Study design and participants
Prometheus
SARS-COV-2 INFECTION, RECRUITMENT
Prometheus is a multicentre, randomised, double-blind, placebo-controlled, clinical trial being conducted in six centres in the Russian Federation. The study seeks to evaluate the immunogenicity, efficacy, reactogenicity and safety of a single dose of the Ad5-nCoV COVID-19 vaccine compared with placebo in adults up to 6 months after vaccination. Competitive recruitment of the planned sample size of 500 eligible participants in six centres was completed in November 2020 and follow-up observations were completed on 05-May-2021. A planned interim analysis of data collected in 200 participants up to 28 days after a single injection of Ad5-nCoV or placebo was completed on 21-December-2020. Herein, we present the results of final analysis of data collected in 496 participants up to 6 months after a single injection of Ad5-nCoV or placebo.Participation was sought through online recruitment advertising and patient databases of the trial sites. All participants underwent detailed screening 1–10 days before vaccination with Ad5-nCoV or placebo (Day 0). Screening included the detection of SARS-CoV-2 RNA using real-time polymerase chain reaction (PCR) via a swab, and SARS-CoV-2 immunoglobulin M (IgM) and immunoglobulin G (IgG) antibody testing to ensure negative results, as well as testing for human immunodeficiency virus (HIV), syphilis, hepatitis B and hepatitis C viruses via blood serum. A detailed medical history for each participant was taken and records included if the participant experienced any COVID-19 symptoms and if the participant was in close contact with people suspected or proven to have SARS-CoV-2 infection. Participants underwent physical examination (including a neurological examination, vital signs, and body temperature), haematological, biochemical and coagulation testing, urine analysis, electrocardiogram, and when applicable, pregnancy testing as pregnancy (and breastfeeding) was an exclusion criterion.Men and women aged 18–85 years with a body mass index (BMI) between 18.5 and 30.0 kg/m