multicenter, randomized, controlled trials
All patients are ≥18 years, healthy or have medically stable chronic diseases and are at increased risk for SARS-CoV-2 virus exposure.
United Kingdom: 12 390 patients dosed with a half or full dose of AZD 1222 or MenACWY meningococcal vaccine comparator.
Brazil: 10 3000 participants randomized to receive 2 full doses of AZD 1222 or comparator as first dose, placebo as second.
Booster dose in both trials is administered one month after the original.