A Phase 3 interventional study of EV71 vaccine and Placebo in Enterovirus Infections, sponsored by Enimmune Corporation. Completed at 9 sites in 2 countries. Open to participants aged 2 Months to 71 Months, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-09-11.
Sponsored by Enimmune Corporation · Phase 3, Interventional, and Prevention
The objectives of this study are to evaluate the EV71vaccine efficacy, immune response and safety profiles after two injections of the cell culture-based inactivated EV71 vaccine with adjuvant Al(OH)3 administrated in pediatric population aged 2 months to 6 years old.
The clinical trial designed in this Study is a placebo-controlled, double-blinded Phase III and is aimed to evaluate the vaccine efficacy, safety, immunogenicity and immune persistence of cell culture-based inactivated EV71 vaccine in children age of 2 months to \<6 years old. Two doses of Alum-adjuvanted 1.0 μg per dose of EV71 vaccine candidate will be administrated to subjects. The efficacy will be evaluated within a two year period after receiving 2-regimen vaccination by comparing the EV71-associated disease rates between the vaccine and placebo groups. Whereas, the immunogenicity will be assessed on Day 56 and Day 196, and the immune persistence will be evaluated on Day 392. Safety will be followed up to Day 392.
48 studies on the registry are indexed under Enterovirus Infections; 3 are open to participants now.
This study's enrollment of 3,982 is above the median of 132 across 31 interventional 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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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.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
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.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Biological: EV71 vaccine
Biological: Placebo
EV71 vaccine (\[1 μg total protein + adjuvant 150 μg AI(OH)3\] per dose) Two vaccinations at 28 days apart
Placebo (\[ adjuvant 150 μg AI(OH)3\] per dose) Two vaccinations at 28 days apart
The incidence rate of Hand, Foot and Mouth disease caused by EV71 after the second vaccination.
Evaluate the efficacy of EV71 vacccine against HFMD caused by EV71
Time frame: From 28 days after the second vaccination to two year
Serum neutralizing antibody titers (NT) induced by the EV71 vaccine
Evaluate the immunogenicity by the response rate
Time frame: 28 days after the second vaccination
The incidence rate of the severe complications and hospitalization of EV71 associated HFMD/HA disease after the second vaccination.
1. Evaluate the efficacy of vaccination against the severe complications, including neurologic, pulmonary edema, and cardiorespiratory failure, of EV71 associated HFMD/HA diseases after completion of full vaccination. 2. Evaluate the efficacy of vaccination against the hospitalization of EV71 associated HFMD/HA diseases after completion of full vaccination.
Time frame: From 28 days after the second vaccination to two year
Serum neutralizing antibody titers (NT) induced by the EV71 vaccine
1. Evaluate the immunogenicity of EV71 vaccine with two-dose regimen. 2. Evaluate the immune persistence of EV71 vaccine with two-dose regimen. 3. Evaluate lot-to-lot consistency by comparing the immunogenicity induced by 3 independent EV71 vaccines.
Time frame: Day 0,56,196,and 392
Adverse events of EV71 vaccine
1. Occurrence and severity of solicited injection site relations and general reactions within 7 days following each injection. 2. Occurrence and severity of unsolicited adverse events within 28 days following each injection. 3. Occurrence and relations with vaccination of some special AE during the 6-months follow-up period (up to Day 196). 4. Occurrence and relations with vaccination of serious adverse events (SAEs) during the one year follow-up period (up to Day 392).
Time frame: Day 0 to Day 392
Plan to share: Undecided
Ran from Jun 2018 to primary completion in Jul 2024, 73 months.
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Studies of the drug tested here: Enterovirus 71 vaccine
Enimmune Corporation