Explore the
Peptide Library.

Browse approved medicines and investigational or experimental peptides.Keep human and preclinical evidence distinct from regulatory status.

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Grades describe evidence for a specific claim. They are separate from regulatory approval.

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Evidence describes a specific claim; approval applies to a medicine, use, and jurisdiction. Open each profile for its sources, limitations, and review status.

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56 peptides

FDA-approved peptide medicine
Conceptual molecular chain in a fibrous cellular environment.

Abaloparatide

Also known as Tymlos, BA058

Synthetic analogue of human parathyroid hormone-related protein (PTHrP 1-34) approved for postmenopausal women and men with high fracture risk osteoporosis.

Evidence
Strong Evidence
Status · U.S.
Approved Medicine
Tissue RepairView profile
FDA source for Abaloparatide ↗
FDA-approved alpha-MSH analogue (MC1 receptor agonist) implant
Conceptual molecules beside a glowing network of cell-like branches.

Afamelanotide

Also known as Scenesse, CUV1647, NDP-MSH

Alpha-MSH analogue implant (Scenesse) approved to increase pain-free light exposure in adults with erythropoietic protoporphyria; vitiligo is investigational.

Evidence
Moderate Evidence
Status · U.S.
Approved Medicine
Skin & HairView profile
FDA source for Afamelanotide ↗
Synthetic C-terminal hGH fragment
Conceptual molecular chain over warm flowing light patterns.

AOD-9604

Also known as Advanced Obesity Drug 9604, Tyr-hGH 177-191

Modified 16-amino-acid fragment of human growth hormone studied in Phase 2b obesity trials, where it failed to demonstrate significant weight reduction.

Evidence
Early Human Evidence
Status · U.S.
Unapproved
MetabolicView profile
Cosmetic peptide ingredient (not a drug)
Conceptual molecular chain over warm flowing light patterns.

Argireline

Also known as Acetyl Hexapeptide-3, Acetyl Hexapeptide-8, Ac-EEMQRR-NH2

Acetyl hexapeptide-8, a SNAP-25-mimicking cosmetic peptide. Small topical wrinkle trials; limited skin penetration; not a drug.

Evidence
Early Human Evidence
Status · U.S.
Unapproved
Skin & HairView profile
Synthetic research peptide
Conceptual cellular forms connected by blue and green molecular patterns.

BPC-157

Also known as Body Protection Compound 157, PL 14736, Bepecin

A 15-amino-acid synthetic peptide studied in animal models of tendon, gut, and muscle healing. Lacks controlled human clinical trial evidence.

Evidence
Preclinical Evidence
Status · U.S.
Unapproved
Tissue RepairView profile
FDA-approved peptide medicine
Conceptual violet protein ribbon amid flowing light patterns.

Bremelanotide

Also known as Vyleesi, PT-141

FDA-approved cyclic melanocortin receptor agonist indicated for the treatment of hypoactive sexual desire disorder (HSDD) in premenopausal women.

Evidence
Strong Evidence
Status · U.S.
Approved Medicine
ReproductiveView profile
FDA source for Bremelanotide ↗
Investigational peptide medicine
Conceptual molecular chain over warm flowing light patterns.

Cagrilintide

Also known as CagriSema, cagrilintide-semaglutide

An investigational long-acting amylin analogue from Novo Nordisk, studied alone and with semaglutide (CagriSema) in phase 3 obesity and diabetes trials. Not FDA-approved.

Evidence
Moderate Evidence
Status · U.S.
Investigational
MetabolicView profile
Synthetic GHRH analogue
Conceptual blue and violet protein helix in a molecular landscape.

CJC-1295

Also known as Modified GRF 1-29, DAC:GRF, Tetrasubstituted GHRH

Synthetic growth hormone releasing hormone (1-29) analogue engineered for extended half-life; evaluated in early Phase 1/2 human trials.

Evidence
Early Human Evidence
Status · U.S.
Unapproved
Growth Hormone AxisView profile
Angiotensin IV-derived research compound (unapproved)
Conceptual protein forms around a cellular membrane.

Dihexa

Also known as PNB-0408, ATH-1001, Hexanoyl-Tyr-Ile-Ahx-NH2

An angiotensin IV-derived compound studied for memory in rodents only. A key mechanism paper was retracted; FDA reports no human exposure data.

