Body Composition

A GLP-1 receptor agonist FDA-approved for type 2 diabetes and chronic weight management, one of the most widely prescribed peptide drugs.

A dual GIP/GLP-1 receptor agonist FDA-approved for diabetes and weight management, producing the largest weight loss seen in clinical trials.

Recombinant human growth hormone — the full 191-amino-acid pituitary peptide, FDA-approved for a short list of specific deficiency and wasting indications and the subject of an enormous off-label market for anti-aging, performance, and body-composition use that runs far ahead of the evidence.

A growth hormone-releasing hormone analog that was previously FDA-approved for diagnosing GH deficiency in children.

An FDA-approved GHRH analog used to reduce visceral fat in HIV-associated lipodystrophy.

A GLP-1 receptor agonist FDA-approved for diabetes (Victoza) and weight management (Saxenda), the predecessor to semaglutide.

A once-weekly GLP-1 receptor agonist FDA-approved for type 2 diabetes, with proven cardiovascular benefits and moderate weight loss effects.

The 167-amino-acid adipose hormone discovered in 1994 that was supposed to cure obesity — and did, for the handful of people born without it. For everyone else, the story turned out to be leptin resistance, not leptin deficiency, and the therapeutic lesson has been much harder than the biology.

The TGF-β superfamily protein that negatively regulates skeletal muscle mass — the biological target behind 'mighty mice,' Belgian Blue cattle, and an entire class of investigational inhibitor drugs that have underdelivered on the hype.

The circulating 'cellular stress' hormone of the TGF-β superfamily — the molecule that links metformin-induced weight loss, pregnancy-associated hyperemesis, and cancer cachexia through a single brainstem receptor (GFRAL). Not a self-administered peptide; the clinical programs are antibodies that block GDF-15, not supply it.

Foundayo (orforglipron) is Eli Lilly's oral small-molecule GLP-1 receptor agonist. Phase 3 trials show up to 11.2% weight loss via daily pill — no injections required. Regulatory submissions expected 2026.

An investigational dual glucagon/GLP-1 receptor agonist from Boehringer Ingelheim and Zealand Pharma. Phase 3 SYNCHRONIZE-1 (April 28, 2026 topline) achieved 16.6% mean weight loss at 76 weeks — the first positive Phase 3 readout in the SYNCHRONIZE obesity program. FDA Fast Track (2021) and Breakthrough Therapy (2024) designations for MASH; full SYNCHRONIZE-1 data at ADA June 2026.

Amgen's first-in-class once-monthly bispecific antibody-peptide conjugate for obesity — GLP-1 receptor agonist + GIP receptor antagonist. Phase 2 NEJM showed up to 21.6% weight loss at 52 weeks with no plateau.

An investigational triple agonist (GIP/GLP-1/glucagon) from Eli Lilly. Not FDA-approved. Phase III TRIUMPH-4 results showed 23.7% weight loss — the most of any obesity drug in development.

A long-acting amylin analogue being developed in combination with semaglutide (CagriSema) for enhanced weight loss.

Novo Nordisk's investigational unimolecular dual GLP-1 and amylin receptor agonist, advanced in both subcutaneous and oral formulations. Phase 1b/2a SC topline (Lancet 2025) showed up to 24.3% mean weight loss at 36 weeks — among the largest weight-loss signals reported for any single peptide, anywhere. Not approved by any regulator; Phase 2 obesity program underway.

The first GLP-1 receptor agonist, originally derived from Gila monster venom, FDA-approved for type 2 diabetes.

An FDA-approved synthetic analogue of amylin used alongside insulin for diabetes, also studied for weight management.

An FDA-approved MC4R agonist for rare monogenic obesity (POMC/PCSK1/LEPR deficiency, Bardet-Biedl syndrome) and — as of March 2026 — acquired hypothalamic obesity in patients aged 4 and older.

A naturally occurring peptide hormone that raises blood sugar, FDA-approved as emergency treatment for severe hypoglycemia.

The 244-amino-acid adipocyte-secreted hormone discovered independently by four groups in 1995–1996 — unusual among adipokines in that its levels fall with obesity, not rise with it. High-adiponectin states are protective; low-adiponectin states track insulin resistance, type 2 diabetes, and cardiovascular disease. Direct therapeutic use is limited by its large multimeric structure, and the field's forward push is toward small-molecule AdipoR agonists like AdipoRon.

A growth hormone-releasing hormone analog that stimulates the pituitary gland to produce more growth hormone.

An orally active growth hormone secretagogue that mimics ghrelin to stimulate GH and IGF-1 release.

A modified growth hormone releasing hormone analog with a shorter half-life than DAC-conjugated CJC-1295, allowing more physiological GH pulsing.

The active isomer of clomiphene, a selective estrogen receptor modulator (SERM) that raises testosterone while preserving fertility. Not FDA-approved as a standalone drug, but widely available through compounding pharmacies.

A triple monoamine reuptake inhibitor (serotonin, noradrenaline, dopamine) that produced up to 10.6% weight loss in Phase 2 trials — roughly double the efficacy of older appetite suppressants. Approved in Mexico; not yet FDA-approved.

The world's first approved dual GLP-1/glucagon receptor agonist, developed by Innovent Biologics (China). Approved in China for obesity and type 2 diabetes. Phase 3 trials showed up to 20.1% weight loss.

Zealand Pharma's long-acting amylin analog, partnered with Roche in a $5.3B deal. Phase 2b ZUPREME-1 showed 10.7% weight loss at 42 weeks with placebo-like tolerability — the 'tolerability play' in the amylin class.

