Covid-19 Living Data

Trial NCT04383574
Publication Li M, medRxiv, 2021
Dates: 2020-07-12 to 2020-07-15
Funding: Public/non profit (National Key Research and Development Program, Beijing Science and Technology Program, and National Science Fund for Distinguished Young Scholars. L.W. and Y.W. were the employees of Sinovac Biotech Ltd., L.W. was an employee of Sinovac Life Sciences Co., Ltd.)
Conflict of interest: Yes

Methods
	RCT
	Location : Single center / China Follow-up duration (months): 10.46
	1.5μg Coronavac (n=100) 3μg Coronavac (n=100) 6μg Coronavac (n=100) Placebo (n=50)
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 1.5 mcg, 28 days apart followed by 1 booster dose of 1.5 mcg 8 months later 2 IM doses of 3.0 mcg, 28 days apart followed by 1 booster dose of 3.0 mcg 8 months later 2 IM doses of 6.0 mcg, 28 days apart followed by 1 booster dose of 6.0 mcg 8 months later
	Control 2 IM doses of aluminum hydroxide diluent placebo, 28 days apart followed by 1 placebo booster 8 months later
Participants
	Randomized 350 participants
	Characteristics of participants Type of participants: Older adults N=350 149 males Children: 0 Pregnant women: 0 Immunocompromized patients: 0 Mean age: Age range: NR
	Description of participants Healthy adults aged ≥60 years with no known history of COVID-19 or recent exposure in a single center 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: 28 days after the second dose vaccination ]
	In the report Geometric mean titre (GMT) and seropositivity rate of neutralizing antibodies to live SARS-CoV-2 on day 180 after two-dose primary vaccination, and on days 7, 14, and 28 after the third dose. Any vaccine-related adverse event (adverse reaction) within 28 days after administration of the third dose of vaccine or placebo in phase 2 trial, and serious adverse events from immunization till 6 Healthy adults aged ≥60 years with no known history of COVID-19 or recent exposure in a single center in China months after two doses in both phase 1&2 trials.
Documents available	Protocol Yes. In English Statistical plan Yes Data-sharing stated: Yes, After the trial is completed. Data accessibility: All the data referred to in the manuscript will be provided with reasonable request after the trial is completed. Yuliang Zhao: Yuliang_zh1@163.com; Hongjie Yu: yhj@fudan.edu.cn; Weidong Yin: 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 pre-print article, the registry, protocol and statistical analysis plan for the original phase 1-2 trial were used in data extraction and assessment of risk of bias. The article reports safety and immunogenicity outcomes in an extension of the phase 2 trial in which blinding was maintained and participants were given a third booster dose or placebo at 8 months after the original second dose. Consequently none of the booster outcomes were included in the protocol or registry.