Safety and Immunological Response following heterologous prime-boost primary series and booster COVID-19 vaccination

Status

Recruiting

Phases

Phase 2

Study type

Interventional

Source

TCTR

Registry ID

TCTR20210720007

Enrollment

270

Registered

2021-07-20

Start date

2021-07-14

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 heterologous prime-boost COVID-19 vaccine

Interventions

Inactivated vaccine/AstraZeneca/mRNA (full dose) ,Inactivated vaccine/AstraZeneca/mRNA (Half dose) ,AstraZeneca/Inactivated vaccine/mRNA (full dose) ,AstraZeneca/Inactivated vaccine/mRNA (half dose) ,

Experimental Biological/Vaccine,Experimental Biological/Vaccine,Experimental Biological/Vaccine,Experimental Biological/Vaccine,Experimental Biological/Vaccine,Experimental Biological/Vaccine,Experime

1,2,3,4,5,6,7,8,9

Eligibility

Sex/Gender

All

Age

18 Years to No maximum

Inclusion criteria

Inclusion criteria: 1. Males or females at least 18 years of age (inclusive) 2. Have not received COVID-19 vaccine or received 1st dose of COVID-19 vaccine (Inactivated vaccine or AstraZeneca) within 4 weeks 3. Can understand Thai language through speaking, reading and writing 4. Able to communicate through electronic tools such as Google form or line. 5. Capable of attending all study visits according to the study schedule 6. Capable of informed consent and provision of written informed consent before any study procedures

Exclusion criteria

Exclusion criteria: 1. Have history of severe drug or vaccine allergy (anaphylaxis) 2. Have detected COVID-19 infection 3. Have history of COVID-19 high risk contact 4. Have received blood transfusion, plasma, blood product, blood components, immunoglobulins, antiviral or antibodies within the last 90 days 5. Have history of cigarettes smoking, alcohol drinking and history of drug abuse 6. Be pregnant 7. Have unstable disease or could not control the symptom 8. Have history of immunodeficiency or use immunosuppressant or steroid drugs 9. Have any unusual symptoms or medical history that considered unable to participate in the study

Design outcomes

Primary

Measure	Time frame
Adverse events 7 days after Vaccination and upto 12 weeks after 2nd dose or 2 weeks after 3rd dose amount of adverse events	—

Secondary

Measure	Time frame
Immune reponse 12 weeks after 2nd dose or 2 weeks after 3rd dose IgG level	—

Countries

Thailand

Contacts

Public ContactSuvimol Niyomnaitham

Mahidol University

suvimol.niy@mahidol.edu0824542896

Outcome results

None listed

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