NCT04936685 - Study on an Investigational Quadrivalent Meningococcal Conjugate Vaccine (MenACYW Conjugate Vaccine) Administered as a 5- and/or 10-year Booster Doses in Children and Adolescents Vaccinated 5 or 10 Years Earlier as Toddlers | Crick

Eligibility

Sex: ALLMin age: 6 YearsMax age: 7 YearsHealthy volunteers:

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Inclusion Criteria: * Received MenACYW vaccine in MET51 study (Groups 1 and 3) and completed the study (attended Visit 2) * Participant and parent/ legally acceptable representative (LAR) are able to attend all scheduled visits and to comply with all trial procedures * Covered by health insurance, if required by local regulations Exclusion Criteria: * Known or suspected congenital or acquired immunodeficiency; or receipt of immunosuppressive therapy, such as anti-cancer chemotherapy or radiation therapy, within the preceding 6 months; or long-term systemic corticosteroid therapy (prednisone or equivalent for more than 2 consecutive weeks within the past 3 months) * History of meningococcal infection, confirmed either clinically, serologically, or microbiologically * At high risk for meningococcal infection during the trial (specifically but not limited to participants with persistent complement deficiency, with anatomic or functional asplenia, or participants traveling to countries with high endemic or epidemic disease) * Personal history of Guillain-Barré syndrome (GBS) * Personal history of an Arthus-like reaction after vaccination with a tetanus toxoid containing vaccine * Known systemic hypersensitivity to any of the vaccine components, or history of a life-threatening reaction to the vaccines used in the trial or to a vaccine containing any of the same substances * Verbal report by parent or LAR of thrombocytopenia or suspected thrombocytopenia, contraindicating intramuscular (IM) vaccination * Bleeding disorder, or receipt of anticoagulants in the 3 weeks preceding inclusion, contraindicating IM vaccination * Previous vaccination against meningococcal disease with either the trial vaccine or another vaccine (ie, mono- or polyvalent, polysaccharide, or conjugate meningococcal vaccine containing serogroups A, C, W, or Y) with the exception of licensed MenC vaccination received during infancy (MET51 Group 3), of the single dose of meningococcal vaccine administered as part of study MET51 (Group 1 and 3) and of Meningococcal B vaccine * Receipt of any vaccine in the 4 weeks preceding the trial vaccination or planned receipt of any vaccine in the 4 weeks following trial vaccination except for influenza vaccination, which may be received at least 2 weeks before or after study vaccines. This exception includes monovalent pandemic influenza vaccines and multivalent influenza vaccines * Receipt of immune globulins, blood or blood-derived products in the past 3 months * Receipt of oral or injectable antibiotic therapy within 72 hours prior to the first blood draw * Participation at the time of study enrollment (or in the 4 weeks preceding the trial vaccination) or planned participation during the present trial period in another clinical trial investigating a vaccine, drug, medical device, or medical procedure * Chronic illness that, in the opinion of the Investigator, is at a stage where it might interfere with trial conduct or completion * Moderate or severe acute illness/infection (according to Investigator judgment) on the day of vaccination or febrile illness (temperature ≥ 38.0°C). A prospective participant should not be included in the study until the condition has resolved or the febrile event has subsided * Deprived of freedom by an administrative or court order, or in an emergency setting, or hospitalized involuntarily * Identified as a natural or adopted child of the Investigator or employee with direct involvement in the proposed study * The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.

Outcomes

Primary Outcomes

Group 1: Percentage of Participants With Sufficiency of Serum Bactericidal Assay Using Human Complement (hSBA) Vaccine Seroresponse at 30 Days Post Booster Dose

Functional meningococcal antibody activity against serogroups A, C, Y, and W were measured in a serum bactericidal assay utilizing the hSBA. hSBA vaccine seroresponse for serogroups A, C, W, and Y is defined as: percentage of participants with a pre-vaccination titer \< 1:8, who had achieved a post-vaccination titer \>= 1:16 or participants with a pre-vaccination titer \>= 1:8, who had achieved a post-vaccination titer at least 4-fold greater than the pre-vaccination titer. The seroresponse sufficiency was demonstrated if the lower limit of 1-sided 97.5% confidence interval (CI) is \> 75%.

Time frame: Baseline (Day 1) and 30 days after the MenACYW conjugate vaccine 5-year booster dose

Secondary Outcomes

Antibody Persistence of Meningococcal (Groups 1 and 2): Percentage of Participants Achieving Titer (Seroprotection) >=1:8 hSBA and Serum Bactericidal Assay Using Baby Rabbit Complement (rSBA) Titer >=1:8 Approximately 5 Years After the Primary Vaccination

Functional meningococcal antibody activity against serogroups A, C, Y, and W were measured in a serum bactericidal assay utilizing the hSBA and the rSBA and the results were expressed as vaccine seroprotection. Seroprotection rate is defined as percentage of participants with hSBA titer and rSBA titer \>=1.8 who received MenACYW conjugate vaccine 5 years earlier. Antibody persistence of meningococcal serogroups A, C, W, and Y in children at 5 years (Groups 1 and 2).

Time frame: At Day 1 (approximately 5 year after the administration of a priming dose as toddlers in study MET51)

Group 1: Geometric Mean Titers Against Meningococcal Serogroups A, C, W, and Y

Time frame: Baseline (Day 1) and Day 31 after the administration of a 5-year booster dose

Group 2: Geometric Mean Titers Against Meningococcal Serogroups A, C, W, and Y