The Medicines for Human Use (Clinical Trials) (Amendment) Regulations 2025 changes the constitution requirements for Research Ethics Committees (RECs) that review clinical trials of investigational medicinal products (CTIMPs) and how many members must be in attendance at full REC meetings.
Constitution of RECs
From 28 April 2026, each REC that reviews CTIMPs must have an appointed Chairperson and a minimum of 5 members in total (including the appointed Chairperson). We’ll continue to make sure that the number of committee members in all RECs is sufficient so that full meetings of the RECs are quorate.
The REC membership will collectively reflect the qualifications and experience to review the science, medical aspects, and ethics of research applications.
RECs will have at least 1 member who is a lay member (an individual who does not have a formal qualification related to, or professional experience in, the field of clinical research or healthcare). This will mean that the way RECs are constituted and operate will continue to align with international standards.
Attendance requirements for full meetings of the REC
While the intention will still be to arrange meetings with at least 7 REC members present, the regulations allow a decision to be issued if 5 members are present (including an appointed Chairperson and at least 1 lay member).
This adjustment makes sure RECs continue to align with the standards set by the International Council for Harmonisation Good Clinical Practice (ICH GCP) and will not compromise the quality of the REC's review of research applications.
RECs that review gene therapy trials
The 2025 regulations remove the ‘Gene Therapy Advisory Committee’ definition.
Although the definition has been removed, there will still be RECs within the UK with specific expertise in reviewing applications involving gene therapies, which sponsors should submit their application to.
If a sponsor does not specify that the trial is a gene or advanced therapy trial at the booking stage, this could result in delays due to the REC needing to obtain expert advice or needing to transfer the application.
All RECs that are flagged as being recognised to review applications involving gene therapies continue to be identified within our REC directory.
CTIMPs involving adults with incapacity in Scotland
As stated in the 2025 clinical trials regulations, the changes in REC constitution and meeting attendance requirements detailed on this page will not apply to RECs in Scotland that review CTIMPs involving adults lacking capacity.
RECs in Scotland that review CTIMPs involving adults lacking capacity will continue to operate under the Adults with Incapacity (Scotland) Act 2000.