ICH E20 Public Consultation
Published 24 July 2025
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This publication is available at https://www.gov.uk/government/consultations/consultation-on-the-international-council-for-harmonisation-guideline-e20-for-adaptive-clinical-trial-design/ich-e20-public-consultation
There is an increasing interest in using adaptive clinical trials in modern drug development. Potential advantages of adaptive designs include limiting patient exposure to unsafe or ineffective treatments, savings of trial resources, and accelerating the development process while ensuring that the adaptive clinical trials can provide the evidence for regulatory decision making. However, there are uncertainties due to the lack of common principles for the design, conduct, analysis, and interpretation of adaptive clinical trials and the lack of common expectations for documentation to support regulatory review. To address this, a new guideline (E20) has been prepared by an Expert Working Group (EIWG) of the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH).
The ICH E20 guideline describes key principles for confirmatory trials with an adaptive design. These principles are critical to ensuring the trials produce reliable and interpretable information and require specific considerations with use of an adaptive design.
ICH E20 discusses five principles: Adequacy within the development program, Adequacy of trial planning, Limiting the chances of erroneous conclusions, Reliability of estimation, and Maintenance of trial integrity. These principles should also provide the flexibility to evaluate / discuss innovative approaches to clinical trial design throughout the development process.
The MHRA welcomes views on the draft guideline from all UK stakeholders including patients and the public. You can provide comments and recommendations to the consultation as an individual or on behalf of an organisation (one response per organisation please) using the ICH Public Consultation Comments template and emailing it to ichconsultations@mhra.gov.uk. Please include ‘E20 consultation’ in the subject line of your email.
Following the consultation, feedback from the stakeholders within the UK and other ICH regions will be reviewed and discussed by the ICH E20 EWG directly. We do not intend to publish a full response to this consultation, as we are not required to for this type of consultation.
Background
The Medicines and Healthcare products Regulatory Agency (MHRA) became a full member of International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) in May 2022. ICH brings together global regulators and the pharmaceutical industry to achieve the harmonised development of safe, effective and high-quality medicines.