Oxford's Coronavirus Vaccine Is 70% Effective, Early Data Shows. It's The Third Vaccine To Clear A Crucial Hurdle.

A COVID-19 vaccine developed by the University of Oxford and AstraZeneca has shown "positive high-level results" in early data from clinical trials, researchers announced Monday. It is the third vaccine to clear that crucial hurdle, alongside ones made by Pfizer and Moderna.

The vaccine has been 70% effective on average so far, researchers said. The early data came with a potentially promising surprise: The vaccine was 90% effective for volunteers who were given a half-dose of the vaccine followed by a full dose — a much higher success rate than those who were given two full doses, which was 62% effective.