Excellent safety and tolerability of the human immunodeficiency virus type 1 pGA2/JS2 plasmid DNA priming vector vaccine in HIV type 1 uninfected adults

AIDS Res Hum Retroviruses. 2006 Jul;22(7):678-83. doi: 10.1089/aid.2006.22.678.


A vaccine consisting of DNA priming followed by recombinant modified vaccinia Ankara (rMVA) boosting has achieved long-term control of a pathogenic challenge with a chimera of simian and human immunodeficiency viruses (SHIV-89.6P) in rhesus macaques. Based on these results, clade B HIV-1 DNA and rMVA immunogens have been developed for trials in humans. We conducted a first-time in humans phase I safety trial using the pGA2/JS2 (JS2) HIV-1 DNA priming vector expressing Gag, Pol, Env, Tat, Rev, and Vpu. Thirty HIV-uninfected adults were vaccinated with 0.3 or 3 mg of JS2 DNA, or a saline placebo, by intramuscular injection at months 0 and 2. Both doses of DNA were safe and well-tolerated with no differences between the control, 0.3 mg, or 3 mg groups (n = 6, 12, and 12, respectively) through 12 months of postvaccination follow- up. A chromium-release assay using fresh peripheral blood mononuclear cells (PBMCs) and a validated IFN-gamma ELISpot assay with frozen PBMCs failed to detect CD4(+) or CD8(+) HIV-1-specific T cell responses. HIV-specific neutralizing antibodies were also not detected. The vaccine is being further developed as a priming vector for a combined DNA plus rMVA prime/boost HIV vaccination regimen.

Publication types

  • Clinical Trial, Phase I
  • Multicenter Study
  • Randomized Controlled Trial

MeSH terms

  • AIDS Vaccines / adverse effects*
  • AIDS Vaccines / immunology
  • Adult
  • Double-Blind Method
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Genetic Vectors / adverse effects
  • Genetic Vectors / immunology
  • HIV Antibodies / metabolism
  • HIV-1 / immunology*
  • Humans
  • Interferon-gamma / metabolism
  • Male
  • Plasmids / adverse effects*
  • Plasmids / immunology
  • Statistics, Nonparametric
  • T-Lymphocytes, Cytotoxic / immunology
  • Vaccines, DNA / adverse effects*
  • Vaccines, DNA / immunology
  • Vaccinia virus / genetics
  • Vaccinia virus / immunology*


  • AIDS Vaccines
  • HIV Antibodies
  • Vaccines, DNA
  • Interferon-gamma