Human Challenge Trial – Need, Benefits and Challenges

As Companies race to bring out a vaccine against the Covid-19, Experts are divided on whether the challenge model for vaccine trials should be put to use in the current pandemic. Many people have volunteered to take part in the Human Challenge Trials (HCTs) which involves intentionally infecting volunteers with the novel Coronavirus, in order to speed up the vaccination development. Initiatives like 1DaySooner have seen massive registration of people in many countries who had signed up for such trials voluntarily. Clinical trials are essential to test the safety and efficacy of new treatments in any population. Advocates of  HCT believe that such trials could save valuable time in developing vaccines like a Covid-19 vaccine, as researchers would not have to wait for participants to contract the infection under real-world conditions. A paper in The Journal of Infectious Diseases has proposed replacing Phase 3 with human challenge trials which may subtract many months from the licensure process, making efficacious vaccines available more quickly. However, human challenge studies are ethically sensitive and raise several controversial and unresolved issues in research ethics.