Boosting with Subtype C CN54rgp140 Protein Adjuvanted with Glucopyranosyl Lipid Adjuvant after Priming with HIV-DNA and HIV-MVA Is Safe and Enhances Immune Responses: A Phase I Trial

• Published in: PloS one 2016-05, Vol.11 (5), p.e0155702
• Main Authors: Joachim, Agricola, Bauer, Asli, Joseph, Sarah, Geldmacher, Christof, Munseri, Patricia J, Aboud, Said, Missanga, Marco, Mann, Philipp, Wahren, Britta, Ferrari, Guido, Polonis, Victoria R, Robb, Merlin L, Weber, Jonathan, Tatoud, Roger, Maboko, Leonard, Hoelscher, Michael, Lyamuya, Eligius F, Biberfeld, Gunnel, Sandström, Eric, Kroidl, Arne, Bakari, Muhammad, Nilsson, Charlotta, McCormack, Sheena
• Format: Article
• Language: English
• Subjects: Acquired immune deficiency syndrome; Adjuvants, Immunologic; Adolescent; Adult; AIDS; AIDS vaccines; AIDS Vaccines - adverse effects; AIDS Vaccines - genetics; AIDS Vaccines - immunology; Antibodies; Antibodies, Neutralizing - immunology; Antibody response; Antibody-Dependent Cell Cytotoxicity; Assaying; Binding; Biology and Life Sciences; C protein; Clinical trials; Cytotoxicity; Deoxyribonucleic acid; DNA; Drug delivery systems; env Gene Products, Human Immunodeficiency Virus - immunology; Enzyme-linked immunosorbent assay; Female; Gag protein; Genetic aspects; Glucosides; Health aspects; Healthy Volunteers; HIV; HIV Antibodies - immunology; HIV infections; HIV Infections - immunology; HIV Infections - prevention & control; HIV-1 - genetics; HIV-1 - immunology; Human immunodeficiency virus; Humans; Hypoglycemia; Immune response; Immune response (cell-mediated); Immunization; Immunization Schedule; Immunization, Secondary; Immunoglobulin G - immunology; Interferon-gamma - blood; Lentivirus; Lipid A; Lymphocyte Activation; Lymphocytes T; Male; Medical research; Medicin och hälsovetenskap; Medicine and Health Sciences; Neutralization; Neutralization Tests; Peptides; Peripheral blood; Physiological aspects; Prevention; Priming; Product development; Research and Analysis Methods; Tanzania; Toxicity; Vaccination; Vaccines; Vaccines, DNA - adverse effects; Vaccines, DNA - immunology; Vaccinia virus; Viral envelope proteins; Viral Vaccines; Viruses; Young Adult; γ-Interferon
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0155702

A vaccine against HIV is widely considered the most effective and sustainable way of reducing new infections. We evaluated the safety and impact of boosting with subtype C CN54rgp140 envelope protein adjuvanted in glucopyranosyl lipid adjuvant (GLA-AF) in Tanzanian volunteers previously given three immunizations with HIV-DNA followed by two immunizations with recombinant modified vaccinia virus Ankara (HIV-MVA). Forty volunteers (35 vaccinees and five placebo recipients) were given two CN54rgp140/GLA-AF immunizations 30-71 weeks after the last HIV-MVA vaccination. These immunizations were delivered intramuscularly four weeks apart. The vaccine was safe and well tolerated except for one episode of asymptomatic hypoglycaemia that was classified as severe adverse event. Two weeks after the second HIV-MVA vaccination 34 (97%) of the 35 previously vaccinated developed Env-specific binding antibodies, and 79% and 84% displayed IFN-γ ELISpot responses to Gag and Env, respectively. Binding antibodies to subtype C Env (included in HIV-DNA and protein boost), subtype B Env (included only in HIV-DNA) and CRF01_AE Env (included only in HIV-MVA) were significantly boosted by the CN54rgp140/GLA-AF immunizations. Functional antibodies detected using an infectious molecular clone virus/peripheral blood mononuclear cell neutralization assay, a pseudovirus/TZM-bl neutralization assay or by assays for antibody-dependent cellular cytotoxicity (ADCC) were not significantly boosted. In contrast, T-cell proliferative responses to subtype B MN antigen and IFN-γ ELISpot responses to Env peptides were significantly enhanced. Four volunteers not primed with HIV-DNA and HIV-MVA before the CN54rgp140/GLA-AF immunizations mounted an antibody response, while cell-mediated responses were rare. After the two Env subtype C protein immunizations, a trend towards higher median subtype C Env binding antibody titers was found in vaccinees who had received HIV-DNA and HIV-MVA prior to the two Env protein immunizations as compared to unprimed vaccinees (p = 0.07). We report excellent tolerability, enhanced binding antibody responses and Env-specific cell-mediated immune responses but no ADCC antibody increase after two immunizations with a subtype C rgp140 protein adjuvanted in GLA-AF in healthy volunteers previously immunized with HIV-DNA and HIV-MVA. International Clinical Trials Registry PACTR2010050002122368.