Evidence
Preclinical Evidence
Status · U.S.
Unapproved
NeuropeptideView profile
Research neuropeptide (unapproved)
Conceptual blue molecular chain on a pale background.

DSIP

Also known as Delta Sleep-Inducing Peptide, Emideltide

Delta sleep-inducing peptide, a 1970s rabbit-derived nonapeptide. Small, old insomnia trials gave conflicting results; no receptor identified.

Evidence
Early Human Evidence
Status · U.S.
Unapproved
NeuropeptideView profile
FDA-approved GLP-1 receptor agonist (Fc-fusion protein)
Conceptual multicolored protein ribbon among green cellular forms.

Dulaglutide

Also known as Trulicity, LY2189265

Once-weekly GLP-1 receptor agonist (Trulicity) for type 2 diabetes; REWIND showed a modest drop in major cardiovascular events.

Evidence
Strong Evidence
Status · U.S.
Approved Medicine
MetabolicView profile
FDA source for Dulaglutide ↗
FDA-approved peptide medicine
Conceptual protein forms around a cellular membrane.

Elamipretide

Also known as Forzinity, SS-31, MTP-131, Bendavia, Szeto-Schiller peptide

Mitochondria-targeted peptide given FDA accelerated approval (Forzinity) in 2025 for Barth syndrome, based on a very small trial; other trials were negative.

Evidence
Moderate Evidence
Status · U.S.
Approved Medicine
FDA source for Elamipretide ↗
Synthetic pineal tetrapeptide
Conceptual protein forms around a cellular membrane.

Epitalon

Also known as Epithalon, Ala-Glu-Asp-Gly, AGAG tetrapeptide

Synthetic tetrapeptide modeled on pineal extract epithalamin; investigated in rodent aging models for telomerase activation and pineal modulation.

Evidence
Preclinical Evidence
Status · U.S.
Unapproved
LongevityView profile
FDA-approved peptide medicine
Conceptual cyan molecular chain above a softly colored cellular landscape.

Exenatide

Also known as Byetta, Bydureon, synthetic exendin-4

First-in-class synthetic exendin-4 GLP-1 receptor agonist approved by the FDA in 2005 for glycemic control in adult patients with type 2 diabetes.

Evidence
Strong Evidence
Status · U.S.
Approved Medicine
MetabolicView profile
FDA source for Exenatide ↗
Endogenous copper tripeptide complex
Conceptual pastel protein ribbon above a cellular landscape.

GHK-Cu

Also known as Copper Peptide, Glycyl-L-histidyl-L-lysine copper, Copper tripeptide-1

Naturally occurring copper-binding tripeptide investigated for extracellular matrix remodeling, collagen synthesis, and topical skin health.

Evidence
Early Human Evidence
Status · U.S.
Unapproved
Skin & HairView profile
Endogenous peptide hormone
Conceptual blue and violet protein helix in a molecular landscape.

Ghrelin

Also known as Acylated Ghrelin, Lenomorelin, Hunger hormone

28-amino-acid acylated gut hormone that activates the growth hormone secretagogue receptor (GHSR-1a) to drive appetite, feeding behavior, and pulsatile GH release.

Evidence
Strong Evidence
Status · U.S.
Investigational
Growth Hormone AxisView profile
Synthetic growth hormone secretagogue
Conceptual molecular chain beside a blue cellular interface.

GHRP-2

Also known as Pralmorelin, KP-102, Growth hormone-releasing peptide-2

A synthetic GH-releasing hexapeptide (pralmorelin) used in Japan as a diagnostic test for GH deficiency. Not FDA-approved; FDA flags compounded injectable forms.

Evidence
Early Human Evidence
Status · U.S.
Unapproved
Growth Hormone AxisView profile
Synthetic growth hormone secretagogue
Conceptual blue and violet protein helix in a molecular landscape.

GHRP-6

Also known as Growth hormone-releasing peptide-6, Growth hormone-releasing hexapeptide, SKF-110679

A synthetic six-amino-acid peptide that triggers growth hormone release via the ghrelin receptor. Used in research and diagnostic tests; not an approved medicine.

Evidence
Early Human Evidence
Status · U.S.
Unapproved
Growth Hormone AxisView profile
Endogenous incretin peptide hormone
Conceptual cyan molecular chain above a softly colored cellular landscape.

