Experiments performed in a controlled environment outside a living organism, such as in cell cultures or test tubes. "In vitro only" evidence is insufficient to draw conclusions about effects in humans.
"In Vitro" is filed under Evidence & Research in the PeptideAtlas glossary, alongside 14 other terms in that group.
The term applies directly to 4 compound profiles here: KPV (evidence D), Matrixyl (evidence F), Tripeptide-29 (evidence F), PNC-27 (evidence D). Each profile states the strength of the human evidence rather than only what the compound is claimed to do.
2 other glossary entries refer to this term in their own definition, which is usually the fastest way to see how it is used in practice.
Experiments performed in living organisms, including animal models and human subjects. In vivo evidence is stronger than in vitro but animal results do not reliably predict human outcomes.
Research conducted before clinical trials in humans, including in vitro studies and animal models. Many peptide claims are based solely on preclinical data, which has a high failure rate when translated to humans.
A study where participants are randomly assigned to receive either the treatment or a control (placebo or standard care). The gold standard for establishing causality in medical research.
The first stage of clinical testing in humans, typically involving 20-100 healthy volunteers. Tests safety, dosage, and side effects. Most peptides in the research pipeline are at or before this stage.
Compounds where this applies: KPV, Matrixyl, Tripeptide-29, PNC-27.
Terms that reference this one: In Vivo, Preclinical.
More Evidence & Research terms: Randomized Controlled Trial (RCT), Phase I Trial, Phase II Trial, Phase III Trial, Systematic Review, Meta-Analysis, In Vivo, Preclinical, Placebo Effect, p-Value, Biomarker, Endpoint, Observational Study, Publication Bias.