Immunogenicity and Safety of a Third Dose of COVID-19 Vaccine(Vero Cell), Inactivated in the Elderly

An Open Clinical Trial to Evaluate Immunogenicity and Safety of a Third Dose at Different Times After Two-dose of COVID-19 Vaccine (Vero Cell), Inactivated in the Elderly Aged 60 Years and Above

This is an open phase Ⅲ clinical trial of COVID-19 vaccine (Vero cell), inactivated manufactured by Sinovac Research & Development Co., Ltd.The purpose of this study is to evaluate Immunogenicity and safety of a third dose at different times after two-dose of COVID-19 vaccine (Vero cell), Inactivated in the Elderly Aged 60 years and above.

Study Overview

• Status: Completed
• Conditions: COVID-19
• Intervention / Treatment: Biological: COVID-19 Vaccine (Vero cell), Inactivated

Detailed Description

This study is an open phase Ⅲ clinical trial. The main purpose of this study is to evaluate Immunogenicity and safety of a third dose at different times after two-dose of COVID-19 vaccine (Vero cell), Inactivated manufactured by Sinovac Research & Development Co., Ltd. in the elderly aged 60 years and above.A total of 400 subjects aged 60 years and above who had received two doses of COVID-19 vaccine(Vero Cell), inactivated manufactured by Sinovac Research & Development Co., Ltd. between 3 - 6 months ago (100 subjects for 3 months, 4 months, 5 months and 6 months,respectively) will be enrolled and receive a third dose of two-dose of COVID-19 vaccine (Vero cell), inactivated were enrolled.

• Study Type: Interventional
• Enrollment (Actual): 400
• Phase: Phase 4

Contacts and Locations

Study Locations

• China
  • Yunnan
    • Lincang, Yunnan, China, 677600
      • Yongde Center for Diseases Control and Prevention

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 60 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Subjects aged 60 years and above;
• Provide legal identification;
• Have completed two-dose of COVID-19 vaccine (Vero cell), inactivated manufactured by Sinovac Research& Development Co., Ltd. for 3~6 months（The interval between two doses was 21~35 days）；
• Be able to understand and voluntarily sign the informed consent form and be willing to complete the study according to the research plan.

Exclusion Criteria:

• History of SARS-CoV-2 infection(laboratory confirmed);
• Those who have received COVID-19 vaccine from other manufacturers other than Sinovac Research& Development Co., Ltd., or who have received booster immunization with COVID-19 vaccine after two doses of COVID-19 vaccine (Vero cell),inactivated manufactured by Sinovac Research& Development Co., Ltd.;
• History of serious adverse reactions to the vaccine or vaccine components, such as urticaria dyspnea and angioneuroedema;
• Autoimmune disease or immunodeficiency/immunosuppression;
• Severe chronic diseases, severe cardiovascular diseases, hypertension and diabetes that cannot be controlled by drugs, liver or kidney diseases, malignant tumors, etc;
• Severe neurological disease (epilepsy, convulsions or convulsions) or mental illness;
• Immunosuppressive therapy, cytotoxic therapy, inhaled corticosteroids(excluding allergic rhinitis corticosteroid spray therapy, acute noncomplicated dermatitis superficial corticosteroid therapy) in the past 6 months or plan to receive these treatments during the study period;
• Receipt of blood products within in the past 3 months or plan to receive these treatments during the study period;
• Receipt of other investigational drugs in the past 30 days;
• Receipt of attenuated live vaccines in the past 14 days,or receipt of inactivated or subunit vaccines in the past 7 days;
• Onset of various acute or chronic diseases within 7 days prior to the study;
• Axillary temperature >37.0°C;
• According to the investigator's judgment, the subject has any other factors that are not suitable for participating in the clinical trial.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Experimental group 1 (3-month interval); 100 subjects who have received two doses of COVID-19 vaccine (Vero cell), Inactivated will receive a 3rd dose of the vaccine (3-month interval）.	Biological: COVID-19 Vaccine (Vero cell), Inactivated; The COVID-19 vaccine,inactivated was manufactured by Sinovac Research& Development Co., Ltd.600SU inactivated SARS-CoV-2 CZ strain virus in 0.5 mL of aluminium hydroxide solution per injection.; Other Names: CoronaVac®
Experimental: Experimental group 2 (4-month interval); 100 subjects who have received two doses of COVID-19 vaccine (Vero cell), Inactivated will receive a 3rd dose of the vaccine (4-month interval）.	Biological: COVID-19 Vaccine (Vero cell), Inactivated; The COVID-19 vaccine,inactivated was manufactured by Sinovac Research& Development Co., Ltd.600SU inactivated SARS-CoV-2 CZ strain virus in 0.5 mL of aluminium hydroxide solution per injection.; Other Names: CoronaVac®
Experimental: Experimental group 3 (5-month interval); 100 subjects who have received two doses of COVID-19 vaccine (Vero cell), Inactivated will receive a 3rd dose of the vaccine (5-month interval）.	Biological: COVID-19 Vaccine (Vero cell), Inactivated; The COVID-19 vaccine,inactivated was manufactured by Sinovac Research& Development Co., Ltd.600SU inactivated SARS-CoV-2 CZ strain virus in 0.5 mL of aluminium hydroxide solution per injection.; Other Names: CoronaVac®
Experimental: Experimental group 4 (6-month interval); 100 subjects who have received two doses of COVID-19 vaccine (Vero cell), Inactivated will receive a 3rd dose of the vaccine (6-month interval）.	Biological: COVID-19 Vaccine (Vero cell), Inactivated; The COVID-19 vaccine,inactivated was manufactured by Sinovac Research& Development Co., Ltd.600SU inactivated SARS-CoV-2 CZ strain virus in 0.5 mL of aluminium hydroxide solution per injection.; Other Names: CoronaVac®

