Study of a Novel Tetravalent Dengue Vaccine in Healthy Children and Adolescents Aged 9 to 16 Years in Latin America

• Information on the occurrence of serious adverse events (SAEs), including SAEs of special interest in all subjects throughout the trial period [ Time Frame: Day 0 up to 12 months post vaccination ] [ Designated as safety issue: No ]
• Information on the efficacy of CYD dengue vaccine in preventing symptomatic dengue cases either virologically confirmed or probable based on serological criteria due to any of the four serotypes after each dose. [ Time Frame: 28 Days after each vaccination ] [ Designated as safety issue: No ]

The aim of the study is to assess the efficacy of sanofi pasteur's CYD dengue vaccine in preventing symptomatic virologically-confirmed dengue cases for dengue-endemic areas of Latin America.

Primary Objective:

To assess the efficacy of CYD dengue vaccine after 3 vaccinations at 0, 6, and 12 months in preventing symptomatic virologically-confirmed dengue cases, regardless of the severity, due to any of the four serotypes in children and adolescents aged 9 to 16 years at the time of inclusion.

Secondary Objectives:

To describe the occurrence of serious adverse events (SAEs), including SAEs of special interest in all subjects throughout the trial period.

To describe the efficacy of CYD dengue vaccine after each dose in:

• Preventing symptomatic virologically-confirmed dengue cases due to any of the four serotypes
• Preventing symptomatic dengue cases, either virologically-confirmed or probable based on serological criteria, due to any of the four serotypes

Participants will be randomized to either receive a total of 3 injections of CYD dengue vaccine or a placebo at 0, 6, and 12 months, respectively.

A subset of participants from each country will also be evaluated for reactogenicity and immunogenicity to enable the generation of country-specific data on reactogenicity, immunogenicity, and baseline dengue and yellow fewer antibody levels.

• Dengue Fever
• Dengue Hemorrhagic Fever
• Dengue

• Biological: Live, attenuated, dengue serotype 1, 2, 3, 4 virus
  0.5 mL, Subcutaneous
  Other Name: CYD Dengue Vaccine
• Biological: Placebo: NaCl 0.9% solution
  0.5 mL, Subcutaneous

• Experimental: CYD Dengue Vaccine Group
  Participants will receive a dose of CYD dengue vaccine at 0, 6, and 12 months, respectively.
  Intervention: Biological: Live, attenuated, dengue serotype 1, 2, 3, 4 virus
• Placebo Comparator: Control Group
  Participants will receive a dose of placebo vaccine at 0, 6, and 12 months, respectively.
  Intervention: Biological: Placebo: NaCl 0.9% solution

Inclusion Criteria:

• Aged 9 to 16 years on the day of inclusion and resident of the site zone
• Subject in good health, based on medical history and physical examination
• Assent form or informed consent form has been signed and dated by the subject (based on local regulations), and informed consent form has been signed and dated by the parent(s) or another legally acceptable representative (and by an independent witness if required by local regulations)
• Subject able to attend all scheduled visits and to comply with all trial procedures.

Exclusion Criteria:

• Subject is pregnant, or lactating, or of childbearing potential (to be considered of non-childbearing potential, a female must be pre-menarche for at least 1 year, surgically sterile, or using an effective method of contraception or abstinence from at least 4 weeks prior to the first vaccination until at least 4 weeks after the last vaccination).
• Participation in another clinical trial investigating a vaccine, drug, medical device, or a medical procedure in the 4 weeks preceding the first trial vaccination
• Planned participation in another clinical trial during the present trial period
• Self-reported 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)
• Self-reported seropositivity for Human Immunodeficiency Virus (HIV) infection
• Self-reported systemic hypersensitivity to any of the vaccine components, or history of a life-threatening reaction to the vaccine used in the trial or to a vaccine containing any of the same substances
• Chronic illness that, in the opinion of the Investigator, is at a stage where it might interfere with trial conduct or completion
• 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 any trial vaccination
• Deprived of freedom by administrative or court order, or in an emergency setting, or hospitalized involuntarily
• Current alcohol abuse or drug addiction that may interfere with the subject's ability to comply with trial procedures
• Identified as a site employee of the Investigator or study center, with direct involvement in the proposed study or other studies under the direction of that Investigator or study center, as well as a family member (i.e., immediate, husband, wife and their children, adopted or natural) of the site employees or the Investigator.