Peptides for weight loss, ranked by human evidence

If you want a peptide for weight loss with real human evidence behind it, the answer is short: tirzepatide, semaglutide, and liraglutide. All three are FDA-approved GLP-1 drugs tested in large randomized trials. Below them sit investigational agents that work in trials but cannot lawfully be obtained, and below those sits a group of heavily marketed peptides, including AOD-9604 and 5-amino-1MQ, with no published human weight loss data at all.

This list ranks every weight-related compound in our dataset by that evidence. Our obesity page covers chronic weight management as a condition and our fat loss page covers body composition; this page ranks the peptides people search for by name. For brand-level GLP-1 comparisons, start at the GLP-1 hub.

How we ranked weight loss peptides

We ordered the list by three criteria, in this order:

1. Evidence grade. Human randomized trials first, then observational human data, then animal-only work. Grades come from each peptide's record.
2. Lawful access. Within a grade, a drug approved for weight management ranks above one approved for a narrower use, which ranks above one with no lawful route at all.
3. Size and length of the effect in the best available trial.

Statuses and prices were verified on September 22, 2026. Prices change often; each cost page carries its own verification date.

The ranking at a glance

• 1 to 3, approved for weight management, human trials: tirzepatide, semaglutide, liraglutide.
• 4 to 6, approved, but not for general weight loss: dulaglutide, setmelanotide, tesamorelin.
• 7 to 11, human trials, no lawful access: retatrutide, cagrilintide, survodutide, mazdutide, tesofensine.
• 12 to 14, animal only: AOD-9604, 5-amino-1MQ, adipotide.

1. Tirzepatide (Zepbound, Mounjaro)

• GradeEvidence: Human RCT
• StatusRegulatory: FDA approved
• WADAWADA: Not prohibited

Tirzepatide activates both the GIP and GLP-1 receptors. In SURMOUNT-1, 2,539 adults with obesity or overweight and no diabetes lost a mean 20.9% of body weight on the highest dose over 72 weeks, compared with 3.1% on placebo. [1] In SURMOUNT-5, the first head-to-head obesity trial against semaglutide, tirzepatide produced a mean loss of 20.2% versus 13.7%. [2] Zepbound is approved for chronic weight management in adults with obesity, or overweight with a weight-related condition, and for moderate to severe obstructive sleep apnea in adults with obesity. [3]

As of September 22, 2026, the manufacturer lists self-pay Zepbound at 299 USD a month at the starting dose, rising to 699 USD at the higher doses. [4] See the tirzepatide cost page for insurance and savings programs, and Zepbound vs Mounjaro for the difference between the two brands.

2. Semaglutide (Wegovy, Ozempic)

• GradeEvidence: Human RCT
• StatusRegulatory: FDA approved
• WADAWADA: Not prohibited

Semaglutide is the most studied drug on this list. In STEP 1, 1,961 adults lost a mean 14.9% of body weight over 68 weeks, compared with 2.4% on placebo. [5] In SELECT, 17,604 adults with overweight or obesity and established cardiovascular disease, but no diabetes, had a 20% lower risk of major adverse cardiovascular events (hazard ratio 0.80). [6] Wegovy is approved for chronic weight management and to reduce cardiovascular risk in adults with established cardiovascular disease and obesity or overweight. [7]

As of September 22, 2026, manufacturer self-pay prices run 149 to 499 USD a month depending on product and dose, with the Wegovy pen at 349 USD. [8] The list price is set to fall to 675 USD a month on January 1, 2027. [9] Eligible Medicare Part D enrollees pay 50 USD a month for Wegovy under the Medicare GLP-1 Bridge, which runs from July 2026 through December 2027. [10] Compare the two leaders on semaglutide vs tirzepatide, read the SURMOUNT-5 breakdown, and check current prices on the semaglutide cost page.

3. Liraglutide (Saxenda)

• GradeEvidence: Human RCT
• StatusRegulatory: FDA approved
• WADAWADA: Not prohibited

Liraglutide is an older, once-daily GLP-1 drug. In the SCALE trial, 3,731 adults without diabetes lost a mean 8.4 kg over 56 weeks, compared with 2.8 kg on placebo, and 63.2% versus 27.1% lost at least 5% of body weight. [11] Saxenda is approved for chronic weight management in adults and in adolescents aged 12 and older with obesity. [12] FDA approved the first generic liraglutide in December 2024, which has brought lower-priced versions to pharmacies. [13] The effect is smaller than with the weekly drugs above; see tirzepatide vs liraglutide.

