Guidance

Archiving and retention of clinical trial records

Updated 26 March 2026

Legal status of this guidance 

This guidance accompanies the Medicines for Human Use (Clinical Trials) Regulations 2004 (‘the Clinical Trials Regulations’), as amended by the Medicines for Human Use (Clinical Trials) (Amendment) Regulations 2025.These amendments come into force on 28 April 2026.

For assistance in determining whether a clinical trial is within the scope of these Regulations, refer to the Is it a clinical trial of a medicinal product? algorithm. 

Part 2 of Schedule 1 to the Clinical Trials Regulations requires that the investigator and sponsor have regard to all relevant guidance with respect to commencing and conducting a clinical trial.

Investigators and sponsors (and any individual or organisation that the sponsor delegates trial related activities to) must, therefore, ensure that they are fully aware of the information within this guidance and act accordingly to achieve and maintain regulatory compliance. 

Essential records definition 

The MHRA recognises the ICH GCP E6 (R3) definition of essential records (a review of the differences between ICGH E6 (R2) and ICH E6 (R3) can be found here and there are multiple entries for record keeping and essential records): 

‘Essential records are the documents and data (and relevant metadata), in any format, associated with a clinical trial that facilitate the ongoing management of the trial and collectively allow the evaluation of the methods used, the factors affecting a trial and the actions taken during the trial conduct to determine the reliability of the trial results produced and the verification that the trial was conducted in accordance with GCP and applicable regulatory requirements…’.  

Appendix C of ICH GCP E6 (R3) gives further guidance on what records should be considered essential and therefore require retention as per Regulation 31A.  

Legal and regulatory framework 

The Medicines for Human Use (Clinical Trials) Regulations 2004 (as amended) requires sponsors to maintain a Trial Master File (TMF) containing essential records that enable evaluation of trial conduct and data quality. 

Regulation 31A of the clinical trials regulations mandates retention of essential documents and participant medical files for at least 25 years from the conclusion of the trial, or longer if required for marketing authorisation purposes. 

ICH E6(R3) Good Clinical Practice requires essential records to be complete, legible, and readily available for inspection throughout the retention period. 

Retention periods 

Retention of the essential records within the TMF (including the investigator site file) and the medical records of trial participants is a legal requirement as described in Regulation 31A.

The sponsor and the investigator, and any delegated service providers, must ensure that the documents contained, or that have been contained, in the TMF, as well as the medical files of trial participants are retained for at least 25 years beginning the day after the conclusion of the trial.  

If at the date of the expiry of the 25 years, the data generated by the trial is being used to support an application for a UK marketing authorisation, the sponsor shall ensure the essential records are retained for at least the period of 2 years beginning with the day after the grant of that UK marketing authorisation. 

For authorised products, the Human Medicines Regulations, via Regulation 50(5) reference to Annex 1 of the 2001/20/EC Directive includes requirements for the retention of all other documentation pertaining to the trial by the sponsor or other owner of the data for as long as the product is authorised with the final clinical study report being retained for 5 years after the product is no longer authorised. 

There are also additional considerations for:

• participant medical records which may be required to be retained for longer than 25 years if required by other legislation or by institutional policy such as NHS Records Management Code of Practice 

• advanced therapy investigational medicinal products where traceability records are required to be retained for 30 years after product expiry or longer if required by the clinical trial authorisation

Sponsors, investigators and delegated service providers must ensure that essential records are readily available, complete, and legible at all times during the retention period for inspection by the MHRA or other competent authorities. 

Named person responsible for archiving 

Regulation 31A (9) requires that the sponsor appoints a named individual within the organisation to be responsible for archiving the documents which are, or have been, contained in the TMF, and that access to these documents must be restricted to those appointed individuals and auditors or inspectors.  

It should be noted that the named individual should have oversight of the retention of those records which are electronic in nature as well as paper-based records. 

Archiving and data integrity 

The MHRA GXP data integrity guidance states the MHRA’s position on requirements for archiving of essential records to ensure data integrity and the minimum expectation to achieve compliance. Examples of such include: 

• security and access: access to archived records must be restricted to named individuals appointed by the sponsor 

• format and authenticity: original records or certified true copies must be retained. Scanning processes must be validated to ensure authenticity and completeness 

• electronic records: systems must maintain audit trails, metadata, and ensure long-term readability. Migration to new formats must be validated and documented 

• environmental controls: storage conditions must protect against deterioration, fire, flood, pests, and unauthorised access

It is expected that investigators and sponsors (and any individual or organisation that the sponsor delegates trial related activities to) have due regard to the expectations contained in the MHRA GXP data integrity guidance. 

Transfer of ownership 

Where there is a change of ownership of essential records connected with the clinical trial, for example, transfer of a marketing authorisation to another organisation, then the sponsor must record the transfer, and the new owner must be responsible for ongoing data retention and archiving. 

Where a sponsor closes (for example goes into administration) then the record retention requirements remain and transfer to the Chief Investigator as described in Regulation 31A (7). The TMF must remain accessible and complete to ensure compliance with regulatory requirements and to safeguard participant data. 

Destruction of records 

Records must not be destroyed before the end of the retention period. 

Where records have been damaged or destroyed accidentally then an assessment should be conducted to determine the extent and impact of the lost or damaged records. If the assessment is found to impact on the ability to present the records for inspection then a serious breach notification should be considered. 

Implications for transitional provisions (old rules and new rules) 

Schedule 14 3(2) states regulation 31A (7) of the old rules, rather than regulation 31A (7) of the new rules, applies in respect of old rules clinical trials.  

For the avoidance of doubt: 

• ‘old rules clinical trials’ are those where clinical trial applications were submitted before the relevant day. With ‘the relevant day’ meaning the day on which this regulation came into force (28 April 2026). These trials must comply with retention and archiving obligations stipulated in the old clinical trial regulation 31A (7, & 7A)

• the sponsor and the chief investigator shall ensure that the documents contained, or which have been contained, in the trial master file are retained for at least 5 years after the conclusion of the trial and that during that period are (a) readily available to the licensing authority on request; and (b) complete and legible 

• if, at the date of the expiry of the 5 years, the data generated by the trial is being used to support an application for a UK marketing authorisation, the sponsor shall ensure the essential records are retained for at least the period of 2 years beginning with the day after the granting of that UK marketing authorisation

However, the requirement for retention of medical records in ‘old rules clinical trials” must follow the new regulation 31A (8):

• the sponsor and chief investigator shall ensure that the medical files of trial participants are retained for at least the period of 25 years beginning with the day after conclusion of the trial, or such period as is required by any other enactment, if longer

• ‘new rules clinical trials’ meaning a clinical trial which is not an old rules clinical trial (namely that the clinical trial application was submitted on or after the relevant day, 28 April 2026) must comply with updated regulation for retention and archiving obligations stipulated the new clinical trial regulation 31A (7, 7A and 8) as outlined above in Section 4 

• for all trials, regardless of whether they are ‘old rules clinical trials’ or ‘new rules clinical trials’, that relate to an authorised product then all other documentation pertaining to the trial must be retained for as long as the product is authorised with the final clinical study report being retained for 5 years after the product is no longer authorised