GIP

Also known as Glucose-Dependent Insulinotropic Polypeptide, Gastric Inhibitory Polypeptide

Endogenous 42-amino-acid incretin secreted by enteric K-cells; synergistic regulator of pancreatic beta-cell insulin secretion and adipose metabolism.

Evidence
Strong Evidence
Status · U.S.
Investigational
MetabolicView profile
Endogenous incretin peptide hormone
Conceptual coral protein ribbon above pale cellular forms.

GLP-1

Also known as Glucagon-Like Peptide-1, GLP-1 (7-36) amide, Incretin hormone

Primary intestinal incretin hormone that stimulates glucose-dependent insulin secretion; native blueprint for the entire GLP-1 receptor agonist drug class.

Evidence
Strong Evidence
Status · U.S.
Investigational
MetabolicView profile
FDA-approved peptide medicine / Endogenous hormone
Conceptual molecular chain over warm flowing light patterns.

Glucagon

Also known as GlucaGen, Baqsimi, Gvoke, Zegalogue

Endogenous 29-amino-acid pancreatic counter-regulatory hormone; FDA-approved emergency treatment for severe acute hypoglycemia.

Evidence
Strong Evidence
Status · U.S.
Approved Medicine
MetabolicView profile
FDA source for Glucagon ↗
Synthetic native GnRH (discontinued U.S. human medicine)
Conceptual molecular chain in a fibrous cellular environment.

Gonadorelin

Also known as GnRH, LHRH, Factrel, Lutrepulse

Synthetic copy of the brain hormone GnRH. Former U.S. human products (Factrel, Lutrepulse) are discontinued; pulsatile GnRH can restore ovulation in hypothalamic amenorrhea.

Evidence
Moderate Evidence
Status · U.S.
Unapproved
ReproductiveView profile
Synthetic growth hormone secretagogue
Conceptual cyan molecular chain above a softly colored cellular landscape.

Hexarelin

Also known as Examorelin, EP-23905

A synthetic GH-releasing hexapeptide related to GHRP-6. Studied in short human hormone and heart experiments; never an approved medicine.

Evidence
Early Human Evidence
Status · U.S.
Unapproved
Growth Hormone AxisView profile
FDA-approved peptide medicine / Endogenous hormone
Conceptual multicolored protein ribbon among molecular forms.

Insulin

Also known as Human Insulin, Regular Insulin, rDNA Insulin

Two-chain 51-amino-acid metabolic peptide hormone central to glucose uptake; essential lifesaving medicine for type 1 diabetes and advanced type 2 diabetes.

Evidence
Strong Evidence
Status · U.S.
Approved Medicine
MetabolicView profile
FDA source for Insulin ↗
Growth hormone secretagogue (GHSR agonist)
Conceptual molecular chain above a blue and violet network.

Ipamorelin

Also known as NNC 26-0161

Selective pentapeptide ghrelin receptor agonist stimulating pulsatile pituitary growth hormone release without significant cortisol elevation.

Evidence
Early Human Evidence
Status · U.S.
Unapproved
Growth Hormone AxisView profile
Endogenous reproductive neuropeptide hormone
Conceptual blue molecular chain on a pale background.

Kisspeptin

Also known as Kisspeptin-10, Kisspeptin-54, Metastin, KP-10, KISS1-derived peptides

Natural hormone that switches on the reproductive axis. Small phase 2 IVF studies used it to trigger egg maturation; no kisspeptin product is approved.

Evidence
Early Human Evidence
Status · U.S.
Investigational
ReproductiveView profile
Synthetic anti-inflammatory tripeptide
Conceptual molecular network among colorful cellular forms.

KPV

Also known as Lys-Pro-Val, alpha-MSH (11-13)

The C-terminal tripeptide fragment of alpha-melanocyte-stimulating hormone; studied in preclinical colitis models for NF-kappaB inhibition.

Evidence
Preclinical Evidence
Status · U.S.
Unapproved
FDA-approved peptide medicine
Conceptual molecular chain crossing a pale tissue-like landscape.

Lanreotide

Also known as Somatuline, Somatuline Depot, BIM-23014

Long-acting somatostatin analogue approved for long-term acromegaly therapy and progression-free survival prolongation in gastroenteropancreatic NETs.

