Peptide List A–Z

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.

The 51-amino-acid two-chain pancreatic hormone discovered by Banting, Best, Macleod, and Collip at the University of Toronto in 1921-22 — the first life-saving peptide drug, the molecule whose primary structure Frederick Sanger determined in 1955 (the first protein ever sequenced), and the cornerstone of type 1 diabetes management plus advanced type 2 diabetes care for over a century.

An investigational triple agonist (GIP/GLP-1/glucagon) from Eli Lilly. Not FDA-approved. In Phase III TRIUMPH-1 (NEJM, September 2026) the 12 mg dose produced 25.0% mean weight loss at 80 weeks, and TRIUMPH-2 (Lancet, September 2026) showed up to 18.8% in adults with obesity and type 2 diabetes. Lilly plans to file with the FDA in Q1 2027.

A naturally occurring neuropeptide involved in social bonding, trust, and reproduction, FDA-approved for labor induction.

An investigational dual glucagon/GLP-1 receptor agonist from Boehringer Ingelheim and Zealand Pharma. The Phase 3 SYNCHRONIZE-1 trial (le Roux et al., NEJM 7 June 2026) demonstrated ~12–13% mean weight loss at 76 weeks (treatment-regimen estimand) in adults with obesity without type 2 diabetes, and the companion SYNCHRONIZE-MASLD trial (Kaplan/Sanyal et al., Nature Medicine, same date) showed 84.2% of participants reduced liver fat by ≥30% at 48 weeks. SYNCHRONIZE-2 (Wharton et al., NEJM 1 October 2026) then showed -8.2% (3.6 mg) and -9.8% (6.0 mg) vs -3.9% placebo at 76 weeks in adults with obesity and type 2 diabetes (treatment-regimen estimand; up to 13.1% vs 3.1% on the efficacy estimand). FDA Fast Track (2021) and Breakthrough Therapy (2024) designations for MASH; not yet approved.

A 165-amino-acid glycoprotein hormone produced by the kidney that drives red blood cell production. FDA-approved as recombinant human EPO and longer-acting analogs for anemia of chronic kidney disease, chemotherapy, and HIV — and infamous as an endurance-sports doping agent prohibited at all times by WADA.

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

An FDA-approved melanocortin receptor agonist for hypoactive sexual desire disorder in premenopausal women, also studied for broader sexual dysfunction.

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

A once-weekly amylin analogue from Novo Nordisk, developed with semaglutide as CagriSema (US decision expected Q4 2026) and, since late 2025, on its own in Phase 3.

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

Foundayo (orforglipron) is Eli Lilly's oral small-molecule GLP-1 receptor agonist — FDA-approved April 1, 2026 for chronic weight management as the first oral non-peptide GLP-1 RA. Approved via the Commissioner's National Priority Voucher pilot in 50 days, the fastest NME approval since 2002. Once-daily tablet titrated 0.8 mg → 17.2 mg max; Phase 3 ATTAIN-1 showed 11.2% weight loss at 72 weeks.

The 146-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.

Novo Nordisk's unimolecular dual GLP-1 and amylin receptor agonist (INN zenagamtide), 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. Phase 2 T2D peer-reviewed publications landed in Lancet August 15, 2026 (Mora et al., separate SC and oral papers): once-weekly SC (n=262) HbA1c treatment difference −0.77% to −1.56% and once-daily oral (n=186) HbA1c treatment difference −0.5% to −1.09% vs placebo at 36 weeks. The AMAZE Phase 3 program initiated in 2026 — AMAZE-1 (NCT07339423, 1,150 pts) started February 24, 2026 and AMAZE-12 (NCT07503210, ~600 pts, obesity maintenance) on April 21, 2026, with additional AMAZE trials in obesity+T2D, obesity+OA, and head-to-head versus semaglutide.

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

Synthetic gonadotropin-releasing hormone used diagnostically and therapeutically for reproductive hormone assessment and fertility.

Amgen's first-in-class once-monthly bispecific antibody-peptide conjugate for obesity — GLP-1 receptor agonist + GIP receptor antagonist. Phase 2 NEJM showed mean weight loss of up to 16.2% at 52 weeks by intention-to-treat, or up to 19.9% if participants stayed on treatment, with no plateau.

The endogenous 28-amino-acid 'hunger hormone' from the stomach — the natural ligand of GHS-R1a, the receptor that GHRP-2, GHRP-6, hexarelin, ipamorelin, and MK-677 all target. A research peptide and pharmacology reference, not a self-administered compound.

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 endogenous 13-amino-acid melanocortin hormone cleaved from POMC. Parent molecule for the melanotan / setmelanotide / KPV cluster — acts at MC1R (pigmentation), MC3R/MC4R (appetite, energy balance), and MC5R, with well-characterized anti-inflammatory activity.

An endogenous gut-and-brain peptide hormone released by intestinal I-cells that triggers gallbladder contraction, pancreatic enzyme secretion, and meal-ending satiety via vagal CCK-1 receptors.

An FDA-approved 14-amino-acid oral peptide that activates intestinal guanylate cyclase-C to treat chronic idiopathic constipation in adults, IBS-C in adults and children 7 and older, and functional constipation in children 2 and older.

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.

The endogenous 8-amino-acid effector peptide of the renin-angiotensin-aldosterone system (RAAS) — the body's master vasoconstrictor and aldosterone-release signal, and, as synthetic Giapreza, an FDA-approved IV infusion for catecholamine-resistant vasodilatory shock.

A PEGylated cyclic peptide derived from compstatin that binds and inhibits complement component C3 — FDA-approved as Empaveli for paroxysmal nocturnal hemoglobinuria (2021) and C3 glomerulopathy / immune-complex MPGN (2025), and as Syfovre for geographic atrophy secondary to age-related macular degeneration (2023).

The first oral peptide that blocks the interleukin-23 (IL-23) receptor. Discovered by Protagonist Therapeutics and Johnson & Johnson, it was approved by the FDA in March 2026 as Icotyde, a once-daily 200 mg pill for moderate-to-severe plaque psoriasis in adults and in children 12 and older who weigh at least 40 kg. It beat the oral psoriasis drug deucravacitinib in two head-to-head Phase 3 trials and is in Phase 3 for psoriatic arthritis, ulcerative colitis and Crohn's disease.

A long-acting vasopressin prodrug used to squeeze the splanchnic circulation in advanced liver disease. It is the first and only FDA-approved drug for hepatorenal syndrome, and standard first-line therapy for bleeding oesophageal varices across Europe and Asia — but it carries a boxed warning for serious or fatal respiratory failure, and the FDA and European regulators drew noticeably different conclusions from the same pivotal trial.

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

Precursors to NAD+, a critical coenzyme for cellular energy and longevity pathways. NAD+ levels decline with age.

The most-studied copper peptide in skincare — a naturally occurring tripeptide (GHK, Gly-His-Lys) whose active tissue form is the copper complex GHK-Cu, with extensive evidence for skin remodeling, collagen synthesis, wound healing, and anti-aging.

The body's most abundant antioxidant — a tripeptide critical for detoxification, immune function, and cellular protection, and one of the most widely used systemic skin-brightening and hyperpigmentation interventions via oral, IV, SubQ/IM, and topical routes (note: IV use for skin lightening is FDA-flagged and not approved).

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.

A cosmetic peptide that reduces wrinkles by inhibiting neurotransmitter release at the neuromuscular junction, often called 'topical Botox.'

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.

The hepatic peptide hormone of fasting and ketogenic states — and the target behind the most exciting current NASH/MASH pipeline. Native FGF21 has a half-life measured in hours; the clinical drugs are engineered Fc-fusions and PEGylated variants dosed weekly.

Placental glycoprotein hormone that acts as an LH-receptor agonist — used clinically as an ovulation trigger in IVF and off-label in men to stimulate endogenous testosterone and preserve fertility during or after exogenous androgen use.

Viking Therapeutics' dual GLP-1/GIP receptor agonist in late-stage development for obesity, available in subcutaneous weekly (Phase 3) and oral daily (Phase 2) formulations — positioned as a direct competitor to tirzepatide. A September 2026 maintenance study found that every-other-week or monthly dosing kept up to 97% and 90% of the weight lost on weekly induction, versus 61% on placebo.

A porcine brain-derived peptide preparation with neurotrophic properties, approved in several countries for stroke recovery and cognitive disorders.

A potent growth hormone secretagogue peptide that also has cardioprotective properties independent of GH release.

A biased-agonist GLP-1 receptor agonist from Sciwind Biosciences, engineered to favor Gs/cAMP signaling over β-arrestin recruitment. Phase 3 data in overweight/obese adults showed ~13.2% body weight reduction at 40 weeks, and the EECOH-1 and EECOH-2 Phase 3 diabetes trials established monotherapy efficacy versus placebo and non-inferiority versus dulaglutide. Approved by China's NMPA for both type 2 diabetes (Jan 2026) and long-term weight management (Mar 2026); not FDA-approved.

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 urine-derived gonadotropin preparation containing both FSH and LH activity, used for ovulation induction and controlled ovarian stimulation in IVF — the original injectable fertility drug, still in use as Menopur and HP-hMG formulations.

Merck's oral macrocyclic peptide PCSK9 inhibitor, marketed as Lipfendra — the first oral PCSK9 inhibitor ever approved, cleared by the FDA on July 16, 2026 after the CORALreef Phase 3 programme. One 20 mg tablet daily, taken on an empty stomach, lowers LDL-C by roughly 55 to 60 percent — comparable to the injectable antibodies evolocumab and alirocumab, without the injection.

A thymic peptide approved in multiple countries for immune modulation, particularly in hepatitis and as a vaccine adjuvant.

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

An FDA-approved fragment of parathyroid hormone that stimulates new bone formation, used for severe osteoporosis.

An FDA-approved GnRH agonist used for prostate cancer, endometriosis, and precocious puberty through hormonal suppression.

