
- Dosing range: 2mg to 12mg weekly (gradual titration over 12+ weeks)
- Half-life: Approximately 6 days (reaches steady state in 4–5 weeks)
- FDA status: Phase 3 clinical trials (TRIUMPH program)
- Expected approval: 2027–2028
How Retatrutide Differs from Other GLP-1 Medications
To understand retatrutide, it helps to see where it fits in the evolution of GLP-1 class medications. Each generation has added more receptor targets, and each addition has produced better weight loss results.
The Progression: Single → Dual → Triple Agonist
| Medication | Brand Names | Mechanism | Max Weight Loss | FDA Status |
|---|---|---|---|---|
| Semaglutide | Ozempic, Wegovy | Single: GLP-1 only | ~15–17% | ✓ Approved |
| Tirzepatide | Mounjaro, Zepbound | Dual: GLP-1 + GIP | ~21–22% | ✓ Approved |
| Retatrutide | No brand name yet | Triple: GLP-1 + GIP + Glucagon | ~24% | Phase 3 trials |
More receptor targets has meant more weight loss. But the difference isn't just about numbers. Each receptor contributes something different.
What Each Receptor Does
GLP-1 (Glucagon-Like Peptide-1)
The foundation of all GLP-1 medications. Activates receptors in the brain to reduce appetite, slows gastric emptying (making you feel full longer), and stimulates insulin secretion from the pancreas. This pathway is responsible for the core appetite suppression effect.
GIP (Glucose-Dependent Insulinotropic Polypeptide)
Improves insulin sensitivity and appears to promote more favorable fat distribution (less visceral fat around organs, more subcutaneous fat under the skin). The addition of GIP to GLP-1 (as in tirzepatide) added approximately 5–7% more weight loss compared to GLP-1 alone.
Glucagon (The Unique Component)
This is what makes retatrutide different. Glucagon receptor activation increases your body's resting metabolic rate (you burn more calories at rest) and promotes lipolysis (the breakdown of stored fat into energy). It also helps mobilize liver fat, which is why retatrutide is being studied for fatty liver disease (NASH). This third mechanism likely explains the additional 2–3% weight loss beyond tirzepatide.
The short version: GLP-1 reduces how much you eat. GIP optimizes how your body uses that food. Glucagon increases how much you burn.
For more on the science behind these pathways, see our guide: How Does Retatrutide Work? The Triple Agonist Mechanism Explained.
Clinical Trial Results: What the Data Shows
The Phase 2 trial results were published in the New England Journal of Medicine in June 2023. The trial enrolled 338 adults with obesity (BMI ≥30) or overweight with comorbidities (BMI ≥27) and ran for 48 weeks.
Weight Loss Results by Dose
| Dose Group | Mean Weight Loss (%) | Mean Weight Loss (kg / lbs) | ≥15% Loss |
|---|---|---|---|
| Placebo | -2.1% | -2.0 kg / 4.4 lbs | 2% |
| 4mg weekly | -17.3% | -17.5 kg / 38.6 lbs | 75% |
| 8mg weekly | -22.8% | -24.2 kg / 53.4 lbs | 91% |
| 12mg weekly | -24.2% | -24.0 kg / 52.9 lbs | 93% |
What this means: At the highest dose, nearly everyone (100%) lost at least 5% of their body weight, and 93% lost at least 15% . The weight loss curve showed no plateau at 48 weeks, which suggests losses would likely continue beyond one year.
Beyond Weight Loss: Metabolic Improvements
Participants also saw improvements in cardiometabolic health markers:
- Blood pressure: Systolic BP decreased by 7.4 mmHg
- Triglycerides: Fell by 30%
- HDL cholesterol: Increased by 8% (the "good" cholesterol)
- Liver fat: Reduced by 50% based on imaging studies
- HbA1c: Decreased by 0.4% even in participants without diabetes
- Visceral fat: Reduced by 42% (more than total weight loss percentage)
Some of these improvements (particularly the visceral and liver fat reductions) are larger than the overall weight loss, which points to direct metabolic effects from the glucagon receptor activation.