4. Dulaglutide (Trulicity)

• GradeEvidence: Human RCT
• StatusRegulatory: FDA approved for type 2 diabetes
• WADAWADA: Not prohibited

Dulaglutide is approved to improve blood sugar control in type 2 diabetes and to reduce cardiovascular risk in adults with type 2 diabetes. It is not approved for weight management. [14] In AWARD-11, 1,842 adults with type 2 diabetes on metformin were randomized to three doses, and the higher doses gave dose-related additional reductions in HbA1c and body weight. [15] Weight loss is a secondary effect here, and prescribing it for weight alone is off-label.

5. Setmelanotide (Imcivree)

• GradeEvidence: Human RCT
• StatusRegulatory: FDA approved for rare genetic obesity
• WADAWADA: Not prohibited

Setmelanotide activates the MC4 receptor in the brain's appetite pathway. It is approved only for obesity caused by POMC, PCSK1, or LEPR deficiency or by Bardet-Biedl syndrome, confirmed by genetic testing. [17] In single-arm phase 3 trials, 80% of participants with POMC deficiency and 45% with LEPR deficiency lost at least 10% of body weight at one year. [16] It is not an option for common obesity. See semaglutide vs setmelanotide.

6. Tesamorelin (Egrifta)

• GradeEvidence: Human RCT
• StatusRegulatory: FDA approved for HIV lipodystrophy
• WADAWADA: Prohibited

Tesamorelin is a growth hormone releasing hormone analog approved only to reduce excess abdominal fat in adults with HIV and lipodystrophy. [19] In two pooled phase 3 trials of 806 patients, visceral fat fell by 24 square centimeters on tesamorelin and rose by 2 on placebo at 26 weeks, with no change in fat under the skin of the abdomen. [18] That is a visceral fat effect, not an overall weight loss effect.

Tesamorelin is a biologic: Egrifta moved to a biologics license (BLA 022505) on March 23, 2020, and FDA states that biological products are not eligible for the 503A or 503B compounding exemptions, so compounded tesamorelin has no lawful basis. [21] [40] Egrifta WR, by prescription, is the only lawful product, and prescribing it for fat loss in people without HIV is an off-label use with little trial support. One 28-day Egrifta WR kit was listed at about 10,709 USD retail as of September 22, 2026. [20] See the tesamorelin cost page, tesamorelin vs retatrutide, and how tesamorelin prescriptions work.

7. Retatrutide

• GradeEvidence: Human RCT
• StatusRegulatory: Clinical trials only
• WADAWADA: Prohibited

Retatrutide activates GIP, GLP-1, and glucagon receptors. In its phase 2 obesity trial, 338 adults lost a mean of up to 24.2% of body weight at the highest dose over 48 weeks, compared with 2.1% on placebo. [22] The first phase 3 results, published in 2026, showed significant improvements in blood sugar and weight in 537 adults with type 2 diabetes. [23]

It is not approved anywhere. It is not a component of an approved drug and is not on the 503A bulks list, so it cannot lawfully be compounded, and anything sold as retatrutide outside a trial is an unapproved drug. [29] Follow approval news on the retatrutide regulatory tracker and the phase 3 status post, see why there is no lawful price on the retatrutide cost page, and compare it on tirzepatide vs retatrutide. The only lawful route today is a clinical trial, covered in how to get retatrutide.

8. Cagrilintide (CagriSema with semaglutide)

• GradeEvidence: Human RCT
• StatusRegulatory: Not approved
• WADAWADA: Prohibited

Cagrilintide is a long-acting amylin analog. On its own, in a 26-week phase 2 trial of 706 adults, it produced up to 10.8% weight loss at the highest dose, versus 3.0% on placebo and 9.0% on liraglutide. [24] Combined with semaglutide in REDEFINE 1, 3,417 adults lost a mean 20.4% over 68 weeks versus 3.0% on placebo. [25] Neither form is approved, and it cannot lawfully be compounded. See semaglutide vs cagrilintide.

9. Survodutide

• GradeEvidence: Human RCT
• StatusRegulatory: Not approved
• WADAWADA: Prohibited

Survodutide is a glucagon and GLP-1 dual agonist. In SYNCHRONIZE-1, 725 adults without diabetes lost a mean 13.0% on the higher maintenance dose over 76 weeks, compared with 5.4% on placebo. [26] It is also being studied for fatty liver disease. It is not approved and cannot lawfully be compounded; see semaglutide vs survodutide.

