Peptide Evidence Maturity Index

Every peptide graded on a 5-tier evidence scale using data from PubMed, ClinicalTrials.gov, OpenAlex, and FDA regulatory databases. Updated March 2026.

Evidence Tier Methodology

Tier 1 FDA Approved — FDA approved, extensive Phase III data, multiple RCTs

Tier 2 Phase II+ — Phase II+ human trials, controlled data available

Tier 3 Limited Data — Phase I or limited human data, predominantly case series

Tier 4 Preclinical — Primarily animal/in-vitro, minimal human data

Tier 5 Preclinical Only — Theoretical or strictly preclinical only

Peptide	Tier	Human Studies	RCTs	Total Trials	Active Trials	Citation Trend	FDA Status
Semaglutide	Tier 1	2,591	261	680	151	Accelerating	Approved (Ozempic/Wegovy). Compounding restricted/contested.
Oxytocin	Tier 1	1,000	100	0	3	Growing	Approved (obstetric indications, 1980s). Intranasal use is off-label. Eligible for compounding.
Tirzepatide	Tier 1	973	108	230	69	Accelerating	Approved (Mounjaro/Zepbound). Compounding restricted/contested.
Liraglutide	Tier 1	800	100	0	3	Accelerating	Approved (Victoza/Saxenda). Generic available Dec 2024. Eligible for compounding.
Gonadorelin	Tier 1	500	50	0	2	Stable	Approved (Factrel, Lutrepulse, 1982). Standard of care for TRT fertility preservation. Eligible for compounding.
Thymosin Alpha-1	Tier 1	400	50	63	11	Stable	FDA Orphan Drug Designation (not full approval). Banned from 503A compounding.
Pentosan Polysulfate	Tier 1	400	30	0	2	Stable	Approved (Elmiron, 1996). Interstitial cystitis. Maculopathy safety warning 2020. Eligible for compounding.
PCSK9 Inhibitors	Tier 1	200	50	0	0	Accelerating	Approved (Praluent/alirocumab 2015, Repatha/evolocumab 2015, Leqvio/inclisiran 2021). LDL reduction 50-60%. Prescription required.
Tesamorelin	Tier 1	80	15	0	5	Growing	Approved (Egrifta/Egrifta WR). HIV-associated lipodystrophy. Not eligible for compounding.
PT-141	Tier 1	60	20	10	8	Growing	Approved (Vyleesi, 2019). HSDD in premenopausal women. Eligible for compounding.
Insulin	Tier 1	0	500	0	3	Accelerating	Approved (15+ products). Life-sustaining. Not eligible for compounding.
Collagen Peptides	Tier 1	0	20	0	3	Growing	Dietary supplement (DSHEA). Not FDA-approved drug. No compounding restrictions.
NAC	Tier 1	0	100	0	3	Accelerating	Approved (Mucomyst, 1963; Acetadote, 2004). Acetaminophen antidote and mucolytic. Off-label uses extensive.
TB-500	Tier 2	572	7	16	1	Stable	Investigational. Often under thymosin beta-4 restrictions.
Cerebrolysin	Tier 2	337	61	42	3	Stable	Investigational/No FDA Status. Approved in EU/Asia.
NAD+ Precursors	Tier 2	100	20	0	3	Growing	Dietary supplement (NMN/NR). No FDA drug approval. NMN regulatory status under review. Eligible for compounding.
GHK-Cu	Tier 2	60	2	2	1	Stable	Cosmetic/No FDA Status. Generally safe for topical.
Kisspeptin	Tier 2	50	10	0	3	Growing	Investigational (Phase 2). Not FDA approved. Not eligible for compounding. Expected approval 2027-2028.
Sermorelin	Tier 2	50	10	0	0	Stable	Was FDA approved 1997, discontinued 2008 (commercial, not safety). Compounded formulation legal. Category 2.
BPC-157	Tier 2	47	0	2	1	Stable	Not FDA Approved. Banned from 503A/503B (Sept 2023).
Taltirelin	Tier 2	45	4	4	0	Stable	Not FDA Approved (Approved in Japan as Ceredist). TRH analog for spinocerebellar ataxia. Not available in US/EU.
