LONDON — The University of Oxford and AstraZeneca’s coronavirus vaccine was 90 percent effective in preventing COVID-19 In studies of more than 22,000 people in the UK and Brazil, AstraZeneca said in a November 23 press release. Like Russia’s Sputnik…

The Oxford and AstraZeneca Covid-19 vaccine candidate’s late-stage trial results are “really exciting” but more work needs to be done, said Professor Andrew Pollard on Monday. Phase III trial results found it was 90% effective if administered at a half…