Here is what you should know about world’s ‘leading’ COVID-19 vaccine candidate

World Health Organization (WHO) chief scientist last month described AstraZeneca’s COVID-19 vaccine candidate as the world’s leading candidate and most advanced in terms of development.

Soumya Swaminathan had said that Moderna’s COVID-19 vaccine candidate was also “not far behind” Astrazeneca’s, among more than 200 candidates, 15 of which have entered clinical trials.

Here is what you should know about AstraZeneca’s AZD1222

It uses a replication-deficient chimpanzee viral vector based on a weakened version of a common cold (adenovirus) virus that causes infections in chimpanzees and contains the genetic material of SARS-CoV-2 spike protein.

After vaccination, the surface spike protein is produced, priming the immune system to attack COVID-19 if it later infects the body.

The recombinant adenovirus vector (ChAdOx1) was chosen to generate a strong immune response from a single dose and it is not replicating, so cannot cause an ongoing infection in the vaccinated individual.

Last month, AstraZeneca reached an agreement with Europe’s Inclusive Vaccines Alliance (IVA), spearheaded by Germany, France, Italy and the Netherlands, to supply up to 400 million doses of the University of Oxford’s potential COVID-19 vaccine, currently in clinical development.

Earlier, the company reached a $750m agreement with CEPI and Gavi to support the manufacturing, procurement and distribution of 300 million doses of the potential vaccine, with delivery starting by the end of the year