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Academy · Research Writing · Regulatory writing · ICH Efficacy guidelines
ICH Efficacy Guidelines That Govern Clinical Trials
Of the four ICH categories, Efficacy (E) is the one that governs how a clinical trial is designed, run, monitored and reported — the category that matters most directly to a trial team’s day-to-day decisions.
Within the broader ICH family (covered in the full guide), these are the specific Efficacy guidelines that shape a clinical trial from design through reporting.
E6: Good Clinical Practice
E6(R3), adopted at Step 4 by ICH Regulatory Members on 6 January 2025, sets the ethical and operational standard for how a trial is run — informed consent, investigator responsibilities, monitoring, and now a risk-based, proportionate approach to trial quality rather than uniform procedure regardless of risk. See the full ICH guide for what changed in this revision and how it fits the other three ICH categories.
E9: Statistical Principles for Clinical Trials
E9 assigns responsibility for a trial’s statistical work to a qualified trial statistician and sets the principles for minimising bias and maximising precision in the analysis. See Pubrica’s full page on the biostatistician’s role for how this plays out across a trial’s lifecycle.
E3: Structure and Content of Clinical Study Reports
E3 sets out the expected structure for the clinical study report written once a trial ends — the document regulators actually review when deciding whether a drug’s efficacy and safety evidence supports approval, distinct from a journal manuscript reporting the same trial.
Summary of the Three ICH Efficacy Guidelines for Clinical Trials
| Guideline | Governs | Written/used |
|---|---|---|
| E6 (Good Clinical Practice) | Ethical and operational conduct — consent, investigator duties, monitoring | Throughout the trial |
| E9 (Statistical Principles) | The statistical design and analysis | From protocol through final analysis |
| E3 (Clinical Study Reports) | The structure of the report submitted to regulators | Once the trial ends |
References and Sources
- European Medicines Agency / ICH. "ICH E6(R3) Guideline for Good Clinical Practice." read 8 October 2026. Step 5, EMA adoption 12 Dec 2024 (Principles/Annex 1)
Each source carries the date it was last read. Where a standard moves, this article is revised rather than left up with a note.
How to Cite This Article
Pick your referencing style and copy it. Your university or target journal may vary the punctuation — check its guide if it has one.
Pubrica Academy. (2026, October 8). The ICH Efficacy Guidelines That Actually Govern a Clinical Trial. Pubrica. https://pubrica.com/services/medical-writing/ich-guidelines-clinical-trials-drug-development/
Pubrica Academy. “The ICH Efficacy Guidelines that Actually Govern a Clinical Trial.” Pubrica, 8 Oct. 2026, pubrica.com/services/medical-writing/ich-guidelines-clinical-trials-drug-development/.
Pubrica Academy (2026) The ICH Efficacy Guidelines That Actually Govern a Clinical Trial. Pubrica. Available at: https://pubrica.com/services/medical-writing/ich-guidelines-clinical-trials-drug-development/ (Accessed: 15 October 2026).
Pubrica Academy. “The ICH Efficacy Guidelines that Actually Govern a Clinical Trial.” Pubrica. October 8, 2026. https://pubrica.com/services/medical-writing/ich-guidelines-clinical-trials-drug-development/
Pubrica Academy, ‘The ICH Efficacy Guidelines That Actually Govern a Clinical Trial’ (Pubrica, 8 October 2026) <https://pubrica.com/services/medical-writing/ich-guidelines-clinical-trials-drug-development/> accessed 15 October 2026.
Pubrica Academy. The ICH Efficacy Guidelines That Actually Govern a Clinical Trial. [Internet]. Pubrica; 2026 Oct 8 [cited 2026 Oct 15]. Available from: https://pubrica.com/services/medical-writing/ich-guidelines-clinical-trials-drug-development/
Pubrica Academy, “The ICH Efficacy Guidelines That Actually Govern a Clinical Trial,” Pubrica, Oct. 8, 2026. [Online]. Available: https://pubrica.com/services/medical-writing/ich-guidelines-clinical-trials-drug-development/
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title = {The ICH Efficacy Guidelines That Actually Govern a Clinical Trial},
howpublished = {Pubrica},
year = {2026},
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note = {Accessed: <span data-cite-acc="iso">2026-10-15</span>}
}This article is written to be learned from. Cite it if you are referring to what it says; if you are using the evidence behind it, cite the sources listed above instead.
Pubrica AcademyWritten and maintained by Pubrica’s subject matter experts. Articles are revised when the underlying standards change, and each carries the date it was last checked.
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