Phase 3 Update (2026): Early data from the TRIUMPH-4 trial showed even more impressive results at 68 weeks: 28.7% average weight loss on the 12mg dose (approximately 71 lbs for a 240-lb person). Further Phase 3 results (TRIUMPH-1 in May 2026, TRIUMPH-2 and TRIUMPH-3 in July 2026) have since been reported.
For full clinical trial data and what to expect at each dose level, see our guide: Retatrutide Results: Clinical Trial Weight Loss Data & Timelines.
How Retatrutide Is Dosed
Retatrutide follows a gradual dose escalation protocol similar to other GLP-1 medications. Starting low and increasing slowly minimizes side effects and gives your body time to adjust.
Standard Titration Schedule
| Weeks | Weekly Dose | Purpose |
|---|---|---|
| 1–4 | 2mg | Initial tolerance assessment |
| 5–8 | 4mg | First therapeutic dose |
| 9–12 | 8mg | Full therapeutic range |
| 13+ | 12mg | Maximum dose (if needed) |
Dosing facts
- Injection frequency: Once weekly, on the same day each week
- Administration: Subcutaneous injection (under the skin) in the abdomen, thigh, or upper arm
- Half-life: Approximately 6 days, meaning it takes about 4–5 weeks to reach steady-state levels at each dose
- Storage: Lyophilized (freeze-dried) powder must be reconstituted with bacteriostatic water and stored at 2–8°C (refrigerated)
- Not everyone needs 12mg: Many users find 8mg sufficient for their weight loss goals
The 4-week intervals between dose increases aren't arbitrary; they match the drug's half-life. Waiting 4–5 weeks gets you to steady-state levels before increasing, which makes it easier to tell whether side effects come from the dose escalation or just normal fluctuation.
Microdosing option: Some people split their weekly dose into smaller, more frequent injections (e.g., 4mg twice weekly instead of 8mg once weekly) to reduce GI side effects. This approach isn't part of the clinical trial protocol but is common in the research peptide community. Learn more: Microdosing Retatrutide Guide.
For titration protocols, reconstitution instructions, and dosing calculations, see our guide: Retatrutide Dosing Guide: Full Dosing Chart & Calculator. You can also use our reconstitution calculator to determine exactly how many units to draw for your target dose.
Plan Your Retatrutide Journey
Use our free pharmacokinetic calculator to visualize how retatrutide builds up in your system and model your dosing schedule.
Retatrutide Side Effects: What to Expect
Like all GLP-1 class medications, retatrutide's most common side effects are gastrointestinal. The triple-agonist mechanism doesn't seem to cause different types of side effects than tirzepatide or semaglutide. It's more about degree and individual tolerance.
Most Common Side Effects (12mg Dose)
| Side Effect | Frequency | Typical Onset |
|---|---|---|
| Nausea | 45% | First 1–2 weeks after dose increase |
| Diarrhea | 15% | Days 1–7 post-injection |
| Constipation | 16% | Week 2+ at steady state |
| Vomiting | 19% | Peak drug levels (24–48 hrs post-dose) |
Frequency: Phase 2 trial data, 12mg group (Jastreboff et al., NEJM 2023; posted results, ClinicalTrials.gov NCT04881760), 48 weeks. In Phase 3 TRIUMPH-1 (Jastreboff et al., NEJM 2026; adults without diabetes, 80 weeks), the 12mg rates were nausea 42.4%, diarrhea 32.0%, constipation 26.1% and vomiting 25.3%.
