LONDON (AP) – AstraZeneca’s COVID-19 vaccine provided strong protection against disease and eliminated hospitalizations and deaths from the disease, including in older adults, in the final stages of US testing, the company announced Monday.
AstraZeneca said its experts have not identified any safety concerns related to the vaccine, including not finding an increased risk of rare blood clots identified in Europe.The question now is whether the findings will help restore public confidence in the vaccine around the world as the company seeks approval in the United States.
In a statement, AstraZeneca said the COVID-19 vaccine was 79% effective in preventing symptomatic COVID-19 and was 100% effective in stopping serious illness and hospitalization, although it has not yet published full data, so it is unclear whether there were sufficiently serious cases. to make that finding significant. Researchers said the vaccine worked for adults of all ages, including older people – something experts wanted better data on.
AstraZeneca’s interim results are based on 141 COVID-19 cases, but officials declined to tell reporters at a news conference on Monday how many volunteers were in the study who received the vaccine and how many of those who received fake injections.
“These findings confirm the results previously observed,” said Ann Falsey, of the University of Rochester School of Medicine, who helped lead the trial. “It’s exciting to see similar efficacy results for the first time in people over 65 years old.”
AstraZeneca will seek approval for use of the vaccine in the United States from the Food and Drug Administration in the first half of April, Ruud Dobber, an executive vice president of the company, told reporters Monday. An FDA advisory committee will publicly debate the evidence behind the shots before the agency decides whether to allow emergency use. Dobber said that if the FDA approves the vaccine, the company will deliver 30 million doses immediately – and another 20 within the first month.
The AstraZeneca Injection, which has been approved in more than 70 countries, is a pillar of a UN-backed project known as COVAX that aims to bring COVID-19 vaccines to poorer countries, and it has also become an important tool in European countries’ efforts to stimulate their slow roll-out of vaccines. But confidence in the shot has received repeated hits because of concerns about how data from some previous studies were reported, confusion about its effectiveness in older adults, and a recent fear of clotting.
Stephen Evans, of the London School of Hygiene & Tropical Medicine, said the new data could help address concerns about the vaccine.
“The benefits of these results will be especially for the rest of the world, where confidence in the AZ (AstraZeneca) vaccine has been shattered, in large part by political and media comments,” he said.
The study involved more than 30,000 volunteers, two-thirds of whom received the vaccine, with the rest receiving sham injections. Two doses were given to humans four weeks apart.
Dr. Paul Hunter, a professor of medicine at the University of East Anglia, said the results were reassuring, but more details were needed to support AstraZeneca’s claim that the vaccine was fully effective in preventing serious illness and hospitalization.
“It would be good to know how many severe cases occurred in the control group and thus what the confidence intervals are for this 100% figure,” said Hunter, who was not associated with the study. “But this should bolster confidence that the vaccine is doing what it needs most.”
Scientists had hoped the American study would clear up some of the confusion about how well the shots really work, especially in older people. Previous research suggested the vaccine was effective in younger populations, but there was no solid data proving its effectiveness in people over 65, often those most vulnerable to COVID-19.
Britain first approved the vaccine based on partial results from tests in the UK, Brazil and South Africa that suggested the injections were about 70% effective. But those results were clouded by a manufacturing flaw that caused some participants to receive only half a dose in their first shot – a flaw that the researchers didn’t immediately recognize.
Then more questions arose about how well the vaccine protected older adults and how long to wait for the second dose. Some European countries, including Germany, France, and Belgium, initially withheld the admission of older adults and only reversed their decisions after new data suggested it provided protection for seniors.
AstraZeneca’s vaccine development was also slow in the US. Last fall, the FDA suspended the company’s study for an unusual six weeks as frustrated regulators sought information on some of the neurological complaints reported in Britain; in the end, there was no evidence that the vaccine was to blame.
Last week, more than a dozen countries, mostly in Europe, temporarily discontinued their use of the AstraZeneca injection after reports that it was linked to rare blood clots – even as international health authorities insisted that the benefits of the vaccine outweighed its risks. On Thursday, the European Medicines Agency concluded after investigation that the vaccine did not increase the overall risk of blood clots, but could not rule out that it was linked to two very rare types of blood clots. It recommended adding a warning about these cases to the package insert for the vaccine.
It’s not unheard of for such rare problems to crop up when vaccines are rolled out, as trials typically look at tens of thousands of people, and some problems aren’t noticed until the shot is used on millions of people.
France, Germany, Italy and other countries then resume their use of the shot on Friday, with senior politicians rolling up their sleeves to show the vaccine was safe.
AstraZeneca said it would continue to analyze the US data before submitting it to the FDA in the coming weeks. It said the data would also be published in a peer-reviewed journal soon.
The AstraZeneca shot is what scientists call a “viral vector” vaccine. The recordings were made with a harmless virus, a cold virus that normally infects chimpanzees. It acts like a Trojan horse to deliver the genetic material of the coronavirus spike protein to the body, which in turn produces a harmless protein. That stimulates the immune system to fight when the real virus comes along.
Two other companies, Johnson & Johnson and CanSino Biologics of China, make COVID-19 vaccines with the same technology but different cold viruses.
Neergaard reported from Washington.
Follow AP’s pandemic coverage at https://apnews.com/hub/coronavirus-pandemic, https://apnews.com/hub/coronavirus-vaccine and https://apnews.com/UnderstandingtheOutbreak