First-in-Human Evaluation of the Safety and Immunogenicity of a Recombinant Adenovirus Serotype 26 HIV-1 Env Vaccine (IPCAVD 001)

Publication Type
Journal Article
Year of Publication
Baden, LR; Walsh, SR; Seaman, MS; Tucker, RP; Krause, KH; Patel, A; Johnson, JA; Kleinjan, J; Yanosick, KE; Perry, J; Zablowsky, E; Abbink, P; Peter, L; Iampietro, MJ; Cheung, A; Pau, MG; Weijtens, M; Goudsmit, J; Swann, E; Wolff, M; Loblein, H; Dolin, R
J Infect Dis
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Date Published
Background. We report the first-in-human safety and immunogenicity assessment of a prototype Ad26 vector-based human immunodeficiency virus (HIV) vaccine in humans. Methods. Sixty Ad26-seronegative, healthy, HIV-uninfected subjects were enrolled in a randomized, double-blinded, placebo-controlled, dose-escalation phase 1 study. Five groups of 12 subjects received 10(9)-10(11) vp of the Ad26-EnvA vaccine (N = 10/group) or placebo (N = 2/group) at weeks 0 and 24 or weeks 0, 4, and 24. Safety and immunogenicity were assessed. Results. Self-limited reactogenicity was observed after the initial immunization at the highest (10(11) vp) dose. No product-related SAEs were observed. All subjects who received the Ad26-EnvA vaccine developed Ad26 NAb titers, EnvA-specific enzyme-linked immunosorbent assays (ELISA) titers, and EnvA-specific enzyme-linked immunospot assays (ELISPOT) responses. These responses persisted at week 52. At week 28 in the 10(9), 10(10), 10(11) vp 3-dose and the 10(10) and 5 × 10(10) vp 2-dose groups, geometric mean EnvA ELISA titers were 6113, 12 470, 8545, 3470, and 9655 and mean EnvA ELISPOT responses were 397, 178, 736, 196, and 1311 SFC/10(6) peripheral blood mononuclear cells, respectively. Conclusion. This Ad26 vectored vaccine was generally safe and immunogenic at all doses tested. Reactogenicity was minimal with doses of 5 × 10(10) vp or less. Ad26 is a promising new vaccine vector for HIV-1.