UK MHRA Guidance: Ending a Clinical Trial for Medicines in the UK

Sharan Murugan
Jul 18
4 min read

Ending a clinical trial is an important regulatory milestone that requires sponsors to meet specific notification, transparency, and reporting obligations. Properly closing a trial ensures that regulatory authorities are informed, trial results are made publicly available, and participants have access to understandable information about the research in which they participated.

The Medicines and Healthcare products Regulatory Agency (MHRA) has published the guidance Clinical Trials for Medicines: Ending a Clinical Trial, outlining the requirements for notifying authorities when a trial ends, publishing trial results, and managing the lapse of clinical trial approvals. The guidance reflects the amended UK Clinical Trials Regulations, which took full effect on 28 April 2026.

Why This Guidance Is Important

Clinical trial responsibilities do not end when the final participant completes the study. Sponsors must formally notify the relevant authorities and fulfil transparency requirements within defined regulatory timelines.

The guidance provides a clear framework for managing the end of a clinical trial and helps sponsors understand their obligations for trial closure, results publication, participant communication, and clinical trial approval expiry.

Legal Status of the Guidance

The guidance accompanies the Medicines for Human Use (Clinical Trials) Regulations 2004, as amended by the Medicines for Human Use (Clinical Trials) (Amendment) Regulations 2025. Investigators, sponsors, and organizations delegated to perform trial-related activities should be familiar with the relevant guidance and act accordingly to achieve and maintain regulatory compliance.

Notifying Authorities That a Clinical Trial Has Ended

Sponsors must provide written notification to the licensing authority when a clinical trial has ended, with notification also provided to the ethics committee. The requirement applies to the global end of the clinical trial.

The notification must be submitted within:

90 calendar days when the trial ends according to the date or event specified in the protocol.
15 calendar days when the trial is terminated prematurely.

Local end-of-trial declarations may be submitted voluntarily, but relevant safety updates and substantial modifications must generally continue until the global end-of-trial notification is received.

End-of-Trial Notification Process

For clinical trials approved through the combined review process, sponsors should submit the end-of-trial declaration through the Integrated Research Application System (IRAS). For trials approved through separate applications, the declaration should be submitted to the licensing authority through MHRA Submissions and separately to the ethics committee.

Where a trial is terminated prematurely, the licensing authority will review the end-of-trial declaration and may request additional information before confirming acceptance.

Publication of Clinical Trial Results

Transparency remains an important responsibility after a clinical trial concludes. Within 12 months from the day after the conclusion of the trial, sponsors must publish a summary of the results in the same public registry where the trial was originally registered.

Sponsors must also offer trial participants an accessible summary of the results.

Sponsors may apply to the Health Research Authority (HRA) for a deferral or waiver of one or both requirements before the 12-month deadline. Phase I clinical trials may qualify for an automatic deferral of up to 30 months, which may be extended upon request.

Where an approved publication deferral is in place, a confidential summary of trial results may still need to be provided to the licensing authority within 12 months of trial completion.

Specific requirements also apply to certain paediatric trials sponsored by UK marketing authorisation holders, where results must be submitted to the licensing authority within six months of the trial ending.

Importance of Compliance With Transparency Requirements

Failure to comply with clinical trial results publication requirements may have broader regulatory consequences. The licensing authority may consider outstanding failures to meet transparency obligations when reviewing future clinical trial applications submitted by the same sponsor.

Sponsors should therefore incorporate results reporting and participant communication into their clinical trial closure processes rather than treating publication as a separate post-trial activity.

Lapse of Clinical Trial Approval

A clinical trial approval will lapse two years after the date of approval if no participants have been recruited into the UK trial.

The licensing authority monitors the approval status and will contact the sponsor if the approval lapses. The sponsor will then need to submit an end-of-trial notification.

To support this monitoring process, sponsors are required to notify the authorities of the date on which the first participant is recruited through the modification of an important detail process.

Applying for an Extension

Sponsors may request an extension before a clinical trial approval lapses by providing the authorities with the reason for the extension and the proposed duration.

The authorities may grant:

An initial extension of up to 36 months beyond the lapse date.
A further extension of up to 24 months, provided it is requested before the previous extension expires.

The authorities generally respond to extension requests within 30 calendar days or, where the trial is awaiting approval, alongside the clinical trial approval decision.

By integrating these requirements into clinical trial planning and close-out procedures, sponsors can maintain regulatory compliance, strengthen research transparency, and ensure that important clinical trial information is appropriately communicated to regulators, participants, and the public.