Oxford–AstraZeneca COVID-19 vaccine
The Oxford–AstraZeneca COVID-19 vaccine , codenamed AZD1222 , [5] and sold under the brand name Covishield and Vaxzevria among others, [19] [20] is a viral vector vaccine for COVID-19 developed by Oxford University and AstraZeneca given by intramuscular injection , using as a vector the modified chimpanzee adenovirus ChAdOx1 . [21] [22] [23] [24] An analysis published on 19 February 2021 showed an efficacy of 76.0% at preventing symptomatic COVID-19 beginning at 22 days following the first dose, increasing to 81.3% when the second dose is given 12 weeks or more after the first. [25] Oxford–AstraZeneca COVID-19 vaccine Box containing 100 COVID-19 Vaccine AstraZeneca doses Vaccine description Target SARS-CoV-2 Vaccine type Viral vector Clinical data Trade names Vaxzevria, [1] Covishield [2] [3] Other names AZD1222, [4] [5] ChAdOx1 nCoV-19, [6] ChAdOx1-S, [7...