Safety of and Immune Response to Two Different Dengue Virus Vaccines in Individuals Previously Immunized Against Dengue Virus
Condition: Dengue Hemorrhagic Fever
MeSH terms: Dengue; Hemorrhagic Fevers, Viral; Severe Dengue
Study type: Interventional
Phase: Phase 1

Summary: 
      Dengue fever, which is caused by dengue viruses, is a major health problem in subtropical
      regions of the world. There are four different forms (serotypes) of dengue virus that can
      cause dengue fever. The purpose of this study is to determine the safety and immune response
      to a vaccine containing a particular dengue serotype when an individual has been previously
      vaccinated with a different dengue serotype.
    

Detailed description: 
      The World Health Organization estimates that dengue virus causes more than 50 million cases
      of dengue fever a year. Dengue virus infection is the leading cause of hospitalization and
      death in children of most tropical Asian countries. There are four different serotypes of
      dengue virus. Most cases of dengue hemorrhagic fever/dengue shock syndrome are caused by
      secondary infection with a dengue serotype different from the first serotype the individual
      was infected with. A vaccine that would be effective in preventing infection by multiple
      dengue serotypes is desirable. The purpose of this study is to determine the safety of and
      immune response to two different dengue virus vaccines in individuals who have been
      previously vaccinated against a different serotype.

      This study will last at least 42 days. Participants will be recruited from a database of
      previous dengue vaccine recipients and will be stratified by the type of vaccine previously
      received. Participants assigned to Cohort 1 and Cohort 2 will have already been vaccinated
      with the rDEN4delta30 vaccine. Participants assigned to Cohort 3 will have already been
      vaccinated with the rDEN2/4delta30(ME) vaccine. Participants in Cohort 4 will have already
      been vaccinated with the rDEN1delta30 vaccine. Participants in Cohorts 1 and 3 will be
      randomly assigned to receive either the rDEN1delta30 vaccine or placebo. Participants in
      Cohorts 2 and 4 will be randomly assigned to receive either the rDEN2/4delta30(ME) vaccine or
      placebo.

      Participants will receive their assigned vaccination on Day 0. Study visits will occur every
      other day until Day 16, and then at Days 21, 28, and 42. At each visit, blood collection,
      vital signs measurement, and a physical exam will occur. In addition, participants will be
      asked to monitor their temperature daily, 3 times a day, from Day 0 to Day 16. Patients will
      also be asked to enroll in an optional skin biopsy sub-study.
    

Intervention name(s): rDEN1delta30; rDEN2/4delta30(ME); Placebo to rDEN1delta30 or rDEN2/4delta30(ME)
Intervention type(s): Biological; Biological; Biological
Intervention description(s): Live attenuated 10^3 dose of rDEN1delta30 vaccine. Participants must have been previously vaccinated with rDEN4delta30 or rDEN2/4delta30(ME) vaccines.; Live attenuated 10^3 dose of rDEN2/4delta30(ME) vaccine. Participants must have been previously vaccinated with rDEN4delta30 or rDEN1delta30 vaccines.; Placebo vaccines for rDEN1delta30 and rDEN2/4delta30(ME)
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Primary purpose: Prevention
Keywords: Dengue Fever; Dengue Hemorrhagic Fever; Dengue Vaccination