# Compare AOD-9604, Tirzepatide & MOTS-c — Zap Peptides

> Side-by-side comparison of AOD-9604, tirzepatide, and MOTS-c: mechanism class, evidence tier, regulatory status, and WADA classification. Zap Peptides research desk.

Three metabolic research peptides, three very different evidence profiles and regulatory statuses — calibrated across the same dimensions.

## The short version

This page sets the three compounds on this desk next to each other on the dimensions that matter most to a researcher evaluating the evidence base: mechanism class, what the compound is actually studied for, how mature the human evidence is, what regulatory category it falls into, and how anti-doping authorities classify it. The contrast is stark. Tirzepatide has a large Phase 3 RCT dataset and an FDA approval; AOD-9604 has human safety data but a null efficacy signal in a formal Phase IIb programme; MOTS-c has no human interventional data at all. They belong to the same thematic desk — metabolic regulation and body composition — but sit at completely different points on the evidence maturity curve.

## Comparison table

| Dimension | AOD-9604 | Tirzepatide | MOTS-c |
|---|---|---|---|
| **Molecule class** | Synthetic hGH C-terminal fragment (hexadecapeptide, 16 aa) | Synthetic dual incretin agonist (39 aa, fatty-diacid arm) | Mitochondrial-derived peptide (16 aa, MT-RNR1 encoded) |
| **Primary mechanism** | ACC inhibition → suppressed lipogenesis; beta3-AR upregulation → fat oxidation; GH-receptor-sparing | GIP + GLP-1 dual receptor agonism → insulin secretion, glucagon suppression, appetite reduction | Folate-cycle inhibition → AICAR accumulation → AMPK activation; stress-induced nuclear translocation via NRF2 |
| **What it is studied for** | Lipolysis and antilipogenesis; secondary: cartilage/OA (preclinical) | Type 2 diabetes (HbA1c); obesity (body weight); sleep apnea | Skeletal-muscle glucose handling; physical performance; aging/healthspan; metabolic stress response |
| **Evidence maturity — animal** | Strong: multiple mouse and rabbit models [4][5][6][7] | N/A (clinical drug) | Strong: aged-mouse performance [16], muscle atrophy prevention [13] |
| **Evidence maturity — human** | Phase IIb: **null result** for primary obesity endpoint; good safety/tolerability [3] | Phase 3 RCTs (n>4,000): −20.9% weight at 72 weeks [11]; superior HbA1c vs. incretin comparator [12] | Observational only: biomarker association in hemodialysis cohort (n=94) [14] |
| **Regulatory status** | Not approved (any jurisdiction). Phase IIb discontinued | **FDA-approved** (T2D, obesity, OSA). Prescription-only | Not approved. Research chemical only |
| **WADA status** | **Prohibited S2** at all times in sport | Not specifically prohibited (prescription drug) | **Prohibited** (peptide/metabolic-modulator category) at all times |
| **Human pharmacokinetics** | IV: ~3 min half-life [2]; subcutaneous PK not peer-reviewed | Well-characterized: ~5-day half-life, once-weekly dosing [9] | **Not established** in humans |
| **Main safety signal** | Null efficacy; no excess adverse events vs. placebo [3] | GI intolerance (dose-limiting); gallbladder/biliary disease RR 1.97 [10]; boxed MTC warning [9] | Unknown in humans; no interventional human data |

*All citations above are present in the shared [references list](/references).*

## Reading the evidence tiers

The table above encodes a crucial point that numbers alone can obscure: the same column category — "evidence maturity, human" — contains radically different types of human data across the three compounds.

For **tirzepatide**, human means three large Phase 3 double-blind or open-label RCTs with combined enrollment well above 4,000 participants, pre-specified primary endpoints, and independent adjudication — the gold standard of clinical evidence [8][11][12].

For **AOD-9604**, human means a completed Phase IIb programme of approximately 900 participants with a formally pre-specified primary endpoint of weight loss versus placebo — and a **negative result** [3]. The compound had its human test; it did not pass. That is a different evidence category than "never tested in humans."

For **MOTS-c**, human means a 94-person observational cohort measuring endogenous circulating levels — not exogenous administration — and an association with mortality outcomes [14]. No randomized assignment, no dose of the peptide was given to participants. The gap between this and an efficacy trial is substantial.

Researchers comparing the three should weight these distinctions heavily. A null Phase IIb is informative data; an observational biomarker association is a hypothesis generator, not efficacy evidence.

---

A numerically honest digest of the published evidence — effect sizes, study designs, and the gaps between them.