Research Peptides Directory

Retatrutide is an investigational triple-action weight loss peptide that targets three metabolic pathways at once. In clinical trials, it's produced the strongest weight loss results ever seen from a drug — nearly 29% body weight reduction.

Semaglutide is a GLP-1 weight loss drug (brand names Wegovy and Ozempic) that helps reduce appetite and control blood sugar. It's FDA-approved and is one of the most prescribed obesity medications worldwide.

Tirzepatide is a dual-action weight loss drug (brand names Zepbound and Mounjaro) that targets two hormone receptors to reduce appetite and improve blood sugar. It's FDA-approved and delivers stronger weight loss than semaglutide.

Liraglutide is an FDA-approved GLP-1 weight loss and diabetes drug (brand names Saxenda and Victoza) that helps reduce appetite and control blood sugar with a daily injection.

Cagrilintide is a weekly injection being developed for weight loss. It copies amylin, a hormone your pancreas naturally releases after eating to tell your brain you are full. By boosting that fullness signal and slowing how fast the stomach empties, it helps people eat less without feeling deprived. On its own it produced around 10 percent weight loss in mid-stage studies. Paired with semaglutide in a combination called CagriSema, it reached about 20 percent body-weight loss over roughly 16 months in large late-stage trials, with most side effects being temporary stomach-related issues like nausea. It is made by Novo Nordisk, is still investigational, and is under review by regulators rather than approved for sale.

5-Amino-1MQ is a small molecule that may boost metabolism and promote fat burning by blocking an enzyme called NNMT. It's being studied as a potential treatment for obesity and metabolic disorders.

HGH Fragment 176-191 is a fat-burning peptide derived from human growth hormone that targets body fat without the other effects of full HGH. It's essentially the fat-loss portion of growth hormone isolated on its own.

Setmelanotide, sold as Imcivree, is an FDA-approved peptide medicine given as a daily injection under the skin. It works by switching on MC4R, a receptor in the brain that controls the feeling of fullness. The important thing to understand is who it is for: it is approved for people with specific rare conditions (POMC, PCSK1, or LEPR deficiency, Bardet-Biedl syndrome, and acquired hypothalamic obesity) in which the brain's hunger-control pathway is broken or damaged, causing extreme hunger and severe obesity. In those groups, trials showed most patients lost significant weight and felt far less hungry over about a year. It is not approved as a general weight-loss drug, and it has not been shown to work the same way in people whose hunger pathway is normal. The most common and expected side effect is a darkening of the skin and moles, because the receptor it targets also affects skin pigment, along with injection-site reactions and nausea.

Tesofensine is an experimental weight-loss pill. It works in the brain by keeping three appetite-related chemicals, noradrenaline, dopamine, and serotonin, active for longer, which strengthens the feeling of fullness and reduces hunger. That is a different approach from the popular injections like semaglutide, which act through a gut hormone. In a 24-week Phase 2 trial of people with obesity, the 0.5 mg dose led to about 9 percent body-weight loss, roughly double what the diet drugs of that era achieved, and the 1.0 mg dose reached about 11 percent. The main drawbacks are a faster heart rate and disturbed sleep, which is why a newer version pairs it with a low dose of a heart-slowing medicine. Tesofensine is taken once a day by mouth, is still investigational, and is not approved for sale.

AOD-9604 is a fat-burning peptide derived from human growth hormone that may help reduce body fat without affecting blood sugar or muscle mass. It targets fat cells specifically.

SLU-PP-332 is an experimental compound nicknamed an "exercise mimetic." It chemically switches on a set of cell controls called ERRs that the body normally activates during aerobic exercise, which turns up the genes for mitochondria (the cell's power plants) and fat burning. In mice, this reproduced several benefits of exercise: more fat burned, less fat mass, better insulin sensitivity, and improved endurance. The important caution is that all of this is animal research. SLU-PP-332 has never been tested in humans, so there is no established human dose and no human safety data. It is also poorly absorbed when swallowed, which is why a newer compound was designed to replace it, so the oral capsules sold to people may not deliver a reliable amount. It is a small-molecule research chemical, not a peptide, and it is not approved for human use.