Long-term Immunogenicity of L-HAV Vaccine Among Healthy Thai Children and Adolescents (NCT07032610) | Clinical Trial Compass
Active — Not RecruitingNot Applicable
Long-term Immunogenicity of L-HAV Vaccine Among Healthy Thai Children and Adolescents
Thailand60 participantsStarted 2025-06-26
Plain-language summary
Hepatitis A virus (HAV) remains a common infection among Thai children. Two types of HAV vaccines are available in Thailand: an inactivated vaccine (I-HAV, administered in two doses 6 months apart) and a live-attenuated vaccine (L-HAV, administered as a single dose). However, neither vaccine is currently included in Thailand's Expanded Programme on Immunization (EPI). In 2024, a randomized, active-controlled, open-label, non-inferiority trial was conducted to compare the immunogenicity and safety of the two-dose I-HAV with the single-dose L-HAV in healthy Thai children and adolescents aged 18 months to 18 years. This study aims to evaluate the long-term seropositive rate and immunogenicity of anti-HAV antibodies in this population following a single dose of L-HAV.
Who can participate
Age range
18 Months – 20 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion Criteria:
* Thai children and adolescents who previously participated in the previous RCT study
* Previously randomized to receive one dose of L-HAV vaccine within the past 1 year (+/- 3 months)
* Participants and/or caregivers gives written inform consent/assent form
Exclusion Criteria:
* History of acute illness within 4 weeks prior to study enrollment
* Has a history of illness or a diagnosis consistent with hepatitis A after receiving the live attenuated hepatitis A vaccine as part of participation in a previous research study
* Has a history of receiving any additional hepatitis A vaccine after participating in the previous research study
* Presence of fever (body temperature ≥38.0°C), jaundice, or yellowing of the eyes within 4 weeks prior to study enrollment
* Have any condition that, in the opinion of the site investigator, would compromise the subject's ability to participate in the study
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.