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

A triple monoamine reuptake inhibitor (serotonin, noradrenaline, dopamine) that produced 9.2% average weight loss at 0.5 mg (vs 2.0% on placebo, both with diet) in a 24-week Phase 2 Lancet trial, and 10.6% at 1 mg. Not approved in any country, including Mexico.

The world's first approved dual GLP-1/glucagon receptor agonist, developed by Innovent Biologics (China) with Eli Lilly holding ex-China rights. Approved in China for obesity and type 2 diabetes. The Phase 3 GLORY-2 trial (JAMA 2026) reported 16.7% mean weight loss at 9 mg over 60 weeks; a US Phase 2 trial reported up to 18.1% at 16 mg over 32 weeks.

Zealand Pharma's long-acting amylin analog, partnered with Roche in a $5.3B deal. Phase 2b ZUPREME-1 showed up to 10.7% weight loss at 42 weeks with placebo-like GI tolerability apart from mild titration nausea — the 'tolerability play' in the amylin class. Phase 3 ZUPREME began September 2026.

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. A 48-week Phase 2 in type 2 diabetes (September 2026) showed HbA1c down 2.65 points and 15.5% weight loss at 24 mg.

The first FDA-approved mitochondria-targeted peptide. Stealth BioTherapeutics received accelerated approval on September 19, 2025 to improve muscle strength in Barth syndrome — an ultra-rare X-linked cardiolipin disorder whose entire known global population numbers around 500 — marketed as Forzinity.

A modified C-type natriuretic peptide analog developed by BioMarin Pharmaceutical, FDA-approved as Voxzogo for children with achondroplasia. The first targeted pharmacological treatment for the most common form of genetic short stature.

An FDA-approved synthetic analog of parathyroid hormone-related protein (PTHrP 1-34) used to stimulate new bone formation in postmenopausal women at high risk of fracture.

The endogenous nine-amino-acid posterior-pituitary hormone that regulates water balance, vascular tone, and the stress axis — FDA-approved, as Vasostrict, only to raise blood pressure in adults with vasodilatory shock who stay hypotensive despite fluids and catecholamines.

The endogenous cyclic neuropeptide (SST-14 and SST-28 isoforms) that acts as the body's universal inhibitor of hormone and exocrine secretion — the physiological parent of the approved analogs octreotide, lanreotide, and pasireotide.

The native hypothalamic decapeptide that sits at the top of the reproductive axis, releasing LH and FSH in pulses to drive gonadal steroidogenesis.

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 36-amino-acid endogenous neuropeptide, one of the most abundant in the mammalian brain and the central nervous system's primary orexigenic (hunger-driving) signal.

An 11-amino-acid endogenous tachykinin neuropeptide encoded by the TAC1 gene that acts primarily at the neurokinin-1 (NK1) receptor — the first identified peptide neurotransmitter and a central mediator of pain transmission, neurogenic inflammation, and the vomiting reflex.

The 31-amino-acid endogenous opioid peptide cleaved from POMC in the pituitary and hypothalamus. The canonical 'endorphin' of popular science — invoked to explain runner's high, placebo analgesia, and acupuncture — though modern evidence has substantially weakened the classical runner's-high story.

A 27-amino-acid peptide hormone produced by S cells of the duodenal mucosa — historically the first hormone ever identified (Bayliss & Starling, 1902, who coined the word 'hormone' to describe it). Secretin stimulates pancreatic bicarbonate-rich fluid secretion, modulates gastric acid via somatostatin, and is FDA-approved as a synthetic diagnostic reagent (ChiRhoStim) for pancreatic-function testing, gastrinoma evaluation, and identification of the ampulla of Vater during ERCP. Secretin-enhanced MRCP is widely practiced but off-label — no secretin product carries an MRI or MRCP indication.

A GLP-1 receptor antagonist derived from the C-terminal fragment of exendin-4, investigational for post-bariatric hypoglycemia and congenital hyperinsulinism — pharmacologically the opposite of semaglutide and exenatide. The Phase 3 LUCIDITY trial met its primary endpoint on 18 August 2026 with a 55% reduction in Level 2 and Level 3 hypoglycemic events (p=0.000003), making avexitide the first GLP-1 receptor antagonist to succeed in Phase 3; Amylyx plans an NDA by the end of 2026.

Altimmune's investigational unimolecular GLP-1 / glucagon receptor dual agonist peptide with what Altimmune describes as a balanced 1:1 receptor activity ratio — among the most glucagon-weighted dual agonists in clinical development for MASH. The Phase 2b IMPACT trial (n=212, biopsy-confirmed MASH F2/F3) reported MASH resolution rates of 58% (1.2 mg) and 52% (1.8 mg) versus 20% on placebo at 24 weeks (Lancet 2025), with 48-week non-invasive endpoints presented at EASL 2026 (Barcelona, May 27–30): ELF down 0.58, liver stiffness −3.97 kPa, MRI liver fat content −54.7%, and weight loss 7.5% at the 1.8 mg dose. The 48-week abstract received the Best of EASL 2026 designation, and a separate EASL late-breaking poster reported qFibrosis-measured fibrosis regression at 24 weeks (68.6%/54.5%/29.6% across 1.2 mg/1.8 mg/placebo) — closing a notable gap with the negative 24-week NASH-CRN biopsy fibrosis endpoint. FDA Fast Track and Breakthrough Therapy (January 2026) designations for MASH. The Phase 3 PERFORMA trial (NCT07795164, ~1,800 patients) began in July 2026, and the Phase 2 RECLAIM trial in alcohol use disorder read out positive in July 2026.

Ascendis Pharma's once-weekly TransCon prodrug of human growth hormone, FDA-approved as SKYTROFA in August 2021 for pediatric growth hormone deficiency and expanded to adult GHD in July 2025. It releases unmodified somatropin from an inert carrier across a week, replacing seven daily injections with one — and in its pivotal pediatric trial it beat daily somatropin on growth, not merely matched it.

Gan & Lee's GLP-1 receptor agonist built for one injection every two weeks. In China's Phase 3 GRADUAL-1 trial, weight fell 15.12% (24 mg) and 18.54% (48 mg) over 52 weeks vs 1.11% on placebo; China's regulator accepted its marketing application in September 2026 and Menarini holds European rights. It is not approved anywhere yet.

Hanmi's once-weekly GLP-1 receptor agonist, an exendin-4 analog linked to an antibody Fc fragment. Under Sanofi it cut major cardiovascular events by 27% in the 4,076-person AMPLITUDE-O trial; back with Hanmi, it was approved in South Korea on 7 October 2026 as EPPE — the country's 45th domestically developed new drug and its first home-grown GLP-1 for obesity.

An FDA-approved GnRH agonist decapeptide delivered as a biodegradable implant under the abdominal skin — used for prostate cancer, premenopausal breast cancer, endometriosis, and endometrial thinning, and the only GnRH analogue given as a solid rod rather than an injection.

The only FDA-approved recombinant human IGF-1 — a 70-amino-acid protein identical to the body's own IGF-1, approved for severe primary IGF-1 deficiency in children, and the regulated counterpart to the IGF-1 analogues sold as research chemicals.

The only growth hormone receptor blocker ever approved — a re-engineered growth hormone molecule that occupies its own receptor without switching it on, used daily in acromegaly to force IGF-1 back into the normal range when surgery and somatostatin analogues have failed.

A 16-amino-acid copy of the gut hormone uroguanylin, changed at a single position, taken as a once-daily tablet for chronic constipation and constipation-predominant IBS — it works entirely inside the intestine and is never measurable in blood.

A 15-amino-acid macrocyclic peptide that blocks complement C5 and is injected under the skin once a day — the first self-administered complement inhibitor for myasthenia gravis. It was found by mRNA display using amino acids that do not exist in nature, and it reaches patients whose antibodies against the same target do not work.

A radioactive prostate cancer drug that carries lutetium-177 to PSMA-expressing tumour cells and irradiates them from the inside. Approved by the FDA in March 2022 as the first PSMA-targeted radioligand therapy, it is given as six infusions six weeks apart after a PSMA PET scan confirms the target. Distinct from the somatostatin-targeted Lutathera — same radionuclide, completely different homing molecule and completely different cancer.

An FDA-approved selective MC1R agonist for erythropoietic protoporphyria (EPP). Stimulates protective eumelanin production without the broad side effects of Melanotan II.

An FDA-approved peptide hormone used to treat osteoporosis and Paget's disease by inhibiting bone resorption.

A synthetic analogue of vasopressin (ADH) FDA-approved for diabetes insipidus, bedwetting, and bleeding disorders.

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.

An FDA-approved somatostatin analogue used to treat acromegaly, carcinoid tumors, and severe diarrhea.

An FDA-approved immunomodulatory peptide mixture for relapsing-remitting multiple sclerosis (MS).

An FDA-approved GnRH agonist for advanced prostate cancer and central precocious puberty, used outside the US for endometriosis, IVF, and breast cancer ovarian suppression, and discussed in bodybuilding circles as an unproven post-cycle 'restart'.

The pituitary hormone that tells the adrenal gland to make cortisol — available as the synthetic 1-24 fragment (cosyntropin) for adrenal testing and as a long-acting gel (Acthar) for a handful of inflammatory indications.

The endogenous 33-amino-acid intestinotrophic hormone co-released with GLP-1 from intestinal L-cells — the physiological template behind the FDA-approved short bowel syndrome drug teduglutide.

An FDA-approved long-acting somatostatin analog used to treat acromegaly, gastroenteropancreatic neuroendocrine tumors, and carcinoid syndrome.

An FDA-approved GnRH receptor antagonist decapeptide used for advanced prostate cancer — suppresses testosterone within days with no initial flare, in contrast to GnRH agonists like leuprolide and triptorelin.

A 132-amino-acid endogenous neuropeptide (cleaved before secretion to the 50-residue C-terminal active fragment, AgRP(83-132)) expressed almost exclusively in a discrete population of arcuate-nucleus neurons. Acts as an inverse agonist and competitive antagonist at MC3R and MC4R — the counter-regulatory signal to α-MSH in the leptin–melanocortin appetite circuit and the defining 'hunger neuron' marker.

