Direct comparison
GCP vs. GLP: What’s the Difference?
GCP governs human clinical trials (ICH E6); GLP governs nonclinical lab safety studies (21 CFR Part 58). Compare scope, regulation, and when each applies.
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How do GCP (ICH E6), GLP (21 CFR Part 58) compare side by side?
The table below compares GCP (ICH E6), GLP (21 CFR Part 58) across 10 procurement-relevant dimensions, from what it defines through typical order in development.
Side-by-side comparison
| Dimension | GCP (ICH E6) | GLP (21 CFR Part 58) |
|---|---|---|
| What it defines | How human clinical trials must be designed, conducted, monitored, and reported to protect participants and ensure reliable data | How nonclinical (animal/in-vitro) laboratory safety studies must be conducted and documented to support a regulatory submission |
| Governing regulation/guideline | ICH E6 (internationally harmonized guideline); implemented in the US via 21 CFR Parts 50, 56, and 312 | 21 CFR Part 58 — a single, self-contained FDA regulation |
| Study subjects | Human research participants | Animals, cell/tissue cultures, and other nonclinical test systems — no human subjects |
| Study stage | Clinical development — Phase 1 through Phase 4 | Preclinical/nonclinical development, before or alongside an IND |
| Primary purpose | Protect participant rights, safety, and welfare; ensure trial data are credible | Ensure the quality and integrity of nonclinical safety data |
| Core documentation | Protocol, informed consent forms, case report forms, investigator brochure, trial master file | Study protocol, SOPs, raw data records, Quality Assurance Unit reports, final study report |
| Oversight (US) | Institutional Review Board (IRB) plus sponsor/FDA monitoring | In-house Quality Assurance Unit (QAU) plus FDA facility inspection |
| Who must comply | Sponsors, investigators, clinical research coordinators, IRBs, CROs running human trials | Nonclinical laboratories, CROs, and sponsors conducting preclinical safety studies |
| International harmonization | Yes — ICH E6 harmonized across ICH regions; ISO 14155 covers GCP for device trials | Broadly consistent with OECD GLP Principles, though a separate framework from 21 CFR Part 58 |
| Typical order in development | Follows GLP nonclinical safety data; governs first-in-human dosing onward | Precedes or runs alongside early clinical development |
Common questions
Common questions about GCP (ICH E6) vs GLP (21 CFR Part 58)
Can a single study be governed by both GCP and GLP?
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No. The two frameworks are defined by mutually exclusive subject types — GLP explicitly excludes studies involving human subjects. A development program moves through both in sequence (GLP nonclinical studies, then GCP clinical trials), but an individual study is governed by one or the other.
Is GLP the same as GMP?
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No. GLP (21 CFR Part 58) governs nonclinical safety testing; GMP (21 CFR Parts 210/211) governs manufacturing of the drug product itself. See CASRAI’s GLP vs. GMP comparison for the full breakdown.
Does GCP have one single regulation the way GLP does?
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Not exactly. GLP is one self-contained FDA regulation (21 CFR Part 58). GCP in the US is assembled from several regulations — 21 CFR Parts 50, 56, and 312 — read together with the internationally harmonized ICH E6 guideline, rather than one standalone GCP regulation.
Who inspects for GCP and GLP compliance?
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FDA inspects both. Bioresearch Monitoring (BIMO) inspections cover GCP compliance at clinical investigator sites and IRBs, while separate FDA GLP inspections cover nonclinical testing facilities and their Quality Assurance Units.
