Immunogenicity and Safety of a Quadrivalent Meningococcal Conjugate Vaccine When Administered Concomitantly With Routine Pediatric Vaccines in Healthy Infants and Toddlers in the US

Healthy infants will be enrolled and randomized to receive either 4 doses of MenACYW
conjugate vaccine or 4 doses of the licensed control vaccine, MENVEO®. All participants will
receive routine vaccines as per the Advisory Committee on Immunization Practices (ACIP)
recommendations.

All participants will be assessed for immunogenicity at baseline (pre-vaccination), and after
completing the infant schedule and the second year of life vaccination schedule.

Safety will be assessed throughout the study period, and includes solicited injection site
and systemic reactions as well as unsolicited adverse events after each vaccine injection,
and serious adverse events occurring throughout the trial.

Inclusion Criteria:

- Aged ≥ 42 to ≤ 89 days on the day of the first study visit.

- Born at full term of pregnancy (≥ 37 weeks) and with a birth weight ≥ 2.5 kg

- Informed consent form has been signed and dated by the parent(s) or guardian, and an
independent witness, if required by local regulations

- Subject and parent/guardian are able to attend all scheduled visits and to comply with
all trial procedures.

- Infants who received the first dose of hepatitis B vaccine at least 28 days before the
first study visit

Exclusion Criteria:

- Participation at the time of study enrollment or in the 4 weeks preceding the first
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 first trial vaccination or planned
receipt of any vaccine in the 4 weeks before and/or following any trial vaccination
except for influenza vaccination, which may be received at a gap of at least 2 weeks
before or 2 weeks after any study vaccination. This exception includes monovalent
pandemic influenza vaccines and multivalent influenza vaccines

- Previous vaccination against meningococcal disease with either the trial vaccine or
another vaccine (i.e., mono- or polyvalent, PS, or conjugate meningococcal vaccine
containing serogroups A, C, Y, or W; or meningococcal B serogroup-containing vaccine).

- Previous vaccination against diphtheria, tetanus, pertussis, poliomyelitis, hepatitis
A, measles, mumps, rubella, varicella; and of Haemophilus influenzae type b,
Streptococcus pneumoniae, and /or rotavirus infection or disease

- Receipt of more than 1 previous dose of hepatitis B vaccine

- Receipt of immune globulins, blood, or blood-derived products since birth

- Known or suspected congenital or acquired immunodeficiency; or receipt of
immunosuppressive therapy, such as anti-cancer chemotherapy or radiation therapy; or
long-term systemic corticosteroid therapy (prednisone or equivalent for more than 2
consecutive weeks) since birth

- Family history of congenital or hereditary immunodeficiency, until the immune
competence of the potential vaccine recipient is demonstrated

- Individuals with blood dyscrasias, leukemia, lymphoma of any type, or other malignant
neoplasms affecting the bone marrow or lymphatic systems

- Individuals with active tuberculosis

- History of any Neisseria meningitidis infection, confirmed either clinically,
serologically, or microbiologically

- History of diphtheria, tetanus, pertussis, poliomyelitis, hepatitis B, hepatitis A,
measles, mumps, rubella, varicella; and of Haemophilus influenzae type b,
Streptococcus pneumoniae, and /or rotavirus infection or disease

- At high risk for meningococcal infection during the trial (specifically, but not
limited to, subjects with persistent complement deficiency, with anatomic or
functional asplenia, or subjects travelling to countries with high endemic or epidemic
disease)

- History of intussusception

- History of any neurologic disorders, including any seizures and progressive neurologic
disorders

- History of Guillain-Barré syndrome

- Known systemic hypersensitivity to any of the vaccine components or to latex, or
history of a life-threatening reaction to the vaccine(s) used in the trial or to a
vaccine containing any of the same substances, including neomycin, gelatin, and yeast

- Verbal report of thrombocytopenia contraindicating intramuscular vaccination in the
investigator's opinion

- Bleeding disorder, or receipt of anticoagulants in the 3 weeks preceding inclusion,
contraindicating intramuscular vaccination in the investigator's opinion

- Receipt of oral or injectable antibiotic therapy within 72 hours prior to the first
blood draw

- Chronic illness that, in the opinion of the investigator, is at a stage where it might
interfere with trial conduct or completion

- Any condition which, in the opinion of the investigator, might interfere with the
evaluation of the study objectives

- Moderate or severe acute illness/infection (according to investigator judgment) on the
day of vaccination or febrile illness (temperature ≥ 38.0°C [≥ 100.4°F]). A
prospective subject should not be included in the study until the condition has
resolved or the febrile event has subsided

- Identified as a natural or adopted child of the investigator or employee with direct
involvement in the proposed study