Sequential Immunization With Recombinant Adenovirus Type-5-vectored COVID-19 Vaccine in Health Adults Based on 3 Doses Inactivated COVID-19 Vaccine

Study Overview
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Brief Summary
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COVID-19 is a novel coronavirus infection caused by respiratory droplets and contact transmission. With the spread of the epidemic, it has become a serious threat to global public health. China has launched a full range of vaccination including the third dose of homologous and sequential booster immunization. To further improve COVID-19 vaccine immunization strategy, we start the clinic research about sequential Immunization With Recombinant Adenovirus Type-5-vectored COVID-19 Vaccine in Health Adults Based on 3 Doses Inactivated COVID-19 Vaccine in Zhejiang province.

Official Title
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Immunogenicity and Safety of a Recombinant Adenovirus Type-5-vectored COVID-19 Vaccine in Healthy Adults (18-80 Years Old) Finished 3 Doses Inactivated COVID-19 Vaccine: a Randomised, Double-blind, Parallel Controlled, Clinic Trial

Conditions
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Immunogenicity and Safety of a Recombinant Adenovirus Type-5-vectored COVID-19 Vaccine Using for Sequential Immunization

Intervention / Treatment
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* Biological: Recombinant adenovirus type-5-vectored COVID-19 vaccine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Volunteers aged 18 and above at the time of screening; Obtain the informed consent of the volunteers and sign the informed consent; Volunteers are able and willing to comply with the requirements of the clinical trial protocol and complete the 6-month study follow-up; Have received 3 doses of Sinovac/Beijing Biological Novel Coronavirus inactivated vaccine with an interval of 6-9 months. Exclusion Criteria: Patients with history or family history of convulsion, epilepsy, encephalopathy and mental illness; Those who are allergic to any of the components of the study vaccine, have had a severe allergic reaction to the vaccine in the past, a history of allergy or asthma; Serious adverse events related to vaccination occurred after previous vaccination; 4) Positive urine pregnancy test in women during lactation or childbearing age; 5) Acute febrile disease, infectious disease, SARS history; 6) Axillary body temperature > 37.0℃; 7) Suffering from serious cardiovascular diseases, such as arrhythmia, conduction block, myocardial infarction, severe hypertension and uncontrolled medication (systolic blood pressure ≥180mmHg and/or diastolic blood pressure ≥110mmHg when measured on site); 8) Patients with serious chronic diseases that are in the advanced stage and cannot be controlled smoothly, such as diabetes and thyroid diseases; 9) Congenital or acquired angioedema/neuroedema; 10) Urticaria 1 year before receiving the test vaccine; 11) No spleen or functional no spleen; 12) Patients with chronic obstructive pulmonary disease, pulmonary fibrosis and other pulmonary abnormalities; 13) History of novel coronavirus infection/illness; 14) Have traveled to medium or high risk areas or left the country in the past 21 days; have a history of novel Coronavirus 2019-epidemiological contact; 15) The researcher made a judgment based on various medical, psychological, social or other conditions that might be contrary to the test protocol or affect the subjects to sign informed consent.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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: Recombinant adenovirus type-5-vectored COVID-19 vaccine<br> | Biological: Recombinant adenovirus type-5-vectored COVID-19 vaccine<br>* One dose COVID-19 vaccine<br>|
| Active Comparator: Inactivated COVID-19 vaccine<br> | Biological: Recombinant adenovirus type-5-vectored COVID-19 vaccine<br>* One dose COVID-19 vaccine<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of adverse reactions (AR) in 0-14 days after immunization | Incidence of adverse reactions (AR) | 14 days | 
| Geometric mean titer (GMT) of neutralizing antibody against SARS-COV-2 at 14 days after immunization | Geometric mean titer (GMT) of neutralizing antibody against SARS-COV-2 | 14 days |