Immune response after two doses of COVID-19 vaccination

JRCT ID: jRCT1051210161

Registered date:23/01/2022

Basic Information

• Recruitment status: Recruiting
• Health condition(s) or Problem(s) studied: Coronavirus Disease 2019
• Date of first enrollment: 24/01/2022
• Target sample size: 600
• Study type: Observational

Outcome(s)

• Primary Outcome: Humoral immune response: changes in antibody titer against SARS-CoV2-Spike protein

Secondary Outcome

(1) Humoral immune response: changes in neutralizing antibody titer against SARS-CoV2
(2) Vaccine effectiveness against laboratory-confirmed COVID-19 (including PCR positive, antigen-testing positive, and serological infection)
(3) Vaccine effectiveness against COVID-19-like diseases
(4) Occurrence of adverse reactions after vaccination
(5) Occurrence of diseases suspected to be caused by vaccination

[Exploratory outcome(s)]
(1) Cell-mediated immunity: SARS-CoV-2 S antigen-specific T cell and B cell function
(2) Antibody subclasses

Key inclusion & exclusion criteria

• Age minimum: >= 20age old
• Age maximum: Not applicable
• Gender: Both

Include criteria

Those who meet all of the following 1) to 6)

1) Persons who meet any of the following (a), (b) and (c)
(a) Participants of "Prospective cohort study of effectiveness and safety of COVID-19 vaccines in Osaka, Japan" *
(b) Staff of Osaka City (Metropolitan) University Hospital
(c) Faculty / Students of Osaka City (Metropolitan) University School of Medicine / Graduate School of Medicine

* Approval number by Osaka City (Metropolitan) University Hospital Certified Review Board: OCU010E, jRCT registration number: jRCT105120014

2) Aged 20 years or older

3) Those who have received two doses of COVID-19 vaccines

4) Those who have passed 5 months since the second dose of COVID-19 vaccines

5) Those who are expected to be able to provide their blood in a predefined number of times during the study period

6) Persons who have voluntarily provided written informed consent for participation

Exclude criteria

Persons who meet any of the following 1) 2)

1) Those who have received pre-licensure COVID-19 vaccines in the past (e.g., participation in clinical trials before licensure)

2) Those who are judged to be ineligible for research by the principal investigator or the investigator

Related Information

• Primary Sponsor: Kayeka Hiroshi
• Secondary Sponsor: Hirota Yoshio,Fukushima Wakaba