WithdrawnNCT05156632Updated Feb 8, 2023

Efficacy,Immunogenicity and Safety of COVID-19 Vaccine , Inactivated Booster Dose in Adults Aged 18 Years and Above

A Phase 3 interventional study of Medium-dosage COVID-19 Vaccine,Inactivated and High-dosage COVID-19 Vaccine,Inactivated in COVID-19, sponsored by Sinovac Research and Development Co., Ltd.. Withdrawn. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2023-02-08.

Sponsored by Sinovac Research and Development Co., Ltd. · Phase 3, Interventional, and Prevention

Why this study was withdrawn

The plan has changed

Phase: Phase 3
Study type: Interventional
Enrollment: 0
Allocation: Randomized
Ages: 18 Years and older
Sex: All

Study summary

Read the detailed description

This is a multi-center, case-driven, randomized, double-blinded, and placebo-controlled Phase Ⅲb clinical trial of COVID-19 Vaccine manufactured by Sinovac Research \& Development Co., Ltd.The purpose of this study is to evaluate the efficacy of the booster dose after two doses of CoronaVac® against RT-PCR confirmed symptomatic COVID-19 cases in participants aged 18 years and above.A total of 13,800 participants aged 18 years and above, who have received 2 doses CoronaVac® in an interval between 21-56 days will be enrolled.Participants will be enrolled and randomly assigned into 3 groups at a ratio of 1:1:1 to receive a booster dose of medium-dose or high-dose COVID-19 Vaccine or placebo 5-8 months after their second dose.Efficacy assessments will include the surveillance for COVID-19-like symptoms, the laboratory confirmation of SARS-CoV-2 infection by RT-PCR, and recording of COVID-19-related hospitalizations.All participants will be monitored for immediate reactions (within 30 minutes) after the booster dose vaccination, adverse events of special interest (AESIs) and serious adverse events (SAEs) for 6 months after booster dose inoculation. In addition,participants in reactogenicity subgroup will be monitored for local and systemic solicited adverse events (AEs) within 7 days and the unsolicited AEs within 28 days.Immunogenicity assessments will be determined by neutralizing and anti-SARS-CoV-2 S-protein antibodies in subgroup participants. The participants in the immunogenicity subgroup will be in the reactogenicity subgroup as well.

Conditions studied

COVID-19

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COVID-19 7,640

In context

COVID-19

7,640 studies on the registry are indexed under COVID-19; 488 are open to participants now.

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Lead sponsor

Sinovac Research and Development Co., Ltd. is the lead sponsor of 22 studies on the registry; none are open to participants now.

Counted across the registry records on this site, refreshed daily.

Who can participate

Ages eligible: 18 Years and older
Sexes eligible: All
Accepts healthy volunteers: Yes

Inclusion criteria

Healthy adults aged 18 years and above, who have received 2 prior doses of CoronaVac® with an interval between those doses of 21-56 days, with the second dose given 5-8 months prior to the day of vaccination in the present study;
The participants are able to understand and sign the informed consent voluntarily;
Female participants who have a negative pregnancy test on the day of vaccination, and not currently breastfeeding;
Must be willing to provide verifiable identification (in accordance with the local regulations), has means to be contacted and to contact the investigator during the study.

Exclusion criteria

Exclusion Criteria:

History of confirmed infection of SARS-CoV-2 prior to randomization;
Any prior administration of another investigational coronavirus vaccine or current/planned simultaneous participation in another interventional study to prevent or treat COVID-19;
Allergy to vaccines or vaccine/placebo ingredients, and serious adverse reactions to vaccines, such as urticaria, dyspnea, angioneurotic edema;
Serious chronic disease, serious cardiovascular disease, hypertension and diabetes that cannot be controlled by drugs, hepatorenal disease, malignant tumor, etc;
Acute central nervous system diseases such as encephalitis/myelitis, acute disseminating encephalomyelitis, and related disorders;
Receipt of blood/plasma products or immunoglobulins in the past 3 months before vaccination;
Participation in other studies involving study intervention within 30 days prior to vaccination;
Receipt of attenuated live vaccines in the past 14 days prior to vaccination;
Receipt of inactivated or subunit vaccines in the past 7 days prior to vaccination;
Acute exacerbation or presentation of stable chronic diseases (including but not limited to asthma, migraine, gastrointestinal disorder, etc);
Acute febrile illness with axillary temperature >37.5°C on the day of vaccination; enrollment could be considered if the fever is absent for 72 hours prior to vaccination;
According to the investigator's judgment, the participant has any other factors that might interfere with the results of the clinical trial or pose additional risk to the participant due to participation in the study

