Peptides for Weight Loss Beyond GLP-1s

Semaglutide and tirzepatide changed what people believe a weight-loss medicine can do, and they did it as peptides. So it is natural to wonder what else is out there: newer combinations, pills, triple agonists, and the long list of "fat-loss peptides" sold online. Some of those are serious medicines with serious trials. Some are marketing wrapped around a mouse study.

If you are reading this, you may have tried a GLP-1 and stopped because of side effects or cost, hit a plateau, been told you are not a candidate, or simply want to know whether there is a gentler or "more natural" peptide option. Those are legitimate reasons to ask. This guide sorts the options by the quality of the evidence behind them, explains what is approved and what isn't, and describes how a clinician would think through the choice with you.

First, the benchmark: what GLP-1 peptides actually showed

Every other option on this page should be measured against the trials that made semaglutide and tirzepatide standard treatments.

In STEP 1, published in the New England Journal of Medicine in 2021, about 1,960 adults with overweight or obesity took weekly semaglutide 2.4 mg or placebo alongside lifestyle support for 68 weeks. Average weight change was roughly 15 percent with semaglutide versus about 2.4 percent with placebo.

In SURMOUNT-1, published in the same journal in 2022, tirzepatide — which acts on both GLP-1 and GIP receptors — was tested for 72 weeks. At the highest dose, average weight reduction was around 21 percent, compared with about 3 percent on placebo.

Those are large, long, placebo-controlled trials in thousands of people, with side effects carefully counted. They also showed the limits: gastrointestinal side effects are common, and when people in the STEP 1 extension stopped semaglutide, they regained about two-thirds of the weight they had lost within a year. For the full picture, read our complete GLP-1 guide and semaglutide vs tirzepatide.

Approved options beyond the weekly injection

Oral semaglutide for weight management

On December 22, 2025, FDA approved a once-daily oral semaglutide 25 mg tablet (sold as the Wegovy pill) for weight management. In the OASIS 4 trial that supported it, mean weight reduction was about 13.6 percent over 64 weeks. It is the same peptide as the injection, formulated to survive the gut, and for people who dislike injections it is a genuinely new option. Its labeling has specific instructions about how it is taken, which your prescriber will go through.

Orforglipron: a GLP-1 pill that isn't a peptide

On April 1, 2026, FDA approved orforglipron (Foundayo) for chronic weight management in adults with obesity, or overweight with at least one weight-related condition. It activates the GLP-1 receptor, but it is a small-molecule drug rather than a peptide, which is part of why it can be taken as a pill without food or water restrictions. It belongs in this conversation because it competes directly with peptide options, even though it is not one.

Setmelanotide: for specific diagnoses, not general weight loss

Setmelanotide (Imcivree) is an FDA-approved peptide that activates the MC4 receptor, part of the brain pathway that regulates hunger. It is approved for obesity caused by certain rare genetic conditions — POMC, PCSK1 or LEPR deficiency and Bardet-Biedl syndrome — and, since March 20, 2026, for acquired hypothalamic obesity, which can follow damage to the hypothalamus from tumors or their treatment. In the TRANSCEND trial behind that expansion, BMI fell by 18.4 percent more with setmelanotide than with placebo at one year.

If you have had severe, early-onset obesity with relentless hunger, or obesity that began after a brain tumor or its treatment, it is worth asking a specialist whether testing is appropriate. For most people with obesity, setmelanotide is not the right medicine, and it is not something to seek out as a general alternative.

Tesamorelin: approved, but for abdominal fat in a specific group

Tesamorelin (Egrifta) is an FDA-approved analogue of growth-hormone-releasing hormone. Its indication is narrow: reducing excess abdominal fat in adults with HIV-associated lipodystrophy. In a 26-week trial of 412 patients, visceral fat fell by about 15 percent with tesamorelin, compared with a small increase on placebo, and the effect was lost when treatment stopped. It was not developed or approved as a weight-loss drug, and evidence outside that population is much thinner. We cover it in tesamorelin: the approved GHRH analogue and its limits.

