The AstraZeneca COVID-19 vaccine, following reassurances late last week from top European health officials about its safety, is receiving a new round of endorsement about its efficacy.
AstraZeneca trial results involving 32,449 adult participants in all age groups, most of them in the United States, showed 79% efficacy against symptomatic COVID-19 and 100% effectiveness against severe illness, according to the Washington Post.
Ruud Dobber, president of AstraZeneca’s biopharmaceuticals business unit, announced that the company plans to apply for emergency use authorization from the U.S. Food and Drug Administration in April, according to CNN.
That would make the AstraZeneca vaccine, if approved, the fourth COVID-19 vaccine available in the U.S. and the second single-dose vaccine along with Johnson & Johnson’s vaccine that was approved in February.
“It is clear this vaccine has very good efficacy … and that this efficacy does not show a notable decline at older ages,” Stephen Evans, a professor of pharmacoepidemiology at the London School of Hygiene & Tropical Medicine, said in a statement to the Science Media Centre in the U.K. He noted in his statement that anything above 60% was considered good.
The 79% figure is also a marked improvement over what was reported in a December 2020 study. As Stat News reported then, that study found “two standard doses of the vaccine were 62% effective in preventing symptomatic COVID-19 disease in some trials. But when efficacy data from the trials were combined—including trials in which volunteers received a low dose followed by a standard dose of vaccine—the vaccine was deemed to be 70% efficacious.”
“The data look good. The numbers don’t lie,” said Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, after being briefed on the data.
“The one thing that one can say for sure, that this is good for the world, because it’s a cheap vaccine,” he added. “It’s got good results. They will likely be able to produce enough for a lot of different countries.”
Concerns about potential links to its use and blood clots led to a number of European nations halting its use by mid-March. After the March 18 “safe and effective” ruling from the European Medicines Agency, a number of those countries have resumed its use.
AstraZeneca issued a press release March 22 indicating that an independent board identified no safety concerns related to the shot. It was the latest attempt from both the company and public health officials to reassure the public about its safety.
As CNBC noted, the board “conducted a specific review of blood clots as well as cerebral venous sinus thrombosis, an extremely rare blood clot in the brain, with the help of an independent neurologist.”
Furthermore, the study “found no increased risk of thrombosis or events characterized by thrombosis among the 21,583 participants receiving at least one dose of the vaccine. The specific search for CVST found no events in this trial.”
AstraZeneca is touting the latest efficacy numbers. Mene Pangalos, a company official, noted, “These results add to the growing body of evidence that shows this vaccine is well tolerated and highly effective against all severities of COVID-19 and across all age groups. We are confident this vaccine can play an important role in protecting millions of people worldwide against this lethal virus.”