Peptides
Some peptides are medicines. Others are still being tested. Start with the basics, then explore the evidence for each one.
Peptide school.
What they are. What they do.
What to watch out for.
No science degree.
Latest peptide research
Updated67% of the BPC-157/TB-500/CJC-1295/ipamorelin literature is animal work; human effects are modest at best and mostly uncontrolled. (2026 Aug 11)
67% of the BPC-157/TB-500/CJC-1295/ipamorelin literature is animal work; human effects are modest at best and mostly uncontrolled. (2026 Aug 11)
7 RCTs, n=8,069: CagriSema beats semaglutide by 7.6 kg, cagrilintide by 9.2 kg, placebo by 14.0 kg. (2026 Aug 17)
n=80, 24 weeks: dulaglutide 0.75 mg weekly cut glycaemic variability (CV 39.45% to 35.05%) while insulin worsened it; effect size 1.69. (2026 Aug 19)
933 records screened, 20 studies included, only 2 RCTs and 54 total human participants; the laser-resurfacing RCT hit satisfaction (P=.04) but missed wrinkle reduction…
In vitro or mechanistic only
5-Amino-1MQ
A small-molecule NNMT inhibitor (not actually a peptide) popular in biohacking for muscle preservation. Zero human trials as of 2026.
In vitro or mechanistic only
AOD-9604 (hGH Fragment 176-191)
A synthetic fragment of human growth hormone marketed for fat loss. Phase 2b failed and the program was abandoned. Popularity surged after FDA Category 2 removal in April 2026.
In vitro or mechanistic only
BPC-157
A 15-amino-acid fragment derived from a protein found in gastric juice. Heavy animal-model evidence for tendon and gut repair, zero completed human RCTs.
In vitro or mechanistic only
CJC-1295
A GHRH analog engineered for a long half-life. Widely used in anti-aging clinics as a growth-hormone secretagogue. Died as a pharmaceutical program after a 2008 phase 2 death. Now a research chemical.
Medium human RCTs or systematic reviews
CagriSema (cagrilintide + semaglutide)
Novo Nordisk's dual amylin/GLP-1 co-formulation. Phase 3 showed 23% weight loss but failed to beat tirzepatide head-to-head. FDA submission pending.
n=1 self-experiments or animal studies
Cardiogen
The heart-targeted member of the Khavinson short peptide family. Cell culture and animal reports describe protective effects on myocardium; there is no human clinical trial evidence.
n=1 self-experiments or animal studies
Cartalax
A short synthetic tripeptide from the Khavinson bioregulator line, positioned for cartilage, joints and connective tissue. Everything published sits in cell culture and animal work; no human randomised trial exists.
In vitro or mechanistic only
Cerluten
A brain-derived peptide complex from the Khavinson group in Saint Petersburg. Marketed as a broad CNS bioregulator. Human evidence sits almost entirely inside a single Russian research lineage.
In vitro or mechanistic only
5-Amino-1MQ
A small-molecule NNMT inhibitor (not actually a peptide) popular in biohacking for muscle preservation. Zero human trials as of 2026.
In vitro or mechanistic only
AOD-9604 (hGH Fragment 176-191)
A synthetic fragment of human growth hormone marketed for fat loss. Phase 2b failed and the program was abandoned. Popularity surged after FDA Category 2 removal in April 2026.
In vitro or mechanistic only
BPC-157
A 15-amino-acid fragment derived from a protein found in gastric juice. Heavy animal-model evidence for tendon and gut repair, zero completed human RCTs.
In vitro or mechanistic only
CJC-1295
A GHRH analog engineered for a long half-life. Widely used in anti-aging clinics as a growth-hormone secretagogue. Died as a pharmaceutical program after a 2008 phase 2 death. Now a research chemical.
Medium human RCTs or systematic reviews
CagriSema (cagrilintide + semaglutide)
Novo Nordisk's dual amylin/GLP-1 co-formulation. Phase 3 showed 23% weight loss but failed to beat tirzepatide head-to-head. FDA submission pending.
n=1 self-experiments or animal studies
Cardiogen
The heart-targeted member of the Khavinson short peptide family. Cell culture and animal reports describe protective effects on myocardium; there is no human clinical trial evidence.
n=1 self-experiments or animal studies
Cartalax
A short synthetic tripeptide from the Khavinson bioregulator line, positioned for cartilage, joints and connective tissue. Everything published sits in cell culture and animal work; no human randomised trial exists.
In vitro or mechanistic only
Cerluten
A brain-derived peptide complex from the Khavinson group in Saint Petersburg. Marketed as a broad CNS bioregulator. Human evidence sits almost entirely inside a single Russian research lineage.
In vitro or mechanistic only
Cortagen
A synthetic tetrapeptide isolated from bovine cortex extracts. The purified form of the Cerluten tissue complex, with a specific epigenetic-modulation claim on aged lymphocytes.
