NCT04952727

Study on Sequential Immunization of Inactivated COVID-19 Vaccine and Recombinant COVID-19 Vaccine (Ad5 Vector) in Elderly Adults

Safety and Immunogenicity of Sequential Immunization of Inactivated COVID-19 Vaccine and Recombinant COVID-19 Vaccine (Ad5 Vector) inChinese Healthy Adults Aged 60 and Above: a Randomized, Observer-blind,Parallel-controlled Clinical Trial

• Status: Completed
• Phase: Phase 4
• Study type: Interventional
• Enrollment: 300 (actual)
• Sponsor: Jiangsu Province Centers for Disease Control and Prevention · Network
• Sex: All
• Age: 60 Years
• Healthy volunteers: Accepted

Summary

This is a randomized, observer-blind, parallel-controlled study, for evaluation of safety and immunogenicity of sequential immunization of a recombinant COVID-19 vaccine (adenovirus type 5 vector) in Chinese healthy adults aged 60 and above after the priming vaccination of inactivated vaccine. 300 healthy subjects aged 60 and above will be recruited in this study. Of them, 200 subjects who have been vaccinated with two dose of inactive SARS-CoV-2 vaccine will be recruited and randomized at a 1:1 ratio to receive a booster dose of inactivated SARS-CoV-2 vaccine or recombinant SARS-CoV-2 Ad5 vectored vaccine at 3\~6 months later. Other 100 subjects who have been vaccinated with one dose of inactivated SARS-CoV-2 vaccine will be recruited and randomized at a 1:1 ratio to receive a booster dose of inactivated SARS-CoV-2 vaccine or recombinant SARS-CoV-2 Ad5 vectored vaccine at 1\~3 months later. The occurrence of adverse events within 28 days and serious adverse events within 6 months after vaccination will be observed. In addition, blood samples will be collected on day 0 before the boosting with ad5 vectored vaccine and on day 14, 28 and month 6 after the boosting. Serum antibody levels, cellular immune responses and the subgroups or germlines of the specific B cells will be analyzed. Each subject will remain in this study for approximately 6 months.

Conditions

• COVID-19

Interventions

Type	Name	Description
BIOLOGICAL	Recombinant SARS-CoV-2 Ad5 vectored vaccine	This vaccine contains 5×10\^10 virus particles of recombinant replication defective human type 5 adenovirus expressing SARS-CoV-2 S protein, which is produced by CanSino Biologics Inc. It is a liquid dosage form, 0.5 ml / bottle.
BIOLOGICAL	Inactive SARS-CoV-2 vaccine (Vero cell)	This vaccine contains 600 SU of SARS-CoV-2 antigen, which is produced by Sinovac Research \& Development Co., Ltd. 0.5 ml / bottle.

Timeline

• Start date: 2021-08-26
• Primary completion: 2021-11-26
• Completion: 2022-05-15
• First posted: 2021-07-07
• Last updated: 2022-08-16

Locations

1 site across 1 country: China