Trial NCT04383574
Publication Wu Z, Lancet Infect Dis, 2021
Dates: 22/05/2020 to 15/06/2020
Funding: Public/non profit (The National Key Research and Development Program; the Beijing Science and Technology Program)
Conflict of interest: Yes

Methods
RCT
Location : Single center / China
Follow-up duration (months): 1.84
•1.5 mcg CoronaVac (n=100)
•3 mcg CoronaVac (n=124)
•6 mcg CoronaVac (n=124)
•Placebo (n =74)
Inclusion criteria
  • Healthy adults aged 60 years or older.
Exclusion criteria
  • High-risk epidemiological history within 14 days before enrolment (eg, travel to or residence in Wuhan and surrounding areas or other communities with reports of COVID-19 cases, or contact with someone infected with SARS-CoV-2)
  • history of severe acute respiratory syndrome or SARS-CoV-2 infection
  • axillary temperature of more than 37·0°C
  • a history of allergy to any vaccine component.
Interventions
Intervention
2 IM doses of 1.5mcg per dose, on days 0, 28
2 IM doses of 3mcg per dose, on days 0, 28
2 IM doses of 6mcg per dose, on days 0, 28
Control
2 IM doses on days 0, 28
Participants
Randomized
422 participants
Characteristics of participants
Type of participants: Older adults
N=422
206 males
Children: 0
Pregnant women: 0
Immunocompromized patients: 0
Mean age: NR
Age range: NR
Description of participants
Healthy adults aged 60 years and older with no history of SARS-CoV-2 infection in a single centre in China
Primary outcome
In the register
Safety index-incidence of adverse reactions [ Time Frame: Day 0-28 after each dose vaccination ]; Immunogenicity index-seroconversion rates of neutralizing antibody [ Time Frame: The 30th day after the second dose vaccination ]
In the report
Vaccine-related adverse event (adverse reaction) within 28 days after the administration of each dose of vaccine or placebo; Seroconversion rate of neutralising antibodies to live SARS-CoV-2 at day 28 after the second dose
Documents
available

Protocol

Yes. In English

Statistical plan

Yes

Data-sharing stated: Yes, The data will be available immediately after publication and finalisation of the completed clinical study report for at least 1 year. Supporting clinical documents including the study protocol and statistical analysis plan and the informed consent form will be available immediately following the publication of the current Article for at least 1 year.
Data accessibility: Corresponding authors: Dr Yuliang Zhao, Hebei Provincial Center for Disease Control and Prevention, Shijiazhuang, Hebei 050021, China; yuliang_zh1@163.com or Dr Weidong Yin, Sinovac Biotech, Beijing 100085, China; yinwd@sinovac.com
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 the published article, the protocol, statistical analysis plan, and study registry were used in data extraction and risk of bias assessment. The units for vaccine doses were different in the trial registration and protocol compared to the published article. The safety data of the phase 1 and phase 2 trial were combined for analysis because the same batches of vaccine and placebo and the same safety observation method were used. The immunogenicity data for phase 1 and phase 2 trials were reported separate, data for the second phase was extracted. For the outcome Adverse events the authors reported "adverse reactions" defined as "adverse events related to vaccination". Primary outcomes were reported as pre-specified in the registry. Both Phase 1 and 2 trials achieved their pre-stated sample size. This is an early interim analysis of a Phase 1 and a Phase 2 trial in which follow up is continuing.