Jenner Institute at Oxford looks to recruit healthy volunteers for controversial ‘challenge trial’
The team behind the Oxford Covid-19 vaccine hope to begin tests on volunteers who will be intentionally exposed to the virus in a “challenge trial”, a move seen as controversial since there is no proven cure for the illness.
Although challenge trials, in which healthy volunteers are given a pathogen, are routine in vaccine development, taking the approach for Covid-19, where there is no failsafe treatment if a volunteer becomes severely ill, has been questioned.
In human challenge trials volunteers are intentionally exposed in a controlled laboratory setting, meaning the trial can be completed in weeks and requires far fewer people.
The Oxford vaccine has already been tested in a phase-one trial involving about 1,000 British volunteers, with full details due to be published in the Lancet on Monday. Tens of thousands of people are also being recruited in the UK, Brazil, South Africa and the US for a further stage of testing, known as phase three.
A senior team member has said that preparations have begun for the human challenge trial to run in parallel with phase three, which would require only tens of volunteers to test the efficacy of the vaccine.
Prof Adrian Hill, director of Oxford University’s Jenner Institute, said that Oxford scientists were working in the laboratory on the technical side of preparation for such a trial and that the team hoped to recruit volunteers within months.
“We’re hoping to be doing challenge trials by the end of the year,” he said. “This might be in parallel or might be after the phase three trial is completed. They’re not competing options, they’re complementary.”