Journal Article

The tuberculosis vaccine H4:IC31 is safe and induces a persistent polyfunctional CD4 T cell response in South African adults: A randomized controlled trial

Andersen, Peter, Hoff, Søren T., Miles, David J.C., Mahomed, Hassan, Scriba, Thomas J., Mearns, Helen, de Bruyn, Guy, Hokey, David, Bruce McClain, J., Tameris, Michele, Kromann, Ingrid, Ryall, Robert, Geldenhuys, Hennie, Hatherill, Mark, Hanekom, Willem A., van Rooyen, Michele, Shi, Zhongkai, Bennett, Sean

2015

Overview

New, more effective vaccines to prevent tuberculosis (TB) disease are needed urgently. H4:IC31 is an investigational vaccine that contains a fusion protein of the immunodominant antigens TB10.4 and Ag85B, formulated in IC31® adjuvant. We assessed the safety and immunogenicity of H4:IC31 in South African adults from a TB endemic setting. In this double blind, placebo controlled, phase I trial, Mycobacterium tuberculosis-uninfected, HIV-uninfected, healthy adults with a history of childhood BCG vaccination were randomly allocated to two intramuscular vaccinations with 5, 15, 50 or 150μg H4 formulated in 500nmol IC31®, two months apart. Vaccinees were followed for six months to assess safety; immunogenicity was measured by ELISpot and intracellular cytokine staining assays. Thirty-two participants received H4:IC31 and 8 received placebo. Injection site adverse events were common but mild; mild fatigue was the most common systemic adverse event. Frequencies of adverse events did not differ between dosage groups. Detectable antigen-specific CD4 T cell responses were induced by all doses of H4:IC31, but doses below 50μg induced the highest frequencies of CD4 T cells, comprised predominantly of IFN-γ+TNF-α+IL-2+ or TNF-α+IL-2+ cells. These memory responses persisted up to the end of follow up, on study day 182. H4:IC31 demonstrated an acceptable safety profile and was immunogenic in South African adults. In this trial, the 15μg dose appeared to induce the most optimal immune response.

• Publisher: Elsevier Ltd,Elsevier Limited
• Subject: adjuvants / Adolescent / Adult / Adults / Allergy and Immunology / Antigens / Antigens, Bacterial - administration & dosage / Antigens, Bacterial - immunology / CD4-positive T-lymphocytes / CD4-Positive T-Lymphocytes - immunology / childhood / Clinical trial / Clinical trials / cytokines / Cytokines - analysis / Deaths / Double-Blind Method / Drug Combinations / Enzyme-Linked Immunospot Assay / Female / H4:IC31 / Human immunodeficiency virus / Humans / Immune response / immunodominant epitopes / Immunogenicity / injection site / Injections, Intramuscular / Laboratories / Male / Microscopy / Middle Aged / Mycobacterium / Mycobacterium tuberculosis / Mycobacterium tuberculosis - immunology / Oligodeoxyribonucleotides - administration & dosage / Oligodeoxyribonucleotides - adverse effects / Oligopeptides - administration & dosage / Oligopeptides - adverse effects / Pharmacists / placebos / Placebos - administration & dosage / Public health / randomized clinical trials / Safety / South Africa / staining / Staining and Labeling / The trial was registered with the South African National Clinical Trials Register (number DoH 27-1108-2525) and ClinicalTrials.gov (NCT02109874) / Tuberculosis / Tuberculosis Vaccines - administration & dosage / Tuberculosis Vaccines - adverse effects / Tuberculosis Vaccines - immunology / Urine / vaccination / Vaccine / Vaccines / Young Adult