Vaccine experts have questions about the COVID-19 vaccine data from AstraZeneca.
Vaccine experts — including those who served on advisory committees for the Food and Drug Administration in the United States (US FDA) and the US Centers for Disease Control and Prevention (CDC) — have questions about COVID-19 vaccine data that was released by AstraZeneca.
This, as AstraZeneca announced in a press release on Monday that its COVID-19 vaccine was on average 70% effective. However, AstraZeneca didn’t state the COVID-19 vaccine data that led them to that conclusion.
Dr. Paul Offit, a member of the Food and Drug Administration’s Vaccines and Related Biological Products Advisory Committee, said that it was hard to know the significance of AstraZeneca’s findings.
AstraZeneca presented in its press release an analysis of 23,000 participants in its Phase 3 clinical trial.
Several participants received the COVID-19 vaccine, while others received a different kind of vaccine or placebo injections.
AstraZeneca said in its press release that a total of 131 study participants developed COVID-19, but it didn’t say how many of those people had received the vaccine and how many didn’t.
In addition, AstraZeneca was running the vaccine trials in collaboration with the University of Oxford in the UK.
Also, the experts had questions about AstraZeneca COVID-19 vaccine’s safety and clinical trial.
2,741 participants in the first regimen received a half-dose of COVID-19 vaccine and then a full dose of COVID-19 vaccine at least a month later, while 8,895 participants in the second regimen received a full dose of COVID-19 vaccine and followed by another full dose of COVID-19 vaccine at least a month later.
The group that received the half-dose initially was 90 percent protected against coronavirus disease, and the group that received two full doses of COVID-19 vaccine was only 62 percent protected.
Dr. Adrian Hill, one of the lead Oxford researchers, said that it would take “probably weeks and months” to understand the reason why the lower dose yielded much better results.
According to the AstraZeneca press release, the clinical trials for the COVID-19 vaccine were still underway in some countries and would eventually include under 60,000 study participants by the end of 2020.
Yale School of Medicine’s vaccine specialist Dr. Saad Omer noted that the group with the 90% efficacy rate was “relatively small” and those results might not hold up when more people were given the said regimen.
He also noted a lack of clarity about some aspects of AstraZeneca’s vaccine data, saying “I hate to criticize fellow academics, or anyone for that matter, but releasing information like this is like asking us to try and read the tea leaves.”