When Side Effects Improve
Most side effects follow a predictable pattern:
- Peak: First 1–2 weeks at a new dose or when starting the medication
- Improvement: Week 3–4 as your body adapts (receptor desensitization, GI tract adjustment)
- Stabilization: By week 6+, most users report minimal or no side effects at the same dose
- Recurrence: Symptoms may temporarily return when you increase to the next dose (usually milder than initial onset)
Managing Side Effects
Nausea
- Eat smaller, more frequent meals instead of large portions
- Avoid fatty, greasy, or spicy foods (they slow gastric emptying further)
- Stay upright for 30–60 minutes after eating
- Ginger tea, peppermint, or over-the-counter anti-nausea medications (consult your provider)
Diarrhea
- Stay hydrated (electrolyte drinks if severe)
- Reduce fiber temporarily if diarrhea is acute
- Probiotics may help stabilize gut microbiome
- Anti-diarrheal medications (loperamide) if needed, under medical guidance
Constipation
- Increase water intake (aim for 2+ liters daily)
- Add fiber gradually (fruits, vegetables, psyllium husk)
- Light exercise stimulates bowel motility
- Stool softeners or osmotic laxatives (MiraLAX) if needed
When to Stop and Seek Medical Attention
Contact a healthcare provider immediately if you experience:
- Severe, persistent abdominal pain (could indicate pancreatitis)
- Signs of dehydration from vomiting/diarrhea (dizziness, dark urine, rapid heartbeat)
- Allergic reaction (hives, difficulty breathing, swelling of face/throat)
- Vision changes or severe headaches
- Symptoms of gallbladder problems (pain in upper right abdomen, yellowing of skin/eyes)
For side effect management strategies and what to watch for long-term, see our guide: Retatrutide Side Effects: Complete Guide & Management Strategies.
Who Should (and Shouldn't) Use Retatrutide
Since retatrutide isn't FDA-approved yet, there are no official prescribing guidelines. But the Phase 2/3 trial eligibility criteria give a good sense of who the medication is designed for.
Who It's For (Based on Trial Inclusion Criteria)
- BMI ≥30 (obesity) OR BMI ≥27 with at least one weight-related comorbidity (type 2 diabetes, hypertension, high cholesterol, sleep apnea)
- Adults ages 18–75 (some trials include narrower age ranges)
- People who have tried lifestyle interventions (diet and exercise) without sufficient weight loss
- Those with type 2 diabetes seeking both glucose control and weight loss
- People with obesity-related conditions that would improve with major weight reduction
Who Should Avoid Retatrutide
Based on trial exclusion criteria and the drug's mechanism, retatrutide is likely not appropriate for:
- Pregnancy or breastfeeding: Not studied in these populations; GLP-1 drugs are generally contraindicated
- Personal or family history of medullary thyroid cancer (MTC): GLP-1 drugs carry a boxed warning for thyroid C-cell tumors in rodent studies
- Multiple Endocrine Neoplasia syndrome type 2 (MEN 2): Increased MTC risk
- History of pancreatitis: GLP-1 drugs may increase pancreatitis risk
- Type 1 diabetes: Not studied; retatrutide is for type 2 diabetes or obesity
- Severe gastrointestinal disease: The GI side effects may worsen existing conditions (gastroparesis, IBD)
- Recent weight loss surgery: Interactions with surgical changes not well-studied
Important: Because retatrutide is not FDA-approved, anyone using it outside a clinical trial or Lilly's expanded access program is using an unapproved drug that no compounding pharmacy can lawfully supply. This means you're self-experimenting with an unapproved medication without the safety net of regulatory oversight. If you're considering retatrutide, the safest path is enrollment in a clinical trial where you'll receive pharmaceutical-grade medication with full medical supervision.
Special Populations
Type 2 Diabetes
Retatrutide has been studied specifically in adults with obesity or overweight and type 2 diabetes in the Phase 3 TRIUMPH-2 trial (The Lancet, 2026), which reported both substantial weight loss and improved glucose control. However, if you're on insulin or sulfonylureas, dose adjustments may be needed to prevent hypoglycemia.
Older Adults (65+)
Phase 2 trials included adults up to age 75. Older adults may be more sensitive to appetite suppression and weight loss, requiring more conservative dosing or closer monitoring. Muscle preservation through resistance training and adequate protein matters even more in this age group.
Kidney or Liver Impairment
No specific dose adjustments are recommended for mild-to-moderate renal or hepatic impairment based on tirzepatide data (similar peptide). Severe impairment hasn't been studied extensively. The glucagon component's effect on liver metabolism warrants caution in those with existing liver disease.
