Changes to the UK’s Clinical Trials regulatory regime become law

Overview

Long-awaited amendments to the UK’s clinical trials regulatory regime were signed into law on 28 April 2025, and will take effect on 28 April 2026 following a 12-month transition period. This legislative refresh was first mooted by the government in January 2022, when the Medicines and Healthcare products Regulatory Agency (the MHRA) and the Department of Health in Northern Ireland, conducted a public consultation on plans to improve and strengthen the UK clinical trials regulations, in order to “help make the UK the best place to research and develop safe and innovative medicines”. Parliament’s recent nod of approval marks a major milestone and confirms the UK’s biggest overhaul of the clinical trial regulations in 20-years.

The backdrop to these changes is the fact that the current UK requirements are based upon the now-repealed EU Clinical Trials Directive (2001/20/EC) (the EU CTD) which has since been replaced at EU-level by the European Clinical Trials Regulation (Regulation EU No 536/2014) (the EU CTR). Since the UK left the EU prior to the date on which the EU CTR took effect, the UK legal framework did not benefit from the same refresh as occurred at EU level and there has therefore been a need to update the legislation post-Brexit to ensure the UK remains a competitive and relevant clinical trials destination.

Introduction

On 28 April 2025, the Medicines for Human Use (Clinical Trials) (Amendment) Regulations 2025 (the New UK CTR- see here) were approved by Parliament having passed through the affirmative procedure, the government using its powers to create secondary legislation under the Medicines and Medical Devices Act 2021. This refresh represents the UK government’s attempt to revamp the UK clinical trials regulatory framework to reflect advancements in the sector and to ensure the UK remains a competitive destination for clinical research in a post-Brexit world.

The UK regulatory framework is, at present, based largely on the EU CTD, which has been replaced and upgraded at EU level in the form of the EU CTR. However, the UK did not implement the EU CTR due to Brexit taking effect prior to the CTR’s effective date, and consequently, the UK regime has been somewhat out of sync with the EU framework and has, by common consensus, required a refresh to reflect progress in both medicine and technology. 

Parliament’s approval of these legislative changes follows a long journey, which included a public consultation held back in January 2022, in which the government sought the views of stakeholders on its proposed changes to the regulatory regime. In March 2023, the government confirmed that it would be bringing forward a number of changes to the clinical trials regulations, and having taken office in July 2024, the Labour government also confirmed that it endorsed the proposed changes. This followed Labour’s 2024 manifesto pledge to “maximise our potential to lead the world in clinical trials”.

Once in effect, the changes brought about by the New UK CTR will represent the most significant overhaul of the clinical trials regulatory regime in the UK for 20-years, with the government claiming they will “eliminate unnecessary duplication and accelerate approvals” and will ultimately “transform the environment for clinical trials in the UK”.

What’s new?

Introducing the draft legislation to the First Delegated Legislation Committee, Andrew Gwynne, Parliamentary Under-Secretary, framed the changes under five headlines themes, which are as follows:

Risk-proportionate regulation

The government claims that New UK CTR will empower researchers to adopt more appropriate approaches to clinical trials depending on the level of risk. One such example is to cement within legislation the concept of the “notifiable trial” whereby the MHRA may choose to approve the request for such a trial without further assessment (a notification scheme has been in place since October 2023 involving expedited review of the lowest risk Phase 3 and Phase 4 trials – see here). The definition of “notifiable trial” limits this authorisation route to only investigational medicinal products (IMPs) which pose no significant safety concerns (the sponsor having made reasonable enquires) and also applies a number of qualifying conditions, as well as exclusions (eg where the IMP is an ATMP or is used for the first time in humans).   

Future-proofing

The government claims that the New UK CTR will future-proof the regulatory regime and move away from a one-size-fits-all approach to regulating clinical trials. By stripping out granular requirements from the legal text and instead reflecting these in tailored guidance, it is claimed that the new regime will provide for greater flexibility and adaptability for future advancements.

International alignment

The government has confirmed that the UK will remain aligned with international standards, which will allow for data from UK trials to be accepted globally. The New UK CTR requires compliance with the overarching principles of good clinical practice (GCP) in order to align with the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines. This directly addresses concerns raised by a number of consultation respondents about the global acceptability of UK clinical trial data for marketing authorisations if the UK was inconsistent with international GCP standards. The more detailed ICH guidance is not however incorporated into the New UK CTR which seeks to ensure “the right balance of compliance with the core principles and flexibility for the principles to be applied proportionately to the specific trial”.

Cement the UK as a clinical trials destination

Streamlined processes are introduced in order to simplify clinical trial applications. These include the combined review, which whilst already available to applicants (see – here), will become cemented within the legislation going forward. This means that applicants will submit a single submission which will be reviewed in parallel by both the regulator and the research ethics committee, leading to a simplified application process and internationally competitive approval timelines. In exceptional circumstances, for example an urgent situation where it would be beneficial to progress one application ahead of the other, the New UK CTR leaves open the possibility for separate applications to be made if agreed in advance with the MHRA or research ethics committee.

Increased transparency

Recognising the principle that trusted information should be publicly available for the benefit of all, the New UK CTR requires registration of the clinical trial in a public registry and publication of a summary of the trial results within 12-months of the trial end. Further, the sponsor must offer to all participants a summary of the results written in a manner understandable to laypersons. This, it is argued by the government, will contribute to building public trust in research.  

Next steps

The New UK CTR comes into force 12 months after the day on which they were made, and the new provisions therefore becomes effective on 28 April 2026. As confirmed in this webinar, both the MHRA and HRA are already working together to product informative guidance on the new requirements, which will be cover the following themes:

• applying for clinical trial approval;
• applying to modify a trial;
• safety reporting;
• end of a trial;
• transitional arrangements; and
• transparency requirements and HRA guidance.