An FDA-approved synthetic prostaglandin E1 (PGE1) — a 20-carbon eicosanoid lipid, not a peptide — used as an intracavernosal injection, urethral suppository, or topical cream for erectile dysfunction, and as an intravenous infusion in neonates to maintain ductus arteriosus patency in ductus-dependent congenital heart disease.

FDA-approved erythroid maturation agent — a modified ActRIIB-IgG1-Fc ligand trap that binds GDF11, activin B, and related TGF-β superfamily ligands to relieve Smad2/3-driven block on late-stage erythropoiesis. Approved for transfusion-dependent β-thalassemia (BELIEVE) and lower-risk myelodysplastic syndromes (MEDALIST, COMMANDS).

FDA-approved (March 2024) first-in-class activin signaling inhibitor for pulmonary arterial hypertension — a recombinant ActRIIA-IgG1-Fc fusion that traps activin A and related TGF-β superfamily ligands to rebalance pro-proliferative and anti-proliferative signaling in the pulmonary vasculature. Pivotal evidence: PULSAR (NEJM 2021), STELLAR (NEJM 2023), ZENITH and HYPERION (NEJM 2025).

Orally active ghrelin receptor agonist, FDA-approved in 2017 as a single-dose diagnostic for adult growth hormone deficiency — not a treatment.

An endogenous 29-amino-acid (30 in humans) neuropeptide discovered in 1983 by Tatemoto, signaling through three G-protein-coupled receptor subtypes (GAL1, GAL2, GAL3) and modulating feeding, mood, nociception, seizure activity, and basal-forebrain cholinergic neurodegeneration in Alzheimer's disease.

An endogenous 21-amino-acid peptide produced by vascular endothelial cells, isolated and sequenced in 1988 by Masashi Yanagisawa and colleagues at Tsukuba — the most potent vasoconstrictor known in mammalian biology, signaling through ETA and ETB G-protein-coupled receptors and the molecular target of the FDA-approved endothelin receptor antagonist (ERA) drug class used to treat pulmonary arterial hypertension and resistant hypertension.

A family of endogenous opioid peptides derived from the prodynorphin (PDYN) gene that are selective agonists at the kappa-opioid receptor (KOR), best known as the dysphoric, aversive, stress-induced counterpart to the euphoric mu-receptor-preferring beta-endorphin system, and the target of the KOR-antagonist antidepressant programs — aticaprant and navacaprant — both of which failed Phase 3 trials for major depression and were discontinued in 2025 and 2026.

An endogenous 13-amino-acid neuropeptide isolated from bovine hypothalamus by Robert Carraway and Susan Leeman in 1973, signaling through three receptors (NTS1, NTS2, and the sortilin/NTS3 sorting receptor) and modulating dopaminergic transmission, gastrointestinal motility, thermoregulation, blood pressure, and analgesia — with major translational interest in NTS1 agonists for schizophrenia and NTS1-targeted radioligand therapy in cancer.

A 22-amino-acid gut hormone produced by M cells of the proximal small-intestinal mucosa, isolated and named by John Christopher Brown's group in Vancouver between 1966 and 1971, signaling through a single G-protein-coupled receptor (MLNR/GPR38) to drive the gastric phase III of the migrating motor complex during fasting.

An endogenous peptide hormone discovered functionally by John Edkins in 1905 and structurally solved by Roderic Gregory and Hilda Tracy at Liverpool in 1964. Produced by G cells of the gastric antrum and duodenum, secreted in two principal molecular forms (G17 and G34) sharing the C-terminal Trp-Met-Asp-Phe-NH2 pharmacophore with cholecystokinin, and acting at the CCK-2/CCK-B receptor to drive parietal-cell acid secretion via ECL-cell histamine release and to exert trophic effects on the oxyntic mucosa.

An endogenous 7-amino-acid peptide (Asp-Arg-Val-Tyr-Ile-His-Pro) generated principally from angiotensin II by ACE2, acting at the Mas receptor as the counter-regulatory arm of the renin-angiotensin-aldosterone system — opposing angiotensin II's vasoconstriction, fibrosis, and pressor effects with vasodilatory, anti-fibrotic, and cardioprotective signaling.

A 36-amino-acid hormone of the PP-fold family produced by the F-cells (PP-cells) of the pancreatic islets, first isolated as the avian form from chicken pancreas by James Kimmel and colleagues in 1975, with the mammalian homologues following, and characterized as a postprandial vagally-mediated anorectic hormone that signals preferentially through the Y4 receptor — together with peptide YY and neuropeptide Y, it forms the canonical PP-fold/NPY family of feeding-related peptides.

A 47-amino-acid N-myristoylated lipopeptide and first-in-class NTCP entry inhibitor — FDA-approved on May 22, 2026 as Hepcludex (bulevirtide-gmod) for adults with chronic hepatitis delta virus (HDV) infection without cirrhosis or with compensated cirrhosis. The first US-approved therapy for HDV, the most severe form of viral hepatitis. Previously EMA-approved since July 2020 and marketed in Europe by Gilead Sciences.

Ascendis Pharma's once-weekly TransCon prodrug of C-type natriuretic peptide, FDA-approved under accelerated approval on 27 February 2026 as YUVIWEL to increase linear growth in children aged 2 and older with achondroplasia and open epiphyses. The second CNP-pathway therapeutic ever approved, and the first that is dosed weekly rather than daily.

Ascendis Pharma's TransCon prodrug of parathyroid hormone (PTH 1-34), FDA-approved as YORVIPATH on 9 August 2024 for adults with hypoparathyroidism. Unlike teriparatide, which is dosed to create a deliberately pulsatile bone-building signal, palopegteriparatide releases PTH continuously to replace a missing hormone — a genuinely different therapeutic goal using closely related chemistry.

A synthetic peptide that mimics hepcidin, the liver hormone that controls iron. Discovered by Protagonist Therapeutics and sold by Takeda as Mimrylo, it was FDA-approved on August 28, 2026 to treat erythrocytosis (too many red blood cells) in adults with polycythemia vera. Given as a once-weekly injection, it limits the iron available to make red cells, so most patients no longer need regular phlebotomies.

A radioactive cancer drug built on a somatostatin-like peptide: DOTA-TATE carries a lutetium-177 atom to neuroendocrine tumour cells that display somatostatin receptors and irradiates them from the inside. Sold as Lutathera since 2018 (FDA) and 2017 (EU) for somatostatin-receptor-positive gastroenteropancreatic neuroendocrine tumours, it is given as four infusions eight weeks apart with a kidney-protecting amino-acid drip. Two more lutetium-177 dotatate products were approved in September 2026: Curium's Bexlutry on the 14th as a Type 5 NDA, and Lantheus's Bravnetsa on the 21st through the generic (ANDA) pathway — the only one of the three rated therapeutically equivalent to Lutathera.

An FDA-approved GnRH antagonist decapeptide given daily during IVF stimulation to block a premature LH surge — the drug that let fertility clinics abandon the three-week agonist down-regulation protocol.

An FDA-approved GnRH antagonist decapeptide supplied as a ready-to-use prefilled syringe, injected daily during IVF stimulation to prevent a premature LH surge — the first GnRH antagonist approved in the United States.

A once-weekly growth hormone analogue that hitches a ride on circulating albumin — the first long-acting GH approved in the United States for adults, now also approved in children for GH deficiency, small-for-gestational-age short stature, Noonan syndrome and idiopathic short stature.

A re-engineered glucagon that stays dissolved in water instead of clumping, which allowed the first glucagon rescue injection that needs no mixing — approved in 2021 for severe hypoglycaemia, and discontinued in the United States in 2026.

An eight-amino-acid peptide built almost entirely from D-amino acids that lowers parathyroid hormone in dialysis patients. It is the only drug known to work by forming a reversible disulfide bond with its own receptor — and it does nothing at all in pigs, because pig receptors carry the wrong amino acid at the one position that matters.

A diagnostic PET imaging agent: the same octapeptide that Lutathera uses to find neuroendocrine tumours, but carrying positron-emitting gallium-68 instead of a therapeutic radionuclide. FDA-approved as NETSPOT in June 2016 for localising somatostatin-receptor-positive neuroendocrine tumours in adults and children, it replaced octreotide scintigraphy as the standard of care and is the scan that decides who is eligible for peptide receptor radionuclide therapy.

A long-acting oxytocin analogue given as a single injection to prevent postpartum haemorrhage. Its heat-stable formulation is on the WHO Essential Medicines List because it survives without refrigeration — but Cochrane finds it no better than oxytocin at preventing bleeding, and its separate career as an intranasal drug for Prader-Willi syndrome ended in a failed Phase 3 in 2025.

A semi-synthetic polysaccharide with FDA approval for interstitial cystitis, also studied for joint and cartilage health.

An FDA-approved peripheral kappa opioid receptor agonist for chronic kidney disease-associated itch, without CNS side effects.

An FDA-approved GLP-2 analogue that promotes intestinal growth, used for short bowel syndrome.

The first FDA-approved treatment for Rett syndrome, a synthetic analogue of a naturally occurring IGF-1 tripeptide fragment.

An FDA-approved pan-somatostatin analog (SSTR1/2/3/5) used as first-line medical therapy for Cushing's disease and second-line for acromegaly.

An FDA-approved GnRH agonist delivered intranasally — the only GnRH agonist in routine US nasal-spray practice — used for endometriosis and central precocious puberty.

An FDA-approved GnRH agonist nonapeptide delivered via a once-yearly subcutaneous hydrogel implant, used for central precocious puberty (Supprelin LA) and historically for advanced prostate cancer (Vantas).

An FDA-approved synthetic decapeptide that selectively antagonizes the bradykinin B2 receptor, used as on-demand subcutaneous treatment for acute attacks of hereditary angioedema (HAE) in adults.

