Safety and immunogenicity of modified vaccinia Ankara-Bavarian Nordic smallpox vaccine in vaccinia-naive and experienced human immunodeficiency virus-infected individuals: An open-label, controlled clinical phase II trial

Academic Article


  • Background. First- and second-generation smallpox vaccines are contraindicated in individuals infected with human immunodeficiency virus (HIV). A new smallpox vaccine is needed to protect this population in the context of biodefense preparedness. The focus of this study was to compare the safety and immunogenicity of a replicationdeficient, highly attenuated smallpox vaccine modified vaccinia Ankara (MVA) in HIV-infected and healthy subjects. Methods. An open-label, controlled Phase II trial was conducted at 36 centers in the United States and Puerto Rico for HIV-infected and healthy subjects. Subjects received 2 doses of MVA administered 4 weeks apart. Safety was evaluated by assessment of adverse events, focused physical exams, electrocardiogram recordings, and safety laboratories. Immune responses were assessed using enzyme-linked immunosorbent assay (ELISA) and a plaque reduction neutralization test (PRNT). Results. Five hundred seventy-nine subjects were vaccinated at least once and had data available for analysis. Rates of ELISA seropositivity were comparably high in vaccinia-naive healthy and HIV-infected subjects, whereas PRNT seropositivity rates were higher in healthy compared with HIV-infected subjects. Modified vaccinia Ankara was safe and well tolerated with no adverse impact on viral load or CD4 counts. There were no cases of myo-/pericarditis reported. Conclusions. Modified vaccinia Ankara was safe and immunogenic in subjects infected with HIV and represents a promising smallpox vaccine candidate for use in immunocompromised populations.
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    Author List

  • Overton ET; Stapleton J; Frank I; Hassler S; Goepfert PA; Barker D; Wagner E; von Krempelhuber A; Virgin G; Meyer TP
  • Volume

  • 2
  • Issue

  • 2