In late-stage development: promising, but not approved

CagriSema (cagrilintide plus semaglutide)

Amylin is a hormone released with insulin that also signals fullness. Cagrilintide is a long-acting amylin analogue, and CagriSema combines it with semaglutide in one weekly injection. In the REDEFINE 1 trial of 3,417 adults, published in the New England Journal of Medicine, average weight loss at 68 weeks was 20.4 percent with CagriSema versus 3.0 percent with placebo. In a later head-to-head trial, REDEFINE 4, reported in February 2026, CagriSema did not meet its primary goal of showing non-inferiority to tirzepatide.

Novo Nordisk filed for FDA approval in December 2025. As of our last check, no approval decision had been announced. Check current status before assuming it is available.

Retatrutide

Retatrutide is an investigational peptide that acts on three receptors: GLP-1, GIP and glucagon. In May 2026, Eli Lilly reported results from TRIUMPH-1, an 80-week phase 3 trial in 2,339 adults with obesity or overweight and at least one weight-related condition, excluding people with diabetes. At the highest dose, average weight loss was 28.3 percent, versus 2.2 percent on placebo. Those results were first announced by the company; full peer-reviewed data, longer-term safety and FDA review still matter. Retatrutide was not FDA-approved as of this writing.

The "fat-loss peptides" sold online: what the evidence says

This is the category most people mean when they search for peptides for weight loss. The pattern is consistent: a plausible mechanism, animal data, and little or no human evidence that the compound produces meaningful weight loss.

AOD-9604

AOD-9604 is a modified fragment of human growth hormone, developed as an obesity drug. It reduced weight gain in obese rats, and early human trials showed a small effect versus placebo. But development for obesity was halted in 2007 after a larger 24-week trial did not show the effect it needed. It is not FDA-approved. Its compounding status has been in flux, and it is named on the World Anti-Doping Agency's Prohibited List. The full story is in AOD-9604: the "fat-loss fragment" and what trials found.

MOTS-c

MOTS-c is a small peptide encoded in mitochondrial DNA. A 2015 study in Cell Metabolism by Lee and colleagues found that it acted on muscle metabolism and that treating mice with it prevented diet-induced obesity and insulin resistance. That is a striking finding in mice. We are not aware of published randomized trials showing that MOTS-c causes weight loss in people.

In July 2026 FDA's Pharmacy Compounding Advisory Committee narrowly recommended MOTS-c for the 503A bulk substances list, 7 votes to 5 with 2 abstentions, after FDA's own reviewers concluded it did not meet the criteria. The vote is non-binding, rulemaking would be required, and it could not lawfully be compounded from bulk as of this writing. MOTS-c is also named on WADA's 2026 Prohibited List as a metabolic modulator. See MOTS-c: the mitochondrial peptide.

Growth-hormone secretagogues: CJC-1295, ipamorelin, sermorelin

These compounds are designed to increase the body's own growth hormone release. The reasoning behind using them for fat loss is that growth hormone encourages fat breakdown, so more of it should mean less fat. Growth hormone does affect fat metabolism. But the leap from "affects fat metabolism" to "produces clinically meaningful, durable weight loss with acceptable safety" is exactly the leap that has to be demonstrated in trials, and for these compounds it has not been.

There are also trade-offs that get left out of the sales pitch: effects on blood sugar and insulin sensitivity, fluid retention and joint symptoms, and the fact that raising growth hormone activity is not automatically desirable. Sermorelin was once FDA-approved in the US as Geref; its maker stopped selling it, and FDA determined in 2013 that it had not been withdrawn for reasons of safety or effectiveness. The legal status of these compounds has been in flux, so ask a clinician where each one stands today. Our explainers cover CJC-1295 and ipamorelin and sermorelin.

What about BPC-157, TB-500 and the rest?

They are marketed for healing and recovery rather than weight loss, and there is no good human evidence that they change body weight. If a clinic bundles them into a weight-loss package, that tells you something about the clinic. See why peptide stacks are a red flag and BPC-157 in 2026.

The options side by side

A word on compounded versions

During the shortages of semaglutide and tirzepatide, compounded versions became widely available. FDA later announced that those shortages had been resolved, which changed the legal footing for making copies of approved drugs, and it has warned about problems with some compounded and counterfeit products. Compounded preparations are not FDA-approved, and the details of what is permitted have shifted more than once. Verify the current position with FDA or your prescriber, and read compounded GLP-1s: what to know.

