The first results of a recent animal trial of coronavirus vaccine from Oxford University have shown promising results.The report showed that the monkeys given a single shot of the vaccine developed antibodies against the virus within 14 days. Protective antibodies were developed by all monkeys within 28 days before being exposed to higher doses, it added. The preliminary findings also indicated that the "ChAdOx1 nCoV-19" vaccine has been effective in preventing damage to the lungs.
"The most important finding to me is the combination of considerable efficacy in terms of viral load and subsequent pneumonia, but no evidence of immune-enhanced disease, which has been a concern for vaccines in general, for example with vaccines against respiratory syncytial virus (RSV), and for SARS vaccines," Prof Stephen Evans, Professor of Pharmacoepidemiology, London School of Hygiene and Tropical Medicine, said.
The potential for antibody-dependent enhancement of the disease is considered as one of the key challenges with vaccines against the coronavirus species, the experts said. It has been a primary reason for the lack of a vaccine against the 2003 SARS CoV strain, they added.
"It is helpful to see that monkeys vaccinated with this SARS CoV2 vaccine did not have any evidence of enhanced lung pathology and that, despite some evidence of upper respiratory tract infection by SARS COV2 after high viral load virus challenge, monkeys given the vaccine did not have any evidence of pneumonia," Dr Penny Ward, Visiting Professor in Pharmaceutical Medicine at King's College London said.
Globally, more than 3 lakh people have died and nearly 45 lakh have tested positive for the deadly virus since its emergence in Wuhan last December.