Human Data vs Preclinical Data
The two evidence categories are not interchangeable. This page lays out, in a comparison table, what each can and cannot establish.
Educational research-literacy content only. Not medical advice, not dosing guidance, not sourcing advice, and not a protocol for human or animal use. See our responsible information policy.
| Question | Preclinical | Human |
|---|---|---|
| Does the compound bind a receptor? | Yes | Usually unnecessary |
| Is there a measurable downstream effect? | Yes (in model) | Yes (in body) |
| Is the effect dose-related? | Yes (in model) | Yes (in body) |
| Does this dose work in humans? | No | Yes (if studied) |
| What is the human safety profile? | No | Partial |
| What is the long-term safety? | No | Usually no |
| Does it improve a clinical outcome? | No | Yes (if measured) |
| Is human translation likely? | Suggestive only | — |
The hierarchy is not optional
Human evidence wins. Preclinical evidence is essential for mechanism and for justifying a first-in-human trial — but it does not, by itself, establish that a compound works in humans or is safe in them.
Why “works in mice” is not a substitute
The translational failure rate from animal model to clinic is high. A compound that produces large effects in rodent models routinely produces small effects, no effects, or harms in humans. The fact that some peptides have crossed this gap (e.g. GLP-1 agonists) does not make the gap small for other peptides.
Pages on PeptideStacks are reviewed when relevant new evidence becomes available. If you spot an error or have new evidence to suggest, please use our corrections policy.