How to Access Retatrutide Now
Since retatrutide isn't FDA-approved, you can't get it through a standard prescription at a retail pharmacy. But people are using it today. Here are the routes people mention. In the US, only the first is lawful, alongside Lilly's expanded access program described below:
1. Clinical Trial Enrollment (Recommended)
Eli Lilly has run retatrutide trials across the United States and globally. Most retatrutide Phase 3 trials are no longer enrolling; check ClinicalTrials.gov for open studies. A trial is the safest way to access retatrutide. In the US, the other route available today is Lilly's narrow expanded access program (NCT07629401).
- Pros: Free pharmaceutical-grade medication, full medical supervision, regular lab work and monitoring, compensation for time and travel
- Cons: You may receive placebo instead of retatrutide (trials are randomized), strict eligibility criteria, time commitment (regular site visits over 1–2 years)
- How to find trials: Visit ClinicalTrials.gov and search for "retatrutide," or use Lilly Trial Guide to find recruiting sites near you
2. Compounding Pharmacies (Not a Lawful Route)
The FDA states that retatrutide cannot be used in compounding under federal law, so compounding pharmacies cannot lawfully supply it, with or without a prescription. The FDA has also warned telehealth companies for marketing retatrutide, API distributors for selling it to compounders, and outsourcing facilities for repackaging it.
- Status: Not lawful. A "compounded retatrutide" offer is not a legal alternative to a clinical trial.
- Details: See our guide to compounded retatrutide and its legal status. For cost context, see our retatrutide cost guide.
3. Research Peptide Vendors (Grey Market)
The majority of retatrutide in circulation comes from research peptide vendors who sell it as "not for human consumption." The FDA has warned companies that illegally sold unapproved retatrutide falsely labeled "for research purposes" or "not for human consumption." Quality varies widely between vendors.
- Pros: Much cheaper ($40–$120 per 5mg vial, translating to $150–$500/month depending on dose), no prescription required, widely available
- Cons: No quality control, contamination risk, no medical oversight, not lawful (the FDA has warned sellers), no recourse if something goes wrong
- Risk mitigation: Third-party testing through labs like Janoshik, vetting vendors through Reddit and peptide forums, starting with small test orders
Grey Market Risks
Research peptides are not FDA-regulated. There's no guarantee what's in the vial matches the label. Underdosing, overdosing, contamination, and outright fakes have all been documented. Testing costs $50–100 per sample. Community forums maintain vendor reputation lists, but that's the only quality enforcement mechanism. This is informed self-experimentation, not a safe alternative to approved drugs.
For cost comparisons, vendor considerations, and what to expect at each access point, see our guide: Retatrutide Cost: 2026 Pricing Guide (All Sources).
Model Your Retatrutide Protocol
Visualize how retatrutide builds up in your system, when you'll reach steady state, and how different doses compare using our free pharmacokinetic calculator.
When Will Retatrutide Be FDA Approved?
Based on Eli Lilly's public statements and typical FDA timelines, retatrutide approval is most likely in late 2027 or early 2028. Here's the projected timeline:
| Milestone | Estimated Date | Status |
|---|---|---|
| Phase 3 results (key trials) | December 2025 to July 2026 (key readouts) | Results reported |
| FDA submission (BLA) | Q1 2027 | Planned by Lilly |
| FDA review period | 6–12 months | Standard or priority review |
| Approval decision | Late 2027 – 2028 | Best-case scenario |
What Will Approval Mean?
- Commercial availability: Retatrutide will be manufactured at scale and distributed to retail pharmacies
- Insurance coverage: If approved for type 2 diabetes, most plans will cover it (with prior authorization). If approved for obesity, coverage will be inconsistent.
- Manufacturer savings programs: Eli Lilly will likely offer a savings card similar to Mounjaro's, potentially reducing out-of-pocket costs to $25–$50/month for commercially insured patients
- Projected price: List price estimated at $1,000–$1,500/month based on tirzepatide's pricing
- Brand name: Eli Lilly will give it a commercial brand name (similar to tirzepatide becoming "Mounjaro" and "Zepbound")
For more on FDA status, trial progress, and what approval will mean for access and cost, see our guide: Is Retatrutide FDA Approved? Status, Trials & Timeline (2026).
Frequently Asked Questions
What is retatrutide used for?
