The Oxford University team that uses a recombinant viral vector vaccine that uses a chimpanzee adenovirus vaccine vector (ChAdOx1) that carries the genetic sequence of novel coronavirus spike protein will begin Phase-1 trial today (April 23).

The Oxford University will today (April 23) begin a Phase-1 clinical trial of its vaccine called ChAdOx1 nCoV-19 against the novel coronavirus (SARS-CoV-2). “The vaccine from the Oxford project will be trialled in people from this Thursday,” Health Secretary Matt Hancock said during a daily press conference yesterday. 

The vaccine will be tested on 500 healthy volunteers aged 15 and 55 in the Thames Valley region and will focus on safety and tolerability. It will also assess the effectiveness of the vaccine to stimulate an immune response against the virus. 

According to The New York Times, the researchers plan to carry out a mid-stage efficacy trials of the vaccine. “They then plan to expand the trial group to older age groups later, and hope to run a final phase trial with around 5,000 volunteers in the late summer, “ the report said. 

The vaccine is a recombinant viral vector vaccine that uses a chimpanzee adenovirus vaccine vector (ChAdOx1) that carries the genetic sequence of the coronavirus surface ‘spike’ protein inside the ChAdOx1 construct. Vaccination with the spike protein is expected to stimulate an immune response thus protecting against virus infection.

The vaccine will comprise only one dose and does not use a replicating virus, so it cannot cause an infection in the vaccinated individual. Adenoviral vectors are a very well-studied vaccine type, having been used safely in many people, including HIV vaccine trials. 

The Oxford University project — led by Prof Sarah Gilbert, Prof Andrew Pollard, Prof Teresa Lambe, Dr Sandy Douglas and Prof Adrian Hill — started working on a vaccine in early January shortly after China shared the genetic sequence of the virus. The team had earlier developed a vaccine for Middle East Respiratory Syndrome (MERS), which has shown promise in early clinical trials. The MERS vaccine could generate an immune response for at least a year after vaccination.

British scientists are already manufacturing a million doses of the vaccine and these will be available by September, even before trials prove whether the vaccine is safe and effective.

Published in The Hindu on April 23, 2020