Oxford Vaccine Effort Towards COVID-19

Oxford University has joined the global effort to fight COVID-19 (also referred to as SARS-Cov2) and is recruiting healthy volunteers to test a new vaccine. This comes after both the USA and China announced that they were starting clinical trials of COVID-19 vaccines. The team from the University’s Jenner Institute is working in collaboration with the Oxford Vaccine Group to conduct the trial which has been approved by UK regulators.

The team, led by Prof. Sarah Gilbert, Prof. Andrew Pollard, Prof. Teresa Lambe, Dr. Sandy Douglas and Prof. Adrian Hill, started designing the vaccine on the 10th of January as soon as the first genome sequence of COVID-19 was made publicly available. The vaccine candidate put forward for the trial uses a chimpanzee adenovirus vector (ChAdOx1) previously developed by the Jenner Institute. It was chosen as the most suitable vaccine technology as only one dose is required to generate a strong immune response and the adenovirus vector is defective so cannot cause an infection in the vaccinated individual. So far, the ChAdOx1 vector technology has been successfully used in vaccines targeting over 10 different diseases.

Coronaviruses (including COVID-19. SARS and MERS) have a club-shaped protein on their surfaces called spike protein. Previous studies of coronavirus vaccines suggested that the spike protein is a good vaccine target. The genetic sequence of the COVID-19 surface spike protein is introduced inside the ChAdOx1 vector. Once the ChAdOx1 vector enters a cell, the host machinery transcribes and translates the genetic sequence and the COVID-19 spike protein is expressed. The spike protein then serves as a training tool for B cells, leading to the production of antibodies against the spike protein. Antibodies work as tailored weapons targeting a specific pathogen, in this case, COVID-19. A vaccinated individual is expected to develop an effective immunological arsenal against COVID-19 which will be instrumental to fight and prevent the infection or, at least, reduce its severity.

Due to the urgent need for means to fight the COVID-19 pandemic, the production of the vaccine is already being scaled up to produce enough stock for large clinical trials and potentially future deployment. This will ensure that as soon as the vaccine is proven safe and effective, it can be available for the people that need it the most, including frontline healthcare workers, the elderly and those with underlying health conditions.

Writen by Kate Dicker, WT IITM DPhil student

References:

  1. Clinical Trials Arena. Covid-19: China to launch clinical trials for coronavirus vaccine, (2020).
  2. Clinical Trials Arena. First US clinical trial of Covid-19 vaccine candidate begins, (2020).
  3. University of Oxford. Oxford COVID-19 vaccine programme opens for clinical trial recruitment, (2020).
  4. University of Oxford. About the COVID-19 vaccine trials ,(2020).