Chennai: While hailing ‘good news’ from two Covid-19 vaccine candidates in early human trials, Michael Ryan, the head of emergencies at the World Health Organisation, has however warned that there was a long way to go.
Speaking to journalists, Ryan said, “We now need to move into larger-scale real-world trials. But it is good to see more data and more products moving into this very important phase of vaccine discovery.”
He made these remarks after scientists at Oxford University, in a paper published in the medical journal The Lancet, said their experimental vaccine had been shown to trigger a protective immune response in hundreds of people who got the shot.
Also, in the journal, Chinese researchers from CanSino Biologics published a study on their experimental vaccine, which uses a similar technique as the Oxford team, that also reported an immune response.
In The Lancet, Oxford University scientists said their vaccine candidate, prepared in partnership with the pharma giant AstraZeneca, appeared safe in the early trial phases, inducing a strong immune response within the body. Doses of the vaccine were given to 1,077 healthy adults aged between 18 and 55 in five UK hospitals in April and May as part of the phase I clinical trial and results.
The results show they induced strong antibody and T-cell responses for up to 56 days after they were given. T-cells are immune responses by the body against the foreign virus, and are crucial for maintaining protection against the virus for longer periods of time.
Andrew Pollard, chief investigator of the Oxford vaccine trial, said, “In addition, the strongest immune responses were produced in 10 participants who received two doses of the vaccine, indicating that this might be a good strategy for vaccination.”
On the other hand, a vaccine candidate under development by China’s CanSino Biologics Inc and the country’s military research unit, showed similar safe immune response in most of the 508 healthy volunteers.
Both CanSino and Oxford-AstraZeneca are adenoviral vector vaccines; that means they are prepared from a weakened, non-replicating version of a common cold virus that carries the coronavirus spike proteins into the human body, helping the immune system identify and build antibodies against the virus.
In India…
At least seven Indian pharma companies are working to develop a vaccine against coronavirus as they join global efforts to find a preventive to check the spread of the pandemic. Bharat Biotech, Serum Institute, Zydus Cadila, Panacea Biotec, Indian Immunologicals, Mynvax and Biological E are among the firms working on Covid-19 vaccines in India.