An endogenous gonadal dimeric protein hormone (TGF-β superfamily) that selectively suppresses pituitary FSH secretion and is used clinically as a biomarker for fertility, granulosa cell tumors, and prenatal screening.

An FDA-approved synthetic 20-amino-acid direct thrombin inhibitor used as an intravenous anticoagulant during percutaneous coronary intervention (PCI) and as a non-heparin option in patients with heparin-induced thrombocytopenia.

An FDA-approved synthetic cyclic heptapeptide glycoprotein IIb/IIIa receptor antagonist used as an intravenous antiplatelet agent during percutaneous coronary intervention and acute coronary syndromes, derived from the KGD motif of barbourin in southeastern pygmy rattlesnake venom.

An endogenous 32-amino-acid cardiac hormone secreted primarily by ventricular myocytes in response to wall stretch — the dominant natriuretic peptide in clinical practice and the basis of the BNP and NT-proBNP assays used worldwide for heart failure diagnosis, risk stratification, and management.

FDA-approved thrombopoietin-receptor agonist peptibody — four identical 14-amino-acid TPO-mimetic peptides covalently fused to a human IgG1 Fc scaffold — administered as a weekly subcutaneous injection for chronic immune thrombocytopenia (FDA 2008) and acute radiation syndrome (FDA January 2021). The first-in-class peptibody.

An endogenous 52-amino-acid vasodilator peptide of the CGRP/calcitonin family, isolated in 1993 by Kitamura and colleagues from human pheochromocytoma tissue, signaling through the calcitonin-receptor-like receptor (CLR) coupled with RAMP2 or RAMP3 to regulate vascular tone, endothelial barrier integrity, and cardio-renal physiology — and the source of two clinically meaningful therapeutic angles: MR-proADM as a sepsis and cardiovascular biomarker, and the anti-AM monoclonal antibody enibarcimab (formerly adrecizumab) as an investigational sepsis therapeutic.

An endogenous 22-amino-acid peptide identified in 1990 by Sudoh, Minamino, Kangawa, and Matsuo as the third member of the natriuretic peptide family. Unlike ANP and BNP, CNP is predominantly endothelial and chondrocytic rather than cardiac, signals through NPR-B (not NPR-A), and is the master driver of endochondral long-bone growth — the biology that vosoritide (Voxzogo) was engineered to mimic for achondroplasia.

A 19-amino-acid cyclic neuropeptide originally discovered in 1983 by Kawauchi and colleagues in chum salmon pituitary for its skin-pallor-inducing effect, and later identified as a potent orexigenic signal in mammals — released by lateral hypothalamic neurons, signaling primarily through MCH-R1 (a functional MCH-R2 exists in primates and dogs but is a pseudogene in rodents), and a long-running but unsuccessful obesity drug-discovery target.

A somatostatin-receptor-targeting cyclic octapeptide — octreotide with a tyrosine substitution and a DOTA chelator bolted to its N-terminus — that exists to carry radioactive metal to neuroendocrine tumours. As 68Ga-DOTATOC it is an FDA-approved PET imaging agent; as 177Lu-edotreotide (ITM-11) it is a radiotherapeutic that beat everolimus on progression-free survival in the Phase 3 COMPETE trial but received an FDA complete response letter in August 2026 over manufacturing issues. In September 2026 Telix agreed to acquire its developer, ITM, the same week a generic version of rival Lutathera won FDA approval.

A 14-amino-acid cyclic peptide that descends from a horseshoe crab antimicrobial, was built in Kyoto as an anti-HIV drug, and ended up approved for pulling stem cells out of bone marrow before a myeloma transplant. It clears the bloodstream in two hours but stays on its receptor for more than seventy-two.

An FDA-approved synthetic 25-amino-acid peptide derived from the venom of the marine cone snail Conus magus that selectively blocks N-type voltage-gated calcium channels in spinal cord nociceptive pathways. Delivered intrathecally via implanted pump for severe, refractory chronic pain — non-opioid, non-tolerizing, but constrained by a famously narrow therapeutic window and prominent neuropsychiatric side effects.

An FDA-approved synthetic 36-amino-acid peptide derived from the HR2 region of HIV-1 gp41. Enfuvirtide is the first-in-class HIV fusion inhibitor, given as a twice-daily subcutaneous injection in heavily treatment-experienced patients with multidrug-resistant HIV-1.

A once-weekly long-acting GLP-1 receptor agonist developed by GlaxoSmithKline as a recombinant fusion of two tandem GLP-1(7-36) sequences with human serum albumin — FDA-approved as Tanzeum (US) and Eperzan (EU) in 2014 for type 2 diabetes, achieved a positive cardiovascular outcomes signal in HARMONY OUTCOMES (Lancet 2018), but commercially withdrawn by GSK in 2017 due to weak market uptake against semaglutide and liraglutide.

A synthetic peptide derived from a protective protein found in gastric juice, widely discussed for tissue repair and recovery.

A selective growth hormone secretagogue that, in animal studies, released GH without the ACTH and cortisol rise seen with older GHRPs.

A synthetic version of the active region of thymosin beta-4, widely used for tissue repair, wound healing, and recovery from injuries.

A synthetic peptide analog of ACTH(4-10) developed in Russia, studied for cognitive enhancement and neuroprotection.

A naturally occurring protein that inhibits myostatin (the muscle growth limiter), studied for dramatic muscle growth potential.

A tripeptide fragment of alpha-MSH with potent anti-inflammatory properties, studied for inflammatory bowel disease and skin conditions.

A collagen-stimulating cosmetic peptide that signals skin to produce more collagen and extracellular matrix proteins.

The longevity protein discovered in 1997 as a mouse-aging-syndrome gene, now the subject of rigorous cognitive-aging research (the KL-VS variant confers real cognitive protection) and a grey-market 'Klotho peptide' industry that oversells early-stage academic work.

A synthetic peptide analog of tuftsin with anxiolytic and nootropic properties, developed in Russia.

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

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

A modified version of IGF-1 with extended half-life and reduced IGF binding protein affinity, used for muscle growth.

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

A collagen-boosting cosmetic peptide that mimics the body's wound-healing signal to stimulate collagen and elastin production in the skin.

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).

A naturally occurring neuropeptide with anti-inflammatory, neuroprotective, and immune-modulating properties. Early clinical data exists for pulmonary hypertension; other therapeutic uses remain under investigation.

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

An orally dosed octapeptide that acts locally in the gut to regulate tight junctions — the most clinically advanced celiac drug candidate until its Phase 3 was stopped at a pre-planned interim analysis in 2022 and its sponsor filed for Chapter 7 liquidation in 2023. Academic work continues, including a completed 107-patient Long COVID trial.

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; the global Phase 3 KaiNETIC program finished enrolling about 4,900 participants in September 2026, with topline data expected in mid-2028.

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, and the EloraTZP combination with tirzepatide showed up to 23.3% weight loss in a Phase 2b in obesity plus type 2 diabetes.

Berobenatide (PF-08653944, originally Metsera's MET-097i) is Pfizer's investigational ultra-long-acting, fully-biased GLP-1 receptor agonist designed for once-monthly injection — Phase 2b VESPER-3 showed up to 12.3% placebo-adjusted weight loss at 28 weeks with weekly titration followed by monthly doses, and a small open-label VESPER-1 extension group lost 15.9% over 32 weeks; Pfizer plans 10 Phase 3 trials and is targeting first approvals beginning in 2028.

Sederma's third-generation Matrixyl, built on a lysine-methionine-lysine tripeptide drawn from collagen VI and laminin and used at around 5 parts per million. The trade name claims six matrix constituents stimulated at once. The complication is that all three published human studies combined it with other actives — including one with 15% vitamin C — so no trial isolates what the peptide itself contributes.

A thymic peptide complex studied for immune system restoration, particularly in aging populations and immunocompromised states.

A skin-brightening peptide that inhibits cell-free mushroom tyrosinase about 17-fold more potently than hydroquinone, used topically for hyperpigmentation, melasma, and uneven skin tone. Against human tyrosinase the measured effect is far more modest, and skin penetration rather than enzyme potency is the limiting factor.

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.

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.

A 25-amino-acid antimicrobial peptide secreted by the liver that serves as the master hormone of systemic iron homeostasis. By binding and internalizing the iron-efflux transporter ferroportin, hepcidin restricts iron release from enterocytes and macrophages into the circulation — and is central to the pathophysiology of anemia of inflammation, hereditary hemochromatosis, and polycythemia vera.

An endogenous 9-amino-acid vasoactive peptide generated by kallikrein cleavage of kininogen; the primary effector of the kinin-kallikrein system, driving vasodilation, vascular permeability, pain, and the molecular basis of hereditary angioedema and ACE-inhibitor cough.

An FDA-approved first-in-class reversible proteasome inhibitor — a dipeptide boronic acid — that defined modern multiple myeloma therapy and the peptide-boronate drug class.

An endogenous 28-amino-acid cardiac hormone secreted by atrial myocytes in response to wall stretch; drives natriuresis, vasodilation, and renin-aldosterone suppression. Approved in Japan as carperitide (recombinant human ANP) for acute decompensated heart failure since 1995, but never FDA-approved in the United States.

A 9-amino-acid cyclic tumor-homing peptide (CRGDKGPDC, disulfide-cyclized) originally developed by Erkki Ruoslahti's group as iRGD and clinically advanced by Lisata Therapeutics. Activates the two-step CendR (C-end Rule) tumor-penetration pathway via αv-integrin binding plus neuropilin-1 engagement, transiently increasing tumor-vascular permeability for co-administered drugs. ASCEND Phase 2 in metastatic PDAC reported positive Cohort A (ASCO GI 2025) and Cohort B (ESMO GI 2025) signals. The Kuva Labs acquisition announced in March 2026 collapsed in July when Kuva could not finance it; Lisata terminated the merger, sued in Delaware, cut 72% of its staff, and has since agreed a reverse merger with Marea Therapeutics. No Phase 3 has ever been registered.

