AstraZeneca COVID-19 vaccine shows up to 90% effectiveness in early data

Preliminary results on a third coronavirus vaccine, this one from AstraZeneca and the University of Oxford, show promise. This is no less exciting for being the third, behind Pfizer and Moderna: The coronavirus pandemic is a challenge too big to be quickly ended by one effective vaccine. We need every possible tool against it, and AstraZeneca's has some key benefits.

The vaccine showed average 70% effectiveness across trials of two different dosages. Interestingly, the less effective regimen, at 62%, used two full doses a month apart, while the more effective option, at 90%, was a half dose followed by a full dose a month later. If that result holds, it could mean more people being vaccinated. Importantly, it's much cheaper than either the Pfizer or Moderna vaccines, and can be stored at normal refrigerator temperatures, while the others can only be stored at refrigerator temperature for a limited time.

"We're not thinking about vaccinations working in terms of one person at a time. We have to think about vaccinating communities, populations, reducing transmission within those populations, so that we really get on top of this pandemic,″ said Sarah Gilbert, one of the Oxford researchers. "And that's what it now looks like we're going to have the ability to contribute to in a really big way."

In Great Britain, the vaccine trial included weekly COVID-19 testing for participants, which Pfizer and Moderna did not do, instead testing people who developed possible COVID-19 symptoms. That means AstraZeneca is more likely to have uncovered asymptomatic cases. None of the people who received the new vaccine and did develop COVID-19 were hospitalized.

This is excellent, excellent news. Now we just need to try to keep from spreading the virus until these vaccines can get through to authorization and distribution.