Retatrutide is being developed for the treatment of obesity and type 2 diabetes. It's an investigational triple-agonist medication that activates GLP-1, GIP, and glucagon receptors to produce significant weight loss and improve metabolic health. Phase 2 trials showed up to 24.2% weight loss at 48 weeks. It's also being studied for fatty liver disease (NASH) and cardiovascular outcomes. Retatrutide is not yet FDA-approved.
How does retatrutide work?
Retatrutide works by activating three hormone receptors simultaneously: GLP-1 (reduces appetite and slows digestion), GIP (improves insulin sensitivity and fat distribution), and glucagon (increases energy expenditure and fat breakdown). This triple-agonist mechanism creates a three-pronged approach to weight loss: reduced food intake, improved metabolic efficiency, and increased calorie burning. For detailed mechanisms, see our guide: How Does Retatrutide Work?
Is retatrutide better than Ozempic or Mounjaro?
Clinical trial data suggests retatrutide produces more weight loss than semaglutide (Ozempic/Wegovy) or tirzepatide (Mounjaro/Zepbound). Retatrutide showed 24.2% weight loss vs. tirzepatide's 21% and semaglutide's 15–17%. However, these comparisons come from separate trials with different populations and durations. Head-to-head trials haven't been conducted yet. Also, retatrutide isn't FDA-approved, while Ozempic and Mounjaro are, so "better" depends on whether you prioritize efficacy or regulatory approval and availability.
What are the side effects of retatrutide?
The most common side effects are gastrointestinal. In the Phase 2 trial's 12mg group: nausea (45%), vomiting (19%), constipation (16%), and diarrhea (15%). These typically peak in the first 1–2 weeks after starting or increasing dose, then improve by weeks 3–4 as your body adapts. Other side effects include fatigue, injection site reactions, and modest increases in heart rate. Serious but rare side effects include pancreatitis, gallbladder problems, and allergic reactions. For complete management strategies, see our side effects guide.
When will retatrutide be available?
Retatrutide is expected to receive FDA approval in late 2027 or early 2028, assuming Phase 3 trials are successful. Until then, in the US, lawful access is limited to clinical trial enrollment (free, pharmaceutical-grade, medically supervised) and Lilly's narrow expanded access program (NCT07629401). The FDA states retatrutide cannot be used in compounding under federal law, so compounding pharmacies cannot lawfully supply it. Research peptide vendors ($150–$500/month, grey market) also sell it, and the FDA has warned companies for illegally selling it that way. Search for trials at ClinicalTrials.gov.
How much weight can you lose on retatrutide?
In Phase 2 trials, participants on the 12mg dose lost an average of 24.2% of their body weight over 48 weeks. For someone starting at 240 pounds, that's approximately 58 pounds. Individual results vary based on dose tolerance, adherence, lifestyle factors, and genetics. Phase 3 data at 68 weeks showed even higher results (28.7% average weight loss on 12mg). Most people can realistically expect 15–25% weight loss over one year if they reach therapeutic doses and make concurrent lifestyle changes. For complete trial data, see our results guide.
What is the starting dose of retatrutide?
The starting dose is 2mg once weekly for the first 4 weeks. After that, the dose is gradually increased every 4 weeks: 2mg → 4mg → 8mg → 12mg (maximum). This slow titration minimizes side effects and allows your body to adapt. Not everyone needs the maximum dose; many people find 8mg sufficient for their goals. For complete dosing protocols and reconstitution instructions, see our dosing guide.
What is the difference between retatrutide and tirzepatide?
Both are multi-agonist medications, but retatrutide activates three receptors (GLP-1 + GIP + glucagon) while tirzepatide activates two (GLP-1 + GIP). The glucagon component is unique to retatrutide and increases energy expenditure through thermogenesis and fat breakdown, contributing an extra 2–3% weight loss beyond tirzepatide. Tirzepatide is FDA-approved and commercially available; retatrutide is still in Phase 3 trials. For a detailed head-to-head comparison, see retatrutide vs tirzepatide.
Is retatrutide safe?
