The pharmaceutical company AstraZeneca has announced that a vaccine co-invented by the University of Oxford and its spin-out company, Vaccitech, has proven to be up to 90% effective against the SARS-CoV-2 virus which causes COVID-19.

The vaccine, called AZD1222, proved to be 90% effective against the virus when a half-dose was given, followed by a full dose a month later.  It was 62% effective when the virus was given in two whole doses, given a month apart.  The study group was around 23,000 people in Brazil and the United Kingdom.

The companies plan to seek regulatory approval from health agencies around the world, including Emergency Use Authorization from the U.S. Food and Drug Administration.  AstraZeneca will also seek an Emergency Use Listing from the World Health Organization for an accelerated pathway to vaccine availability in low-income countries. In parallel, the full analysis of the interim results is being submitted for publication in a peer-reviewed journal.

An independent Data Safety Monitoring Board determined that the analysis met its primary endpoint showing protection from COVID-19 occurring 14 days or more after receiving two doses of the vaccine. No serious safety events related to the vaccine have been confirmed.  AZD1222 was well tolerated with the half dose or the full dose.

The company said it will have as many as 200 million doses by the end of 2020.  The company says 700 million doses could be ready globally as soon as the end of the first quarter of 2021.  And the cost for this vaccine is said to be less than the vaccines also likely coming soon from Pfizer and Moderna.  The vaccine can be stored, transported and handled at normal refrigerated conditions for at least six months and administered within existing healthcare settings.  It will not require the super cold dry ice conditions as will the Pfizer and Moderna vaccines.  Both the Pfizer and Moderna vaccines are proving to be around 95% effective against the SARS-CoV-2 virus.

AZD1222 uses a replication-deficient chimpanzee viral vector based on a weakened version of a common cold virus (adenovirus) (photo attached)  that causes infections in chimpanzees and contains the genetic material of the SARS-CoV-2 virus spike protein. After vaccination, the surface spike protein is produced, priming the immune system to attack the SARS-CoV-2 virus if it later infects the body.

Photo is the adenovirus provided by AstraZeneca.