GCLP

Good Clinical Laboratory Practice

GCLP fills a genuine gap between two regimes. GLP (21 CFR 58, OECD) governs non-clinical safety studies in animals and in vitro — it does not cover laboratories analysing samples from human trials. GCP governs the conduct of the trial itself but says relatively little about laboratory operations. A lab measuring a pharmacokinetic profile or a primary endpoint biomarker from trial participants therefore sits between the two, and GCLP applies GLP-grade discipline to that work.

In practice it means the things that make a laboratory result defensible: validated analytical methods, qualified and maintained equipment with calibration records, competent and trained staff, documented sample chain of custody from collection through storage to analysis, controlled reagents and reference standards, secure data handling with audit trails, and independent quality assurance oversight.

One point of care: GCLP is guidance, not a standalone binding regulation in the US or EU. Its authority comes indirectly — through GCP obligations for data reliability, through the sponsor’s duty to ensure trial data are credible, and through the regulator’s ability to inspect the labs that generated pivotal data. WHO published the widely used GCLP guidance in 2009; several national bodies and BARQA have issued comparable versions.

• —Fills the gap: GLP covers non-clinical studies; GCP covers trial conduct; GCLP covers labs analysing clinical-trial samples.
• —Core controls: validated methods, qualified equipment, trained staff, chain of custody, controlled reagents, secure data, QA oversight.
• —Guidance rather than a standalone binding regulation — its force comes via GCP data-reliability obligations.
• —Especially relevant to central and specialty labs generating pivotal endpoints and PK data.
• —Sample integrity (collection, storage temperature, transport, stability) is as decisive as the analysis itself.

WHO/TDR Good Clinical Laboratory Practice (2009); complemented in practice by ICH E6(R3) Good Clinical Practice (sponsor responsibility for data reliability) and, for non-clinical work, 21 CFR Part 58 / OECD GLP Principles. ISO 15189 applies to medical laboratories in a clinical-service context.