UK Launches World’s First COVID-19 Human Challenge Study

UK Launches World’s First COVID-19 Human Challenge Study

What You Should Know:

– This week, the United Kingdom (UK) will be the first country in the world to run a COVID-19 human challenge study, following approval from the UK’s clinical trials ethics body.

– First Covid-19 human challenge study will begin within a month, after receiving ethics approval in the same week the UK hits target of offering first dose to 15 million people.

– Researchers call on healthy young people to volunteer for the study, which will play a key role in developing effective COVID-19 vaccines and treatments.


Backed by a £33.6 ($46.5 USD) million UK government investment, the first-of-its-kind study for this virus will involve establishing the smallest amount of virus needed to cause infection, which will give doctors greater understanding of COVID-19 and help support the pandemic response by aiding vaccine and treatment development.

UK COVID Challenge: How It Works

The UK COVID Challenge is being delivered by a partnership between the government’s Vaccines Taskforce, Imperial College London, the Royal Free London NHS Foundation Trust and the industry-leading clinical company hVIVO, which has pioneered viral human challenge models.

Slated to start in the new few weeks, 90 carefully selected, healthy adult volunteers being exposed to the virus in a safe and controlled environment. The UK COVID Challenge study will initially use the version of the virus that has been circulating in the UK since March 2020 and has been shown to be of low risk in young healthy adults. Medics and scientists will closely monitor the effect of the virus on volunteers and will be on hand to look after them 24 hours a day.

The virus being used in the characterization study has been produced by a team at Great Ormond Street Hospital for Children NHS Foundation Trust in London, in collaboration with hVIVO with support from virologists at Imperial College London.

Researchers are encouraging people aged between 18 and 30 years old, who are at the lowest risk of complications resulting from coronavirus, to volunteer for this vital study. Volunteers will be compensated for the time they spend in the study. Once this initial study has taken place, vaccine candidates, which have proven to be safe in clinical trials, could be given to small numbers of volunteers who are then exposed to the COVID-19 virus, helping to identify the most effective vaccines and accelerate their development.

This initial study will also help doctors understand how the immune system reacts to coronavirus and identify factors that influence how the virus is transmitted, including how a person who is infected with COVID-19 virus transmits infectious virus particles into the environment.

“We are asking for volunteers aged between 18 and 30 to join this research endeavour and help us to understand how the virus infects people and how it passes so successfully between us. Our eventual aim is to establish which vaccines and treatments work best in beating this disease, but we need volunteers to support us in this work,” said Chief Investigator Dr Chris Chiu, from Imperial College London.

Safety Measures

The researchers are also working very closely with the Royal Free Hospital and the North Central London (NCL) Adult Critical Care Network to ensure the study will not impact on the NHS’ ability to care for patients during the pandemic. The study will not begin without their go-ahead.

Understanding the Human Challenge Model Approach vs. Standard Vaccine Clinical Trials

The Human Challenge Model is a study during which healthy volunteers are deliberately exposed to a virus, known as the “challenge virus”. This approach is different to standard vaccine clinical trials where volunteers are exposed to viruses naturally. The key benefit is the Human Challenge Model can provide a more efficient and faster way to develop vaccines as fewer volunteers are required.

Over many decades, human challenge studies have been performed safely and have played important roles in accelerating the development of treatments for diseases including malaria, typhoid, cholera, norovirus and flu. The trials have also helped researchers establish which possible vaccine is most likely to succeed in phase 3 clinical trials that would follow, usually involving thousands of volunteers. To date, hVIVO has completed 50 research projects which have included over 3,000 volunteers, using viruses such as Influenza, Respiratory Syncytial Virus (RSV) and Human Rhinovirus (HRV). The COVID-19 Human Model approach will help development of COVID-19 specific vaccines and treatments.

“This study is a key enabling study to establish the COVID-19 challenge model and determine the lowest possible dose of virus required. Data from this study will immediately facilitate the challenge model to be used for vaccine efficacy testing as well as to answer a wide range of fundamental scientific questions that are not feasible with traditional field trials, such as exactly what type of immunological response is required to confer protection from re-infection,” said Chief Scientific Officer at hVIVO, Dr Andrew Catchpole.