AstraZeneca’s COVID-19 Vaccine More Effective When Given 12 Weeks Apart, Analysis Finds
An analysis by researchers at the University of Oxford has found that the AstraZeneca (AZ)/Oxford coronavirus vaccine appears more effective when its two doses are administered three months apart, results in line with those unveiled by AZ earlier this month.
In a pooled analysis of the vaccine’s UK, Brazil and South Africa trials, the researchers found that a two-dose regimen of the vaccine demonstrated 55.1 percent efficacy when given six weeks apart, according to their peer-reviewed report in The Lancet. The vaccine was more effective, however, when administered 12 weeks apart, where it showed 81.3 percent efficacy.
“A three-month dose interval might have advantages over a program with a short-dose interval for rollout of a pandemic vaccine to protect the largest number of individuals in the population as early as possible when supplies are scarce, while also improving protection after receiving a second dose,” the Oxford researchers said.
The results of the peer-reviewed analysis are consistent with AZ’s primary analysis from the same trials unveiled early this month, in which the company reported that a dosing interval of 12 weeks or more demonstrated 82 percent efficacy (DID, Feb. 4).
The new findings support UK and World Health Organization (WHO) recommendations on the timing of vaccine doses. The UK currently recommends giving second doses four to 12 weeks after the initial shot, while the WHO recommends administering the second dose eight to 12 weeks apart.
The company has not yet filed for Emergency Use Authorization with the FDA, as its phase 3 U.S. trial is ongoing.
Read the full analysis here: bit.ly/3px4v4N. — James Miessler