Safety and Immunological Response following homologous or heterologous booster COVID-19 vaccination (3rd dose study)

Safety and Immunological Response following homologous or heterologous booster COVID-19 vaccination (3rd dose study) (extended study of Immunological Responses and safety after COVID-19 vaccination in Healthcare Workers at Siriraj Hospital, Bangkok)

Status

Active, not recruiting

Phases

Phase 2

Study type

Interventional

Source

TCTR

Registry ID

TCTR20210719006

Enrollment

360

Registered

2021-07-19

Start date

2021-12-14

Completion date

Unknown

Last updated

2026-08-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

healthy volunteers healthcare workers

Interventions

Booster with BBIBP-CorV after 2 dose of CoronaVac,Booster with ChAdOx1 after 2 dose of CoronaVac,Booster with 30 mcg BNT162b2 after 2 dose of CoronaVac,Booster with 15 mcg BNT162b2 after 2 dose of Cor

Experimental Biological/Vaccine,Experimental Biological/Vaccine,Experimental Biological/Vaccine,Experimental Biological/Vaccine,Experimental Biological/Vaccine,Active Comparator Biological/Vaccine,Exp

1,2,3,4,5,6,7,8

Eligibility

Sex/Gender

All

Age

18 Years to No maximum

Inclusion criteria

Inclusion criteria: - Males or females at least 18 years of age (inclusive) - Have received 2nd dose of COVID-19 vaccine (CoronaVac or ChAdOx1) for 8-12 weeks earlier - Can understand Thai language through speaking, reading and writing - Able to communicate through electronic tools such as Google form or line - Capable of attending all study visits according to the study schedule - Capable of informed consent and provision of written informed consent before any study procedures

Exclusion criteria

Exclusion criteria: - Have history of severe drug or vaccine allergy (anaphylaxis) - Have detected COVID-19 infection within the last 90 days - Have received blood transfusion, plasma, blood product, blood components, immunoglobulins, antiviral or antibodies within the last 90 days - Have history of cigarettes smoking, alcohol drinking and history of drug abuse - Be pregnant - Have unstable disease or could not control the symptom - Have history of immunodeficiency or use immunosuppressant or steroid drugs - Have any unusual symptoms or medical history that considered unable to participate in the study

Design outcomes

Primary

Measure	Time frame
Adverse events within 7 days after booster vaccine Proportion of Adverse events	—

Secondary

Measure	Time frame
Immunological response including antibody level and cell mediated immune response 2 weeks and 16-20 weeks after vaccine IgG level, NT test, IGRA test	—

Countries

Thailand

Contacts

Public ContactNasikarn Angkasekwinai

Mahidol University

nasikarn.ang@mahidol.ac.th0818708766

Outcome results

None listed

Source: TCTR (via WHO ICTRP) · Data processed: Aug 9, 2026