Selank	Tier 2	44	3	10	0	Growing	No FDA Status. Approved in Russia.
CJC-1295 + Ipamorelin Stack	Tier 2	39	3	0	0	Stable	Investigational. No FDA approval for either compound. Both restricted under Category 2 compounding guidance.
MK-677	Tier 2	30	10	0	0	Stable	Investigational. Oral GH secretagogue (small molecule). Category 2. Not on FDA banned list — compounding available.
Ipamorelin	Tier 2	23	2	2	0	Stable	Investigational. Category 2 (under scrutiny). Compounding under review.
CJC-1295	Tier 2	16	1	1	0	Stable	Investigational. No FDA Status.
Retatrutide	Tier 2	10	8	0	8	Accelerating	Investigational (Phase 3). TRIUMPH program. Expected FDA approval 2026-2027. Compounding ineligible.
CagriSema	Tier 2	0	10	10	1	Accelerating	Investigational. NDA under review (submitted Q3 2025). Expected approval Q2-Q3 2026.
Survodutide	Tier 2	0	6	15	1	Accelerating	Investigational (Phase 3 complete). FDA submission expected 2025-2026. Not eligible for compounding.
Orforglipron	Tier 2	0	10	10	1	Accelerating	Investigational (Phase 3 complete). ATTAIN program. Expected FDA approval Q4 2025-Q1 2026.
Danuglipron	Tier 2	0	6	4	0	Accelerating	Investigational (not FDA approved). Oral small-molecule GLP-1 agonist. Pfizer Phase 3 prep (once-daily formulation). Not eligible for compounding.
Ecnoglutide	Tier 2	0	4	4	0	Accelerating	Not FDA approved (approved in China NMPA). GLP-1 receptor agonist. Phase 3 complete in China. No US regulatory submission as of March 2026.
Efinopegdutide	Tier 2	0	3	3	2	Growing	Investigational (not FDA approved). GLP-1/glucagon dual agonist. Phase 2 ongoing (NAFLD/MASH). Merck/Hanmi development. Fast Track candidate.
Mazdutide	Tier 2	0	7	0	0	Accelerating	Approved in China (NMPA, Sept 2025) for T2D. NOT FDA approved. GLP-1/glucagon dual agonist. World's first approved GCG/GLP-1 dual agonist. No US filing.
Pemvidutide	Tier 2	0	4	4	2	Accelerating	Investigational (not FDA approved). GLP-1/glucagon dual agonist. FDA Fast Track (MASH). Phase 2b complete; Phase 3 planned. Altimmune development.
SS-31 (Elamipretide)	Tier 2	0	6	0	2	Growing	Investigational. Breakthrough Therapy Designation (HFpEF, 2019). Phase 3 ongoing. Not available outside trials.
Glutathione Injectable	Tier 2	0	35	0	2	Growing	Not FDA approved as drug. Available via 503B compounding. Approved for skin lightening in Japan/Korea.
Creatine Peptides	Tier 2	0	15	0	2	Stable	Dietary supplement. Not FDA-approved drug. No compounding restrictions.
Argireline	Tier 2	0	8	0	0	Stable	Cosmetic ingredient. No FDA pre-market approval. Approved in EU and UK.
Matrixyl	Tier 2	0	10	0	0	Stable	Cosmetic ingredient (palmitoyl pentapeptide-4). No FDA pre-market approval. Widely available OTC.
Semax	Tier 3	50	1	0	0	Stable	No FDA Status. Approved in Russia.
Epitalon	Tier 3	35	0	0	0	Stable	No FDA Status. Preclinical/Russian origin.
AOD-9604	Tier 3	13	0	0	0	Stable	No FDA Status. Some GRAS status.
GHK (peptide)	Tier 3	0	0	0	0	Stable	No FDA drug approval. Research use only. Most human data is for GHK-Cu (copper-bound form); copper-free GHK has zero confirmed human RCTs.
Snap-8	Tier 3	0	0	0	0	Stable	Cosmetic ingredient. No FDA pre-market approval. Approved for cosmetic use in EU. Zero peer-reviewed human RCTs.
