Very rare thrombosis with thrombocytopenia after second AZD1222 dose: a global safety database analysis

Summary: A post-hoc analysis was conducted on the efficacy of the ChAdOx1 nCoV-19 vaccine against the B.1.1.7 variant of SARS-CoV-2 in the UK. The vaccine showed reduced neutralisation activity against the B.1.1.7 variant in vitro, but still demonstrated efficacy against the B.1.1.7 variant of the virus.

Summary: After vaccination with ChAdOx1 nCov-19, rare immune thrombotic thrombocytopenia can occur due to platelet-activating antibodies against PF4, resulting in various thrombotic events. Most patients in this case series were women, with fatal outcomes such as cerebral venous thrombosis and intracranial hemorrhage. Additional studies are needed to further investigate and understand this phenomenon.