DNA Vaccine Delivered by a Needle-Free Injection Device Improves Potency of Priming for Antibody and CD8+ T-Cell Responses after rAd5 Boost in a Randomized Clinical Trial

• Published in: PloS one Vol. 8; no. 4; p. e59340
• Main Authors: Graham, Barney S., Enama, Mary E., Nason, Martha C., Gordon, Ingelise J., Peel, Sheila A., Ledgerwood, Julie E., Plummer, Sarah A., Mascola, John R., Bailer, Robert T., Roederer, Mario, Koup, Richard A., Nabel, Gary J.
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 08.04.2013; Public Library of Science (PLoS)
• Subjects: Adenoviridae - genetics; Adenoviruses; Adolescent; Adult; Adults; Antibodies, Viral - immunology; Avian flu; Binding sites; Biology; Carbon dioxide; CD4 antigen; CD8 antigen; CD8-Positive T-Lymphocytes - immunology; Clinical trials; Delivery scheduling; Deoxyribonucleic acid; DNA; DNA vaccines; DNA, Recombinant - genetics; Dose-Response Relationship, Immunologic; Drug delivery systems; Enzyme-linked immunosorbent assay; Female; Hepatitis; HIV; HIV-1 - immunology; HIV-1 - metabolism; Human immunodeficiency virus; Humans; Immunity, Cellular - immunology; Immunity, Humoral - immunology; Immunization, Secondary - methods; Immunogenicity; Infectious diseases; Injection; Injections; Interferon; Lymphocytes T; Male; Medicine; Middle Aged; Peptide Fragments - metabolism; Priming; Safety; Safety regulations; Studies; Syringes; T cells; Vaccination; Vaccination - instrumentation; Vaccines; Vaccines, DNA - administration & dosage; Vaccines, DNA - adverse effects; Vaccines, DNA - genetics; Vaccines, DNA - immunology; Vice presidents (Organizations); West Nile virus; Young Adult; γ-Interferon; United States > US; Maryland
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0059340

DNA vaccine immunogenicity has been limited by inefficient delivery. Needle-free delivery of DNA using a CO2-powered Biojector® device was compared to delivery by needle and syringe and evaluated for safety and immunogenicity. Forty adults, 18-50 years, were randomly assigned to intramuscular (IM) vaccinations with DNA vaccine, VRC-HIVDNA016-00-VP, (weeks 0, 4, 8) by Biojector® 2000™ or needle and syringe (N/S) and boosted IM at week 24 with VRC-HIVADV014-00-VP (rAd5) with N/S at 10(10) or 10(11) particle units (PU). Equal numbers per assigned schedule had low (≤500) or high (>500) reciprocal titers of preexisting Ad5 neutralizing antibody. 120 DNA and 39 rAd5 injections were given; 36 subjects completed follow-up research sample collections. IFN-γ ELISpot response rates were 17/19 (89%) for Biojector® and 13/17 (76%) for N/S delivery at Week 28 (4 weeks post rAd5 boost). The magnitude of ELISpot response was about 3-fold higher in Biojector® compared to N/S groups. Similar effects on response rates and magnitude were observed for CD8+, but not CD4+ T-cell responses by ICS. Env-specific antibody responses were about 10-fold higher in Biojector-primed subjects. DNA vaccination by Biojector® was well-tolerated and compared to needle injection, primed for greater IFN-γ ELISpot, CD8+ T-cell, and antibody responses after rAd5 boosting. ClinicalTrials.gov NCT00109629.