Controlled Human Infection Model studies

In a Controlled Human Infection Model (CHIM) study, a well-characterised strain of an infectious agent is given to carefully selected adult volunteers in order to better understand human diseases, how they spread, and find new ways to prevent and treat them. These studies play a vital role in helping to develop vaccines for infectious diseases. 

On 6 February 2018, the Academy of Medical Sciences, supported by the Human Infection Challenge Vaccine network, the Medical Research Council and Wellcome, held a workshop to discuss the current environment for CHIM studies in the UK and whether there was a need for additional measures to ensure appropriate oversight of this research. This built on the Academy's past report in 2005 considering this topic. 

During the workshop, which was co-Chaired by Professor Andrew Pollard FMedSci and Professor Maria Zambon FMedSci, participants raised a number of points that they felt were pertinent to the current landscape for CHIM studies:

• There continues to be significant investment in CHIM studies as part of a wider goal of tackling endemic, pandemic and emergent infectious diseases.
• There is a need to build the capacity and capabilities of low- and middle-income countries for conducting CHIM research locally.
• There is a need for an ethical framework that guides the use of CHIM studies.
• CHIM studies are not without their risks, and high quality standards of manufacturing challenge agents and conducting CHIM studies should be adhered to as far as possible.
• Increasing numbers of collaborations between sectors, both within the UK and internationally, are allowing an exchange of knowledge and expertise that can expand the use of CHIM studies and accelerate the benefits derived from them.
• Establishing an archive of challenge agents would be of great benefit to the research community.
• Registration of CHIM studies is essential to knowledge sharing and open innovation in this area of research.
• The research community should engage with regulators to ensure that regulation remains proportionate and fit for purpose in light of any developments in CHIM studies.

For the full report, including suggested next steps from the co-Chairs, please download via the link on the right. 

The regulation and oversight of CHIM studies, also known as Human Challenge Studies, Microbial Challenge Studies, and Volunteer Infection Studies, was considered by the Academy in a past report.  

The report, ‘Microbial Challenge Studies of Human Volunteers’, published in 2005, recommended the creation of a National Expert Advisory Committee to identify mechanisms to ensure the safety and welfare of human subjects involved in these studies. This Committee would have had the remit to oversee the scientific, ethical, safety, legal and societal issues of CHIM studies, to establish a central registry of studies and to provide guidance on the proper preparation and storage of CHIM materials.

While the report has helped to inform consideration of CHIM studies in the years since its publication (for example, through its checklist of ethical issues that researchers and ethics committees need to consider), regulators did not feel the creation of a new Committee was warranted and so did not implement the recommendation.