An observational study in Enterovirus Infections, sponsored by Enimmune Corporation. Completed at 1 site in Vietnam. Open to participants aged 2 Years to 9 Years. Per ClinicalTrials.gov, last updated 2026-09-11.
Sponsored by Enimmune Corporation · Observational
The main study was a randomized, multi-nation, multi-centered, double-blinded, phase III study on subjects aged 2 months to \<6 years old (\<72 months). Two parts were conducted in Taiwan (Group A) and Vietnam (Group B). This extended study involved the subjects enrolled in the EV-BR1701 Group B1 who received any IP injections. For Group B, out of 2727 subjects enrolled from June 2022 to Jul 2023, 241 subjects of Group B1 would be assigned to this extension study. The extension study aimed to evaluate the immunogenicity persistence after EnVAX-A71 vaccination.
The subjects of Group B1 would be recalled for phlebotomy and immunogenicity analysis. The subjects would not receive further study EV71 vaccines in the extension study.
The principal investigators (PIs) and study coordinators (SCs) of the original medical center would contact the subject's guardians/legal representative by phone to return to the medical center for phlebotomy.
Informed consent would be provided to the guardians/legal representative of the subjects, and the eligibility of subjects would be verified on the day of the recall visit.
After the subject was evaluated by the PI and meets the phlebotomy requirements, the subject's guardian/legal representative would be asked to sign the informed consent form, and the new subject's number would be given.
About 3-4 mL of blood would be collected from each subject, and the serum would be collected and sent to the designated central laboratory for testing. The validated neutralizing antibody (NTAb) analysis method would be used to determine the neutralizing antibody titer.
The NTAb titer results would be directly sent to the CRO Data Manager Team, and statistical analysis for immunogenicity would be performed and reported after the main study was complete.
48 studies on the registry are indexed under Enterovirus Infections; 3 are open to participants now.
This study's enrollment of 126 is below the median of 212 across 12 observational studies indexed under Enterovirus Infections.
Browse Enterovirus Infections studies →Enimmune Corporation is the lead sponsor of 5 studies on the registry; none are open to participants now.
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The main study is a randomized, multi-nation, multi-centered, double-blinded, phase III study on subjects aged 2 months to \<6 years old (\<72 months). Two parts are conducted in Taiwan (Group A) and Vietnam (Group B). This extended study involves the subjects enrolled in the EV-BR1701 Group B1 who received any IP injections. For Group B, out of 2727 subjects enrolled from June 2022 to Jul 2023, 241 subjects of Group B1 will be assigned to this extension study. The extension study aims to evaluate the immunogenicity persistence after EnVAX-A71 vaccination.
The subjects of Group B1 will be recalled for phlebotomy and immunogenicity analysis. The subjects will not receive further study EV71 vaccines in the extension study.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
This extension study aims to assess the long-term immunogenicity of EnVAX-A71 vaccination in children aged two months to under six years old.
To determine the serum EV71-specific neutralizing antibody (NTAb) titers by measuring the GMT, SCRa, and SPRb for those subjects from Part B1 upon recall.
Time frame: From Dec-2024 to Jan-2025
Plan to share: Undecided
No publications or documents are linked to this record.
Ran from Dec 2024 to primary completion in Jan 2025, 0 months.
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This study is completed, as verified in Jun 2026. You cannot join it, but the record below documents what was studied.
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Enimmune Corporation