Evaluate Azvudine in Preventing SARS-Cov-2 Infection in Household Contacts of Covid-19 in China

A Phase II Randomized, Double-Blind, Placebo-Controlled Trial to Evaluate the Efficacy and Safety of Azvudine in Preventing SARS-Cov-2 Infection in Household Contacts of Individuals Infected with SARS-CoV-2 in China

Inclusion Criteria:1、18-65 years old at the signing of informed consent. 2、Household contacts of individual with symptomatic COVID-19. Symptomatic COVID-19 cases (index case) to be identified as those symptomatic and recently tested (rapid antigen test or RT-PCR) positive for SARS-CoV-2 and must fulfill the following criteria 1) collection of the first positive SARS-CoV-2 test sample less than 24 hours before randomization, 2) have at least one symptom attributable to COVID-19.3、RT-PCR test negative (with nasopharyngeal [NP] swab samples) OR rapid antigen test negative at the time of screening and without any suspicious COVID-19 symptoms within 2 weeks before randomization.4、Subject expects to be living in the same household with the symptomatic COVID-19 cases during the whole study period.Exclusion Criteria:Subject with a history of SARS-CoV-2 vaccinations within 1 months before randomization.Subject with a history of SARS-CoV-2 infection within 6 months before randomization.With any serious infection requiring systemic anti-infective therapy within 14 days before randomization.Allergic to the investigational agent or any components of the formulation. Pregnant or breast-feeding women.Women of childbearing potential who are unwilling to practice highly effective contraception during the study, and for at least 6 months after the study; Sexually active men who are unwilling to use medically acceptable birth control during the study period.Have other conditions not suitable for inclusion as judged by the investigator.