Immune responses, boosting effects of adults previously received two doses of inactivated COVID-l9 vaccines and third doses of any COVID-I9 vaccine with additional mRNA COVID-19 vaccine boost after one year

Phase 2

Completed

• Conditions: Primary Objectives:To evaluate the antibody responses and long-term immunogenicity both humoral and T-cell response after boosting of bivalent mRNA vaccine approximately one year of those who have previously received two doses of Sinovac or Sinoharm and third or forth doses of COVID vaccines of any platforms during the current Omicrons variants.SafetyTo assess the safety and tolerability of the mRNA booster dose; Sinovac or Sinoharm and third or forth doses of COVID vaccines; mRNA boost

• Registration Number: TCTR20230811004
• Lead Sponsor: ational Research Council of Thailand (NRCT)

Brief Summary

Not available

Detailed Description

Not available

Study Timeline

• Study Start: 2023-08-11
• Study Completion: 2023-10-03
• Last Update Posted: 19 August 2024

Recruitment & Eligibility

• Status: Completed
• Sex: All
• Target Recruitment: 198

Inclusion Criteria

1. Adult male or female aged 18 years or more on the day of signing the ICF confirmed by identification cards.
2. Verified, documentation of past COVID-19 vaccination, received two doses of inactivated COVID vaccine and any third or fourth booster dose for intervals more than 12 months.
3. Women who are test negative with a highly sensitive urine pregnancy test at Visit 1
4. Subject has provided written informed consent prior to performance of any study-specific procedures and is willing and has means to be contacted and to contact the investigator during the study.
5. In the clinical judgment of investigator, the participant is in good health or has stable and well-controlled medical conditions.

Exclusion Criteria

1. The participant has a clinically significant acute illness (this does not include minor illnesses such as diarrhea or mild upper respiratory tract infection), or is a patient under investigation (PUI) or has a body temperature more than 38.0 degree C (100.4 degree F) within 24 hours prior to the planned study vaccination. Assignment may be made at a later date is permitted at the discretion of the investigator.
2. Contraindication to mRNA COVID vaccine according to labelling of the product. For example, if the participant has a known or suspected allergy or history of anaphylaxis or other serious adverse reactions to vaccines or their excipients.
3. Pregnant
4. Participant has a history or current condition as follows
a. Any confirmed or suspected immunosuppressive or immunodeficient state.
b. Acute polyneuropathy (e.g. Guillain-Barre syndrome).
c. Contraindication to IM injections and blood draws e.g., bleeding disorders.
d. An underlying clinically significant acute or chronic medical condition or physical examination findings for which, in the opinion of the investigator, participation would not be in the best interest of the participant (e.g., compromise the well-being) or that could prevent, limit, or confound the protocol-specified assessments.
e. Major psychiatric illness which in the opinion of investigator would compromise the safety or compliance of participants with the study procedures.
5. If the participant received or plans to receive:
a. Licensed live attenuated vaccines - within 28 days before or after planned administration of study vaccine.
b. Other licensed (not live) vaccines - within 14 days before or after planned administration of the study vaccine.
c. Treatment with immunoglobulins (Ig) in the 3 months or exogenous blood products (autologous blood transfusions are not exclusionary) in the 4 months before the planned administration of the study vaccine or has any plans to receive such treatment during the study.
6. If the participant cannot communicate reliably with the investigator, or, in the opinion of the investigator, is unlikely to adhere to the requirements of the study or is unlikely to complete the full course of vaccination and observation.
7. Employee of the study center directly involved with the proposed study or with study investigators

Study & Design

• Study Type: Interventional
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
GMTs with CIs and GMFR from baseline (V1) with CI, and Percentage of subjects with IgG seroresponses and 95% CI of 4-fold increase from baseline (V1) Day 0,28,90 Anti-S IgG antibody titers measured by ELISA, Neutralizing antibody titers by pseudovirus-based neutralization assay. T-Cell-mediated immunity using an interferon-gamma release ELISA.

Secondary Outcome Measures

Name	Time	Method
/A N/A N/A