ICH Guidelines Overview
What are ICH guidelines?
ICH guidelines are technical standards for human medicines. They are agreed jointly by regulators and the pharmaceutical industry through the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH), and each regulatory authority then puts them into effect in its own region. ICH says its purpose is achieved "through Technical Guidelines that are implemented by the regulatory authorities" (Overview of ICH, May 2025, p. 4).
Approach: I used ICH's own published documents: the Overview of ICH (May 2025) and the Articles of Association (approved 24 March 2025). I couldn't check our ICH guideline collection this time, so this answer comes from those official pages only.
The organisation
- ICH was founded in 1990. On 23 October 2015 it was reformed as a non-profit legal entity under Swiss law (Overview, p. 3). It is based in Geneva and works in English (Articles of Association, Art. 1).
- Purpose (Art. 2): to promote public health through international harmonisation of technical requirements. This is meant to help:
- bring new medicines in on time and keep approved ones available;
- avoid unnecessary duplicate clinical trials in humans;
- make the development, registration and manufacturing of safe, effective, high-quality medicines efficient and cost-effective;
- minimise animal testing without compromising safety and effectiveness.
- Members (as of May 2025): 23 in total (Overview, p. 5):
- Founding regulators: EC (Europe), MHLW/PMDA (Japan) and FDA (US)
- Founding industry members: EFPIA, JPMA and PhRMA
- Standing regulators: Swissmedic and Health Canada
- Other regulators: ANVISA, MHRA, NMPA, MFDS, COFEPRIS and others
- Industry members: BIO, Global Self-Care Federation and IGBA
- There are also 2 Standing Observers (WHO, IFPMA) and 41 Observers (p. 6).
The four guideline series As of May 2025 there were 78 guidelines (Overview, p. 11):
| Series | Number of guidelines |
|---|---|
| Q: Quality | 26 |
| S: Safety | 16 |
| E: Efficacy | 24 |
| M: Multidisciplinary | 12 |
ICH also maintains:
- the CTD/eCTD, which "brings together all Quality, Safety and Efficacy information in a common, harmonised format, accepted by regulators in all ICH regions" (p. 9);
- MedDRA, its standardised medical terminology (p. 10);
- the ESTRI electronic standards for transferring regulatory information (p. 11).
ICH lists Good Clinical Practice among its main successes: common GCP standards let clinical trials run in one ICH region be used in other ICH regions (p. 8). A regulator applying for membership must already have implemented at least Q1 (stability testing), Q7 (GMP for active pharmaceutical ingredients) and E6 (GCP) (p. 15).
How a guideline is made (the five-step process, pp. 18-20)
- Step 1: A working group prepares a consensus draft.
- Step 2: 2a, the Assembly members endorse the technical document; 2b, the regulatory members endorse the draft guideline.
- Step 3: ICH regulatory members run a public consultation. The step ends when the working group's regulatory experts reach consensus.
- Step 4: The regulatory members of the Assembly adopt the final harmonised guideline.
- Step 5: Each ICH regulatory member implements it in its own region.
The Assembly decides by consensus. If there is no consensus, it votes, and only regulatory members have the right to vote (p. 14).
If you name a specific guideline, such as one of the Q, S, E or M documents, I can pull its scope and key requirements.
How do regulators adopt them?
ICH guidelines have no legal force of their own. After the ICH regulatory members adopt a final text at Step 4, each authority puts it into effect through its own procedure at Step 5, normally by publishing it as one of its own guidance documents with its own reference number and effective date. ICH counts a guideline as "Implemented" when "the process of implementation is completed," a step it treats as "identical to step 5 of the ICH process"; the regulator "makes publicly available the final Guideline" (ICH 2024 implementation monitoring report, Appendix 1, p. 34).
Approach: I couldn't search our ICH guideline collection or Health Canada's guidance catalogue this time. This answer therefore comes from official ICH, EMA, FDA and Health Canada pages that I opened.
How it works in three regions
| Region | Mechanism | Example |
|---|---|---|
| EU (EC/EMA) | "Once an ICH guideline has been finalised, the CHMP is responsible for implementing it as a European guideline." It is then published among EMA's scientific guidelines (EMA ICH page). | ICH E6(R3) carries an EMA reference, EMA/CHMP/ICH/162879/2026, with dates for each stage. For the principles and Annex 1: CHMP adoption 25 May 2023, public consultation until 26 September 2023, final CHMP adoption 12 December 2024, in effect 23 July 2025. For Annex 2: final CHMP adoption 25 June 2026, in effect 15 January 2027 (EMA E6(R3) Step 5, p. 1). |
| US (FDA) | FDA issues the ICH text as its own guidance, with an FDA docket, under its usual guidance process. | E6(R3) is a "Final Level 1 Guidance" issued September 2025 under docket FDA-2023-D-1955 by CDER and CBER. FDA says it was "prepared under the auspices of" ICH (FDA E6(R3) page). |
| Canada (Health Canada) | Health Canada "solicits comments on draft (Step 2) guidelines" and sends them to the ICH working group. A final guideline is published with a covering notice and an effective date. That date "may at times be affected by the need to undertake certain activities including collateral guidance and policy work, training, staffing, business process changes and/or regulatory amendment." If no effective date can be set when the guideline is published, the notice and the title page say so (Health Canada ICH page). | Notices are titled "Notice - Adoption of ICH Guidance: …", for example E11. |
So regulators take part at two points. They comment on and consult on the Step 2 draft (the EU and Canada both do this), and then they adopt the final text at Step 4 and implement it at Step 5. As a result, the same guideline can come into force on different dates in different regions.
What ICH counts as proper adoption (2024 report, Appendix 1, pp. 34-35)
- Adequately implemented: all relevant elements of the guideline are followed, "preferably by referring to/implementing the original ICH Guideline text and/or translating" it. Extra national detail is acceptable only to clarify the guideline, and it "should not increase regulatory burden."
- Not adequately implemented: the regulator adds requirements without objective justification, leaves out elements without justification, or applies the guideline to a narrower range of products.
- Adherence: the regulator also has to apply the guideline consistently in practice. A guideline that has been adopted but isn't applied counts as a "lack of adherence."
- Not applicable: this is allowed with justification. For example, Q4B need not be implemented where a country has no pharmacopoeia of its own.
Expectations by membership tier (2024 report, p. 6)
- Tier 1 (Q1, Q7, E6): these must already be implemented by a regulator applying for membership (Overview of ICH, p. 15, cited in my previous answer).
- Tier 2 (E2A, E2B(R3), E2D, M1 (MedDRA), M4 (CTD)): these were assessed for the newer regulatory members.
- Tier 3: this covers 56 further guidelines.
How well it works in practice (2024 report, pp. 3, 7)
- ICH monitors implementation through independent surveys run by CIRS. In 2024, 19 authorities rated themselves and 26 companies gave their view.
- Among the newer members (ANVISA, COFEPRIS, EDA, HSA, MFDS, MHRA, NMPA, SFDA, TFDA and TITCK), implementation and adherence rose:
- Tier 2: 47% in 2019, 64% in 2021, 73% in 2024
- Tier 3: 70% in 2021, 79% in 2024
- For the founding and standing members (EC, FDA, Health Canada, MHLW/PMDA and Swissmedic), implementation of the selected new guidelines ranged from 86% to 100%. Adherence ranged from 28% to 86%, with E19, M10, Q13 and S1B(R1) the lowest.
I can also check how a particular guideline has been adopted in a given region (for example MHRA, PMDA or ANVISA), including its reference number and effective date.