Humanin	Tier 4	8	0	0	0	Growing	Not FDA approved. No therapeutic clinical trials. All human studies measure endogenous Humanin as biomarker only. Research use only.
Cortistatin	Tier 4	6	0	0	0	Stable	Not FDA approved. No human clinical trials. All human data is basic science (endogenous cortistatin measurement only). Research use only.
DSIP	Tier 4	5	3	0	0	Stable	Not FDA approved. No FDA Category designation. Research chemical only.
AHK-Cu	Tier 4	0	0	0	0	Stable	Cosmetic ingredient only. Not FDA approved as drug. EU cosmetic use approved. Zero human RCTs; single ex vivo hair follicle study only.
GnIH	Tier 4	0	0	0	0	Stable	No FDA status. Zero human clinical trials. Research use only. Not available commercially. Post-mortem tissue data only.
Thymalin	Tier 4	0	2	0	0	Stable	Not FDA approved. Not available in US/Western markets. Approved in Russia. 1-3 low-quality Russian RCTs; zero Western RCTs or active trials.
Crystallin	Tier 5	15	0	0	0	Stable	Not FDA approved. Not a therapeutic. Biomarker protein only (HSPB5/alpha-crystallin). Has never been administered therapeutically to humans. No drug development program.
5-Amino-1MQ	Tier 5	0	0	0	0	Stable	No FDA Status. Preclinical only.
PE-22-28	Tier 5	0	0	0	0	Stable	No FDA status. Preclinical only. Zero human studies. TREK-1 channel modulator. No development program, no investment.
Pinealon	Tier 5	0	0	0	0	Stable	No FDA Status. Preclinical only. Russian research. Saint Petersburg Institute of Bioregulation and Gerontology.
Vilon	Tier 5	0	0	0	0	Stable	No FDA Status. Preclinical only. Russian research. Saint Petersburg Institute of Bioregulation and Gerontology.
Cartalax	Tier 5	0	0	0	0	Stable	No FDA Status. Preclinical only. Russian research. Saint Petersburg Institute of Bioregulation and Gerontology.
Livagen	Tier 5	0	0	0	0	Stable	No FDA Status. Preclinical only. Russian research. Saint Petersburg Institute of Bioregulation and Gerontology.
Testagen	Tier 5	0	0	0	0	Stable	No FDA Status. Preclinical only. Russian research. Saint Petersburg Institute of Bioregulation and Gerontology.
Vesilute	Tier 5	0	0	0	0	Stable	No FDA Status. Preclinical only. Russian research. Saint Petersburg Institute of Bioregulation and Gerontology.
Pancragen	Tier 5	0	0	0	0	Stable	No FDA Status. Preclinical only. Russian research. Saint Petersburg Institute of Bioregulation and Gerontology.
Chonluten	Tier 5	0	0	0	0	Stable	No FDA Status. Preclinical only. Russian research. Saint Petersburg Institute of Bioregulation and Gerontology.

Click any column header to sort. Default: most credible first.

Data Sources

Data sourced programmatically from PubMed (human study counts), ClinicalTrials.gov (trial registry), OpenAlex (citation velocity analysis), and FDA regulatory databases. Analysis conducted using K-Dense Web scientific research platform with programmatic queries against PubMed, ClinicalTrials.gov, OpenAlex, and FDA databases. Last updated: March 2026.

About These Grades

Evidence tiers are assigned based on the highest level of clinical evidence available, not on therapeutic promise or popular demand. A peptide at Tier 3 may have significant preclinical potential but lacks the human trial data to support a higher classification.

For full methodology, see our evidence grading methodology.