Immunogenicity and Safety of I-HAV in Healthy Thai Children and Adolescents Lacking Protective Antibody After L-HAV

NCT ID: NCT06978621

Last Updated: 2025-06-17

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

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Recruitment Status

RECRUITING

Clinical Phase

PHASE3

Total Enrollment

36 participants

Study Classification

INTERVENTIONAL

Study Start Date

2025-05-25

Study Completion Date

2025-09-30

Brief Summary

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Hepatitis A virus (HAV) remains a common infection in Thai children. Two HAV vaccines are available: inactivated vaccine (I-HAV, 2 doses) and live-attenuated vaccine (L-HAV, single dose), but neither is included in Thailand's national immunization program. Our previous randomized, active-controlled, open-label, non-inferiority trial trial found that some participants remained seronegative after one L-HAV dose (anti-HAV IgG \<1 S/CO) (preliminary data). This study aims to evaluate the immunogenicity and safety of an additional dose of I-HAV in healthy Thai children and adolescents who did not develop protective antibody levels after a single dose of L-HAV.

Detailed Description

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Hepatitis A virus (HAV) infection remains a common cause of viral hepatitis among children and adolescents in developing countries, including Thailand. Currently, two types of HAV vaccines are available in Thailand; (1) inactivated HAV vaccine (I-HAV) which is recommended as a 2-dose series administered 6 months apart, approved for use in children aged 1 year and older, and (2) live-attenuated HAV vaccine (L-HAV) which is recommended as a single dose, approved for children aged 18 months and older. However, as neither vaccine is included in Thailand's Expanded Programme on Immunization (EPI), the national vaccination coverage remains suboptimal.

In 2024, the investigators conducted a randomized, active-controlled, open-label, non-inferiority trial to compare the immunogenicity and safety of the currently marketed I-HAV and L-HAV in healthy Thai children and adolescents aged 18 months to 18 years. Preliminary results showed that a proportion of participants remained seronegative following a single dose of L-HAV (anti-HAV IgG \<1 S/CO). Based on these findings, the investigators hypothesize that an additional dose of I-HAV may be necessary to achieve adequate seroprotection in this population. Therefore, the aim of this study is to evaluate the immunogenicity and safety of an additional dose of I-HAV in healthy Thai children and adolescents who did not develop protective antibody levels after a single dose of L-HAV.

Conditions

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Hepatitis A Hepatitis A Virus Vaccine-Preventable Diseases

Study Design

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Allocation Method

NA

Intervention Model

SINGLE_GROUP

Primary Study Purpose

PREVENTION

Blinding Strategy

NONE

Study Groups

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Inactivated HAV vaccine (I-HAV)

An additional dose of inactivated hepatitis A vaccination for participants who have seronegative (anti-HAV IgG \<1 S/CO) at baseline (1 year after a single dose of live-attenuated hepatitis A vaccine).

Group Type EXPERIMENTAL

Inactivated hepatitis A vaccine (I-HAV)

Intervention Type BIOLOGICAL

A formaldehyde-inactivated hepatitis A virus (HM175 hepatitis A virus strain)

Dose and administration: 0.5 mL intramuscular injection for participants age \<=18 years, and 1.0 mL intramuscular injection for participants age 19 years and above.

Interventions

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Inactivated hepatitis A vaccine (I-HAV)

A formaldehyde-inactivated hepatitis A virus (HM175 hepatitis A virus strain)

Dose and administration: 0.5 mL intramuscular injection for participants age \<=18 years, and 1.0 mL intramuscular injection for participants age 19 years and above.

