Publication Bueno S, Clin Infect Dis, 2021
Dates: 2020-11-27 to 2021-02-10
Funding: Public/non profit (Ministry of Health of the Chilean Government; Confederation of Production and Commerce, Chile; Consortium of Universities for Vaccines and Therapies against COVID-19, Chile; Millennium Institute on Immunology and Immunotherapy.)
Conflict of interest: Yes
Multicenter / Chile |
Follow-up duration (months): 1.4
|• CoronoVac (3 mcg) (n=270)
• Placebo (aluminum hydroxide adjuvant) (n=164)
2 IM doses of 3 mcg CoronaVac, 14 days apart
2 IM doses of adjuvant, 14 days apart
|Characteristics of participants|
Type of participants: People in close contact with COVID-19 patients, Healthcare workers.
Pregnant women: 0
Immunocompromized patients: 0
Mean age: NR
Age range: NR
|Description of participants|
Adult healthcare workers with no history of confirmed symptomatic SARS-CoV-2 infection who were in contact with possible or confirmed cases of COVID-19 in 8 sites in Chile.
|In the register|
Frequency of solicited and unsolicited adverse events that occur during the period of one week after each dose of the vaccine in two vaccination schedules: 0,14 and 0,28 days stratified by age group (18-59 years, and 60 or more years). [ Time Frame: During the first 7 days after each dose of vaccine ] Incidence of symptomatic cases of virologically confirmed COVID-19 two weeks after the second dose of each vaccination schedule. [ Time Frame: Two weeks after second dose up to one year after first dose ]
|In the report|
The primary aim was to evaluate the frequency of solicited and unsolicited AEs that occur during 7 days after each dose, stratified by age group (aged 18-59 and ≥60).
Yes. In English
|Risk of bias
The overall risk of bias reported in the table corresponds to the highest risk of bias for the outcomes assessed for the systematic review
In addition to the published article, the trial registry, protocol and statistical plan were used in data extraction and assessment of risk of bias. The article reports an interim analysis including 434 participants. As this is an interim analysis, the pre-stated sample size was not achieved. Substantial changes were made to the original trial registry regarding participant characteristics (changed to no longer being restricted to health care workers), the intervention comparison (vaccine versus placebo control replaced with vaccine delivered days 0 and 28 versus days 0 and 14), blinding (changed from blinded to open label) and outcomes (removal of two secondary outcomes). However, the interim analysis reported in the pre-print adheres to the original trial registry. In the article, authors report randomization with 1:1 ratio for intervention/control groups however, the number of participants per group on the flow chart and result tables, doesn't correspond to this ratio.
This trial was updated on October 11th 2021, after the publication of the study report.