Retatrutide Before and After: What the Clinical Data Actually Shows
Written by Alejandro Reyes
Founder & Lead Researcher
Reviewed by Peptide Nerds Editorial · Updated April 2026
Retatrutide Before and After: What the Clinical Data Actually Shows
Key takeaways:
- No public before/after photos from retatrutide trials exist. Clinical protocols prohibit individual participant imaging.
- Phase 3 data (February 2026): 12 mg retatrutide produced 28.7% body weight loss (71.2 lbs / 32.3 kg) over 68 weeks.
- Phase 2 data (NEJM 2023, PMID 37385275): 12 mg produced 24.2% body weight loss over 48 weeks in 338 participants.
- At 12 mg, retatrutide outperforms semaglutide (14.9%) and tirzepatide (22.5%) in Phase 3 comparisons.
- Retatrutide is NOT FDA-approved. It is only available through clinical trials.
Important: This article is for educational and informational purposes only. It is not medical advice. Retatrutide is an investigational compound not approved by the FDA for any indication. Always consult a qualified healthcare provider before making any health decisions. See our full medical disclaimer.
Why there are no real before/after photos
If you searched "retatrutide before and after" expecting transformation photos, you will not find them here. You will not find credible ones anywhere.
This is not an accident.
Clinical trial protocols at this scale do not produce public before/after photo collections. Participants in Phase 2 and Phase 3 trials sign detailed consent agreements. Individual images are not released to the public. Eli Lilly has not distributed participant photos, and publications in the New England Journal of Medicine do not include them.
Any photos circulating online labeled as retatrutide before/after results are unverified. They may come from people using compounded or unregulated versions of the drug. They may be mislabeled semaglutide or tirzepatide results. They may be fabricated entirely.
What we have instead is something more reliable: controlled trial data from 338 participants in Phase 2 and a larger Phase 3 cohort. The numbers tell a clearer story than any single photo could.
What "before and after" actually means in clinical data
When researchers measure a "before and after" outcome in a drug trial, they use standardized measurements taken at baseline (before) and at the end of the study (after). For retatrutide, the primary outcome is percentage of body weight lost.
This approach is more useful than photos for several reasons.
Photos capture one person's experience. The trial data captures the average across hundreds. A photo can be flattering or staged. A percentage is calculated from scale weights under controlled conditions. Photos do not tell you anything about the range of results. Trial data does.
Here is what the "before and after" picture actually looks like in numbers.
Phase 2 results: before to after at 48 weeks
The Phase 2 trial was published in the New England Journal of Medicine in 2023 (PMID: 37385275). It enrolled 338 adults with obesity or overweight with at least one weight-related condition. All participants received once-weekly subcutaneous injections for 48 weeks.
| Dose | Before (Baseline) | After 24 Weeks | After 48 Weeks |
|---|---|---|---|
| Placebo | 100% | -2.1% | -2.1% |
| 1 mg | 100% | -6.0% | -8.7% |
| 4 mg (escalated) | 100% | -12.9% | -17.1% |
| 4 mg (fixed) | 100% | -12.1% | -17.9% |
| 8 mg (escalated) | 100% | -17.3% | -22.8% |
| 12 mg (escalated) | 100% | -17.5% | -24.2% |
At 12 mg, participants lost 24.2% of their starting body weight by week 48.
To put that in concrete terms: for a person who weighed 250 pounds at the start, 24.2% means roughly 60 pounds lost. Their "after" weight would be approximately 190 pounds.
One critical detail in this data: weight loss was still accelerating at week 48. The 12 mg group went from 17.5% at 24 weeks to 24.2% at 48 weeks. The curve had not flattened. That raised an obvious question about what would happen with more time.
Phase 3 results: before to after at 68 weeks
The answer came in February 2026, when Eli Lilly released topline data from the TRIUMPH Phase 3 program. This specific trial enrolled participants with obesity and knee osteoarthritis. The "after" at 68 weeks:
| Dose | Weight Loss at 68 Weeks | Absolute Weight Lost |
|---|---|---|
| 9 mg | -26.4% | Not disclosed |
| 12 mg | -28.7% | 71.2 lbs (32.3 kg) |
At 12 mg over 68 weeks, the average participant lost 71.2 pounds.
