Oxford University on Wednesday said the AstraZeneca coronavirus vaccine is not only able to stave off disease but can reduce transmission — the first evidence of its kind.
University researchers said they regularly tested participants in a U.K. trial and found a 67% reduction in positive readings compared to the placebo group.
Scientists figured that COVID-19 vaccines slowed the spread of the virus, beyond stiff-arming disease, but were waiting on better data. The new data underscore the need for widespread vaccination to control the pandemic, especially among asymptomatic people who don’t realize they are infected and transmit the virus in the community.
Also, Oxford researchers found the AstraZeneca vaccine was 76% effective after a single dose and that protection increased when the second shot was given 12 weeks later, validating a decision by the U.K. and other countries to maximize their supply of first-round shots and give the second one later than planned.
In fact, the pre-print study found the longer interval increased protection, at 82% after three months, compared to only 55% if given after six weeks.
“This primary analysis reconfirms that our vaccine prevents severe disease and keeps people out of hospital. In addition, extending the dosing interval not only boosts the vaccine’s efficacy, but also enables more people to be vaccinated upfront,” said Sir Mene Pangalos, executive vice president for biopharmaceuticals. “Together with the new findings on reduced transmission, we believe this vaccine will have a real impact on the pandemic.”
The AstraZeneca vaccine hasn’t been approved for use in the U.S.
The Food and Drug Administration is waiting on the results of a 30,000-person U.S. trial. The data should be available later this month, clearing the way for regulatory review and approval.
U.S. officials will likely debate whether to give the AstraZeneca second shot a few months later, instead of four weeks as planned.
They’re under pressure to stretch the dosing schedule for approved vaccines from Pfizer/BioNTech and Moderna, although those vaccines use a messenger-RNA platform that is different from AstraZeneca’s adenovirus version.
Some experts say it would be foolish for regulators to riff on what was proven in human trials.
For now, Dr. Anthony Fauci is applauding the introduction of new weapons in the fight. He says time is of the essence because failure to control the virus is allowing it to mutate into potentially more dangerous versions.
Johnson & Johnson could see approval this month of a one-dose vaccine that was 72% effective in the U.S., potentially speeding the campaign as regulators take stock of the latest data from Britain.
“I certainly have every reason to believe the Brits, but I’d like to see the data myself. If that’s true, it’s good news,” Dr. Fauci told NBC’s “Today Show” on Wednesday. “Yet again, another vaccine candidate in the mix. We heard yesterday about the Russian Sputnik candidate which had over 90% efficacy.”
“Johnson & Johnson, from last week, also had some good results,” Dr. Fauci said. “So as we are going on getting into February, we’re going to have multiple candidates in the mix, which is good news.”