10. Mazdutide

• GradeEvidence: Human RCT
• StatusRegulatory: Not approved in the United States
• WADAWADA: Unclear

Mazdutide is another GLP-1 and glucagon dual agonist, developed mainly in China. In GLORY-1, 610 Chinese adults lost a mean 14.0% on the higher dose over 48 weeks, while the placebo group gained 0.3%. [27] Any product sold as mazdutide in the United States is an unapproved drug. See survodutide vs mazdutide.

11. Tesofensine

• GradeEvidence: Human RCT
• StatusRegulatory: Not approved in the United States
• WADAWADA: Unclear

Tesofensine is not a peptide. It is a small molecule that blocks the reuptake of dopamine, norepinephrine, and serotonin, and it appears here because it is marketed alongside weight loss peptides. In a 24-week phase 2 trial of 203 adults with obesity on a reduced-calorie diet, weight loss ranged from 6.7 to 12.8 kg across doses versus 2.2 kg on placebo, and heart rate and blood pressure rose at the highest dose. [30] It has no US approval and no basis for compounding. See tesofensine vs semaglutide.

12. AOD-9604

• GradeEvidence: Animal only
• StatusRegulatory: Removed from Category 2, no active nomination
• WADAWADA: Prohibited

AOD-9604 is a modified fragment of the tail end of human growth hormone. In obese mice, chronic treatment increased fat oxidation and reduced body weight. [31] We found no indexed human trial reporting weight loss. FDA placed it in Category 2 in 2023; its April 2026 update lists it as a withdrawn nomination, which is not the same as being on the bulks list, so there is still no lawful basis to compound it. [32] WADA covers it under S2. [39] See AOD-9604 vs semaglutide.

13. 5-amino-1MQ

• GradeEvidence: Animal only
• StatusRegulatory: Not listed
• WADAWADA: Prohibited

5-amino-1MQ is a small molecule that blocks the enzyme NNMT; it is not a peptide either. In mice on a high-fat diet, NNMT inhibitors reversed diet-induced obesity. [33] There is no published human study. It is not on the 503A bulks list and has no USP monograph, so despite being marketed as a compounded capsule it has no lawful compounding basis. [29] Compare it with AOD-9604 vs 5-amino-1MQ, and read the longer 5-amino-1MQ fat loss post.

14. Adipotide

• GradeEvidence: Animal only
• StatusRegulatory: Not listed
• WADAWADA: Prohibited

Adipotide targets the blood vessels that supply white fat. It reversed obesity in mice [34] and caused weight loss with improved insulin resistance in obese monkeys. [35] We found no published human results. It has never been nominated for the bulks list, so no pharmacy may compound it.

Does hCG work for weight loss?

No. A criteria-based meta-analysis of hCG diet trials found no evidence that hCG improves weight loss, fat distribution, hunger, or well-being. [36] FDA states that hCG is not approved for weight loss and that over-the-counter hCG diet products are illegal. [37]

Are compounded weight loss peptides still legal?

For semaglutide and tirzepatide, only in narrow cases. FDA declared both shortages resolved, and the grace periods for routine compounding ended in 2025; a pharmacy may now compound them only for a documented patient-specific clinical need. [28] During the shortage, a study of online advertising found median first-month prices of 231 USD for compounded semaglutide and 330 USD for compounded tirzepatide. [38] The full story is in what happened to compounded semaglutide and the compounded tirzepatide guide. Items 7 to 14 on this list have no compounding path at all. State-by-state rules are on the peptide legality hub.

Are weight loss peptides safe?

For the approved drugs, the labels are the best guide. The most common side effects of tirzepatide and semaglutide are gastrointestinal, including nausea, diarrhea, vomiting, and constipation, and both carry a boxed warning about thyroid C-cell tumors seen in rodents. [3] [7] Our GLP-1 side effects ranking covers them in order of frequency. For the unapproved agents, safety is simply unknown outside trials: FDA warns that unapproved GLP-1 products sold online are not evaluated for safety, quality, or dose. [28]

The takeaway

The best peptides for weight loss, judged by human evidence, are the three approved GLP-1 drugs at the top of this list, and they are available by prescription. The newer triple and dual agonists look strong in trials but are not yet lawful to use outside them. Everything in the bottom tier is sold on mouse data. We will re-rank this list when an approval or a published human trial changes a grade.