A Phase Ⅲ Clinical Trial of Recombinant COVID-19 Trivalent (XBB+BA.5+Delta) Protein Vaccine (Sf9 Cell) in Booster Vaccination

Study Overview
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Brief Summary
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A Phase Ⅲ Clinical Trial of Recombinant COVID-19 Trivalent (XBB+BA.5+Delta) Protein Vaccine (Sf9 Cell) in Booster Vaccination to Evaluate Efficacy, Safety and Immunogenicity

Detailed Description
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A Multicenter, Randomized, Double-Blind, Controlled, Phase Ⅲ Clinical Trial of Recombinant COVID-19 Trivalent (XBB+BA.5+Delta) Protein Vaccine (Sf9 Cell) in Booster Vaccination to Evaluate Efficacy, Safety and Immunogenicity in Healthy Population Aged 18 Years Old and Above

Official Title
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A Multicenter, Randomized, Double-Blind, Controlled, Phase Ⅲ Clinical Trial of Recombinant COVID-19 Trivalent (XBB+BA.5+Delta) Protein Vaccine (Sf9 Cell) in Booster Vaccination to Evaluate Efficacy, Safety and Immunogenicity in Population Aged 18 Years Old and Above

Conditions
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COVID-19

Intervention / Treatment
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* Biological: High dose of Recombinant COVID-19 Trivalent (XBB+BA.5+Delta) Protein Vaccine (Sf9 Cell)
* Biological: Low dose of Recombinant COVID-19 Trivalent (XBB+BA.5+Delta) Protein Vaccine (Sf9 Cell)
* Biological: control group
* Biological: Placebo group


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subjects aged 18 years and above, including those with underlying diseases and immunocompromised subjects. Basic or booster immunization with COVID-19 vaccine ≥6 months. ≥3 months of SARS-CoV-2 infection history, or never infected. Have the ability to understand research procedures, with informed consent, voluntarily sign informed consent, and be able to comply with the requirements of clinical research protocols. Exclusion Criteria: Axillary temperature ≥37.3℃. SARS-CoV-2 antigen or nucleic acid screening positive within the last 48 hours. Anti-SARS-CoV-2 IgM antibody was positive during the screening period. It is in the advanced stage of malignant tumor and the disease control is unstable. Female pregnancy (pregnancy test results are positive), lactation period. Have serious cardiovascular diseases, such as arrhythmia, conduction block, myocardial infarction, heart failure, severe hypertension, and can not be controlled by drugs. Have other serious chronic conditions such as uncontrolled asthma, diabetes, chronic obstructive pulmonary disease, pulmonary embolism, chronic kidney disease requiring dialysis, cirrhosis of the liver, convulsions, epilepsy and other neurological/psychiatric conditions. Have been diagnosed with congenital or acquired immunodeficiency, HIV infection. People who are allergic to any component of the investigational vaccine have a history of more severe allergies or allergic reactions to the vaccine in the past. Congenital or acquired angioedema/neuroedema. Asplenia or functional asplenia. Thrombocytopenia or other clotting disorders (which may cause intramuscular injection contraindications). Received another investigational drug within 1 month prior to receiving the investigational vaccine. Received subunit or inactivated vaccine within 14 days prior to receiving the investigational vaccine, or received live attenuated vaccine within 1 month. Fertile female subjects did not use effective contraception within 1 month prior to enrollment. Fertile female and male subjects have pregnancy plans and sperm/egg donation plans from the screening period to 3 months after immunization. Abnormal laboratory test results during the screening period, which were judged by the researcher to be unsuitable for the study vaccine. Medical, psychological, social, or other conditions that, in the investigator's judgment, are inconsistent with the protocol or affect the subject's signing of informed consent.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Experimental group 1<br>high dose | Biological: High dose of Recombinant COVID-19 Trivalent (XBB+BA.5+Delta) Protein Vaccine (Sf9 Cell)<br>* boost with high dose of Recombinant COVID-19 Trivalent (XBB+BA.5+Delta) Protein Vaccine (Sf9 Cell)<br>|
| Experimental: Experimental group 2<br>low dose | Biological: Low dose of Recombinant COVID-19 Trivalent (XBB+BA.5+Delta) Protein Vaccine (Sf9 Cell)<br>* boost with low dose of Recombinant COVID-19 Trivalent (XBB+BA.5+Delta) Protein Vaccine (Sf9 Cell)<br>|
| Active Comparator: Control group<br>Control group | Biological: control group<br>* boost with Recombinant Variant COVID-19 Vaccine(sf9 cell)<br>|
| Placebo Comparator: Placebo control group<br>Placebo control group | Biological: Placebo group<br>* saline<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Efficacy against COVID-19 | Efficacy against the first occurrence of a virologically confirmed (PCR-positive) case of symptomatic COVID-19, regardless of severity, 14 days after booster vaccination. | 14 days after vaccination | 
| AE and AR | Incidence of adverse events (AE) and adverse reactions (AR) 0-7 days after booster vaccination. | 0-7 days after vaccination | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Secondary Efficacy against COVID-19 | Efficacy against the first occurrence of a virologically confirmed (PCR-positive) case of symptomatic COVID-19 > 7 days after booster vaccination in subjects, regardless of severity. | >7 days after booster vaccination | 
| Secondary Efficacy against COVID-19 | Efficacy against first occurrence of virologically confirmed (PCR-positive) cases of moderate/severe COVID-19 caused by SARS-CoV-2 infection, cases of hospitalization due to COVID-19, and cases of death due to COVID-19, > 7 days and > 14 days after booster vaccination | > 7 days and > 14 days after booster vaccination | 
| Secondary Safety | Incidence of adverse events (AE) and adverse reactions (AR) 0-30 days after booster vaccination. | 0-30 days after booster vaccination | 
| Secondary Safety | Incidence of serious adverse events (SAE) and adverse events of special interest (AESI) within 12 months after booster vaccination. | within 12 months after booster vaccination | 
| Secondary Immunogenicity indicator 1 | The geometric mean titer (GMT), seroconversion rate and geometric mean fold increase (GMI) of neutralizing antibodies against SARS-CoV-2 variants (based on the current variants at same time) on day 14, day 30 and 3 months after booster vaccination. | day 14, day 30 and 3 months after booster vaccination | 
| Secondary Immunogenicity indicator 2 | Geometric mean titer (GMT), seroconversion rate and geometric mean fold increase (GMI) of anti-SARS-CoV-2 specific binding antibodies were measured on day 14, day 30 and 3 months after booster vaccination. | day 14, day 30 and 3 months after booster vaccination |