Baden LR, et al. - Researchers have recognized mosaic immunogens as bioinformatically engineered HIV-1 sequences designed to elicit clade independent coverage against globally circulating HIV-1 strains. In the present study, they identified no safety concerns and noted elicitation of multi-clade HIV-1 specific immune responses.

Methods

• Researchers performed Phase 1 double-blind, randomized, placebo-controlled trial enrolling healthy HIV uninfected adults who received two doses of a modified vaccinia Ankara (MVA) vectored HIV-1 bivalent mosaic immunogen vaccine or placebo on days 0 and 84.
• They enrolled 2 groups: those who were HIV-1 vaccine naïve (N=15) and those who had received an HIV-1 vaccine four to six years earlier (Ad26.ENVA.01, N=10).
• Pre-specified blinded cellular and humoral immunogenicity analyses were performed at days 0, 14, 28, 84, 98, 112, 168, 270, and 365.

Results

• Researchers administered all 50 planned vaccinations.
• Vaccination was noted to be safe and was generally well tolerated.
• They noted no vaccine-related serious adverse events.
• In all participants in the HIV-1 vaccine naïve group, both cellular and humoral cross-clade immune responses were elicited after one or two vaccinations.
• After a single immunization, env-specific responses were induced in nearly all subjects who had previously received the prototype Ad26.ENVA.01 vaccine.