Small human pilot studies or cohorts
DSIP
A naturally occurring nonapeptide isolated from rabbit brain in the 1970s and tested in small human insomnia studies in the 1980s. Real but dated human data, no modern trials, and its endogenous role remains unresolved.
Large human RCTs or meta-analyses
Dulaglutide
Weekly GLP-1 agonist (Trulicity). REWIND trial (N=9,901, 5.4-year follow-up) showed 12% MACE reduction, the first significant CV benefit in a primary-prevention-heavy population. Concerning muscle-loss signal in hemodialysis patients.
In vitro or mechanistic only
Endoluten
A pineal-derived peptide complex from the Khavinson group, considered the flagship of the bioregulator line. Aimed at circadian rhythm, sleep quality, and downstream endocrine balance.
In vitro or mechanistic only
Epitalon
A synthetic tetrapeptide isolated from bovine pineal extracts. The most-studied piece of the Khavinson program, with the most-cited claim in the field: telomerase activation in human cell cultures.
Large human RCTs or meta-analyses
Exenatide
The first GLP-1 agonist ever approved (FDA 2005). EXSCEL trial (N=14,752) showed CV safety but not superiority. Parkinson's phase 3 failed after promising phase 2 data. Modest weight loss compared to newer agents.
n=1 self-experiments or animal studies
FGL
A synthetic peptide copied from the fibroblast growth factor binding loop of the neural cell adhesion molecule. It acts as an FGFR agonist and has a substantial rodent literature on neurite outgrowth, synaptic plasticity and memory.
In vitro or mechanistic only
FOXO4-DRI
A synthetic senolytic peptide designed to disrupt the FOXO4-p53 interaction inside senescent cells. Aged-mouse data is real. Human trials do not exist. A 2023 Circulation paper flagged pulmonary hypertension risk in animals.
Medium human RCTs or systematic reviews
GHK-Cu
A copper-binding tripeptide that falls with age. Solid topical dermatology evidence for wound healing and skin repair. Systemic longevity claims remain speculative.
Small human pilot studies or cohorts
GHRP-2
A synthetic ghrelin receptor agonist that reliably raises growth hormone in humans and is used clinically as a diagnostic agent in Japan. Strong endocrine data, no longevity data, and prohibited in sport.
n=1 self-experiments or animal studies
Humanin
A mitochondrial-derived peptide that falls with age and correlates with insulin sensitivity and neuroprotection. The HNG analog is roughly 1000 times more potent than native humanin but has no completed human RCT.
n=1 self-experiments or animal studies
IGF-1 LR3
A modified, long-acting IGF-1 analogue engineered to evade binding proteins. Potent in animals and cell culture, used industrially in bioprocessing, and carrying the clearest mechanistic conflict with longevity biology of anything in this section.
In vitro or mechanistic only
Ipamorelin
A selective growth hormone releasing peptide (GHRP) that binds the ghrelin receptor. Cleaner side effect profile than earlier GHRPs. Widely paired with CJC-1295 in anti-aging clinics.
n=1 self-experiments or animal studies
KPV
The three C-terminal amino acids of alpha-MSH, isolated as an anti-inflammatory peptide. Preclinical evidence in colitis and dermatitis. Voted for the FDA 503A compounding list by the PCAC advisory panel in July 2026.
Small human pilot studies or cohorts
LL-37
The only cathelicidin antimicrobial peptide in humans, central to innate immunity. It has been tested in randomised human wound-healing trials, and it is also a recognised autoantigen in psoriasis, which makes the risk profile genuinely two-sided.
Large human RCTs or meta-analyses
Liraglutide
The earliest daily GLP-1 agonist. FDA-approved 2010 (Victoza) and 2014 (Saxenda). Smallest weight-loss magnitude of the four molecules. Longest real-world safety record. No dedicated body composition trial data found.
n=1 self-experiments or animal studies
MOTS-c
A 16-amino-acid peptide encoded inside the mitochondrial genome. Falling with age, restoring exercise capacity in aged mice, and now in early human observational work as an insulin-sensitizing agent.
Medium human RCTs or systematic reviews
Melanotan I
The only peptide in this section with a full regulatory approval. As afamelanotide it is an FDA- and EMA-authorised implant for erythropoietic protoporphyria; as grey-market Melanotan I it is used for tanning with none of the associated oversight.
In vitro or mechanistic only
Melanotan II
Unlicensed tanning peptide with escalating safety signals including a 2025 case of oral mucosal malignant melanoma. Deliberately excluded from 2026 FDA reclassification due to substantial safety concerns.
