In subjects vaccinated with the approved dosage regimen (2 doses 4-12 weeks apart), 64 cases of COVID-19 were observed out of 5,258 vaccinated individuals and 154 cases out of 5,210 in the control group. Overall, the vaccine efficacy of Vaxzevria was found to be 59.5% in preventing symptomatic disease. In participants with one or more comorbidities, vaccine efficacy was very similar (58.3%).
In participants who received the second dose 12 weeks after the first, the efficacy 14 days after the second dose was 82.4% (see question "What is the expected interval between the administration of the first and second dose?").
In all participants who received at least one dose of the vaccine, no cases of hospitalisation were observed from 22 days after the first dose (0%, out of 8,032), compared to 14 cases (0.2%, out of 8,026), one of which was fatal, reported for the control group.