Trial NCT04651790
Publication Abarca K, medRxiv, 2022
Dates: 2020-11-29 to 2021-04-09
Funding: Mixed (Ministry of Health, Government of Chile; The Confederation of Production and Commerce (CPC); SINOVAC contributed to this study with the investigational vaccine and placebo, and experimental reagents. )
Conflict of interest: no COI
Methods | |
RCT | |
Location :
Multicenter / Chile Follow-up duration (months): 6.0 | |
CoronaVac D0/D14 (n= 1090) CoronaVac D0/D28 (n= 1212) | |
Inclusion criteria |
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Exclusion criteria |
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Interventions | |
Intervention
2 IM doses of 3 mcg, 14 days apart |
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Control
2 IM doses of 3 mcg, 28 days apart | |
Participants | |
Randomized 2302 participants | |
Characteristics of participants Type of participants: Healthy Adults N=2302 1090 males Children: 0 Pregnant women: 0 Immunocompromized patients: 0 Mean age: Age range: 18+ | |
Description of participants Healthy adults including health care workers with no history of confirmed symptomatic SARS CoV-2 infection at eight centres in Chile | |
Primary outcome | |
In the register 1. 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 ]; 2. 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 1. Frequency of AE occurring on the first 7 days after each dose of the vaccine in each vaccination schedule; 2. Confirmed SARS-CoV-2 infection of two vaccination schedules, starting two weeks after the second dose. | |
Documents available |
Protocol NR Statistical plan * Data-sharing stated:
Yes, After publication |
Risk of bias Overall The overall risk of bias reported in the table corresponds to the highest risk of bias for the outcomes assessed for the systematic review |
Some concerns |
General comment | In addition to two version of the pre-print article, the prospective study registry and supplementary materials were used in data extraction and risk of bias assessment. The protocol and statistical analysis plan were not available. The primary outcomes reported reflect those in the registry, which was adapted from a concurrent vaccine versus placebo trial to reflect a comparison of two schedules. The article presented 6 month preliminary analyses for a study with ongoing follow-up. Some secondary outcomes (Specific antibodies GMT, cellular immune response) were listed in the registry, but not reported in the paper. The target sample size (n=2300) specified in the registry was achieved (n=2302). |