AstraZeneca Plc’s COVID-19 vaccine is highly effective against infection – especially among older adults, according to new data from the company’s U.S. clinical trial.
The vaccine, developed with researchers from the University of Oxford, was found to be 74 percent effective against symptomatic Covid infection.
Efficacy increased to nearly 84 percent among participants who were aged 65 and older.
This makes AstraZeneca’s vaccine less protective against infection than the Pfizer-BioNTech and Moderna vaccines at 88.8 percent and 96.3 percent, respectively, but more protective than Johnson & Johnson’s vaccine at 70 percent.
It comes as AstraZeneca plans to seek full approval of the shot with the U.S. Food and Drug Administration (FDA) this fall after numerous setbacks delayed the firm from applying for the faster emergency use authorization (EUA) in the spring.
AstraZeneca’s COVID-19 vaccine was found to be 74% effective against symptomatic infection in results from its large U.S. trial with efficacy increasing to 83.5% among participants who were aged 65 or older. Pictured: Boxes of AstraZeneca’s vaccine, June 2021
There were no cases of severe or critical COVID-19 and no deaths among vaccine recipients compared to 8 cases and 2 deaths in the placebo group (above)
AstraZeneca’s COVID-19 immunization is known as a viral vector vaccine, the same type of shot that the Johnson & Johnson vaccine is.
Viral vector vaccines combine genetic material from SARS-CoV-2 – the virus that causes Covid – with the genes of the adenovirus, which causes the common cold.
The portion taken from SARS-CoV-2 codes for the spike protein that the coronavirus uses to enter and infect cells in order to train the body to recognize the virus and induce an immune response if infected.
For the trial, which has results published in The New England Journal of Medicine on Wednesday, the team looked at 32,000 volunteers in the U.S., Chile and Peru.
Two-thirds of the volunteers received two shots of the vaccine spaced four weeks apart while the remaining one-third received two placebo shots.
ASTRAZENECA’S COVID VACCINE IS MORE PROTECTIVE AGAINST INFECTION THAN J&J – BUT LESS THAN PFIZER AND MODERNA
Efficacy of AstraZeneca against infection: 74%
Efficacy of Pfizer-BioNTech against infection: 88.8%
Efficacy of Moderna against infection: 96.3%
Efficacy of Johnson & Johnson against infection: 70%
Advertisement
There were no cases of severe or critical symptomatic COVID-19 among the participants who got the vaccine compared with eight such cases among the volunteers who got the placebo.
Additionally, there were two Covid deaths in the placebo group but none among those who received the vaccine.
Researchers determined the COVID-19 vaccine demonstrated 74 percent efficacy at preventing symptomatic disease and 83.5 percent efficacy in people aged 65 and older.
‘I was pleasantly surprised,’ Dr Anna Durbin, a vaccine researcher at Johns Hopkins University and one of the study’s investigators, told Reuters of the overall result.
‘It was also highly protective against severe disease and hospitalization.’
The most common side effects reported by the vaccine recipients were general pain, headache, injection-site pain and fatigue.
There were no cases of a rare but serious blood clotting side effect called thrombosis with thrombocytopenia that has been linked to the AstraZeneca vaccine.
The company had originally planned to file for EUA in the U.S. in spring 2021, but suffered several setbacks starting last year.
In September 2020, the U.S. arm of AstraZeneca’a vaccine trial was paused after a British participant was rushed to the hospital following a serious reaction that triggered spinal cord inflammation.
Then the company did not turn over trial safety data to the FDA for a month, further delaying the study’s resumption.
When AstraZeneca released results from an interim analysis of its clinical trial showing 79 percent efficacy in March 2021, U.S. health officials claimed the figure was based on ‘outdated information.’
AstraZeneca’s vaccine is not likely to be widely used in the U.S. with 184.3 million fully vaccinated and more than 77% of adults with at least one dose
The British drugmaker revised the figure days later to 76 percent.
In April, the firm said it was struggling to pull together the data necessary to apply for emergency use authorization in the U.S.
AstraZeneca said in late July it planned to file for full approval with the FDA rather than seek emergency use authorization.
CEO Pascal Soriot told a media briefing at the time he hoped the vaccine could still play a role in the U.S., even though the process was taking longer than expected.
The company is exploring booster doses for people who have already been vaccinated with two doses of either its own shot or mRNA-based vaccines from Pfizer/BioNTech or Moderna.
Durbin told Reuters she does not expect the vaccine to be used much in the U.S., considering most adults have already received one and children are likely to only be allowed to take the Pfizer shot.
But, she added that securing FDA approval ‘does give them gravitas.’
Source link : https://www.dailymail.co.uk/health/article-10043013/AstraZeneca-COVID-19-vaccine-shows-74-efficacy-large-U-S-trial.html