How a clinician chooses between these options

The right question is rarely "which peptide?" It is "what is driving the weight, what has been tried, and what does the evidence support for this person?" A careful assessment usually covers:

• Medical history and red flags for medicines that are not appropriate, including personal or family history of medullary thyroid cancer, pancreatitis, gallbladder disease, pregnancy or plans for it, and eating disorders.
• Other contributors: thyroid function, sleep and possible sleep apnea, medicines that promote weight gain, blood sugar and insulin resistance, and hormonal changes such as perimenopause or low testosterone.
• Baseline labs that make sense for you. See lab work before peptide therapy.
• What you have tried and why it stopped working: side effects, cost, access, plateau or regain. Each points to a different next step.
• Your current medicines, especially insulin, sulfonylureas and oral contraceptives. See combining peptides with TRT or GLP-1s.
• A plan for muscle and maintenance, because weight loss includes lean mass and stopping treatment often leads to regain.

Some people are not candidates for any of the approved medicines; our guide to who should not take a GLP-1 explains why. That doesn't make an unapproved peptide the fallback. It usually means a different plan.

Muscle, plateaus and the long game

Much of the demand for "extra" peptides comes from three real frustrations with GLP-1 treatment.

Losing muscle. Significant weight loss includes some lean mass. The measures with real evidence are adequate protein and resistance training; there is no good human evidence that growth-hormone-releasing peptides or MOTS-c protect muscle during GLP-1 treatment. Our guide to muscle loss on GLP-1s explains what to do.

Hitting a plateau. Weight loss slows and stops for everyone at some point, because the body adapts. A plateau is a reason to review dose, adherence, sleep, activity and expectations, and sometimes to consider a different approved medicine, not to add an unproven one. See the weight-loss plateau.

Appetite coming back. For many people "food noise" returns when treatment stops. That reflects obesity being a chronic condition. See food noise, explained, and what happens when you stop a GLP-1.

Cost, access and athletes

Price is one of the most common reasons people look beyond approved medicines. It is also where unapproved options can look deceptively cheap: the vial price leaves out labs, follow-up, and the cost of something going wrong without anyone accountable. Ask for the full cost of care before you commit. Our line-by-line cost breakdown shows what to ask about, and HSA and FSA for telehealth covers paying for care.

If you compete in tested sport, check every compound with your anti-doping organization. AOD-9604 and MOTS-c are both named on WADA's 2026 Prohibited List. See peptides and drug testing.

How we approach weight-loss consultations

When someone asks us about peptides for weight loss, we start with the question underneath: what has happened so far, what is getting in the way, and what you want your health to look like in two years rather than two months. From there we rank the options the way this article does: approved medicines with strong trials first, then honest conversation about what is investigational, and plain answers about what is not lawfully available or not supported by human evidence.

A consultation with us may conclude that an approved medicine is a good fit, that treating your sleep apnea or reviewing a medicine you already take should come first, or that nothing on the peptide list is appropriate for you. No consultation ends with a guaranteed prescription. You can read about our peptide therapy consultations, see what the visit involves, or book a consultation when you are ready.

Common questions

What is the best peptide for weight loss?

The peptides with the strongest human evidence for weight management are the FDA-approved ones: semaglutide and tirzepatide. Which, if either, suits you depends on your history, other medicines, side effects and cost. The peptides marketed online as fat-loss alternatives lack comparable evidence.

Is there a peptide that works like Ozempic without the side effects?

No peptide has been shown in good trials to deliver comparable weight loss with fewer side effects. Some people tolerate one approved medicine better than another, and dose pacing can help. That is a conversation to have with a prescriber.

Is retatrutide available?

Not as an approved medicine as of this writing. It has reported phase 3 results, but it has not been approved by FDA. Products sold online as retatrutide are not pharmacy-made medicines.

Do AOD-9604 or MOTS-c help with fat loss?

AOD-9604's obesity development was halted in 2007 after a disappointing 24-week trial. MOTS-c prevented diet-induced obesity in mice, but we are not aware of adequate human weight-loss trials. Neither is FDA-approved.

Can I get a weight-loss peptide without trying a GLP-1?

Your clinician will consider what fits your situation, which may or may not be a GLP-1. What we won't do is substitute an unapproved peptide for an approved medicine simply because it sounds gentler. If a GLP-1 isn't right for you, there are other approaches to discuss.