Ascletis Pharma's oral small-molecule GLP-1 receptor agonist, now in two global phase 3 obesity trials enrolling about 4,600 people. It exists in two formulations that are easy to confuse — a once-daily tablet and a subcutaneous depot with a half-life measured in weeks — and every efficacy number published for it so far is placebo-adjusted and sponsor-reported.

MetaVia Inc.'s once-weekly oxyntomodulin-analog dual GLP-1R/GCGR agonist, in-licensed from Dong-A ST. An 8-week 48 mg Phase 1 cohort showed −9.1% body weight at Day 54 and lower liver stiffness and liver fat on FibroScan in obesity. The Phase 1 Part 3 titration study reports 16-week data in Q4 2026 and 24-week data in Q1 2027.

Parabilis Medicines' stabilized helical peptide and the first direct inhibitor of the β-catenin:TCF protein-protein interaction — a target considered undruggable for thirty years. Phase 1/2 desmoid tumor data in Parabilis's 2026 IPO filings reported a 74% (14/19) RECIST 1.1 objective response rate, with FDA Fast Track (November 2025) and Orphan Drug (March 2026) designations and a registrational Phase 3 desmoid trial planned for H1 2027.

Hanmi Pharmaceutical's once-weekly CRFR2-selective urocortin-2 analog for obesity — a deliberately non-incretin approach designed to reduce fat mass while preserving or increasing lean mass, in contrast to the roughly one-quarter of weight lost as lean tissue on GLP-1 monotherapy. Licensed to Genentech in August 2026 for $190 million upfront within a deal worth up to about $2.3 billion. Still Phase 1, with no human data published.

AbbVie's long-acting amylin analog, licensed from Denmark's Gubra in 2025 for $350 million upfront. Its half-life of about 11 days let Phase 1 test weekly, every-other-week and monthly injections: weight fell 7.8–9.8% at 12 weeks on weekly dosing and 7.9% at 13 weeks on monthly dosing, vs about 0.3% on placebo. A Phase 2 trial aiming to enrol about 360 people began in August 2026.

A six-amino-acid cosmetic peptide built from two repeats of the Gly-Pro-Gln motif found in collagen IV and collagen XVII — the proteins that anchor the epidermis to the dermis. Sold as Collaxyl and used at around 0.002% in serums, it has one genuinely interesting randomised trial behind it, with two caveats most product copy omits: the trial tested a cyclized derivative, not the linear peptide, and the retinol it beat was dosed at 0.002%.

A naturally occurring neuropeptide that plays a central role in reproductive hormone regulation and fertility.

A mitochondria-targeted cardiolipin-stabilizing tetrapeptide FDA-approved in September 2025 as Forzinity for Barth syndrome — the first approved mitochondria-targeted peptide — with a Phase 3 trial ongoing in dry AMD and a new pivotal trial being planned in POLG-related mitochondrial myopathy.

A short-acting GLP-1 receptor agonist originally approved for type 2 diabetes, now studied for slowing motor decline in early Parkinson's disease.

A GnRH agonist nonapeptide approved in Europe and Canada since the 1980s for prostate cancer, endometriosis, fibroids, IVF, and precocious puberty — but never FDA-approved in the US.

An insulin-superfamily peptide hormone best known for softening pelvic ligaments and the cervix before childbirth, later developed as the failed heart-failure drug serelaxin.

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 every small-molecule APJ agonist program to date stopped in early trials.

The smallest hypothalamic releasing hormone — a tripeptide that drives TSH and prolactin secretion and was the first hypothalamic factor to be isolated and sequenced, earning Guillemin and Schally the 1977 Nobel Prize.

An FDA-approved second-generation, irreversible epoxyketone proteasome inhibitor — derived from the natural product epoxomicin — used intravenously in relapsed and refractory multiple myeloma.

A family of three corticotropin-releasing-factor-related neuropeptides — urocortin 1 (Vaughan and Vale, 1995), urocortin 2 (stresscopin-related peptide), and urocortin 3 (stresscopin) — that signal through CRH receptor types 1 and 2 to modulate the stress axis, cardiovascular function (potent inotropic and vasodilator effects in heart failure), appetite, and anxiety.

An 82-amino-acid anorexigenic peptide derived from N-terminal cleavage of the nucleobindin-2 (NUCB2) precursor, identified in 2006 by Oh-I, Shimizu, Mori and colleagues at Gunma University in a Nature paper as a satiety molecule that suppresses food intake through a leptin-independent hypothalamic-melanocortin pathway, with additional documented roles in glucose homeostasis, cardiovascular regulation, and stress responses — receptor unidentified.

An endogenous tetrapeptide (Tyr-Pro-Trp-Phe-NH2) discovered by James Zadina at Tulane in 1997 that is the most selective and potent natural agonist of the mu-opioid receptor identified to date — pharmacologically extraordinary, structurally unrelated to the YGGFL enkephalin family, and central to ongoing efforts to design opioid analgesics with reduced respiratory depression and abuse liability.

An endogenous somatostatin-family neuropeptide identified in 1996 by Luis de Lecea and J. Gregor Sutcliffe at the Scripps Research Institute, expressed in cortical and hippocampal GABAergic interneurons and signaling through all five somatostatin receptors plus the ghrelin receptor and a separate cortistatin-preferring binding site, with distinctive roles in slow-wave sleep, neuronal depression, and immune anti-inflammatory regulation that distinguish it from somatostatin despite extensive pharmacological overlap.

An endogenous neuropeptide isolated from porcine spinal cord by Naoto Minamino, Kenji Kangawa, and Hisayuki Matsuo at the National Cardiovascular Center in Osaka in 1985, named for its uterus-stimulating activity but now best characterized as an anorectic feeding-suppressing neuropeptide acting at NMUR1 (peripheral) and NMUR2 (central, brain-enriched) receptors with additional roles in circadian rhythm, stress, immunity, and Th2 inflammation.

An endogenous analgesic dipeptide (L-tyrosyl-L-arginine) discovered in 1979 by Hiroshi Takagi's group at Kyoto University and named for the city, producing morphine-like analgesia in rodent models through a Met-enkephalin-releasing mechanism rather than direct opioid receptor binding — one of the smallest endogenous neuropeptides and an enduringly studied alternative-analgesic candidate.

An endogenous 20-amino-acid neuropeptide named for its highly conserved N-terminal serine residue, discovered by Xu, Reinscheid, and Civelli at UC Irvine in 2004 by reverse-pharmacology deorphanization of GPR154 (now NPSR1) — pharmacologically distinctive for producing simultaneous wakefulness/arousal AND anxiolytic effects, a combination that classical anxiolytics do not deliver, and the molecular substrate for the natural-short-sleeper NPSR1 mutation identified in human pedigrees.

An endogenous human five-amino-acid peptide (Gln-Arg-Phe-Ser-Arg) discovered in 2006 by Catherine Rougeot and colleagues at the Institut Pasteur — a dual ectopeptidase inhibitor that simultaneously blocks neutral endopeptidase (neprilysin) and aminopeptidase N to prevent enkephalin degradation, thereby potentiating endogenous mu/delta-opioid signaling. Reported as a non-addictive endogenous analgesic with morphine-comparable potency in rodent models, with stabilized analogs (STR-324) advancing toward clinical pain indications.

A family of opioid-active peptides released by gastrointestinal digestion of bovine beta-casein, isolated by Brantl, Henschen, Teschemacher, and colleagues at the Max-Planck-Institut für Psychiatrie in 1979 — the seven-residue beta-casomorphin-7 (BCM-7) is the most studied member, central to the long-running A1 versus A2 milk debate, and the canonical example of an exogenous food-derived (exorphin) opioid peptide.

Chugai's investigational oral cyclic peptide pan-RAS inhibitor — a 'middle molecule' approach to one of the historically hardest oncology targets, with 2026 Mol Cancer Ther preclinical evidence of activity across diverse RAS genetic alterations, well beyond the G12C-only scope of FDA-approved small molecules.

A four-residue peptide that homes to injured brain and spinal cord by binding tenascin-C in the damaged extracellular matrix. Used in sixteen-plus studies as a targeting address for nanoparticles and siRNA, and since 2025 tested as a neuroprotective drug in its own right in mice. No human trial has ever been registered.

MetaVia Inc.'s first-in-class oral GPR119 agonist for MASH and type 2 diabetes, in-licensed from Dong-A ST. NOT a peptide — vanoglipel is a small-molecule drug (oxadiazole-piperidine-pyrimidine scaffold) that triggers endogenous release of the gut peptides GLP-1, GIP, and PYY. Listed here for cross-reference because of its peptide-axis mechanism. In a 16-week Phase 2a (n=109), ALT fell 18.1 U/L on 100 mg vs 4.7 U/L on placebo — just short of statistical significance at week 16 (p=0.0506) — with larger drops in patients who started with elevated ALT. MetaVia plans an End-of-Phase 2 FDA meeting in the second half of 2026.

An investigational TAT-conjugated peptide derived from the intracellular wedge domain of PTPσ that blocks the chondroitin-sulfate-proteoglycan brake on CNS axonal regeneration — developed by NervGen Pharma for spinal cord injury. The Phase 1b/2a CONNECT trial in chronic cervical SCI met one of its two co-primary endpoints in June 2025, and the Phase 3 registrational RESTORE trial (NCT07799532) began dosing in October 2026. It holds FDA Fast Track designation.

A long-acting interleukin-7 Fc-fusion protein from NeoImmuneTech that reliably expands CD4+ and CD8+ T cells in humans across a clinical programme its licensee describes as more than 800 subjects in fifteen studies — almost all in oncology and lymphopenia. Licensed to Tolerance Bio in August 2026 for thymus-related indications. Worth knowing that this is a ~80 kDa cytokine biologic rather than a peptide in any strict sense.