Roche/Genentech's next-generation dual GLP-1/GIP receptor agonist (INN: enicepatide, assigned 2026). Phase 2 showed 22.5% placebo-adjusted weight loss at 48 weeks — competitive with retatrutide. Phase 3 ENITH program initiated Q1 2026 with two pivotal trials.

An endogenous 36-amino-acid gut hormone released by intestinal L-cells after meals; its active fragment PYY(3-36) is a Y2-receptor-selective satiety signal.

A selective growth hormone secretagogue that stimulates GH release without significantly affecting cortisol or prolactin.

A synthetic growth hormone secretagogue that stimulates natural GH release, studied for body composition, recovery, and anti-aging.

A synthetic growth hormone secretagogue known for potent GH release and significant appetite stimulation through ghrelin receptor activation.

A naturally occurring dipeptide concentrated in muscle and brain tissue, studied for anti-aging, cognitive support, and exercise performance.

The original 'exercise in a pill' — an AMPK activator that increased running endurance by 44% in sedentary mice. Banned by WADA since 2009. Studied for metabolic syndrome, diabetes, and cardioprotection.

An endogenous 37-amino-acid gut hormone and natural dual agonist at the GLP-1 and glucagon receptors — the physiologic template behind the dual-agonist obesity drug class (cotadutide, survodutide, mazdutide).

Acceleron Pharma's soluble ActRIIB-Fc decoy receptor — a myostatin/activin ligand trap that produced striking muscle-mass signals in healthy volunteers and Duchenne boys before its Phase 2 DMD program was halted in 2011 over epistaxis and telangiectasia attributed to broad TGF-β pathway blockade.

An endogenous peptide hormone and ligand of the APJ receptor with positive inotropic, vasodilatory, and insulin-sensitizing effects — heavily studied as a heart-failure target but not available as an approved therapy, with small-molecule APJ agonists now advancing through early clinical trials.

A modified fragment of human growth hormone studied specifically for fat metabolism without the growth-promoting effects of full GH.

An investigational once-weekly dual GLP-1/GIP receptor agonist from Jiangsu Hengrui, with ex-Greater China rights held by Kailera Therapeutics. Phase 3 in China produced up to 19.2% weight loss at 48 weeks; a global Phase 3 (KaiNETIC) began enrolling in January 2026.

Eli Lilly's once-weekly selective amylin receptor agonist. Phase 2 trials showed up to 20% weight loss at 48 weeks with favorable tolerability. Phase 3 enrollment began late 2025.

Pfizer's ultra-long-acting, fully-biased GLP-1 receptor agonist designed for once-monthly injection — with 12.3% placebo-adjusted weight loss at 28 weeks in Phase 2b and a 10-trial Phase 3 program planned.

A mitochondria-derived peptide that regulates metabolic homeostasis and has been called an 'exercise mimetic.'

An exercise-induced myokine that promotes browning of white adipose tissue, enhances metabolism, and shows neuroprotective effects — though bioavailability and clinical translation remain challenging.

A synthetic tetrapeptide bioregulator (Lys-Glu-Asp-Trp) from the Khavinson system, studied for pancreatic function, glucose metabolism, and age-related type 2 diabetes.

An experimental fat-targeting peptide that selectively destroys blood vessels feeding white adipose tissue. Produced dramatic fat loss in primate studies but was discontinued due to kidney toxicity.

A synthetic exercise mimetic that activates estrogen-related receptors (ERRs) to replicate the molecular effects of aerobic exercise — increasing endurance, fat oxidation, and mitochondrial function without physical activity.

A selective NNMT inhibitor that reduces fat mass by boosting NAD+ and cellular energy expenditure — without affecting appetite. In mice, 11 days of treatment produced 5% weight loss and 35% reduction in white adipose tissue.

A 14-amino-acid peptide hormone that activates galanin receptors 2 and 3 — lower in obesity and type 2 diabetes, investigated as a potential metabolic therapeutic and biomarker but still without any approved product or clinical trial program.

A 12-amino-acid peptide cleaved from the BRINP2 protein that activates hypothalamic POMC neurons via a non-incretin pathway. Identified by Stanford's Svensson lab using AI-driven prohormone-cleavage prediction and published in Nature (2025). Preclinical only — no human trials have been initiated as of April 2026.

The original synthetic growth hormone-releasing peptide developed by Cyril Bowers and Frank Momany in the late 1970s through structural optimization of Met-enkephalin — the historical seed of the GHRP class that gave rise to GHRP-2, GHRP-6, hexarelin, and ipamorelin, and the discovery program that eventually led to the identification of the ghrelin receptor (GHSR1a).

An endogenous TGF-β superfamily peptide closely related to myostatin (~90% identity in mature domain), launched into mainstream attention by Loffredo and Wagers' 2013 Cell paper claiming circulating GDF-11 declines with age and reverses cardiac hypertrophy in aged mice — a rejuvenation story that has been substantially complicated by Egerman, Glass, and others' contradicting work showing antibody specificity issues, GDF-11 increases (not decreases) with age in some populations, and direct GDF-11 administration may worsen rather than improve outcomes.

The N-terminal propeptide domain of myostatin that remains non-covalently bound to mature myostatin in latent extracellular complexes — characterized by Hill, Lee, and colleagues (JBC 2002, Mol Endocrinol 2003) as one of the principal endogenous inhibitors of myostatin signaling, alongside follistatin and the GASP-1/GASP-2 follistatin-related proteins. Studied as a research-tier myostatin antagonism strategy in muscular dystrophy, sarcopenia, and muscle-wasting models.