Good Laboratory Practice (GLP) is a quality system that regulates the organizational processes and conditions under which non-clinical safety studies are planned, performed, monitored, recorded, archived, and reported. GLP ensures that data from safety studies are complete, traceable, and reproducible, allowing regulators worldwide to rely on their quality. GLP is not a quality standard for clinical trials in humans – for which GCP applies – but exclusively for laboratory studies conducted as part of non-clinical safety assessment. Without GLP-compliant safety data, regulatory authorities generally do not accept applications for clinical trials or marketing authorizations, making GLP an indispensable component of all pharmaceutical development.
Legal Basis and International Framework
GLP was developed by the FDA in the 1970s following the discovery of data falsification in US laboratories and is now internationally harmonized through the OECD Principles of Good Laboratory Practice. In the EU, GLP has been transposed into national law by Directive 2004/10/EC. In Germany, the Chemicals Act, together with the GLP Ordinance, regulates its implementation. Studies conducted in compliance with GLP are mutually recognized by the regulatory authorities of OECD member states – a significant advantage for international development programs.
In Germany, the Federal Office of Consumer Protection and Food Safety (BVL) and the competent state authorities are responsible for monitoring GLP compliance. GLP-certified facilities are regularly inspected. A valid GLP certificate is a prerequisite for safety data from the facility to be submitted in marketing authorization dossiers. For pharmaceutical companies commissioning testing facilities for non-clinical studies, checking GLP certification is therefore an obligatory step in supplier qualification.
Scope: Which Studies Fall Under GLP?
GLP applies to non-clinical safety studies intended for submission to regulators as part of an approval process for medicinal products, plant protection products, chemicals, food additives, or biocides. Typical GLP studies include toxicology studies (acute, subchronic, and chronic toxicity), genotoxicity tests, reproductive toxicology, pharmacokinetic investigations in animals, and safety pharmacology. Pure research studies without a regulatory purpose and clinical studies in humans do not fall under GLP.
A common question in practice is whether a specific study must be conducted in compliance with GLP or if it is optional. The answer depends on whether the results are to be used in a regulatory dossier. If a study is cited in a marketing authorization submission, it must generally be GLP-compliant – unless the relevant regulator accepts justified exceptions. Early regulatory affairs advice clarifies this and avoids costly repeat studies. Furthermore, during study planning, it should be checked whether specific OECD test guidelines apply, as their correct application is also a prerequisite for the regulatory acceptance of the results.
Principles and Core Requirements
The OECD GLP Principles define requirements for organization and personnel, quality assurance, facilities, equipment and materials, test systems, test and reference items, standard operating procedures, study conduct, final report preparation, and archiving. An independent quality assurance unit within the testing facility is mandatory and regularly verifies that studies are conducted according to the protocol and GLP requirements. The study director bears overall scientific responsibility for each individual study.
Archiving requirements are particularly stringent: all raw data, protocols, final reports, and samples must be securely stored for the entire lifespan of the approved product – in some cases, for decades. For the sponsor, this means making arrangements for archive transfer in the event of a testing facility’s dissolution or transfer, to ensure permanent access to the original data. In practice, it is advisable to establish contractual agreements regarding archiving responsibility when commissioning the testing facility and to regularly verify that archiving conditions continue to meet requirements.
Distinction from GMP and GCP
The three major “Good Practice” standards have different scopes. GLP regulates non-clinical safety research in the laboratory. GMP regulates the manufacturing of medicinal products and investigational medicinal products. GCP regulates the conduct of clinical trials in humans. In pharmaceutical development, all three intertwine: GLP data provide the non-clinical safety basis, GMP ensures the quality of the investigational substance, and GCP regulates clinical use in patients. A sponsor must simultaneously consider all three standards and ensure that the applicable requirements are fully met in the respective studies. In practice, this means that when commissioning external service providers – be it a testing facility for GLP studies, a contract manufacturer for GMP-compliant investigational products, or a CRO for GCP studies – the applicable standard must be contractually defined, regularly audited, and demonstrated during regulatory inspections. Full-service CROs like mediconomics assist sponsors in coordinating the management of all three levels and identifying regulatory gaps early on.
Frequently Asked Questions (FAQ)
Does a toxicology study always have to be GLP-compliant?
Only if the results are to be submitted in a regulatory marketing authorization dossier. Purely exploratory toxicology studies without a regulatory purpose can be conducted without GLP, but they have no evidential value in regulatory submissions.
What is the difference between GLP and ISO 17025?
ISO 17025 is a general accreditation standard for testing and calibration laboratories, setting requirements for technical competence and management systems. GLP is a regulatory defined standard specifically for non-clinical safety studies with regulatory relevance. Both standards can apply in parallel but have different focuses and auditing bodies.
What happens if a GLP study has deficiencies?
Depending on their severity, deficiencies can lead to the discrediting of the study’s GLP compliance, rejection of data by regulators, or, in extreme cases, the initiation of criminal proceedings. For minor deviations, documented corrective actions may suffice; for serious deficiencies, the regulatory authority may require the study to be repeated.