COVID-19; Comparative Study of Serum S-reactive IgG4 Antibody Levels, N-reactive IgG Antibody Levels, and S-reactive IgG Antibody Levels in COVID-19 mRNA Vaccine Recipients and Non-Recipients using IgG Antibody Testing

Recruiting

• Conditions: none

• Registration Number: jRCT1030250071

Brief Summary

Not available

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2025-04-30
• Last Update Posted: 2025-05-20

Recruitment & Eligibility

• Status: Recruiting
• Sex: All
• Target Recruitment: 180

Inclusion Criteria

Japanese people (non-naturalized Japanese nationals) who meet the following requirements. We are looking for 20 people each who have not received the mRNA vaccine and who have received 1 to 8 doses of the mRNA vaccine.

1. Those who have not received the mRNA vaccine: 20 people
2. Those who have received 1 dose of the mRNA vaccine: 20 people
3. Those who have received 2 doses of the mRNA vaccine: 20 people
4. Those who have received 3 doses of the mRNA vaccine: 20 people
5. Those who have received 4 doses of the mRNA vaccine: 20 people
6. Those who have received 5 doses of the mRNA vaccine: 20 people
7. Those who have received 6 doses of the mRNA vaccine: 20 people
8. Those who have received 7 doses of the mRNA vaccine: 20 people
9. Those who have received 8 doses of the mRNA vaccine: 20 people

Exclusion Criteria

1. Non-Japanese.
2. Patients currently participating in other clinical trials, or patients who have participated in a clinical trial in the past and for whom more than one month has not passed since the last dose of the test drug.
3. Patients who are unable to register for this study via online medical consultation or online electronic device, or who are unable to enter data or send it via the Internet, either by themselves or their legal representative.
4. Patients who the principal investigator or co-investigator of the study deems inappropriate as subjects.

Study & Design

• Study Type: Observational
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
S-reactive IgG4 antibody		amount of S-reactive IgG4 antibody in blood
N-reactive IgG antibody		amount of N-reactive IgG antibody in blood
S-reactive IgG antibody		amount of S-reactive IgG antibody in blood