Study design

Phase: Phase 3
Primary purpose: Prevention
Allocation: Randomized
Intervention model: Parallel assignment
Masking: Double (Participant, Investigator)
Enrollment: 0 participants (actual)

Study arms

Experimental
Medium-dose group
4800 participants including 3400 participants aged 18-59 years ,1200 participants aged 60 years and above who have received 2 doses of CoronaVac® (medium-dose COVID-19 Vaccine) in an interval between 21-56 days will receive a booster dose of medium-dose COVID-19 Vaccine 5-8 months after their second dose.
Biological: Medium-dosage COVID-19 Vaccine,Inactivated
Experimental
High-dose group
4800 participants including 3400 participants aged 18-59 years,1200 participants aged 60 years and above who have received 2 doses of CoronaVac® (medium-dose COVID-19 Vaccine) in an interval between 21-56 days will receive a booster dose of high-dose COVID-19 Vaccine 5-8 months after their second dose.
Biological: High-dosage COVID-19 Vaccine,Inactivated
Placebo comparator
Placebo group
4800 participants including 3400 participants aged 18-59 years,1200 participants aged 60 years and above who have received 2 doses of CoronaVac® (medium-dose COVID-19 Vaccine) in an interval between 21-56 days will receive a booster dose of placebo 5-8 months after their second dose.
Biological: Placebo-comparator group

Interventions

BiologicalMedium-dosage COVID-19 Vaccine,Inactivated
The COVID-19 vaccine,inactivated was manufactured by Sinovac Research\& Development Co., Ltd..600SU Inactivated SARS-COV-2 virus in 0·5 mL of aluminium hydroxide solution per injection.
Also known as: Medium-dose CoronaVac®
BiologicalHigh-dosage COVID-19 Vaccine,Inactivated
The COVID-19 vaccine,inactivated was manufactured by Sinovac Research\& Development Co., Ltd.1200SU inactivated virus in 0.5 mL of aluminium hydroxide solution per injection.
Also known as: High-dose CoronaVac®
BiologicalPlacebo-comparator group
The composition is aluminium hydroxide with no antigen ,0 SU/0.5 mL,The appearance of the placebo is consistent with the vaccine, which is a milky-white suspension.
Also known as: Placebo (aluminum hydroxide)

What researchers measure

Primary outcomes

Efficacy index -COVID-19 incidence
COVID-19 incidence per 100 person-years of follow-up based on laboratory confirmed cases in participants aged 18 years and above, 6 months after booster dose
Time frame: 6 months after booster dose

Secondary outcomes

Efficacy index -Confirmed hospitalized/severe/death incidence of COVID-19
Confirmed hospitalized/severe/death COVID-19 incidence per 100 person-years of follow-up based on laboratory confirmed cases, 6 months after booster dose
Time frame: 6 months after booster dose
Safety index-Local reactions
Local reactions for up to 7 days after booster dose
Time frame: Up to 7 days after booster dose
Safety index-Systemic events
Systemic events for up to 7 days after booster dose
Time frame: Up to 7 days after booster dose
Safety index-AEs
AEs for up to 28 days after booster dose
Time frame: Up to 28 days after booster dose
Safety index-SAEs
SAEs for up to 6 months after booster dose
Time frame: Up to 6 months after booster dose

Study locations

No study locations are listed for this record.

Updates

Tracking since Sep 25, 2026

No changes since tracking began. The registry record was last updated on Feb 8, 2023, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗

Registry details

Key details

Study ID: NCT05156632
Lead sponsor: Sinovac Research and Development Co., Ltd.
Responsible party: Sponsor
First posted: Dec 14, 2021
Start date: Feb 20, 2023 (estimated)
Primary completion: Feb 20, 2023 (estimated)
Completion: Feb 20, 2023 (estimated)
Last update: Feb 8, 2023

Study contacts

Javed Khan, Master

principal investigator · Rehman Medical Institute

Oversight

Data monitoring committee: No
FDA-regulated drug: No
FDA-regulated device: No

View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is withdrawn, as verified in Feb 2023. You cannot join it, but the record below documents what was studied.

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