Guidance

Declaration of Helsinki and Clinical Trial Regulations alignment

Information on the alignment of the amended UK clinical trial legislation with the Declaration of Helsinki, prioritising UK law where conflicts arise.

Documents

Details

This guidance explains that compliance with the principles of the Declaration of Helsinki is required by the amendment of the Clinical Trials Regulation but that reference to a specific version of the Declaration is no longer stated.

The Regulations require that the principles of the Declaration of Helsinki must be complied with for all clinical trials except where this contravenes the requirements of the amended Regulations and examples of potential conflicts are given. Where a conflict arises the MHRA expects sponsors to prioritise compliance with UK law while documenting the rationale for deviation and any associated impact.

Updates to this page

Published 12 January 2026

Sign up for emails or print this page