Which COVID Vaccine Is Made by AstraZeneca, and Is It Approved in the U.S.? On 3/12/21 at 5:27 AM EST Multiple COVID vaccines are now rolling out across the U.S., but one brand has been absent despite approvals by other countries. That vaccine, by British-Swedish pharmaceutical company AstraZeneca and the U.K.'s University of Oxford, is now known simply as COVID-19 Vaccine AstraZeneca, however was formally called AZD1222. Before that, it was titled ChAdOx1 nCov-19. Like vaccines from Pfizer-BioNTech and Moderna, it stimulates the immune system and causes the body to produce protection against the disease. The vaccine works by pushing the genetic code of the virus that causes COVID into body cells. A spike protein is then produced. After that, an immune response kickstarts, giving the body a way to recognise—and fight—a future coronavirus infection.