A Phase 1 interventional study of high-dose Group ACYW135X Meningococcal Conjugate Vaccine and medium-dose Group ACYW135X Meningococcal Conjugate Vaccine in Meningococcal Meningitis, sponsored by Sinovac Life Sciences Co., Ltd.. Not yet recruiting. Open to participants aged 2 Years to 59 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-01-28.
Sponsored by Sinovac Life Sciences Co., Ltd. (part of Sinovac Biotech Co., Ltd) · Phase 1, Interventional, and Prevention
This trial adopts an open-label design combined with randomized, blinded, placebo-controlled and active-controlled design. The purpose of this trial is to evaluate the safety and immunogenicity of a Group ACYW135X Meningococcal Conjugate Vaccine. This study is planned to enroll 150 participants in total, with healthy individuals aged 2 to 59 years as participants. Among them, participants aged 18 to 59 years and 7 to 17 years will be assigned to the open-label design arm, while participants aged 4 to 6 years will be assigned to the randomized, blinded, placebo-controlled design arms.
125 studies on the registry are indexed under Meningitis, Meningococcal; 10 are open to participants now.
This study's planned enrollment of 150 is below the median of 538 across 113 interventional studies indexed under Meningitis, Meningococcal.
Browse Meningitis, Meningococcal studies →Sinovac Life Sciences Co., Ltd. is the lead sponsor of 26 studies on the registry; 11 are open to participants now.
Counted across the registry records on this site, refreshed daily.
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:
abnormal findings in laboratory tests：
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.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
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.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
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.
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
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.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
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.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
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.
Live vaccines
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Bilirubin
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
2\~59 years old
Biological: high-dose Group ACYW135X Meningococcal Conjugate Vaccine
2\~59 years old
Biological: medium-dose Group ACYW135X Meningococcal Conjugate Vaccine
2\~6 years old
Biological: low-dose Group ACYW135X Meningococcal Conjugate Vaccine
2\~6 years old
Biological: Placebo
2\~3 years old
Biological: Group ACYW135 Meningococcal Conjugate Vaccine (CRM197)
high-dose Group ACYW135X Meningococcal Conjugate Vaccine
medium-dose Group ACYW135X Meningococcal Conjugate Vaccine
low-dose Group ACYW135X Meningococcal Conjugate Vaccine
Group ACYW135 Meningococcal Conjugate Vaccine (CRM197)
Also known as: Menhycia
placebo
Evaluate the safety of experimental vaccine among participants in different age groups (based on adverse reactions)
The incidence rates of adverse reactions 30 days after vaccination
Time frame: 30 days
Evaluate the safety of experimental vaccine among participants in different age groups (based on AE and laboratory abnormalities)
The incidence rate of adverse events 30 days after vaccination
Time frame: 30 days
Evaluate the safety of experimental vaccine among participants in different age groups (based on AE and laboratory abnormalities)
The incidence rate of clinically significant abnormal blood biochemistry, blood routine, and urine routine indexes within 3 days after vaccination
Time frame: 3 days
Evaluate the safety of experimental vaccine among participants in different age groups (based on AE and laboratory abnormalities)
The incidence rate of serious adverse events 6 months after vaccination
Time frame: 6 months
Evaluate the immunogenicity of experimental vaccine among participants aged 2~6 years old
The seropositive rates, seroconversion rate, GMT and GMFR of Nm antibody against serogroups A, C, Y, W135, and X at 30 days after vaccination
Time frame: 30 days
Evaluate the immunogenicity of experimental vaccine among participants aged 2~6 years old
The proportion of Nm antibody against serogroups A, C, Y, W135, and X with titer ≥ 1:16, ≥ 1:32, ≥ 1:64, and ≥ 1:128 at 30 days after vaccination
Time frame: 30 days
No study locations are listed for this record.
This study is not yet recruiting, as verified in Jan 2026. You cannot join it, but the record below documents what was studied.
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