Large human RCTs or meta-analyses
Orforglipron
First oral non-peptide GLP-1 agonist, FDA-approved April 2026 as Foundayo. ATTAIN-1 (N=3,127) showed up to 11.2% weight loss. No cardiovascular outcomes trial completed yet.
n=1 self-experiments or animal studies
P21
A small synthetic peptide developed from the neurotrophic activity of Cerebrolysin and modelled on a CNTF fragment. It has an unusually deep rodent literature in Alzheimer models and, so far, no human trials at all.
n=1 self-experiments or animal studies
PE-22-28
A seven-residue analogue of spadin that blocks the TREK-1 potassium channel. Rodent data show rapid antidepressant-like effects and increased hippocampal neurogenesis; there are no human trials.
n=1 self-experiments or animal studies
PEG-MGF
A pegylated version of the E-peptide from the mechano growth factor splice variant of IGF-1, sold for muscle repair. The underlying MGF biology is real academic science; the pegylated consumer product has no published human data.
Medium human RCTs or systematic reviews
PT-141 (Bremelanotide, Vyleesi)
FDA-approved melanocortin-4 receptor agonist for acquired generalized HSDD in premenopausal women. Off-label male use rests on abandoned-program data.
In vitro or mechanistic only
Pinealon
A synthetic tripeptide derived from the pineal peptide fraction. Marketed as a CNS bioregulator. Distinct from Epitalon and Endoluten despite the shared pineal-derived origin.
In vitro or mechanistic only
Proxofim
A senolytic peptide marketed as an improved relative of FOXO4-DRI. Almost nothing about it exists in the peer-reviewed literature under this name, and what is known comes from the wider FOXO4-p53 research it borrows from.
Medium human RCTs or systematic reviews
Retatrutide
Triple hormone receptor agonist (GIP, GLP-1, glucagon) still in Phase 3. 28.3% weight loss at 80 weeks in TRIUMPH-1, up to 30.3% at 104 weeks. The most potent weight-loss agent studied in this comparison. Not yet approved anywhere.
Medium human RCTs or systematic reviews
SS-31
A four-amino-acid peptide that binds to cardiolipin on the inner mitochondrial membrane and appears to restore mitochondrial function. In late-stage clinical trials for rare mitochondrial diseases and heart failure.
Small human pilot studies or cohorts
Selank
A Russian synthetic tuftsin analog used clinically as a non-sedating anxiolytic. Raises GABA tone, BDNF, and enkephalin activity without benzodiazepine-style dependence.
Large human RCTs or meta-analyses
Semaglutide
The only GLP-1 agonist with a completed cardiovascular outcomes trial in non-diabetic patients. 14.9% weight loss in STEP 1, 20% MACE reduction in SELECT, but documented sarcopenia risk in older adults.
Small human pilot studies or cohorts
Semax
A Russian synthetic ACTH(4-10) analog used clinically for stroke recovery and ADHD. Raises BDNF and dopamine tone in prefrontal cortex. Approved in Russia, unlisted elsewhere.
Small human pilot studies or cohorts
Sermorelin
A 29-amino-acid fragment of GHRH that stimulates the pituitary to release growth hormone. FDA-approved in the 1990s for pediatric growth-hormone deficiency, later withdrawn from the US market as a branded drug but still legally compounded.
Medium human RCTs or systematic reviews
Survodutide
Investigational dual GLP-1/glucagon agonist, not yet approved. SYNCHRONIZE-1 (N=725) showed 16.6% weight loss with 63.1% liver fat reduction and lean mass largely preserved. 19% discontinuation rate from GI side effects.
In vitro or mechanistic only
TB-500
A synthetic peptide fragment of thymosin beta-4, an endogenous 43-amino-acid protein involved in actin regulation and tissue repair. Anecdotal wound-healing use, no completed human RCT.
Large human RCTs or meta-analyses
Tesamorelin
The only FDA-approved growth-hormone-releasing hormone analog for reducing visceral fat. Approved for HIV lipodystrophy. Now being tested for age-related visceral adiposity and NAFLD.
In vitro or mechanistic only
Thymalin
A thymus-derived peptide complex from the Khavinson group. Positioned as an immunomodulator for aging thymic involution. Cytomax-format precursor to the isolated dipeptide Thymogen.
Small human pilot studies or cohorts
Thymosin alpha-1
A 28-amino-acid peptide first isolated from the thymus gland. Approved in more than 30 countries outside the US for hepatitis B, hepatitis C, and adjunct cancer therapy. Never FDA-approved in the United States.
Large human RCTs or meta-analyses
Tirzepatide
Dual GIP and GLP-1 agonist with 22.5% weight loss in SURMOUNT-1. Fat mass reduction 3x greater than lean mass loss. No completed cardiovascular outcomes trial yet.
In vitro or mechanistic only
Vesugen
A synthetic tripeptide targeted at vascular endothelium. Purified from the Ventfort tissue complex. Small Russian trials link it to endothelial function and cognitive endpoints in older adults.