For someone who started at 248 pounds, that means an "after" weight of approximately 177 pounds. That is a categorical change in body composition, not a modest trim.
The 9 mg dose produced 26.4% weight loss, which also exceeds every other obesity drug currently approved or in late-stage development.
For the full dose-by-dose breakdown and trial methodology, see our retatrutide weight loss results article. For the detailed clinical trial data across both phases, see our retatrutide clinical trials guide.
How retatrutide before/after results compare to other drugs
No direct head-to-head trial has been published. But we can compare the pivotal Phase 3 results across each drug's primary trial.
| Drug | Trial | Dose | Duration | Weight Loss |
|---|---|---|---|---|
| Semaglutide 2.4 mg (Wegovy) | STEP 1 | 2.4 mg | 68 weeks | -14.9% |
| Tirzepatide 15 mg (Zepbound) | SURMOUNT-1 | 15 mg | 72 weeks | -22.5% |
| Retatrutide 9 mg | TRIUMPH Phase 3 | 9 mg | 68 weeks | -26.4% |
| Retatrutide 12 mg | TRIUMPH Phase 3 | 12 mg | 68 weeks | -28.7% |
Retatrutide at 12 mg nearly doubles the weight loss produced by semaglutide at the same timepoint. It outperforms tirzepatide's highest approved dose by more than 6 percentage points.
Even retatrutide's lower 9 mg dose (26.4%) beats tirzepatide's 15 mg dose (22.5%).
Cross-trial comparisons have limitations. Patient populations, baseline weights, and study designs are not identical. But a 14-percentage-point gap between semaglutide and retatrutide is not explained by methodology differences alone.
The mechanism behind this gap is covered in depth on our retatrutide overview page. The short version: retatrutide activates three receptors (GLP-1, GIP, and glucagon), while semaglutide activates one and tirzepatide activates two. The added glucagon receptor component appears to contribute metabolic effects neither of the other drugs produce.
What the "after" looks like in real weight terms
Percentages can be abstract. Here is what a 28.7% reduction looks like at different starting weights:
| Starting Weight | 28.7% Loss | Ending Weight |
|---|---|---|
| 200 lbs | ~57 lbs | ~143 lbs |
| 225 lbs | ~65 lbs | ~160 lbs |
| 250 lbs | ~72 lbs | ~178 lbs |
| 275 lbs | ~79 lbs | ~196 lbs |
| 300 lbs | ~86 lbs | ~214 lbs |
These are population averages from the highest dose group. Individual results varied in the trials. The 28.7% figure is the mean, not a guaranteed floor.
What else changed beyond weight
Weight loss was not the only "after" measured. The TRIUMPH Phase 3 trial enrolled participants with obesity and knee osteoarthritis specifically because Eli Lilly wanted to demonstrate benefits beyond the scale.
The results on secondary outcomes were significant:
- 75.8% reduction in knee pain on the WOMAC pain scale (12 mg group)
- Substantial improvements in physical function scores
- Over 12% of participants became completely pain-free after treatment
Phase 2 substudy data published in The Lancet Diabetes and Endocrinology examined body composition using DEXA scans. The majority of weight lost was fat mass. Some lean mass loss did occur, which is expected with any significant weight loss intervention. But the fat-to-lean ratio was favorable compared to caloric restriction alone.
The glucagon receptor activation is the likely contributor. Glucagon promotes lipolysis (fat breakdown) while having less direct effect on muscle protein.
For a full breakdown of the safety data, see our retatrutide safety guide.
The weight loss trajectory over time
One of the more striking findings is that the "after" kept improving with additional time. Most obesity drugs show a plateau around months 6 to 9. Retatrutide has not shown this pattern in published data.
| Timepoint | Weight Loss (12 mg) |
|---|---|
| 24 weeks (Phase 2) | -17.5% |
| 48 weeks (Phase 2) | -24.2% |
| 68 weeks (Phase 3) | -28.7% |
The rate of loss does slow across time. But it does not stop. At 68 weeks, participants were still losing weight.
