Phase Ⅲ Trial of Group ACYW135 Meningococcal Conjugate Vaccine in Children Aged 2-6 Years (NCT07505888) | Clinical Trial Compass
Not Yet RecruitingPhase 3
Phase Ⅲ Trial of Group ACYW135 Meningococcal Conjugate Vaccine in Children Aged 2-6 Years
660 participantsStarted 2026-03-22
Plain-language summary
The goal of this clinical trial is to evaluate the immunogenicity and safety of an investigational group ACYW135 meningococcal conjugate vaccine in healthy children aged 2 to 6 years.
The main questions it aims to answer are:
Is the immune response induced by the investigational vaccine non-inferior to that of the licensed control vaccine, as measured by serum antibody levels? What safety profile does the investigational vaccine have in this pediatric population? Researchers will compare the investigational vaccine group with the control group (licensed ACYW135 polysaccharide vaccine) to determine if the new vaccine provides comparable immune protection with an acceptable safety profile.
Participants will:
Receive a single dose of either the investigational vaccine or the control vaccine by intramuscular injection; Provide two blood samples (before vaccination and 30 days after) for antibody testing; Have their vaccination site and overall health monitored for AE/AR immediately after injection, for 7 days and for 30 days through diary card and follow-up contacts; Be followed for serious adverse events for 6 months after vaccination. A total of 660 participants will be enrolled and randomly assigned in a 1:1 ratio to either the investigational group or the control group.
Who can participate
Age range
2 Years – 6 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
. Healthy participants aged 2 to 6 years.
. The participant's legal guardian is capable of understanding and voluntarily signs the informed consent form.
. Willing and able to comply with all scheduled visits, sample collection, vaccination, and other trial procedures.
. Provision of legal identification documentation.
Exclusion criteria
. History (or suspected history) of meningococcal disease.
. History of infantile wheezing/asthma; history of allergy to the vaccine or any vaccine components (Group A/C/Y/W135 meningococcal capsular polysaccharide, mannitol, sucrose, sodium dihydrogen phosphate monohydrate, disodium hydrogen phosphate dodecahydrate, sodium chloride, water for injection), such as urticaria, dyspnea, angioedema; or other serious adverse reactions following prior vaccination.
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.
What they're measuring
1
Seroconversion rates (%) of Nm antibodies for serogroups A, C, Y, W135
Timeframe: Day 30 after vaccination
2
GMTs (1:) of Nm antibodies for serogroups A, C, Y, W135
. Prior vaccination with Group A or Group A/C meningococcal polysaccharide vaccine with an interval ≤1 year since the most recent dose; prior vaccination with any meningococcal polysaccharide/polysaccharide conjugate vaccine other than Group A or Group A/C meningococcal polysaccharide vaccines (including but not limited to: ACYW135 meningococcal polysaccharide vaccine, Group A/C meningococcal polysaccharide conjugate vaccine, ACYW135 meningococcal polysaccharide conjugate vaccine).
. Presence of autoimmune diseases or immunodeficiency diseases (including but not limited to systemic lupus erythematosus, ankylosing spondylitis, autoimmune thyroid disease, asplenia, functional asplenia, HIV infection in the participant or the participant's mother).
. Coagulation disorders (e.g., coagulation factor deficiency, platelet abnormalities) or history of significant bleeding, hematoma, or ecchymosis following intramuscular injection or venipuncture.
. Presence of poorly controlled chronic diseases or history of serious illnesses, including but not limited to cardiovascular diseases, metabolic diseases, hematological diseases, hepatorenal diseases, gastrointestinal diseases, respiratory diseases, malignancies, or history of major organ transplantation.
. Severe congenital anomalies, genetic defects, or malnutrition.
. Presence of or history of severe neurological disorders \[epilepsy, convulsions or seizures (excluding history of febrile seizures)\] or psychiatric disorders, or family history of psychiatric disorders.