An investigational inhaled dry-powder peptide for idiopathic pulmonary fibrosis (IPF): a seven-amino-acid fragment (FTTFTVT) of caveolin-1's scaffolding domain, developed by Rein Therapeutics. A 24-patient Phase 1b showed it was well tolerated over 14 days and lowered several fibrosis-related markers in the airways; the 120-patient Phase 2 RENEW trial is enrolling, and the FDA granted Fast Track in August 2026. It is not approved, and research-chemical versions have no established basis for safe inhalation.

A once-weekly GLP-2 analogue engineered for extremely low clearance, developed to reduce intravenous feeding in short bowel syndrome. Its phase 3 trial met its primary endpoint, then the FDA asked for a second one after the sponsor discovered the trial had delivered less drug than intended.

A GLP-2 analogue with a six-lysine tail that made it stable enough to sell as a ready-to-use liquid autoinjector. Its phase 3 trial worked twice weekly and failed once weekly — the FDA asked for another trial, and Europe's regulator recommended approval in September 2026.

A 60-amino-acid protein engineered by phage display from a human clotting inhibitor, injected to stop hereditary angioedema attacks. It carries a boxed warning for anaphylaxis in 4% of patients, which is why it must be given by a clinician, why Europe never approved it, and why newer drugs have largely replaced it.

A cosmetic peptide engineered to imitate decorin, the proteoglycan that keeps dermal collagen fibrils thin and evenly sized. Sold as Decorinyl, it targets collagen organisation rather than collagen quantity — a genuinely distinct pitch resting on an unusually small evidence base: two PubMed records in total, one in vitro paper from the company that invented it and one human trial with six people per arm.

A nine-residue membrane-lysing peptide designed from bovine lactoferrin and injected directly into tumours. It kills cancer cells by rupturing their membranes rather than by any receptor, and the resulting messy necrosis is the point — it releases the danger signals that turn a tumour into its own vaccine. A Phase 2 trial in basal cell carcinoma reported 51 percent complete histologic clearance.

An 11-amino-acid peptide engineered from erythropoietin that retains tissue-protective effects without raising red blood cell count. Studied for neuropathic pain, small fiber neuropathy, and tissue repair.

A 17-amino-acid endogenous neuropeptide discovered in 1995 as the natural ligand of the orphan opioid-like receptor (now the NOP receptor), cleaved from the same prepronociceptin precursor as nocistatin but with functionally opposing pain pharmacology.

An FDA-approved (August 2001) recombinant human B-type natriuretic peptide given as an IV bolus and infusion for short-term symptom relief in acute decompensated heart failure. After the 2005 Sackner-Bernstein safety controversy and the largely neutral 2011 ASCEND-HF trial, nesiritide use collapsed and the product has since been discontinued — Drugs@FDA lists Natrecor (NDA 020920, Scios) with a marketing status of Discontinued.

An endogenous tetrapeptide (Thr-Lys-Pro-Arg) cleaved from residues 289-292 of the IgG heavy chain Fc region, discovered and named at Tufts University in 1970 by Najjar and Nishioka, and best characterized as a stimulator of macrophage and neutrophil phagocytosis, chemotaxis, and antimicrobial activity.

A recently discovered (Yosten, Lyu, Hsueh, Samson 2013) endogenous neuropeptide derived from the small integral membrane protein 20 (SMIM20) precursor — biologically active in two forms (PNX-14 and PNX-20), signaling through the orphan receptor GPR173, and characterized as a positive regulator of GnRH/kisspeptin reproductive signaling with additional documented roles in anxiety, memory, cardiovascular function, food intake, and thirst.

A cationic antimicrobial peptide derived from N-terminal proteolytic cleavage of lactoferrin (the iron-binding glycoprotein abundant in milk, saliva, tears, and neutrophil granules) — bovine lactoferricin (Lfcin-B, residues 17-41) is a 25-amino-acid amphipathic peptide identified by Bellamy and colleagues in 1992 as the bactericidal core of lactoferrin, with broad-spectrum activity against Gram-positive and Gram-negative bacteria, fungi, viruses, and parasites, plus apoptosis-inducing activity in tumor cell lines.

A 10-amino-acid mammalian member of the bombesin peptide family, isolated from porcine spinal cord by Naoto Minamino, Kenji Kangawa, and Hisayuki Matsuo at the National Cardiovascular Center in Osaka in 1983 — the same laboratory that produced ANP, BNP, NMU, and ghrelin. NMB signals through the bombesin receptor subtype 1 (NMBR / BB1), distinct from the GRP-preferring BB2 (GRPR), with documented roles in smooth-muscle contraction, thyroid TSH regulation, satiety, anxiety, thermoregulation, and pain/itch processing.

A synthetic hexapeptide analogue of leu-enkephalin, developed in the Soviet Union and still registered as a prescription medicine in Russia for peptic ulcer disease and acute pancreatitis. Its defining property is that it barely crosses the blood-brain barrier, which makes it an opioid-receptor agonist that acts almost entirely in the periphery — and which is why it became the model drug for the nanoparticle brain-delivery experiments of the 1990s.

Neuren's investigational oral analogue of cyclic glycine-proline, an IGF-1 metabolite — now in the first-ever Phase 3 trial for Phelan-McDermid syndrome. Despite the peptide-adjacent lineage it is a 194-dalton cyclic dipeptide (diketopiperazine), not a peptide, and it is approved nowhere.

A recombinant copy of the leech anticoagulant hirudin that beat both unfractionated heparin and enoxaparin in randomised trials with venographic endpoints — and then disappeared. Its European authorisation lasted seventeen years without the product ever being sold there, and it is discontinued in the United States.

A twelve-residue decoy peptide that turns down TREM-1, the amplifier that makes the immune response to infection overshoot. It is the most clinically advanced TREM-1 inhibitor and the clearest live test of precision immunomodulation in sepsis — but its Phase 2b trial missed its primary endpoint, and the registration trial agreed with the FDA in January 2024 has not yet appeared on ClinicalTrials.gov.

BPC-157 paired with arginine as a counter-ion, marketed as a more stable and more orally available form. No published study has ever compared it with the acetate salt, or studied it at all: the entire indexed literature on the arginate amounts to two sentences in one narrative review, with no data behind them.

A 12-amino-acid peptide cleaved from the BRINP2 protein that activates appetite-regulating neurons in the hypothalamus (not POMC neurons) through a pathway separate from GLP-1, leptin and MC4R. Identified by Stanford's Svensson lab with a computational prohormone-cleavage prediction tool and published in Nature (2025). Preclinical only — no human trial has been registered as of November 2026.

A senolytic peptide designed to selectively clear senescent cells by disrupting the FOXO4-p53 interaction, studied for anti-aging applications.

A terminally capped variant of Selank sold on the promise of a longer half-life. A systematic search of PubMed and Europe PMC returns zero publications on it — the phrases do not exist in the biomedical index at all. Where an acetylated sibling peptide has been tested, capping the N-terminus changed its biology rather than simply extending it.

The cosmetic-industry name for human epidermal growth factor — a 53-residue protein, not really an oligopeptide at all. Sold in serums as sh-Oligopeptide-1 or rh-Oligopeptide-1 and marketed for skin renewal, it has the weakest evidence-to-hype ratio of any peptide in common skincare use: a 2023 review in Cutaneous and Ocular Toxicology concluded the preclinical bioactivity of the cosmetic-grade material has not been proven, and China has banned EGF in cosmetics outright since 2019.

A synthetic melanocortin peptide studied for tanning, sexual function, and appetite suppression. Not FDA-approved; the FDA has issued public warnings against its use.

A synthetic tetrapeptide studied for its potential to activate telomerase and influence cellular aging.

A mitochondria-derived peptide with cytoprotective properties, studied for neuroprotection, metabolic regulation, and anti-aging effects.

A seven-residue fragment of spadin, itself cut from the sortilin propeptide, studied as a rapid-onset antidepressant acting at the TREK-1 potassium channel. Three papers exist on the molecule, the originating lab has been dormant since 2019, and its action on TREK-1 turns out to be biphasic — activating the channel at low doses and inhibiting it at higher ones.

A truncated form of IGF-1 missing the first 3 amino acids, with 10x greater potency and very short half-life for localized effects.

A splice variant of IGF-1 produced in response to mechanical stress on muscles, promoting satellite cell activation and muscle repair.

A PEGylated version of MGF with extended half-life for systemic muscle growth and recovery effects.

Orexin-A (hypocretin-1) is a 33-amino-acid neuropeptide made by neurons in the lateral hypothalamus that promotes wakefulness; loss of these neurons causes narcolepsy type 1. Orexin-A itself is not an approved drug: nasal-spray orexin-A has only small single-dose human studies, and the approved orexin medicines are small molecules.

A CNTF-derived neurogenic tetrapeptide with an adamantylated glycine for brain penetration, studied for fifteen years in Alzheimer, Down syndrome and traumatic brain injury mouse models — almost always given orally in the diet. Despite an active patent estate and a company developing it, P021 has never entered a human trial of any phase.

A terminally capped variant of Epithalon with zero publications of its own — six phrase searches return nothing, and the FDA's own exhaustive 2026 literature review never encountered it. The parent peptide now has one independent telomerase replication, from Brunel University London, which also found telomere lengthening in breast cancer cells via ALT activation.

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 in mice without physical activity. It has never been tested in a human trial, and WADA banned it by name from 2027.

A small synthetic peptide designed to mimic waglerin-1 from Temple Pit Viper venom, marketed as blocking muscle acetylcholine receptors to soften expression lines. Often called 'topical Botox' — in the manufacturer's cell test it cut nerve-driven muscle-cell contractions by 82% at 2 hours, an effect that faded within days.

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 naturally occurring antimicrobial peptide that plays a key role in innate immune defense.

A potent angiotensin IV analog studied for cognitive enhancement. Its Dihexa-derived prodrug fosgonimeton failed its Phase 2/3 Alzheimer's trial (LIFT-AD, 2024), and the foundational 2014 HGF/c-Met mechanism paper was retracted in 2025 — material context that reshapes how the preclinical literature should be read.

