By Holly Giles | Deputy Editor
The UK was the first country in the world to licence a vaccine for COVID-19 and this week it has made another milestone by gaining approval for the first human challenge trials for the virus. They have previously been used for a number of diseases, including malaria, typhoid, cholera and flu, but this is the first time COVID-19 will join the list.
Human challenge trials involve healthy volunteers being deliberately infected with coronavirus in order to answer key questions about the virus such as: what is the smallest dose needed to start an infection? How does the immune system respond to infection? How can you tell which people will develop symptoms?
Chief investigator, Dr Chris Chiu, said: “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”.
Business Secretary Kwasi Kwartend, added:
“Whilst there has been very positive progress in vaccine development, we want to find the best and most effective vaccines for use over the longer term. These human challenge studies will take place here in the UK and will help accelerate scientists’ knowledge of how coronavirus affects people and could eventually further the rapid development of vaccines”.
With thousands of people being vaccinated every day it may seem unnecessary to perform these tests but as Clive Dix from the Vaccines Taskforce, explains these insights are still crucial to fighting the virus: “We have secured a number of safe and effective vaccines for the UK, but it is essential that we continue to develop new vaccines and treatments for COVID-19. We expect these studies to offer unique insights into how the virus works and help us understand which promising vaccines offer the best change of preventing the infection.”
The trials will include 90 healthy volunteers aged 18-30 who will be screened for the virus before starting the program to check they haven’t been exposed to COVID-19 previously. They will then have a small dose of the virus squirted up their nose before being monitored for 14 days of isolation in a hospital and undergoing a number of tests. The follow-up will then continue for a year so the researchers can monitor long-lasting symptoms.
The main aims of the study are to find out how the virus grows in the hose and analysing the initial stages of infection before symptoms develop. It is hoped this increased understanding about carriers of the infection could help stop the transmission of the virus.
Whilst this study will use the main UK variant which has been present in the country since the first lockdown, it has been suggested future trials could look at other variants. Other future studies could include giving participants a vaccine and then exposing them to new variants to check which vaccinations are the most effective, but this is yet to be approved.
This possibly was explained by Professor Robert Read from Southampton Biomedical Research Centre:
“A human challenge allows you to vaccinate volunteers and then infect them in a controlled way with the virus to compare perhaps new vaccines with first-generation vaccines to provide information to the regulatory authorities so that they can understand the potential of novel vaccines head to head with the established vaccines that already exist”.
It is not known when these additional studies will receive approval but means this first human challenge study is unlikely to be a stand-alone, and more likely to be the first of many.
Whilst this is a big undertaking for volunteers and a big decision to make, it is worth noting they will be given £4500 during the year for their participation in the study.
The Human Challenge study 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.
With the COVID-19 pandemic entering its eleventh month and still seeing over 12,000 new cases a day in the UK, increased understanding of the virus is paramount for returning to “normal” life in the near future. This human challenge study will add to an increasing field of knowledge about the virus and help researchers find more ways to tackle it effectively.
It will be some time before the results of the human challenge study are seen, but with it expected to recruit participants this month, the COVID-19 human challenge study is well underway.