Long-Term Study of Hospitalized Dengue & Safety in Thai Children Included in a Tetravalent Dengue Vaccine Efficacy Study

Long-Term Follow-Up of Hospitalized Dengue and Safety in Thai Children Who Were Included in an Efficacy Study of a Tetravalent Dengue Vaccine

The purpose of this study was to conduct a passive surveillance of hospitalized dengue cases in participants who participated in study CYD23 (NCT00842530).

The Objectives:

• To describe the incidence of virologically-confirmed hospitalized dengue cases.
• To characterize hospitalized dengue cases.
• To evaluate the occurrence of related and fatal serious adverse events (SAEs).

This study was a passive surveillance of hospitalized dengue cases in participants who participated in study CYD23 (NCT00842530) where participants were initially randomized to receive 3 injections of either CYD dengue vaccine or control at 6 month intervals. Any SAE related to a study procedure or related to a previous injection from study CYD23, or any fatal SAEs (even if unrelated) were reported to the Sponsor.

An Independent Data Monitoring Committee (IDMC) was also involved in the regular review of virologically-confirmed hospitalized dengue cases. Any fatal outcome or related SAE were be promptly reviewed by the IDMC.

No study vaccinations were administered.

Inclusion Criteria:

• Ongoing participation in study CYD23 at the time of enrolment.
• Assent form was signed and dated by the participant (for participants >= 7 years old), and informed consent form was signed and dated by the parent(s) or another legally accepted representative and by 2 independent witnesses.
• Participant and parent/legally accepted representative were able to attend all scheduled visits to comply with all study procedures.

Exclusion Criteria:

• Planned participation in another dengue clinical trial during the present study
• Deprived of freedom by an administrative or court order, or in an emergency setting, or hospitalized involuntarily.