Phase 2 trial data showed retatrutide was generally well-tolerated, with a safety profile similar to other GLP-1 medications (semaglutide, tirzepatide). The most common side effects were gastrointestinal and manageable with gradual dose escalation. In Phase 3 TRIUMPH-1 (Jastreboff et al., NEJM 2026; adults with obesity or overweight without diabetes), 11.2% of participants on 12mg stopped due to adverse events, vs 4.6% on placebo. However, long-term safety beyond the roughly two years covered by the reported trials (80 weeks in TRIUMPH-1, with an extension to week 104) isn't yet established. That's what Phase 3 trials are designed to assess. Because it's not FDA-approved, using retatrutide outside of clinical trials means you're self-experimenting with an investigational drug.
Can I get retatrutide with a prescription?
Not through a retail pharmacy, because retatrutide isn't FDA-approved. A compounded prescription is not a lawful option either: the FDA states retatrutide cannot be used in compounding under federal law, and it has warned telehealth companies for marketing retatrutide. In the US, lawful access is limited to enrollment in a retatrutide clinical trial, where you receive pharmaceutical-grade medication with full medical supervision, and Lilly's narrow expanded access program (NCT07629401). For the legal detail, see our guide to compounded retatrutide. For costs, see our cost guide.
Start Planning Your Retatrutide Protocol
Whether you're in a clinical trial or researching for future use, our tools help you understand dosing, timing, and what to expect.
References
- Jastreboff AM, Kaplan LM, Frías JP, et al. Triple–Hormone-Receptor Agonist Retatrutide for Obesity — A Phase 2 Trial. N Engl J Med. 2023;389(6):514-526. PubMed
- Eli Lilly and Company. Lilly's retatrutide delivered up to 24% weight loss in phase 2 obesity study. Press release, June 26, 2023. Lilly Investor Relations
- ClinicalTrials.gov. Study of Retatrutide (LY3437943) in Participants With Obesity (TRIUMPH-1). Identifier: NCT05929066. ClinicalTrials.gov
- Wilding JPH, Batterham RL, Calanna S, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity. N Engl J Med. 2021;384(11):989-1002. PubMed
- Jastreboff AM, Aronne LJ, Ahmad NN, et al. Tirzepatide Once Weekly for the Treatment of Obesity. N Engl J Med. 2022;387(3):205-216. PubMed
- U.S. Food and Drug Administration. Drug Approval Process. Accessed February 17, 2026. FDA.gov
- U.S. Food and Drug Administration. FDA's Concerns with Unapproved GLP-1 Drugs Used for Weight Loss. Content current as of October 1, 2026. FDA.gov
- Bellido V, le Roux CW, Ekinci EI, et al. Retatrutide in adults with obesity and type 2 diabetes (TRIUMPH-2): a double-blind, parallel-group, randomised, placebo-controlled, phase 3 trial. Lancet. Published online September 29, 2026. doi:10.1016/S0140-6736(26)01861-1. PubMed
- Jastreboff AM, Kaplan LM, Davies MJ, et al. Retatrutide, a Triple Hormone Receptor Agonist, for Treatment of Obesity. N Engl J Med. Published online September 29, 2026. doi:10.1056/NEJMoa2604169. PubMed
- Eli Lilly Medical Information. What are the results of retatrutide from TRIUMPH-1 in participants with obesity or overweight without type 2 diabetes? TRIUMPH-1 adverse-event table, citing the NEJM paper. Lilly Medical Information
- Eli Lilly Medical Information. What are the preliminary results with retatrutide from TRIUMPH-4 in participants with obesity or overweight and osteoarthritis? TRIUMPH-4 preliminary results. Lilly Medical Information
- ClinicalTrials.gov. A Study of LY3437943 in Participants Who Have Obesity or Overweight. Identifier: NCT04881760. Posted results, adverse events. ClinicalTrials.gov
Medical Disclaimer
This article is for informational and educational purposes only. It does not constitute medical advice and should not replace professional medical consultation. Retatrutide is an investigational drug that is not FDA-approved. Any use of retatrutide outside of approved clinical trials is off-label and undertaken at your own risk. Always consult with a qualified healthcare provider before starting, stopping, or changing any medication. The information presented here is based on published clinical trial data and may not reflect the final approved prescribing information when and if FDA approval occurs.