Overview of ICH, FDA, EMA and WHO Guidelines

Part of Good Clinical Practice (GCP) — ICH E6(R3): Introduction to Clinical Research and GCP.

About 5 minutes. Free, in your language, no account needed.

Why this matters

Sites often assume that following ICH E6(R3) is enough. It is not. E6(R3) repeatedly defers to "applicable regulatory requirements", which means the law of the country where you work. If you cannot name which body sets which rule, you will either over-apply a foreign rule or miss a local one. Both create findings at inspection.

ICH: the harmonized standard

ICH is the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use. It brings regulatory authorities and industry together to write harmonized guidelines. A guideline that reaches Step 4 of the ICH process has been adopted as a harmonized text.

ICH E6(R3) is the Good Clinical Practice guideline. It has two parts in force at different times: the Principles with Annex 1, adopted 6 January 2025, and Annex 2, adopted 3 June 2026.

ICH itself does not inspect sites and does not issue penalties. An ICH guideline becomes enforceable only when a regulator adopts it into its own framework. This is the single most important point in this lesson.

E6(R3) states its own scope plainly:

"This guideline applies to interventional clinical trials of investigational products that are intended to be submitted to regulatory authorities."

E6(R3) also builds on other ICH guidelines rather than repeating them. It names ICH E8(R1) for general considerations and critical to quality factors, ICH E3 for clinical study reports, and ICH E2A for safety reporting.

FDA: the United States regulator

The Food and Drug Administration (FDA) regulates medicines, biologics and medical devices in the United States. It reviews investigational applications, inspects investigators and sponsors, and enforces United States regulations found in Title 21 of the Code of Federal Regulations.

The FDA is reported to have published final guidance adopting ICH E6(R3) on 8 September 2025. That date comes from a secondary source. No separate FDA compliance deadline has been announced. Confirm the current status in the FDA guidance register before you quote it to a sponsor.

Note that FDA guidance and FDA regulation are different things. Regulations bind. Guidance describes the agency's current thinking.

EMA: the European Union regulator

The European Medicines Agency (EMA) is the scientific agency of the European Union for medicines. It coordinates evaluation and safety monitoring. National competent authorities in each member state, and the European Commission, hold the enforcement and authorization powers.

Two European dates matter for GCP.

WHO: guidance and capacity for member states

The World Health Organization (WHO) is the United Nations agency for health. Its role in clinical research is different from that of FDA and EMA. WHO is not a medicines regulator for any country. It publishes guidance and technical documents that its member states may adopt, and it supports countries in strengthening national regulatory systems and research capacity.

For learners in countries without a large national regulator, WHO guidance is often the practical reference point, and the national authority may base its own rules on it.

Two cautions:

Which rule applies to you

Use this order of reasoning.

  1. Start with the protocol. It is the trial-specific rulebook and it must comply with the rest.
  2. Apply the applicable regulatory requirements of the country and, where relevant, the institution.
  3. Apply ICH E6(R3) as the GCP standard the protocol and the sponsor agreement commit you to.
  4. Where a national requirement is stricter than E6(R3), follow the stricter requirement.

E6(R3) supports this. It says the Annexes are not rigid, and that "various approaches to the provisions in the Annexes may be considered provided they are justified and achieve the intended purpose of the application of the principles."

In practice

ABC Pharmaceuticals runs a hypertension trial across Germany, the United States, Kenya and the Philippines. Ana, the coordinator at Dr. Sarah's site, receives one global protocol and one global monitoring plan.

Ana asks a good question: does she follow the sponsor's global safety reporting timeline, or her national one? The answer is both. The protocol states the timeline for reporting events to the sponsor. National law states what the sponsor and the site must report to the national authority and to the ethics committee. They are different obligations with different recipients.

Ana writes a one-page local requirements note for her site file. It lists the national authority, the ethics committee, the local reporting routes, and the language requirements for participant materials. She reviews it whenever the protocol is amended.

A harmonized guideline is a floor, not a ceiling. Local law can raise it.

Key takeaways