Medicines and Healthcare products Regulatory Agency (MHRA) review

The Medicines and Healthcare Products Regulatory Agency are a national oversight body who oversee the safe and appropriate use of medicinal products and medical devices in the UK. This includes responsiblity for overseeing research conducted in accordance with the Medicines for Human Use (Clinical Trials) Regulations and the Medical Device Regulations.

Clinical Trial of an Investigational Medicinal Product (CTIMPs)

A CTIMP is any study that will generate new information about the safety and/or efficacy of one or more medicinal products. A medicinal product is a substance presented in a pharmacological form with the intention of affecting a clinical or physiological outcome. A product that a CTIMP generates information about is referred to as an Investigational Medicinal Product (IMP).

This includes studies of licenced medicinal products, if they will be used in any way other than as described in their licence or if new information will be generated. 

This includes studies where the medicinal product is not the subject of the study but new information will or may be generated - due to its use as a control, for example.

This does not include studies of foods or food supplements.

The Clinical Trial Regs. refer to this type of study as a 'Clinical Trial'. It is important to note though, that there are other commonly used definitions of Clinical Trial: the World Health Organisation (WHO) use it to refer to any interventional healthcare study; some funders, such as the National Institutes of Health (NIH), use a similar definition to WHO, some insurance policies define a Clinical Trial as anything overseen by the MHRA (thereby including CTIMPs and CIMDs). In short, when discussing 'Clinical Trials' it's always best to check what definition others are using.


Applications to the MHRA are generated via IRAS. For a CTIMP, selecting option 1 on filter question 2 will open follow-up filter questions and will add Section B1 to the main form. The details required by the MHRA will be recorded in this form and then downloaded. Once this has been reviewed by Research Governance, we will submit it to the MHRA - usually in parallel with the REC/HRA application.

Safety reporting

The Clinical Trial regs require that strict Safety Reporting be observed for CTIMPs - regardless of the perceived risk of the study or the licensing status of the product.


The MHRA are required to inspect organisations conducting CTIMPs. This will either take the form of a routine inspection, usually of a Sponsor, during which they will inspect a number of studies from the Sponsor's portfolio; or a triggered inspection, where a concern has been raised about the conduct of an organisation, or a specific study.


CTIMPs are generally the most time-consuming studies to set up. It is difficult to generalise, as the nature and complexity of CTIMPs varies widely, but it is best to allow for between twelve and eighteen months, from funding confirmation to opening the first recruiting site.

For a CIMD, you must notify the MHRA of your intentions at least 60 days prior to your intended start-date. In addition, determining whether a study is a CIMD or not is often the most complicated and time-consuming part of the process. Unless you have definitive confirmation, one way or the other, you should allow roughly 90 days for this decision to be reached.

Clinical Investigation of a Medical Device (CIMDs)

A Medical Device is defined, in the Medical Devices Regulations, as:

an instrument, apparatus, appliance, material or other article, whether used alone or in combination, together with any software necessary for its proper application, which:

  1. is intended by the manufacturer to be used for human beings for the purpose of:
    1. diagnosis, prevention, monitoring, treatment or alleviation of disease,
    2. diagnosis, monitoring, treatment, alleviation of or compensation for an injury or handicap,
    3. investigation, replacement or modification of the anatomy or of a physiological process, or
    4. control of conception; and:
  2. does not achieve its principal intended action in or on the human body by pharmacological, immunological or metabolic means, even if it is assisted in its function by such means.

A CIMD is a study intended to generate generate information to support the licencing (via CE mark / UKCA mark) or the marketing of a Medical Device.


Often one of the most difficult elements of setting up a study that involved a Medical Device is determining whether or not it is a CIMD. If there is any uncertainty at all in this area contact Research Governance [LINK mailto:] as early as possible to discuss. We will generally refer the question to the MHRA devices specialists, in order to do this we will need a copy of the study protocol. This can be an early draft of the protocol, so long as the objectives and methodology are clear.

If Research Governance and the MHRA determine that your study is a CIMD, it will need to be submitted as such via IRAS. Please refer to the MHRA's detailed guidance on preparing a submission (PDF, 212kB).

Safety reporting

As with other types of research, the appropriate level of Safety Reporting [LINK: internal] will depend on the specific study design - however, as a minimum, events that meet the Serious criteria and are possibly, probably or definitely related to a device under investigation must be reported to the Sponsor and, if unexpected, to the REC and MHRA. These events are refered to as Serious Adverse Device Effects (SADEs).