Coronavirus vaccine update: What are 'human challenge' trials?
New Delhi, Oct 21: In hunt for a viable COVID-19 vaccine, the UK government has given approval for 'human challenge' trial so that an effective vaccine can be produced at the earliest.
Human challenge studies provide a faster way to test vaccines because you don't have to wait for people to be exposed to an illness naturally.
The concept of human challenge trial is not new, but it remains controversial as participants in such a trial are injected with the virus.
What is 'human challenge' trial?
Around 90 volunteers will be recruited to be exposed to small amounts of the novel coronavirus in a controlled setting for the first stage of "human challenge" trials to try and speed up the hunt for a viable COVID-19 vaccine.
It comes with a 33.6 million pound investment for experts from the National Health Service (NHS), academia and the private sector to join forces to make the UK among the first countries in the world to explore and establish human challenge trials to accelerate the development of a COVID-19 vaccine.
If approved by regulators and the ethics committee, the studies would start in January next year with results expected by May 2021.
How does Human challenge trial work?
In human challenge studies, a vaccine candidate that has proven to be safe in initial trials is given to a small number of carefully selected healthy adult volunteers, who are then exposed to the virus in a safe and controlled environment.
Medics and scientists then closely monitor the effect on volunteers 24 hours per day to see exactly how the vaccine works and to identify any side effects.
Using controlled doses of virus, the aim of the research team will initially be to discover the smallest amount of virus it takes to cause COVID-19 infection in small groups of healthy young people, aged between 18 and 30, who are at the lowest risk of harm.
Up to 90 volunteers, who will be compensated for the time they spend in the study, could be involved at this stage, the UK government said without revealing the payment involved for the volunteers.
What studies say about Human challenge trial
"Human challenge studies can increase our understanding of COVID-19 in unique ways and accelerate development of the many potential new COVID-19 treatments and vaccines," said Dr Chris Chiu, from the Department of Infectious Disease at Imperial College London and lead researcher on the human challenge study.
"Our number one priority is the safety of the volunteers. My team has been safely running human challenge studies with other respiratory viruses for over 10 years. No study is completely risk free, but the Human Challenge Programme partners will be working hard to ensure we make the risks as low as we possibly can," he said.
The studies are conducted under strict conditions - these include a controlled entrance to the facility, careful decontamination of waste and a dedicated laboratory for carrying out tests, all of which help to ensure the study is delivered safely and securely. All the air leaving the unit is also cleaned so there is no risk to anyone outside the unit.
"This research will improve understanding of the virus, the biology of the disease, the signs that a person is protected from infection or developing the disease, the vaccine candidates, and will help in making decisions about research, that it is carried out safely and based on up-to-date evidence," said Kate Bingham, Chair of the government's Vaccine Taskforce.
UK plan to be first to run human challenge Covid trials
While the UK hopes to be the first to begin these human challenge studies, the proposed research must first be considered by regulators including the Medicines and Healthcare products Regulatory Agency (MHRA) and the NHS Health Research Authority through research ethics committees before the research starts.
England's Deputy Chief Medical Officer Professor Jonathan Van-Tam said a safe, fully approved, and meticulously controlled human challenge model for COVID-19 may help in the search for safe and effective vaccines.
"First, for the many vaccines still in the mid-stages of development, human challenge studies may help pick out the most promising ones to take forward into larger Phase 3 trials," said Van-Tam.
"Second, for vaccines which are in the late stages of development and already proven to be safe and effective through Phase 3 studies, human challenge studies could help us further understand if the vaccines prevent transmission as well as preventing illness," he said.
The first stage of the Human Challenge Programme will be delivered by a partnership between Imperial College London, the Royal Free Hospital's specialist and secure research unit in London and clinical company hVIVO, which is considered a pioneer in viral human challenge models.
"Our subsidiary hVIVO is the world leader in the testing of vaccines and antivirals using human challenge studies and our contract with the UK government to develop a COVID-19 human challenge study model will safely accelerate the discovery of effective vaccines and antivirals against COVID-19," said Cathal Friel, Executive Chairman of Open Orphan, hVIVO's parent company.
The study will take place in "world-class clinical facilities" at the Royal Free Hospital, specifically designed to contain the virus. Highly trained medics and scientists will be on hand to carefully examine how the virus behaves in the body and to ensure volunteer safety. Volunteers will be monitored for up to a year after participating in the study to ensure their long-term well-being.