A nine-amino-acid peptide isolated from rabbit blood in 1977 and named for the EEG pattern it appeared to induce. Nearly fifty years on there is still no DSIP gene, no identified precursor protein and no receptor — and the two independent double-blind insomnia trials both concluded the sleep benefit was not clinically meaningful.

A cosmetic octapeptide marketed as a longer, stronger Argireline for expression lines. It has zero peer-reviewed publications of its own — the string does not appear in PubMed's index at all — and the closest assessed sibling was cleared by the Cosmetic Ingredient Review only up to 0.005%, against the 3-10% these products typically use.

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

An experimental fat-targeting peptide that selectively destroys blood vessels feeding white adipose tissue. Produced dramatic fat loss in primate studies alongside dose-dependent kidney injury, reached a first-in-human Phase 1 trial that enrolled four patients, and has gone nowhere since.

A synthetic signal peptide that mimics thrombospondin-1 to activate TGF-beta signaling, stimulating type I and III collagen production in dermal fibroblasts for anti-wrinkle and skin-firming effects.

A synthetic enkephalin-mimicking pentapeptide that reduces acetylcholine release at the neuromuscular junction, relaxing facial muscles and smoothing expression wrinkles. In Lipotec's 28-day comparison, a cream with 5% Leuphasyl solution cut wrinkles by about 12% alone and about 25% combined with Argireline.

A synthetic pentapeptide (Gly-Pro-Arg-Pro-Ala-NH2) used in anti-wrinkle creams and described as a curare-like blocker of the muscle acetylcholine receptor. Its headline claim of up to 49% smaller wrinkles in 28 days is unpublished manufacturer data.

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

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.

A short tripeptide studied for neuroprotective and cognitive-enhancing properties, part of the Khavinson peptide bioregulator family.

A zinc-dependent thymic peptide involved in T-cell maturation, studied for immune restoration and anti-inflammatory applications.

A synthetic peptide bioregulator targeting brain cortex function, studied for cognitive enhancement and neuroprotection in aging.

A synthetic tripeptide bioregulator (Lys-Glu-Asp) from the Khavinson system, studied for vascular protection, endothelial function, and age-related cardiovascular decline.

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

A synthetic tripeptide bioregulator (Ala-Glu-Asp, AED) from the Khavinson system, sold for cartilage and joint health. Its published research is all cell culture and rat work from one research network — in aging chondrocytes and stem cells, but also in kidney and skin cells.

A naturally occurring immunopeptide that controls T cell migration into inflamed tissues. Discovered at the University of Birmingham, PEPITEM shows preclinical promise for inflammatory arthritis, multiple sclerosis, lupus, psoriasis, bone loss, and age-related immune decline.

A chimeric p53-penetratin anticancer peptide that binds HDM-2 on cancer cell membranes and punches pores in them, largely sparing normal cells in its developers' studies. Tested in cell culture and several mouse models (including leukemia); never tested in humans.

An immunomodulatory tetrapeptide derived from human IgG, used in cosmeceuticals as Palmitoyl Tetrapeptide-7 to suppress skin inflammation (IL-6) and support anti-aging skin repair.

A palmitoylated cosmeceutical tripeptide (Ala-His-Lys) studied for hair growth stimulation via dermal papilla cell proliferation and anti-apoptotic signaling, as well as collagen synthesis and skin rejuvenation.

A synthetic immune-stimulating dipeptide (Glu-Trp) first isolated from the calf-thymus extract Thymalin, sold in Russia since 1990 as Timogen, and tested in US cancer trials as oglufanide (IM862), where a Phase III trial found no benefit over placebo.

A synthetic decapeptide (Arg-Asp-Gly-Gln-Ile-Leu-Ser-Thr-Trp-Tyr) marketed as the active in β-WHITE™, positioned as a topical skin-brightening ingredient that suppresses MITF-driven melanogenesis rather than directly inhibiting tyrosinase.

A low-molecular-weight dimeric dipeptide mimetic of nerve growth factor's fourth beta-turn loop, designed to reproduce NGF's neurotrophic effects at TrkA without the pain-sensitizing side effects of full-length NGF.

A low-molecular-weight dimeric dipeptide mimetic of the fourth loop of brain-derived neurotrophic factor (BDNF), designed at the Zakusov Institute in Moscow and studied preclinically as an antidepressant and neuroprotective agent.

A copper peptide — the copper-complexed tripeptide alanine-histidine-lysine, widely marketed as Copper Tripeptide-3 — studied for hair follicle stimulation and dermal papilla cell survival. A structural cousin of the better-known copper peptide GHK-Cu with a distinct, hair-focused research profile.

A 23-amino-acid peptide proposed in 2005 by Aaron Hsueh's group at Stanford as a ghrelin-opposing anorectic hormone encoded by the same preproghrelin gene, with a contested physiological role — the original Science paper has been only partially replicated, and obestatin's identity as a true ghrelin antagonist on food intake remains one of the most public failure-to-replicate stories in peptide endocrinology.

A cosmetic tetrapeptide marketed for under-eye puffiness and dark circles, developed by Lipotec (now Lubrizol Life Science) and used in topical cosmetic formulations targeting periorbital edema, glycation reduction, and capillary permeability — with the standard cosmetic-grade evidence base of in-house formulation studies rather than independently published peer-reviewed clinical trials.

A 5-residue active fragment of the 49-residue thymic peptide thymopoietin, characterized in the late 1970s and 1980s as an immunomodulator with effects on T-cell maturation. Used historically as an investigational and limited-clinical agent (Timunox in some markets) for chronic immune dysfunction including atopic dermatitis and rheumatoid arthritis, with the short plasma half-life — about 30 seconds in human plasma in vitro (Tischio 1979). The paper's own conclusion runs the other way, though: because the pentapeptide is active in vivo despite that, the authors inferred it “may rapidly trigger changes in responsive cells; sustained circulating levels may not be required for activity.”

Epithalamin is not a peptide. It is a polypeptide extract of bovine pineal gland — a multi-component "cytomedin" preparation from the Khavinson programme in St. Petersburg, alongside Thymalin, Cortexin and Prostatilen. It matters mainly because the internet constantly confuses it with Epitalon (AEDG), the single synthetic tetrapeptide that Khavinson's group designed from epithalamin's amino-acid composition. Most of the human longevity evidence marketed for "epitalon" was in fact generated with epithalamin, and a 2026 independent review warns the two should not be cited interchangeably.

MBX Biosciences' once-weekly GLP-1 receptor antagonist for post-bariatric hypoglycemia. It cleared Phase 1, hit proof of concept in a 20-patient open-label Phase 2a in May 2026 — and was then shelved, with MBX stating it would not fund a Phase 2b. Its competitor avexitide has since posted positive Phase 3 data.

Vertex Pharmaceuticals' investigational cyclic peptide-oligonucleotide conjugate for myotonic dystrophy type 1 (DM1), using Entrada Therapeutics' Endosomal Escape Vehicle (EEV) cyclic peptide to deliver an antisense oligonucleotide targeting DMPK mRNA.

Avacta's FAP-activated peptide-drug conjugate of doxorubicin (INN faridoxorubicin) — a tumor-microenvironment-activated chemotherapy designed to deliver doxorubicin selectively to fibroblast activation protein (FAP)-expressing tumors. The Phase 1a/1b trial (NCT04969835) closed to enrollment in 2026 and reported its strongest signal at ESMO 2026 (October 26, 2026): median progression-free survival of 11.4 months in a 32-patient salivary gland cancer efficacy subset, against published historical benchmarks of 6–6.7 months. Across 111 patients dosed, fewer than 4% had a significant drop in left ventricular ejection fraction and no cardiomyopathy of any grade was reported. The compound has no peer-reviewed primary publication — every efficacy number traces to company releases and conference abstracts.

MBX Biosciences' investigational once-monthly GLP-1/GIP dual agonist prodrug for obesity — an extended-action approach that would substantially reduce dosing frequency versus weekly GLP-1/GIP agents like tirzepatide.

MBX Biosciences' preclinical obesity candidate — a single prodrug construct the company says combines GLP-1, GIP, glucagon and dual amylin/calcitonin receptor activity, designed for once-monthly dosing. It is in IND-enabling studies with no registered clinical trial, and despite its 'amycretin prodrug' label it is not a prodrug of Novo Nordisk's amycretin.

Ascletis Pharma's GLP-1/GIP dual agonist peptide, formulated as a subcutaneous lipid depot intended for once-monthly dosing rather than weekly. Its phase 1 began dosing in August 2026 with tirzepatide as an active comparator, and no human data has been reported.

Ascletis Pharma's amylin receptor agonist peptide, developed in two formulations at once — a subcutaneous lipid depot aimed at monthly or quarterly dosing, and a once-weekly oral tablet. Both entered first-in-human trials in autumn 2026. Its most interesting engineering claim is that it does not fibrillate at neutral pH.

An 8-amino-acid fragment of activity-dependent neuroprotective protein (ADNP) that stabilises microtubules via the EB1/EB3 end-binding proteins. Sold in gray-market channels as a nootropic despite having failed a 313-patient Phase 2/3 trial in progressive supranuclear palsy and never once met a prespecified cognitive endpoint in any randomised trial.

A synthetic small molecule built to imitate the defensins — the body's own antimicrobial peptides — without being a peptide at all. It has been tested against bacterial skin infections, oral mucositis, ulcerative colitis and COVID-19, and the most striking recent findings are not antibacterial but antifungal: brilacidin restores the activity of caspofungin against fungi that are intrinsically resistant to it.

A synthetic dipeptide bioregulator (Glu-Asp) from the Khavinson system, studied for bladder function support, urinary health, and age-related urogenital decline.

A synthetic tetrapeptide bioregulator (Lys-Glu-Asp-Ala) from the Khavinson system, studied for chromatin decondensation, hepatoprotection, and immune cell reactivation in aging.

A synthetic tripeptide bioregulator (Glu-Asp-Gly) from the Khavinson system, studied for respiratory and bronchial mucosal health, anti-inflammatory gene regulation, and stress protection in lung tissue.

