The purpose of the study was to evaluate the immunogenicity and safety profile of a single dose of Meningococcal Polysaccharide (Serogroups A, C, Y, and W) Tetanus Toxoid (MenACYW) Conjugate vaccine when given alone compared to that of the licensed Meningococcal groups A, C, W 135 and Y (NIMENRIX®) Conjugate vaccine.

Observational objectives:

• To evaluate the antibody responses to the antigens (serogroups A, C, Y, and W) present in MenACYW Conjugate vaccine and NIMENRIX® measured by serum bactericidal assay using baby rabbit complement (rSBA) and by serum bactericidal assay using human complement (hSBA)
• To evaluate the antibody responses against tetanus in participants who received MenACYW Conjugate vaccine or NIMENRIX® vaccine
• To evaluate the safety profile of MenACYW Conjugate vaccine and NIMENRIX®

All participants received 1 dose of MenACYW Conjugate vaccine or NIMENRIX® on Day 0 and were evaluated for immunogenicity and safety profile. The duration of each participant's participation in the trial was 30 to 44 days.

Inclusion Criteria:

• Aged 12 to 23 months on the day of the first study visit.
• Born at full term of pregnancy (greater than or equal to [≥] 37 weeks) or with a birth weight ≥2.5 kilogram (kg) (5.5 pounds).
• Inform Consent Form (ICF) had been signed and dated by the parent(s) or other legally acceptable representative (and by an independent witness if required by local regulations).
• Participant and parent/legally acceptable representative were able to attend all scheduled visits and to comply with all trial procedures.
• Covered by health insurance where applicable.

Exclusion Criteria:

• 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.
• Receipt of any vaccine in the 4 weeks preceding the trial vaccination or planned receipt of any vaccine before the final blood draw except for influenza vaccination, which might be received at least 2 weeks before or after the study vaccine.
• Previous vaccination against meningococcal disease with either the trial vaccine or mono-, or polyvalent polysaccharide or Conjugate meningococcal vaccine containing serogroups A, B, C, W, or Y.
• Receipt of immune globulins, blood, or blood-derived products in the past 3 months.
• 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 (≥ 2 milligram [mg]/kg/day of 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 (i.e., participants with persistent complement deficiency, with anatomic or functional asplenia, or participants travelling to countries with high endemic or epidemic disease).
• 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.
• Known systemic hypersensitivity to latex.
• Known thrombocytopenia, as reported by the parent/legally acceptable representative.
• Bleeding disorder or receipt of anticoagulants in the 3 weeks preceding inclusion, contraindicating IM vaccination.
• Personal history of Guillain-Barré syndrome.
• Personal history of an Arthus-like reaction after vaccination with a tetanus toxoid-containing vaccine.
• Chronic illness that, in the opinion of the Investigator, was 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 degree Celsius (°C). A prospective participant should not be included in the study until the condition had resolved or the febrile event had subsided.
• Receipt of oral or injectable antibiotic therapy within 72 hours prior to the first blood draw.
• Identified as a natural or adopted child of the Investigator or employee with direct involvement in the proposed study.

Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants. Further details on Sanofi's data sharing criteria, eligible studies, and process for requesting access can be found at: https://vivli.org