Treatment efficacy
SARS-CoV-2 infection
ASYMPTOMATIC COVID-19, SYMPTOMATIC COVID-19, SARS-COV-2 INFECTION, SENSITIVITY
In the efficacy analysis, 1123 participants were followed for a total of 4362 days. The primary outcome laboratory-confirmed symptomatic COVID-19 developed in seven of 824 participants (incidence rate of 0.22 per 100 person-days) in the SA58-treated participants vs. 14 of 299 (incidence rate of 1.17 per 100 person-days) in the placebo group. The occurrence rate of symptomatic COVID-19 was significantly lower for SA58-treated participants vs. placebo, with a crude IRR of 0.19 (95%CI 0.08–0.48) and an estimated treatment efficacy of 80.82% (95%CI 52.41%−92.27%) (Time to first post-administration symptomatic COVID-19 (i.e. the Kaplan–Meier estimates of the cumulative risk of having COVID-19). Panel A. laboratory-confirmed symptomatic COVID-19; Panel B. SARS-CoV-2 RT-PCR positive. Abbreviation, HR, Hazard ratio; 95%CI, 95% confidence interval.Occurrence of SARS-CoV-2 RT-PCR positive and laboratory-confirmed symptomatic COVID-19 in SA58- and placebo-treated participants.Sensitivity analyses showed similar efficacy results by performing separate analyses in participants with a follow-up duration of <5 days (Supplementary Table 4), participants with a follow-up duration of ≥5 days (Supplementary Table 5), and participants who had continuous exposure to COVID-19 (Supplementary Table 6), though there was significant drop of efficacy when including participants who tested positive for SARS-CoV-2 by RT–PCR within 24 h of the first drug administration, from 80.82% to 50.30% for Symptomatic COVID-19, and from 61.83% to 32.69% for SARS-CoV-2 infection (Supplementary Table 7).