A naturally occurring heptapeptide from frog skin and one of the most potent mu-opioid receptor agonists known, approximately 40 times more potent than morphine.

A milk-derived hexapeptide from bovine beta-casein with immunomodulatory, anticancer, and hepatoprotective properties studied primarily in ovarian cancer and liver disease models.

A liver- and brain-derived peptide hormone that regulates energy balance, insulin sensitivity, and endothelial function — investigated as both a cardiometabolic biomarker and a potential therapeutic target, though no clinical drug program exists yet.

A yeast-derived cosmetic hexapeptide that switches on proteasome, autophagy-related, and antioxidant (Nrf2) genes in cultured human lung and skin fibroblasts — positioned as a proteostasis-based anti-aging ingredient.

An endogenous tetrapeptide cleaved from thymosin β4 with broad antifibrotic activity across the heart, kidney, lung, and liver — historically developed as the chemoprotective drug goralatide and more recently studied as a biomarker of ACE-inhibitor activity.

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 nine-amino-acid cosmetic peptide designed as an α-MSH antagonist at the MC1R receptor on melanocytes, formulated topically as a skin-brightening and anti-hyperpigmentation ingredient.

A palmitoylated dipeptide cosmetic ingredient best documented as one of the two synthetic peptides in DSM's Syn-Tacks complex, marketed to strengthen the dermal-epidermal junction for firmer, more elastic skin. Current EU and supplier listings name it Palmitoyl Dipeptide-5 Diaminohydroxybutyrate; it has no peer-reviewed literature.

A collagen-derived tripeptide (glycine-proline-hydroxyproline) that is the most abundant repeating motif in type I collagen — used as a cosmetic INCI ingredient in topical formulations and present in oral collagen hydrolysate supplements marketed for skin and joint support.

A synthetic immunomodulatory dipeptide (Lys-Glu) isolated from the thymic peptide complex Thymalin, studied by the Khavinson group for T-cell support, gene-expression modulation, and lifespan endpoints in aging rodents.

A synthetic tetrapeptide bioregulator (Ala-Glu-Asp-Leu) from the Khavinson system, studied for bronchial epithelial maintenance, mucin gene regulation, and adjunct use in chronic bronchitis and COPD within the Russian bioregulator framework.

A synthetic tetrapeptide bioregulator (Ala-Glu-Asp-Arg, AEDR) from the Khavinson program, patented as a 'peptide substance restoring myocardium function' and studied in rat heart-tissue cultures, a rat tumor model and the developer's own patent experiments. Often mislabeled online as the tripeptide AED, which is Cartalax.

A synthetic short peptide bioregulator (commonly cited as the tetrapeptide Lys-Glu-Asp-Pro) from the Khavinson program, positioned as a prostate-tissue-specific regulator and studied in rodent models for benign prostatic hyperplasia, chronic prostatitis, and age-related prostate function decline.

A synthetic tetrapeptide bioregulator (commonly cited as Lys-Glu-Asp-Gly, KEDG) from the Khavinson program, positioned as the testicular tissue-targeted short peptide and discussed for age-related decline in Leydig cell function, male reproductive aging, and androgen deficiency.

A 32-amino-acid endogenous peptide hormone that acts as the second ligand of the APJ (apelin) receptor — essential for embryonic cardiovascular development and emerging as a candidate therapeutic for pulmonary hypertension, pre-eclampsia, heart failure, and chronic kidney disease. Currently a research molecule with no approved clinical product.

A second-generation synthetic growth hormone-releasing heptapeptide (also designated KP 101) from the Bowers-Momany program, developed in the early 1990s AFTER the prototype GHRP-6 — not before it, despite the lower number. Clinically tested once in children by intravenous bolus, notable for an unusual thyroid effect, and long since superseded by GHRP-2, hexarelin, ipamorelin and MK-677.

A synthetic short peptide (commonly cited as Glu-Asp-Pro, EDP) from the Khavinson program at the St. Petersburg Institute of Bioregulation and Gerontology, positioned as the thymus / immune-system tissue-targeted bioregulator and the synthetic counterpart to the natural-extract preparation Thymalin — used within the Khavinson framework for age-related immune decline, with the thinnest peer-reviewed footprint in the bioregulator catalog.

A 5-residue peptide derived from splenopoietin (the spleen-derived counterpart to thymopoietin) and characterized in the late 1980s and 1990s as an immunomodulator alongside the closely related thymopentin (TP-5). Singh and Biswas's 1998 Immunology Research review established splenopentin and thymopentin as paired immunomodulatory pentapeptides; the molecule has remained research-tier without clinical translation.

A natural-extract retinal-tissue polypeptide preparation in the Khavinson catalog, used in Russian ophthalmology practice for diabetic retinopathy, retinitis pigmentosa, and other retinal disorders. There is no published study of Visoluten itself. A PubMed search for the product name, in either common transliteration, returns zero records, and the two papers usually cited for it are about other members of the same catalogue: Trofimova and Khavinson (2001) treated 104 patients with diabetic retinopathy using retinalamine, epithalamine and cortexine, and the 2014 Khavinson paper discusses peptide bioregulators generically in retinitis pigmentosa without naming any product. Neither mentions Visoluten, with the broader Khavinson framework's mechanistic and evidence limitations applying.

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.

A 13-residue cyclic peptide that blocks the CD28 immune checkpoint, designed by a reinforcement-learning pipeline that generated 420 candidate sequences of which three were made. Its defining property is not potency but reversibility — it washes out in hours, where antibodies against the same target persist for weeks.

Avacta's second pre|CISION-platform peptide-drug conjugate — a fibroblast activation protein (FAP)-cleavable peptide linker masking exatecan, the topoisomerase-I payload behind the deruxtecan ADC class. First patient dosed in the Phase 1 FOCUS-01 trial (NCT07454642) on March 31, 2026. Human safety and pharmacokinetic data arrived in September 2026: across 19 patients through the first three dose levels, Avacta reported zero neutropenia and a plasma profile it interprets as the conjugate sitting in a tumour 'drug reservoir'. No efficacy data yet, and no peer-reviewed publication of any kind.

A thyroid-hormone-receptor β-selective agonist — technically a small-molecule diphenylmethane thyromimetic (~314 Da), not a peptide — included in this atlas as an adjacent-literature reference because it comes up in peptide-metabolism, MASLD, and lipid-modulation discussions and is frequently confused with peptide-class drugs. Originally developed for dyslipidemia (Karo Bio, 1998); now pursued for CNS demyelinating disease via the brain-penetrant amide prodrug Sob-AM2.

A GLP-1/GIP/FGF21 triple-agonist Fc-fusion protein from Shanghai Minwei Biotechnology, in Chinese Phase Ib and Phase II trials for obesity — including a cohort specifically enrolling semaglutide-intolerant patients. Licensed ex-Greater China to Denmark's Sidera Bio in October 2025. The mechanism is genuinely interesting; the public evidence is one sponsor conference abstract and no human results at all.

The first antibiotic of a genuinely new class in decades — a protegrin-derived macrocyclic peptide that kills Pseudomonas aeruginosa by jamming the machine that builds its outer membrane. Two Phase 3 trials were halted in 2019 when acute kidney injury appeared in 56 percent of treated patients, and it is now the field's standard cautionary tale about peptide antibiotics and the kidney.

A neuropeptide encoded in the same prepronociceptin gene as nociceptin/orphanin FQ that functionally opposes nociceptin's actions on pain, memory, anxiety and feeding through targets distinct from the NOP receptor — though its own effect on pain is biphasic, anti-allodynic at low doses and frankly pro-nociceptive at high ones.

An amphibian skin-derived cationic antimicrobial peptide from the Phyllomedusa sauvagii frog, studied in vitro for antibacterial, antifungal, antiparasitic, and antiviral membrane-disrupting activity. "DS5" is an ambiguous label across the peptide literature; this entry covers dermaseptin S5 specifically.

A chemically modified version of Semax designed for improved stability. No published clinical or preclinical data exists for this specific compound.

A long-acting dual GIP/GLP-1 receptor agonist from Eli Lilly, in Phase 3 trials for alcohol use disorder and major depressive disorder, with Phase 2 studies in bipolar disorder, schizophrenia, opioid use disorder, smoking relapse prevention, asthma, COPD and IBS, and Phase 1 studies in obesity. Its dosing interval has not been disclosed in any trial registration, and the widely repeated once-monthly description is not Lilly's own.

An enhanced derivative of Semax with N-terminal acetylation and C-terminal adamantane modification, engineered for superior blood-brain barrier penetration, BDNF upregulation, and sustained nootropic effects.

A synthetic tripeptide bioregulator (Glu-Asp-Leu, EDL) from the Khavinson system, sold commercially for liver and gastrointestinal support — although every published study of the EDL sequence is about the kidney, not the liver.

A 27-residue linear peptide corresponding to residues 7-33 of the B-chain of human relaxin-2 — the name encodes the residue span, not the length — designed by Mohammed Akhter Hossain's group at the Florey Institute as the first functionally selective RXFP1 agonist, biased toward pERK1/2 signalling over cAMP. Far simpler and cheaper to synthesise than two-chain relaxin and antifibrotic across rodent heart, lung and kidney models, but it is less stable in serum than the parent hormone rather than more, and it has never been given to a human.

PepGen's cell-penetrating-peptide-conjugated PMO for Duchenne muscular dystrophy exon 51 skipping, voluntarily discontinued on 28 May 2025 after the Phase 2 CONNECT1 trial's 10 mg/kg cohort restored dystrophin to only 0.59% of normal. PepGen wound down all DMD work and pivoted to its myotonic dystrophy programme, which remains its lead.

A peptide name with no verifiable record in any scientific, regulatory, or chemical database. Searches of PubMed, Europe PMC, ClinicalTrials.gov, PubChem, ChEMBL, UniProt, DailyMed and FDA labelling return nothing for 'Adatide'. Anyone who encountered this name may be thinking of adipotide or adamax, which are real and documented.