Evidence
Strong Evidence
Status · U.S.
Approved Medicine
Growth Hormone AxisView profile
FDA source for Lanreotide ↗
Investigational oral tight-junction regulator peptide
Conceptual protein helix surrounded by luminous cellular patterns.

Larazotide

Also known as Larazotide acetate, AT-1001, AT1001

Oral gut-barrier peptide tested in celiac disease. Phase 2 results were mixed and the phase 3 trial was terminated by its sponsor in 2022.

Evidence
Early Human Evidence
Status · U.S.
Investigational
FDA-approved peptide medicine
Conceptual protein helix surrounded by luminous cellular patterns.

Liraglutide

Also known as Victoza, Saxenda

Once-daily GLP-1 receptor agonist approved for type 2 diabetes and chronic weight management, with extensive long-term cardiovascular outcome trial data.

Evidence
Strong Evidence
Status · U.S.
Approved Medicine
MetabolicView profile
FDA source for Liraglutide ↗
FDA-approved GLP-1 receptor agonist (U.S. supply now only in the Soliqua combination)
Conceptual violet protein ribbon amid flowing light patterns.

Lixisenatide

Also known as Adlyxin, Lyxumia, AVE0010, Soliqua 100/33

Once-daily GLP-1 receptor agonist for type 2 diabetes. Standalone Adlyxin is no longer marketed in the U.S.; lixisenatide remains available in Soliqua 100/33.

Evidence
Strong Evidence
Status · U.S.
Approved Medicine
MetabolicView profile
FDA source for Lixisenatide ↗
Human cathelicidin antimicrobial peptide
Conceptual colorful molecular chains near a cell membrane.

LL-37

Also known as Cathelicidin antimicrobial peptide, hCAP-18 fragment

Endogenous 37-amino-acid amphipathic peptide providing innate mucosal defense; evaluated in early human trials for venous leg ulcer healing.

Evidence
Early Human Evidence
Status · U.S.
Investigational
Cosmetic lipopeptide ingredient (not a drug)
Conceptual multicolored protein ribbon among molecular forms.

Matrixyl

Also known as Palmitoyl Pentapeptide-4, Pal-KTTKS, Palmitoyl Pentapeptide-3

Palmitoyl pentapeptide-4, a collagen-fragment cosmetic peptide. Small, mostly industry-run skin studies; not an FDA-approved drug.

Evidence
Early Human Evidence
Status · U.S.
Unapproved
Skin & HairView profile
Investigational in the U.S.; approved in China
Conceptual blue molecular chain on a pale background.

Mazdutide

Also known as IBI362, LY3305677

A once-weekly GLP-1/glucagon dual agonist approved in China in 2025 for weight management and type 2 diabetes. Investigational and not FDA-approved in the U.S.

Evidence
Moderate Evidence
Status · U.S.
Investigational
MetabolicView profile
Unapproved synthetic melanocortin receptor agonist
Conceptual blue molecular forms above a tissue-like surface.

Melanotan II

Also known as MT-II, Melanotan-II

Unapproved melanocortin agonist sold online for tanning. Only tiny 1990s human studies; case reports link it to melanoma, mole changes and priapism.

Evidence
Early Human Evidence
Status · U.S.
Unapproved
Skin & HairView profile
Mitochondrial-derived peptide
Conceptual molecular chains surrounding softly colored cells.

MOTS-c

Also known as Mitochondrial open reading frame of the 12S rRNA type-c

A 16-amino-acid peptide encoded within mitochondrial DNA; studied in preclinical rodent models for metabolic homeostasis and AMPK activation.

Evidence
Preclinical Evidence
Status · U.S.
Unapproved
LongevityView profile
FDA-approved peptide medicine
Conceptual multicolored protein ribbon among green cellular forms.

Octreotide

Also known as Sandostatin, Sandostatin LAR, SMS 201-995

Synthetic cyclic somatostatin octapeptide analogue approved for acromegaly, severe diarrhea associated with metastatic carcinoid tumors, and VIPomas.

Evidence
Strong Evidence
Status · U.S.
Approved Medicine
Growth Hormone AxisView profile
FDA source for Octreotide ↗
FDA-approved peptide medicine / Endogenous hormone
Conceptual violet protein ribbon amid flowing light patterns.