The likely explanation is the glucagon receptor agonism. While GLP-1 and GIP reduce appetite, glucagon receptor activation increases energy expenditure and promotes fat oxidation. This combination of eating less and burning more may prevent the metabolic adaptation that causes plateaus with GLP-1-only drugs.
How to access retatrutide right now
Retatrutide is not available through prescriptions, pharmacies, or telehealth platforms.
The only way to access retatrutide under legitimate, studied conditions is through a clinical trial. ClinicalTrials.gov lists current open TRIUMPH program trials. Eligibility criteria vary by trial arm.
Anything sold online as "retatrutide" is unregulated. It has not passed the manufacturing controls, purity verification, or dosing validation used in the trials. The results summarized in this article came from a controlled trial compound. That does not transfer to street-level products.
For more context on the regulatory timeline and enrollment, see our how to get retatrutide guide.
Frequently asked questions
What do retatrutide before and after results actually look like?
There are no public before/after photos from retatrutide clinical trials. What exists is controlled trial data showing an average of 28.7% body weight loss at 68 weeks (12 mg dose) in Phase 3. For a person starting at 250 pounds, that translates to roughly 72 pounds lost. Individual results vary.
How much weight do people lose on retatrutide?
In Phase 3 clinical trials, the 12 mg dose produced 28.7% body weight loss (71.2 lbs / 32.3 kg) at 68 weeks. The 9 mg dose produced 26.4% at the same timepoint. Phase 2 data showed 24.2% at 48 weeks. These are population averages from controlled trials, not guaranteed individual outcomes.
Why are there no retatrutide before and after photos online?
Clinical trial protocols do not produce public participant photos. Individual participant data is protected under the study's consent agreements. Any photos labeled as retatrutide before/after circulating online are unverified and may come from unregulated or mislabeled products.
How does retatrutide compare to semaglutide and tirzepatide results?
Based on Phase 3 pivotal trial data: semaglutide (STEP 1) produced 14.9% weight loss at 68 weeks; tirzepatide (SURMOUNT-1) produced 22.5% at 72 weeks; retatrutide produced 28.7% at 68 weeks. No direct head-to-head trial exists, but the gap is substantial across all three comparisons.
Is 28.7% weight loss typical for everyone on retatrutide?
No. 28.7% is the average across participants in one Phase 3 trial cohort. Individual results fall across a range. Some participants lose more, some less. Factors including baseline weight, metabolic health, adherence, and individual drug response all influence outcomes.
When will retatrutide be available as a prescription?
The earliest realistic FDA approval is late 2027 to 2028. Eli Lilly has not submitted a New Drug Application yet. Additional Phase 3 results from the TRIUMPH program are expected throughout 2026. See our retatrutide clinical trials guide for the current regulatory timeline.
Medical disclaimer
This article is for educational and informational purposes only. It does not constitute medical advice, diagnosis, or treatment. Retatrutide is an investigational compound not approved by the U.S. Food and Drug Administration for any indication. The clinical trial data referenced in this article reflects results from controlled research settings and may not reflect outcomes in uncontrolled or unsupervised use. Always consult a licensed healthcare provider before making decisions about any medication, supplement, or investigational compound. Peptide Nerds does not endorse the use of unapproved compounds outside of clinical trial settings.
Sources
- Jastreboff AM, et al. "Triple-Hormone-Receptor Agonist Retatrutide for Obesity." New England Journal of Medicine. 2023. PMID: 37385275
- Eli Lilly and Company. Lilly's retatrutide achieves significant weight loss and reduces knee pain in Phase 3 trial. Press release, February 2026.
- Jastreboff AM, et al. Tirzepatide Once Weekly for the Treatment of Obesity (SURMOUNT-1). NEJM. 2022. PMID: 35658024
- Wilding JPH, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1). NEJM. 2021. PMID: 33567185
- Body composition substudy data. The Lancet Diabetes and Endocrinology. 2024. (Phase 2 DEXA substudy)
This article was published on March 14, 2026. We update it as new Phase 3 data from the TRIUMPH program is released. For the full clinical breakdown, see our retatrutide weight loss results article or the retatrutide compound overview.
Free Peptide Weight Loss Guide
Semaglutide vs. tirzepatide vs. retatrutide. Dosing protocols, side effects, gray market sourcing, and what the clinical trials found.
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