Immunogenicity and Safety of an Investigational Quadrivalent Meningococcal Conjugate Vaccine in Healthy Toddlers

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.

• Meningococcal Polysaccharide (Serogroups A, C, Y, and W) Tetanus Toxoid Conjugate Vaccine (Biological), also known as MenACYW Conjugate vaccine: 0.5 milliliter (mL), Intramuscular (IM)
• Meningococcal Polysaccharide groups A, C, W-135 and Y Conjugate Vaccine (Biological), also known as NIMENRIX®: 0.5 mL, IM

Primary outcomes

• Number of Participants Reporting Solicited Injection-Site and Systemic Reaction Following Vaccination With Either MenACYW Conjugate Vaccine or NIMENRIX® [Day 0 up to Day 7 post-vaccination]: A solicited reaction was defined as an adverse reaction (AR) observed and reported under the conditions (symptom and onset) prelisted (i.e., solicited) in the case report form (CRF) and considered as related to vaccination. Solicited injection site reactions: Tenderness, Erythema, and Swelling. Solicited systemic reactions: Fever, Vomiting, Crying abnormal, Drowsiness, Appetite lost, and Irritability. Grade 3 solicited injection site reactions: Tenderness: cries when injected limb was moved or the movement of the injected limb was reduced; Erythema and Swelling: greater than or equal to (≥) 50 millimeter (mm). Grade 3 solicited systemic reactions: Fever: greater than \[>\] 39.5 degree Celsius (°C); Vomiting: ≥6 episodes per 24 hours or requiring parenteral hydration; crying abnormal: >3 hours; Drowsiness: sleeping most of the time or difficult to wake up; Appetite lost: refuses ≥3 feeds or refuses most feeds; Irritability: inconsolable.

Sex: All, ages: 12 Months to 23 Months, accepts healthy volunteers

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.

Participant flow

Outcome results

• Number of Participants Reporting Solicited Injection-Site and Systemic Reaction Following Vaccination With Either MenACYW Conjugate Vaccine or NIMENRIX® (Primary), Count of participants, Participants: Group 1: MenACYW Conjugate Vaccine 28; Group 2: NIMENRIX® 31

Adverse events

Time frame: Unsolicited adverse events (AEs) data were collected from Day 0 up to Day 30 post-vaccination. The solicited reactions (SRs) were collected up to Day 7 after vaccination. Serious AEs were collected throughout the trial (up to 30 days after vaccination).

Serious adverse events by term

Other adverse events by term

• Results publication: Vesikari T, Borrow R, Forsten A, Findlow H, Dhingra MS, Jordanov E. Immunogenicity and safety of a quadrivalent meningococcal tetanus toxoid-conjugate vaccine (MenACYW-TT) in healthy toddlers: a Phase II randomized study. Hum Vaccin Immunother. 2020 Jun 2;16(6):1306-1312. doi: 10.1080/21645515.2020.1733869. Epub 2020 Apr 1. PMID 32233959

• Medical Director, Study director, Sanofi Pasteur Inc.

NIH grants: 2014