Today’s Topic is about Human Challenge Trial
Every minute, there will be hundreds of people getting infected by COVID19. It’s a race with time to develop effective vaccines. But whether these vaccines can help depends on results of tests, especially the traditional phase three vaccine trials. However, phase three trials usually take months or even years to get enough data because during trials people who get vaccines still live normal life and researchers need to wait to see how many people get infected ultimately. And until enough people get sick, could researchers know about the effects of vaccines without data bias. So this process would require lots of volunteers and it’s really time-consuming.
To handle problems mentioned above, there’s actually another way to test effects of vaccines, namely human challenge trials. During this process, volunteers will be deliberately exposed to viruses after getting vaccines. So researchers don’t need to wait for a long time to see trial results or lots of volunteers. So it’s true that this involves risks. Usually, human challenge trials only accept young and healthy volunteers. And from data we already have, people in the ages of 20 to 29 only face less than 1 percent of possibility to be taken to hospital after getting infected. The death rate in this age group is around 5 in 1000 percent. So at least for COVID19, this human challenge trial won’t be too risky. Another benefit of human challenge trials is that these trials enable researchers to get data about early stages of infection and immune systems because they can control and know when people are exposed to viruses. Such precious data is especially helpful for studying the ways of COVID19’s transmission. Such data can hardly be obtained by traditional trials because one special aspect of COVID19 is that in early stages, many people will only be affected but won’t show any symptoms.
Now, over 39,000 people from across the world have volunteered to participate in potential COVID19 challenge trials through a nonprofit association 1Day Sooner. WHO has already cited this group as an example needed to run a challenge trial. Back in mid-October, the UK announced their intention to conduct a challenge trial at the beginning of 2021. Without doubt, results of challenge trials would shed some light on the mechanisms of COVID19 and help to stop it.
