PLoS ONE (Jan 2015)

A Phase I Double Blind, Placebo-Controlled, Randomized Study of the Safety and Immunogenicity of Electroporated HIV DNA with or without Interleukin 12 in Prime-Boost Combinations with an Ad35 HIV Vaccine in Healthy HIV-Seronegative African Adults.

  • Juliet Mpendo,
  • Gaudensia Mutua,
  • Julien Nyombayire,
  • Rosine Ingabire,
  • Annet Nanvubya,
  • Omu Anzala,
  • Etienne Karita,
  • Peter Hayes,
  • Jakub Kopycinski,
  • Len Dally,
  • Drew Hannaman,
  • Michael A Egan,
  • John H Eldridge,
  • Kristen Syvertsen,
  • Jennifer Lehrman,
  • Beth Rasmussen,
  • Jill Gilmour,
  • Josephine H Cox,
  • Patricia E Fast,
  • Claudia Schmidt

DOI
https://doi.org/10.1371/journal.pone.0134287
Journal volume & issue
Vol. 10, no. 8
p. e0134287

Abstract

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Strategies to enhance the immunogenicity of DNA vaccines in humans include i) co-administration of molecular adjuvants, ii) intramuscular administration followed by in vivo electroporation (IM/EP) and/or iii) boosting with a different vaccine. Combining these strategies provided protection of macaques challenged with SIV; this clinical trial was designed to mimic the vaccine regimen in the SIV study.Seventy five healthy, HIV-seronegative adults were enrolled into a phase 1, randomized, double-blind, placebo-controlled trial. Multi-antigenic HIV (HIVMAG) plasmid DNA (pDNA) vaccine alone or co-administered with pDNA encoding human Interleukin 12 (IL-12) (GENEVAX IL-12) given by IM/EP using the TriGrid Delivery System was tested in different prime-boost regimens with recombinant Ad35 HIV vaccine given IM.All local reactions but one were mild or moderate. Systemic reactions and unsolicited adverse events including laboratory abnormalities did not differ between vaccine and placebo recipients. No serious adverse events (SAEs) were reported. T cell and antibody response rates after HIVMAG (x3) prime-Ad35 (x1) boost were independent of IL-12, while the magnitude of interferon gamma (IFN-γ) ELISPOT responses was highest after HIVMAG (x3) without IL-12. The quality and phenotype of T cell responses shown by intracellular cytokine staining (ICS) were similar between groups. Inhibition of HIV replication by autologous T cells was demonstrated after HIVMAG (x3) prime and was boosted after Ad35. HIV specific antibodies were detected only after Ad35 boost, although there was a priming effect with 3 doses of HIVMAG with or without IL-12. No anti-IL-12 antibodies were detected.The vaccines were safe, well tolerated and moderately immunogenic. Repeated administration IM/EP was well accepted. An adjuvant effect of co-administered plasmid IL-12 was not detected.ClinicalTrials.gov NCT01496989.