REFERENCE

Six Research Compounds, Side by Side

A plain-English comparison table — class, mechanism, evidence level, and regulatory status at a glance.

The short version

These six compounds sit in very different places on the research spectrum. Retatrutide is deep in Phase 3 clinical trials with Phase 2 human data showing dramatic effects. BPC-157 has thirty years of rodent studies and almost no human data. Thymosin Alpha-1 is an approved drug in 35 countries whose best-powered Phase 3 trial just came back null. GHK-Cu has a long cosmetic safety record for topical use. CJC-1295 raised GH and IGF-1 in healthy adults but its drug development program was discontinued. NAD+ is a coenzyme whose precursors reliably raise blood levels in human trials, though hard clinical outcomes remain unproven. The table below gives you the key dimensions at a glance.

Comparison table

CompoundClassPrimary research areaHuman evidenceRegulatory statusWADA
BPC-157Cytoprotective gastric pentadecapeptideTissue repair, angiogenesis, gut cytoprotection3 small pilots (2025 review) [2]; no large RCTsNot approved anywhere; FDA identified as not eligible for 503A compoundingProhibited (S0, non-approved substances)
CJC-1295GHRH analog (long-acting)GH/IGF-1 axis stimulationEarly PK studies in healthy adults [11][12]; no approved indicationNever approved; DAC program discontinued; not on 503A listProhibited (S2, peptide hormones)
RetatrutideGIP/GLP-1/glucagon triple agonistObesity, type 2 diabetes, fatty liverPhase 2 RCTs (338 adults obesity [16]; 281 T2D [17]; 98 MASLD [15]); Phase 3 ongoingInvestigational (Eli Lilly); not approved by FDA or any regulator as of 2026Not specifically prohibited (verify current WADA list)
GHK-CuCopper-binding tripeptideSkin matrix remodeling, hair, wound healingSmall topical RCTs; 1 hair-loss RCT (n=45) [20]; ex vivo skin penetration [22]Topical: legal cosmetic ingredient (US, EU). Injectable/systemic: unapproved research chemicalNot listed on WADA Prohibited List
Thymosin Alpha-1Thymic immunomodulatory peptideImmune reconstitution, chronic infection, sepsis, oncology adjuvantMultiple RCTs; Phase 3 TESTS trial (n=1,106) null [23]; ETASS marginal [27]Approved drug in 35+ countries; not FDA-approved for US marketingNot specifically listed; unapproved peptide caution applies
NAD+Endogenous redox coenzyme (DietarySupplement framing)Energy metabolism, DNA repair, longevity (via NMN/NR precursors)Several RCTs of NMN/NR precursors [29][30][32]; limited on hard clinical outcomes [28]Not an approved drug; sold as dietary supplement; NMN supplement status contested by FDANot prohibited

Note: regulatory and WADA status can change. Verify current lists before relying on this table.

Reading the evidence maturity column

Preclinical / animal-dominant means the compound has been studied extensively in rodents or cells but human data are sparse. BPC-157 sits squarely here: decades of rat data, three small human pilots as of 2025 reviews [2]. Claims that translate animal findings directly to humans are not supported by the evidence.

Early human pharmacology means controlled human studies exist — often healthy volunteers, measuring pharmacokinetics, hormone levels, or biomarkers — but no outcome trials have been completed or the drug development program was discontinued. CJC-1295 is the clearest example: documented GH and IGF-1 elevation in healthy adults [11][12], no approved indication, discontinued development.

Phase 2 / late investigational means the compound has completed at least one controlled Phase 2 efficacy trial in the target population with meaningful endpoints. Retatrutide belongs here, with three Phase 2 trials reported and Phase 3 ongoing [13][16][17].

Approved with caveats means the compound is approved as a drug in one or more jurisdictions, but either the most rigorous trial data are now mixed (Thymosin Alpha-1) or the approved indication is narrow and other uses remain off-label or investigational.

Cosmetic / supplement evidence describes a compound with established safety in one context (topical use, oral supplement) and limited or absent human evidence for systemic or injectable use. GHK-Cu and NAD+ fall here depending on route and form.