Examining the Role of Genetics in Determining the Immune Response to an HIV Vaccine in HIV-Uninfected Adult Twins
Condition: HIV Infections
MeSH terms: HIV Infections
Study type: Interventional
Phase: Phase 1

Summary: 
      The purpose of this study is to examine the role of genetics in determining the immune
      response to an HIV vaccine in pairs of HIV-uninfected twins.
    

Detailed description: 
      Genetics may play a role in the immune response to HIV vaccines. It remains unknown, however,
      exactly what the genetic influence on the immune response may be. This study will examine how
      genes affect the strength of an immune response produced by HIV vaccines and how genes
      influence different immune responses. In this study, participants will receive two HIV
      vaccines-a DNA HIV vaccine (VRC-HIVDNA016-00-VP) and a recombinant adenoviral serotype 5
      (rAd5) vector HIV vaccine (HIVADV014-00-VP). Both of these vaccines are experimental, but
      have been used in previous clinical trials without any serious side effects. Comparing
      immunological responses in HIV vaccine trials can be complicated by various genetic and
      environmental factors. This study will enroll pairs of twins who grew up in common childhood
      environments. This will provide researchers with participants who have similar backgrounds so
      that the role of genetics can be examined while controlling for other environmental
      variables. The purpose of this study is to examine how genes may influence the immune
      response to a DNA HIV vaccine followed by a rAd5 HIV vaccine.

      This study will enroll pairs of healthy, HIV-uninfected monozygotic and dizygotic adult
      twins. Participants will receive the DNA vaccine at baseline and Months 1 and 2, and the rAd5
      vaccine at Month 6. Both vaccines will be injected into the upper arm. At all vaccination
      study visits, participants will undergo a medical history and medication history review,
      physical exam, and blood collection. Participants will also complete questionnaires and a
      social impact assessment. They will receive counseling on HIV testing, risk reduction, and
      pregnancy prevention. After receiving the vaccine, participants will remain in the clinic for
      at least 30 minutes for observation and monitoring of side effects. For 3 days after each
      vaccination, participants will record their temperature and side effects in a symptom log. In
      addition to the vaccine study visits, additional study visits will occur at Weeks 2, 6, and
      10; 1, 3, and 7 days after the Month 6 visit; and Months 7, 9, 12, and 18. Various study
      procedures, including a physical exam, blood collection, and counseling, will be repeated at
      these visits. At the end of 18 months, participants will be contacted by study researchers
      once a year for 3 ½ years for follow-up health monitoring.
    

Intervention name(s): HIV-1 DNA plasmid vaccine; HIV-1 recombinant Ad5 vaccine
Intervention type(s): Biological; Biological
Intervention description(s): 4 mg injection administered as 1 mL intramuscularly via Biojector in deltoid; 1 x 10^10 particle units (PU) administered as 1 mL intramuscularly by needle and syringe in deltoid
Other intervention name(s): VRC-HIVDNA016-00-VP; VRC-HIVADV014-00-VP
Intervention MeSH terms: Vaccines
Allocation: Non-Randomized
Intervention model: Single Group Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Prevention
Keywords: HIV Seronegativity; HIV Preventive Vaccine