Intervention Type BIOLOGICAL

Eligibility Criteria

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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 (+/- 2 months)
* Have not demonstrate a seropositivity against HAV (anti-HAV IgG \<1 S/CO) at 1 month after L-HAV vaccination
* 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
* Has underlying conditions including thrombocytopenia, coagulopathy, hemophilia A or B, neurological disorders, immunodeficiency disorders, chronic liver disease, or chronic hepatitis B or C infection
* Has received immunosuppressive agents, immunomodulatory agents, or high-dose corticosteroids (greater than 2 mg/kg/day or more than 20 mg/day) for more than 14 consecutive days within 6 months prior to study enrollment
* Has received blood products or blood components, including immunoglobulins, within 6 months prior to study enrollment
* Has received other live vaccines within 30 days prior to study enrollment
* Has history of allergy to vaccines or any vaccine components, such as aluminum hydroxide, 2-phenoxyethanol, neomycin, formaldehyde, or gentamicin sulfate, or has history of severe allergic reactions (e.g., anaphylaxis) to any vaccines
* Women planning for pregnancy, pregnant women or lactating women
* Women in childbearing age who cannot use contraceptive methods during study participation
* Is concurrently involved in other clinical trials in which receiving an investigational vaccine or study drug as part of study participation
* Have any condition that, in the opinion of the site investigator, would compromise the subject's ability to participate in the study
Minimum Eligible Age

18 Months

Maximum Eligible Age

20 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

Yes

Sponsors

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Faculty of Medicine, Chiang Mai University

UNKNOWN

Sponsor Role collaborator

Chiang Mai University

OTHER

Sponsor Role lead

Responsible Party

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Tavitiya Sudjaritruk

Associate Professor

Responsibility Role PRINCIPAL_INVESTIGATOR

Principal Investigators

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Tavitiya Sudjaritruk, MD, PhD

Role: STUDY_CHAIR

Department of Pediatrics, Faculty of Medicine, Chiang Mai University

Natchaya Kunanitthaworn, MD

Role: PRINCIPAL_INVESTIGATOR

Department of Pediatrics, Faculty of Medicine, Chiang Mai University

Locations

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Department of Pediatrics, Faculty of Medicine, Chiang Mai University

Chiang Mai, , Thailand

Site Status RECRUITING

Countries

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Thailand

Central Contacts

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Tavitiya Sudjaritruk, MD, PhD

Role: CONTACT

+66-53-936471

Natchaya Kunanitthaworn, MD

Role: CONTACT

+66-53-936461

Facility Contacts

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Tavitiya Sudjaritruk, MD, PhD

Role: primary

+66-53-93-6471

References

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Kunanitthaworn N, Mueangmo O, Saheng J, Wongjak W, Lertsiriladakul T, Chaito T, Nantarat P, Sudjaritruk T. Seroprevalence of hepatitis A virus antibodies among children and adolescents living in Northern Thailand: an implication for hepatitis A immunization. Sci Rep. 2023 Oct 13;13(1):17432. doi: 10.1038/s41598-023-44643-0.

Reference Type BACKGROUND
PMID: 37833325 (View on PubMed)

Ma F, Yang J, Kang G, Sun Q, Lu P, Zhao Y, Wang Z, Luo J, Wang Z. Comparison of the safety and immunogenicity of live attenuated and inactivated hepatitis A vaccine in healthy Chinese children aged 18 months to 16 years: results from a randomized, parallel controlled, phase IV study. Clin Microbiol Infect. 2016 Sep;22(9):811.e9-811.e15. doi: 10.1016/j.cmi.2016.06.004. Epub 2016 Jun 23.

Reference Type BACKGROUND
PMID: 27345175 (View on PubMed)

Liu XE, Wushouer F, Gou A, Kuerban M, Li X, Sun Y, Zhang J, Liu Y, Li J, Zhuang H. Comparison of immunogenicity between inactivated and live attenuated hepatitis A vaccines: a single-blind, randomized, parallel-group clinical trial among children in Xinjiang Uighur Autonomous Region, China. Hum Vaccin Immunother. 2013 Jul;9(7):1460-5. doi: 10.4161/hv.24366. Epub 2013 Apr 9.

Reference Type BACKGROUND
PMID: 23571173 (View on PubMed)

Other Identifiers

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PED-2568-0180

Identifier Type: -

Identifier Source: org_study_id

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