Researchers from the Oxford University have published in ‘Preprints of The Lancet’ an analysis of additional data from the ongoing trials of its COVID-19 vaccine, developed jointly with pharmaceutical company AstraZeneca. In addition, the authors give the first clues about the potential of the vaccine to reduce the transmission of the coronavirus: have observed a 67% reduction in infections after the first dose in their UK trial volunteers.
These data are important because, to date, a lot of data have been published on the effectiveness of vaccines in preventing disease, but it is not yet known whether they prevent those vaccinated from becoming infected and are asymptomatic contagious.
On the other hand, in their work they reveal that the efficacy of the vaccine is greater at longer booster intervals, and that a single dose of the vaccine is 76 percent effective from 22 to 90 days after vaccination.
In this pre-print, which is currently under review by ‘The Lancet’, they report on an analysis of additional data to include trial information up to December 7, 2020, which includes a further 201 cases of primary symptomatic COVID-19 (332 cases out of 131 previously notified). So, point out that the effect of dosing interval on efficacy is pronounced, with a vaccine efficacy increasing from 54.9% with an interval of less than six weeks to 82.4% when 12 or more weeks are separated.
They also detail that a single standard dose of the vaccine has a 76% effective in protecting against COVID-19 symptomatic during the first 90 days after vaccination, once the immune system has created this protection 22 days after vaccination, and protection shows little evidence of decline in this period.
“These new data provide important verification of the interim data that was used by more than 25 regulators to grant the emergency use authorization of the vaccine. They also support the recommendation to adopt a 12-week booster interval., as they seek the optimal approach for deployment, and it ensures that people are protected from 22 days after a single dose of the vaccine, “said the head of the trials, Professor Andrew Pollard.
In this way, the analyzes presented in this work suggest that it is the dosage interval and not the dosage level which has a great impact on the efficacy of the vaccineto. “This is in line with previous research supporting greater efficacy with longer priming intervals performed with other vaccines such as influenza, Ebola, and malaria,” says Pollard.
The researchers hope to publish data regarding the efficacy of its vaccine in the new variants of the virus “in the next days”, and they expect the results to be “very similar to those already reported by other vaccine developers.”
Eddie is an Australian news reporter with over 9 years in the industry and has published on Forbes and tech crunch.