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Immunogenicity index-GMT of neutralizing antibodies	GMT of neutralizing antibodies at 14 days after vaccination	At 14 days after vaccination
Immunogenicity index- GMT of neutralizing antibodies	GMT of neutralizing antibodies at 28 days after vaccination	At 28 days after vaccination
Safety index-Incidence of adverse reactions	Incidence of adverse reactions 0~28 days after vaccination	0~28 days after vaccination

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Immunogenicity index-seropositive rate of neutralizing antibodies	Seropositive rate of neutralizing antibodies of neutralizing antibodies before vaccination and at different points after vaccination	Day 0 before vaccination and 14 days, 28 days and 180 days after vaccination
Immunogenicity index-GMT of neutralizing antibodies	GMT of neutralizing antibodies before vaccination and at different points after vaccination.	Day 0 before vaccination and 180 days after vaccination
Immunogenicity index-4-fold increase rate of neutralizing antibodies	4-fold increase rate of neutralizing antibodies at different points after vaccination.	At 14 days and 28 days after vaccination.
Safety index-Incidence of adverse reactions	Incidence of adverse reactions 0~7 days after vaccination.	0~7 days after vaccination
Safety index-Incidence of serious adverse events	Incidence of serious adverse events 6 months after vaccination.	6 months after vaccination

Collaborators and Investigators

• Sponsor: Sinovac Life Sciences Co., Ltd.
• Investigators: Principal Investigator: Jun Yang, Master, Yunnan Provincial Center for Disease Control and Prevention

Study record dates

Study Major Dates

• Study Start (Actual): December 6, 2021
• Primary Completion (Actual): June 30, 2022
• Study Completion (Actual): July 30, 2022

Study Registration Dates

• First Submitted: May 31, 2022
• First Submitted That Met QC Criteria: May 31, 2022
• First Posted (Actual): June 1, 2022

Study Record Updates

• Last Update Posted (Actual): August 11, 2022
• Last Update Submitted That Met QC Criteria: August 9, 2022
• Last Verified: May 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; RNA Virus Infections; Virus Diseases; Infections; Respiratory Tract Infections; Respiratory Tract Diseases; Pneumonia, Viral; Pneumonia; Lung Diseases; COVID-19
• Other Study ID Numbers: PRO-nCoV-4011

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No