The quality system (OECD; 21 CFR 58) governing non-clinical safety studies, organized around reconstructability — any study must be reproducible from its raw data.
GLP governs non-clinical safety studies — the toxicology and safety pharmacology work that supports permission to test a medicine in humans. Its organising principle is reconstructability: an independent reviewer must be able to take the raw data and rebuild the study and its conclusions completely. Everything in the system exists to serve that, which is why GLP is a data-quality framework rather than a scientific-method one.
Three structural roles define it. The Study Director is the single point of study control, personally responsible for the conduct, interpretation, and reporting of the study. Test facility management provides resources and appoints the Study Director. And a Quality Assurance Unit — organisationally independent of the study staff — inspects the study and audits the final report against the raw data, reporting to management rather than to the Study Director.
A common misconception is that GLP is a mark of scientific quality. It is not: GLP certifies that the study was conducted, recorded, and reported in a controlled and reconstructable way, not that it was well designed or that its conclusions are correct. Equally, GLP does not apply to clinical trials — that is GCP — nor to analysis of clinical-trial samples, which is where GCLP fills the gap.
- —Applies to non-clinical safety studies, not to clinical trials or routine QC testing.
- —Organising principle: reconstructability from the raw data.
- —Study Director is the single point of study control and is personally accountable.
- —An independent Quality Assurance Unit inspects studies and audits reports against raw data.
- —Requires a study plan, characterised test items, and archived records for defined periods.
- —GLP evidences control and traceability — not scientific merit or correct conclusions.
US: 21 CFR Part 58 (Good Laboratory Practice for Nonclinical Laboratory Studies); OECD Principles of Good Laboratory Practice (as revised, 1997) with the OECD Advisory Documents; EU Directives 2004/9/EC and 2004/10/EC.
Frequently asked questions
What does GLP stand for?
GLP stands for Good Laboratory Practice.
What is GLP?
The quality system (OECD; 21 CFR 58) governing non-clinical safety studies, organized around reconstructability — any study must be reproducible from its raw data.
Which regulations cover GLP?
US: 21 CFR Part 58 (Good Laboratory Practice for Nonclinical Laboratory Studies); OECD Principles of Good Laboratory Practice (as revised, 1997) with the OECD Advisory Documents; EU Directives 2004/9/EC and 2004/10/EC.
SPEQ decodes published regulatory concepts in plain language. Definitions are a practitioner reference, not legal or regulatory advice.
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