Oxytocin

Also known as Pitocin, Syntocinon, alpha-hypophamine

Endogenous nonapeptide neurohypophysial hormone and FDA-approved medicine for medical labor induction and postpartum uterine hemorrhage control.

Evidence
Strong Evidence
Status · U.S.
Approved Medicine
ReproductiveView profile
FDA source for Oxytocin ↗
Investigational peptide medicine
Conceptual protein forms around a cellular membrane.

Pemvidutide

Also known as ALT-801

An investigational once-weekly GLP-1/glucagon dual agonist from Altimmune. Phase 2 trials show liver-fat reduction and MASH resolution; a phase 3 MASH trial is recruiting.

Evidence
Early Human Evidence
Status · U.S.
Investigational
MetabolicView profile
Endogenous satiety peptide hormone
Conceptual molecular chains surrounding softly colored cells.

Peptide YY

Also known as PYY, PYY (3-36), Pancreatic Peptide YY3-36

Postprandially secreted enteroendocrine L-cell peptide that acts as an ileal brake via central Y2 receptors to suppress appetite and slow gastric emptying.

Evidence
Moderate Evidence
Status · U.S.
Investigational
MetabolicView profile
FDA-approved peptide medicine
Conceptual blue molecular chain on a pale background.

Pramlintide

Also known as Symlin, SymlinPen

FDA-approved synthetic analogue of human amylin used as mealtime adjunct therapy with insulin for glycemic regulation in type 1 and type 2 diabetes.

Evidence
Strong Evidence
Status · U.S.
Approved Medicine
MetabolicView profile
FDA source for Pramlintide ↗
Investigational peptide medicine
Conceptual multicolored protein ribbon among molecular forms.

Retatrutide

Also known as LY3437943

An investigational once-weekly GIP, GLP-1 and glucagon receptor agonist from Eli Lilly. Phase 3 obesity and diabetes trials report large weight loss; not FDA-approved.

Evidence
Moderate Evidence
Status · U.S.
Investigational
MetabolicView profile
Synthetic regulatory neuropeptide
Conceptual glowing cell-like branches and molecular connections.

Selank

Also known as Tuftsin analogue TP-7, Thr-Lys-Pro-Arg-Pro-Gly-Pro

Synthetic heptapeptide tuftsin derivative studied in Russian clinical cohorts for generalized anxiety disorder; unapproved in the US and Europe.

Evidence
Early Human Evidence
Status · U.S.
Unapproved
NeuropeptideView profile
FDA-approved peptide medicine
Conceptual coral protein ribbon above pale cellular forms.

Semaglutide

Also known as Ozempic, Wegovy, Rybelsus

Long-acting GLP-1 receptor agonist proven in large Phase 3 RCTs for type 2 diabetes glycemic control, obesity weight reduction, and cardiovascular risk reduction.

Evidence
Strong Evidence
Status · U.S.
Approved Medicine
MetabolicView profile
FDA source for Semaglutide ↗
Synthetic regulatory neuropeptide
Conceptual molecules beside a glowing network of cell-like branches.

Semax

Also known as Heptapeptide Semax, ACTH (4-7) Pro-Gly-Pro

Synthetic ACTH fragment analogue developed and clinically registered in Russia for stroke and cognitive recovery; unapproved by FDA or EMA.

Evidence
Early Human Evidence
Status · U.S.
Unapproved
NeuropeptideView profile
Discontinued FDA-approved GHRH analogue
Conceptual colorful molecular chains near a cell membrane.

Sermorelin

Also known as Geref, GHRH(1-29)NH2, GRF(1-29)NH2

A 29-amino-acid fragment of GHRH. It was FDA-approved as Geref for pediatric GH deficiency and testing, then discontinued in 2008 for reasons unrelated to safety.

Evidence
Moderate Evidence
Status · U.S.
Unapproved
Growth Hormone AxisView profile
FDA-approved MC4 receptor agonist for rare genetic and hypothalamic obesity
Conceptual molecular network among colorful cellular forms.

Setmelanotide

Also known as Imcivree, RM-493

MC4 receptor agonist (Imcivree) approved only for obesity from POMC, PCSK1 or LEPR deficiency, Bardet-Biedl syndrome or acquired hypothalamic obesity.

