Controlled Human Infection Studies

Project Overview

Controlled human infection (CHI) studies aim to find preliminary efficacy results of vaccine or therapeutic candidates by deliberately inoculating a small number of healthy volunteers with the pathogen of interest. Global guidance and standardization are warranted for quality and comparability among CHI studies.

Ethical concerns often raised for CHI studies range from direct risks and benefits to participants, risks to third parties, informed consent, participation remuneration, and community engagement. Important mechanisms to ensure ethical conduct of CHI studies include rigorous design, risk minimization, stakeholder engagement, fair participant selection, robust informed consent, and proportionate payment, among others. Global guidance and standardization are warranted for quality and comparability among CHI studies.

Project Aims

Research into the ethics of CHI studies is one of the key areas under IEPI’s Translational Science pillar. The overall aim of this project is to support international health organizations and researchers in identifying and addressing ethical considerations relevant to CHI studies. Most recently, IEPI joined the WHO’s working group responsible for providing stakeholders of COVID-19 CHI studies with research and ethics guidance.

In addition to COVID-19 related topics, IEPI has conducted research on the landscape of general ethics issues related to CHIMs and gaps in existing ethical frameworks. By identifying these gaps, IEPI aims to construct an enhanced framework that will provide ethical guidance on governance, data sharing, and community engagement projects. Other research topics being pursued by IEPI range from CHIMs in the pediatric population, universal influenza vaccine development, capacity building in low- and middle-income countries, and data sharing, to assessing the risk and social value of CHI studies.

Early during the COVID-19 pandemic, CHIMs were suggested as an option to accelerate the vaccine development process. However, this approach is controversial among scientists. Proponents argue that CHI studies can rapidly identify potentially safe vaccine candidates to move to later trial phases by testing on a very small group of healthy volunteers under strictly controlled environmental conditions. At the time when there was no vaccine for COVID-19, the possibility of accelerating vaccine development was highly anticipated. On the other hand, opponents of the CHI approach argue that deliberately inoculating volunteers with SARS-CoV-2 is too risky given the life-threatening potential of developing the disease without access to effective treatments. Risk of community infection, issues with informed consent and voluntary withdrawal, and appropriate participant compensation are also at the forefront of the debate.

Project Partners

WHO – A United Nations agency specialized in public and global health. The agency promotes universal healthcare, publishes global guidelines to help citizens attain the highest level of health, and responds to public health emergencies.

Wellcome Trust – Funds discovery research into life, health and wellbeing, and supports research to find solutions to three categories of health challenges: mental health, infectious disease,and climate.

International Alliance for Biological Standardization (IABS) – An international, independent, non-profit alliance of scientists with the objective to improve the quality and regulation of biological products.