A novel prophylactic AIDS vaccine candidate, consisting of single-stranded DNA for HIV-1 subtype C gag, protease, and part of reverse transcriptase genes, enclosed within a recombinant adeno-associated virus serotype-2 protein capsid (tgAAC09) induced T cell responses and antibodies in nonhuman primates. In this randomized, dose escalation phase I trial, HIV-uninfected healthy volunteers (50 in Europe, 30 in India) received a single intramuscular injection of tgAAC09 at 3 × 109 DNase resistant particles (DRP) (n = 16), 3 × 1010 DRP (n = 23), 3 × 1011 DRP (n = 25), or placebo (n = 16). Twenty-one participants in Europe received a second (boost) dose of 3 × 1011 DRP tgAAC09 or placebo at least 24 weeks after the first injection. The vaccine was safe and well-tolerated after initial and boost vaccination. Local and systemic reactogenicity was experienced by 13–25% of participants and was not dose related. No vaccine-related serious adverse events were reported. Modest HIV-specific T cell responses were detected in 7/64 vaccinees (40–385 SFC/106 PBMC), with 16% (4/25) responders in the highest dose group. All responses were to Gag epitopes. tgAAC09 appears to be safe, well-tolerated, and modestly immunogenic. Further evaluation of higher doses of tgAAC09 and boost injections is ongoing in Africa.
AIDS Research and Human Retroviruses (2008) 24 (6) 873-880 [doi:10.1089/aid.2007.0292]