Evidence
Moderate Evidence
Status · U.S.
Approved Medicine
MetabolicView profile
FDA source for Setmelanotide ↗
Cosmetic peptide ingredient (not a drug)
Conceptual protein helix surrounded by luminous cellular patterns.

SNAP-8

Also known as Acetyl Octapeptide-3, Acetyl Glutamyl Heptapeptide-3, Acetyl Octapeptide-1

Acetyl octapeptide-3, a longer Argireline-type cosmetic peptide. Efficacy claims rest on supplier data; no standalone peer-reviewed human trials.

Evidence
Insufficient Evidence
Status · U.S.
Unapproved
Skin & HairView profile
Investigational peptide medicine
Conceptual protein helix surrounded by luminous cellular patterns.

Survodutide

Also known as BI 456906

An investigational once-weekly glucagon/GLP-1 receptor dual agonist from Boehringer Ingelheim, in phase 3 for obesity and MASH. Not FDA-approved.

Evidence
Moderate Evidence
Status · U.S.
Investigational
MetabolicView profile
Synthetic research peptide
Conceptual blue molecular forms above a tissue-like surface.

TB-500

Also known as Thymosin Beta-4 fragment, Tβ4 fragment, LKKTETQ

Synthetic peptide fragment modeled on Thymosin Beta-4; investigated in preclinical assays for actin sequestering, angiogenesis, and cell migration.

Evidence
Preclinical Evidence
Status · U.S.
Unapproved
Tissue RepairView profile
FDA-approved peptide medicine
Conceptual molecular chain above a blue cellular landscape.

Teriparatide

Also known as Forteo, rhPTH (1-34)

Recombinant human parathyroid hormone fragment (1-34) acting as an anabolic bone agent approved for severe osteoporosis with high fracture risk.

Evidence
Strong Evidence
Status · U.S.
Approved Medicine
Tissue RepairView profile
FDA source for Teriparatide ↗
FDA-approved peptide medicine
Conceptual colorful protein ribbons and molecular forms.

Tesamorelin

Also known as Egrifta, Egrifta SV, TH9507

FDA-approved stabilized GHRH analogue indicated for the reduction of excess visceral abdominal fat in HIV-associated lipodystrophy.

Evidence
Strong Evidence
Status · U.S.
Approved Medicine
Growth Hormone AxisView profile
FDA source for Tesamorelin ↗
Immunomodulatory peptide; prescription medicine in some countries, not FDA approved
Conceptual multicolored protein ribbon among molecular forms.

Thymosin Alpha-1

Also known as Thymalfasin, Zadaxin, Thymosin α1, Tα1, Ta1

Immune-signalling peptide sold as Zadaxin outside the U.S. A large sepsis trial found no survival benefit and hepatitis B evidence is low certainty.

Evidence
Moderate Evidence
Status · U.S.
Unapproved
FDA-approved peptide medicine
Conceptual multicolored protein ribbon among molecular forms.

Tirzepatide

Also known as Mounjaro, Zepbound, LY3298176

Dual GIP and GLP-1 receptor co-agonist approved by FDA for type 2 diabetes and chronic weight management following SURPASS and SURMOUNT clinical trials.

Evidence
Strong Evidence
Status · U.S.
Approved Medicine
MetabolicView profile
FDA source for Tirzepatide ↗
FDA-approved peptide medicine / Endogenous hormone
Conceptual molecular chain beside a blue cellular interface.

Vasopressin

Also known as Vasostrict, Arginine Vasopressin, AVP, Antidiuretic Hormone

Endogenous peptide hormone regulating osmotic balance and vascular resistance; FDA-approved for increasing blood pressure in vasodilatory shock.

Evidence
Strong Evidence
Status · U.S.
Approved Medicine
FDA source for Vasopressin ↗
Endogenous neuropeptide; investigational drug (aviptadil) in the U.S.
Conceptual molecular chain over warm flowing light patterns.

VIP (Vasoactive Intestinal Peptide)

Also known as Aviptadil, Vasoactive intestinal polypeptide, RLF-100, Zyesami, Invicorp (aviptadil with phentolamine)

Natural neuropeptide; its synthetic form aviptadil failed a phase 3 COVID-19 trial. Used with phentolamine for erectile dysfunction outside the U.S.

Evidence
Moderate Evidence
Status · U.S.
Investigational

Further reading on peptide research