# Compare Research Peptides — peptidespodcast

> Side-by-side comparison of BPC-157, CJC-1295, Retatrutide, GHK-Cu, Thymosin Alpha-1, and NAD+: compound class, primary research area, evidence maturity, regulatory status, and WADA standing.

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

| Compound | Class | Primary research area | Human evidence | Regulatory status | WADA |
|---|---|---|---|---|---|
| **BPC-157** | Cytoprotective gastric pentadecapeptide | Tissue repair, angiogenesis, gut cytoprotection | 3 small pilots (2025 review) [2]; no large RCTs | Not approved anywhere; FDA identified as not eligible for 503A compounding | Prohibited (S0, non-approved substances) |
| **CJC-1295** | GHRH analog (long-acting) | GH/IGF-1 axis stimulation | Early PK studies in healthy adults [11][12]; no approved indication | Never approved; DAC program discontinued; not on 503A list | Prohibited (S2, peptide hormones) |
| **Retatrutide** | GIP/GLP-1/glucagon triple agonist | Obesity, type 2 diabetes, fatty liver | Phase 2 RCTs (338 adults obesity [16]; 281 T2D [17]; 98 MASLD [15]); Phase 3 ongoing | Investigational (Eli Lilly); not approved by FDA or any regulator as of 2026 | Not specifically prohibited (verify current WADA list) |
| **GHK-Cu** | Copper-binding tripeptide | Skin matrix remodeling, hair, wound healing | Small topical RCTs; 1 hair-loss RCT (n=45) [20]; ex vivo skin penetration [22] | Topical: legal cosmetic ingredient (US, EU). Injectable/systemic: unapproved research chemical | Not listed on WADA Prohibited List |
| **Thymosin Alpha-1** | Thymic immunomodulatory peptide | Immune reconstitution, chronic infection, sepsis, oncology adjuvant | Multiple RCTs; Phase 3 TESTS trial (n=1,106) null [23]; ETASS marginal [27] | Approved drug in 35+ countries; not FDA-approved for US marketing | Not 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 FDA | Not 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.

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An independent literature digest — summarizing published research on research peptides, nothing more, nothing less.