Table 2.

Main immunogenicity findings of Phase I/II trials

No broadly neutralizing antibodies are induced by current vaccines.

Binding antibodies and neutralizing antibodies against Tier-1 and limited Tier-2 HIV-1 isolates were induced by Env subunit proteins formulated with potent adjuvants.

Polyfunctional CD4+ and CD8+ T-cell responses measured by ICS and INF-γ ELISpot assays generally of low to moderate magnitude immune responses have been detected in a majority of vaccinees immunized by vectors alone and to some extent by DNA alone. These responses are generally significantly augmented after priming.

CD8-mediated inhibition of in vitro viral replication can be detected after vector-based vaccination.

Cell-mediated responses to DNA administered by electroporation are significantly augmented compared to intramuscular needle injection

Systems biology can identify specific gene activation immune signatures predictive of the immune responses

Pre-existing immunity to pox vectors does not or minimally impact on the pox vector vaccine-induced immune responses, in particular after DNA prime

Pre-existing immunity to Ad5 (high prevalence) decreases the Ad5 vaccine-induced immune responses, which led to the development of low prevalence rare serotype adenovirus vectors.

Env subunit protein boosts induce higher levels of serum antibodies that rapidly wane.