Robust antibody and cellular responses induced by DNA-only vaccination for HIV.

DeRosa, Stephen; Edupuganti, Srilatha; Huang, Yunda; Han, Xue; Elizaga, Marnie; Swann, Edith; Polakowski, Laura; Kalams, Spyros A; Keefer, Michael C; Maenza, Janine; Lu, Yiwen; Wise, Megan C; Yan, Jian; Morrow, Matthew P; Khan, Amir S; Boyer, Jean; Humeau, Laurent M; White, Scott; Pensiero, Michael N; Sardesai, Niranjan Y; Bagarazzi, Mark; Weiner, David B; Ferrari, Guido; Tomaras, Georgia; Montefiori, David; Corey, Lawrence; McElrath, M Juliana

BACKGROUND HVTN 098, a randomized, double-blind, placebo-controlled trial, evaluated the safety, tolerability and immunogenicity of PENNVAX®-GP HIV DNA vaccine, administered with or without plasmid IL-12 (pIL-12), via intradermal (ID) or intramuscular (IM) electroporation (EP) in healthy, HIV-uninfected adults. The study tested whether PENNVAX®-GP delivered via ID/EP at 1/5th the dose could elicit equivalent immune responses to delivery via IM/EP, and if inclusion of pIL-12 provided additional benefit. METHODS Participants received DNA encoding HIV-1 env/gag/pol in three groups: 1.6mg ID (ID no IL-12 group, n=20), 1.6mg ID + 0.4mg pIL-12 (ID+IL-12 group, n=30), 8mg IM + 1mg pIL-12 (IM+IL-12 group, n=30) or placebo (n=9) via EP at 0, 1, 3 and 6 months. Results of cellular and humoral immunogencity assessments are reported. RESULTS Following vaccination, the frequency of responders (response rate) to any HIV protein based on CD4+ T-cells expressing IFN-γ and/or IL-2 was 96% for both the ID+IL-12 and IM+IL-12 groups; CD8+ T-cell response rates were 64% and 44%, respectively. For ID delivery, the inclusion of pIL-12 increased CD4+ T-cell response rate from 56% to 96%. The frequency of responders was similar (>90%) for IgG binding Ab to gp140 consensus Env across all groups, but the magnitude was higher in the ID+IL-12 group compared to the IM+IL-12 group. CONCLUSION PENNVAX®-GP DNA induced robust cellular and humoral immune responses, demonstrating that immunogenicity of DNA vaccines can be enhanced by EP route and inclusion of pIL-12. ID/EP was dose-sparing, inducing equivalent, or in some aspects superior, immune responses compared to IM/EP. TRIAL REGISTRATION ClinicalTrials.gov NCT02431767Funding: This work was supported by the National Institute of Allergy and Infectious Diseases (NIAID, https://www.niaid.nih.gov/) U.S. Public Health Service Grants UM1 AI068618 [LC: HIV 75 Vaccine Trials Network], UM1 AI068614 [LOC: HIV Vaccine Trials Network], UM1 AI068635 76 [SDMC: HIV Vaccine Trials Network], , U01 AI069418-ˇ08 [Emory-ˇCDC Clinical Trials Unit], UM AI069511 [University of Rochester HIV/AIDS Clinical Trials Unit], UM1 AI069439 77 [Vanderbilt Clinical Trial Unit], UM1 AI069481 [Seattle-ˇLausanne Clinical Trials Unit] and HVDDT Contract HHSN2722008000063C (Inovio Pharmaceuticals). This work was also supported, in part, by IPCAVD award U19 AI09646-ˇ03 (DBW) and NIH award P01 AI120756 (GDT). The opinions expressed in this article are those of the authors and do not necessarily represent the official views of the NIAID or the National Institutes of Health (NIH).