A Study of Dengue Vaccine in Healthy Toddlers Aged 12 to 15 Months in the Philippines

Immunogenicity and Safety of CYD Dengue Vaccine in Healthy Toddlers Aged 12 to 15 Months in the Philippines

The purpose of this study is to investigate the potential for co-administration of the first dose of CYD Dengue vaccine with childhood vaccination.

Primary Objectives:

• To describe the safety of CYD Dengue vaccine after each dose; first dose given alone or coadministered with childhood vaccines.

Secondary Objectives:

• To describe the immunogenicity of CYD Dengue vaccine after each dose; first dose given alone or co-administered with childhood vaccines.

Participants will be enrolled in a 3-step enrollment and randomized to 1 of 4 treatment groups. Groups 1 and 2 will receive 5 vaccinations, and Groups 3 and 4 will received 6 vaccinations (childhood vaccines or placebo co-administered with the first dose of CYD Dengue vaccine in 2 separate arms). All toddlers will receive a pentavalent acellular pertussis combination vaccine or Combo (PENTAXIM®), planned approximately 10 months after enrollment.

Inclusion Criteria :

• Toddler in good health based on medical history and medical examination
• Toddler aged 12 to 15 months on the day of inclusion
• Born at full term of pregnancy (≥ 37 weeks) and with a birth weight ≥ 2.5 kg
• Provision of informed consent form signed by the parent(s) or other legally acceptable representative (and by an independent witness if required by local regulations)
• Participant and parent/delegate able to attend all scheduled visits and comply with all trial procedures
• Completion of previous vaccination program according to the national immunization schedule, except for measles

Exclusion Criteria :

• Family members from the Investigator or from the staff involved in the trial
• Chronic illness that, in the opinion of the investigator, is at a stage where it might interfere with trial conduct or completion
• 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 corticosteroids therapy (prednisone or equivalent for more than 2 consecutive weeks within the past 3 months)
• History of central nervous system disorder or disease, including seizures
• History of varicella, measles, mumps, rubella and hepatitis A; confirmed either clinically, serologically, or microbiologically
• Thrombocytopenia, bleeding disorder or anticoagulants in the 3 weeks preceding inclusion
• Previous vaccination against measles-mumps-rubella, hepatitis A or varicella
• Previous vaccination against flavivirus diseases
• Known systemic hypersensitivity to any of the components of the vaccines, or history of a life-threatening reaction to the vaccines used in the trial or to a vaccine containing any of the same substances
• Planned participation in another clinical trial during the present trial period
• Participation in another clinical trial investigating a vaccine, drug, medical device, or medical procedure in the 4 weeks preceding the first trial vaccination
• Receipt of blood or blood-derived products in the past 3 months, which might interfere with assessment of the immune response
• Planned receipt of any vaccine in the 4 weeks following the first trial vaccination
• Human immunodeficiency virus (HIV) seropositivity in the blood sample taken at screening
• Clinically significant laboratory abnormalities, as judged by the Investigator, in blood sample taken at screening

Temporary exclusions: vaccination postponed until the condition is resolved:

• Febrile illness (temperature ≥ 38°C) or moderate or severe acute illness/infection on the day of vaccination, according to Investigator judgment
• Receipt of oral or injected antibiotic therapy within 72 hours prior to the vaccination visit
• Any vaccination received in the 4 weeks preceding vaccination