Oxford University AstraZeneca vaccine candidate, AZD1222, against coronavirus disease (Covid-19) has shown 70% efficacy on average, according to the newly published data of phase 2/3 clinical trials held in UK and Brazil, the company announced on Monday.
In effect, the results mean that of all the people who get vaccinated, as high as 70% will not get the disease.
Also, experts had tried two different dosing regimens, of which one showed a better profile of close to 90% efficacy.
“Positive high-level results from an interim analysis of clinical trials of AZD1222 in the UK and Brazil showed the vaccine was highly effective in preventing COVID-19, the primary endpoint, and no hospitalisations or severe cases of the disease were reported in participants receiving the vaccine,” said AstraZeneca in a statement issued on Monday.
“One dosing regimen (n=2,741) showed vaccine efficacy of 90% when AZD1222 was given as a half dose, followed by a full dose at least one month apart, and another dosing regimen (n=8,895) showed 62% efficacy when given as two full doses at least one month apart. The combined analysis from both dosing regimens (n=11,636) resulted in an average efficacy of 70%,” the statement further said.
The data analysed by an independent Data Safety Monitoring Board (DSMB) determined that the analysis met its primary endpoint showing protection from Covid-19 occurring two weeks or more after receiving two doses of the vaccine.
“These findings show that we have an effective vaccine that will save many lives. Excitingly, we’ve found that one of our dosing regimens may be around 90% effective and if this dosing regime is used, more people could be vaccinated with planned vaccine supply,” said Andrew Pollard, chief investigator, Oxford vaccine trial at oxford, in a statement.
However, no serious safety events related to the vaccine have been confirmed, and the vaccine was well tolerated across both dosing regimens.
Since the results are based on an interim data analysis, the company has said it will be conducting additional analysis based on further data that gets generated over time, to refine efficacy reading and establishing the duration of protection.
AstraZeneca is now preparing regulatory submissions of the data to authorities around the world that have a framework in place for conditional or early approval.
“The Company will seek an Emergency Use Listing from the World Health Organization for an accelerated pathway to vaccine availability in low-income countries. In parallel, the full analysis of the interim results is being submitted for publication in a peer-reviewed journal,” the company statement further read.