Preexisting Adenovirus Seropositivity Is Not Associated With Increased HIV-1 Acquisition in Three HIV-1 Vaccine Efficacy Trials

Division of Vaccine Research, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA.
The Journal of Infectious Diseases (Impact Factor: 6). 04/2012; 205(12):1806-10. DOI: 10.1093/infdis/jis285
Source: PubMed


The Step study of a recombinant adenovirus serotype 5 (Ad5)–based human immunodeficiency virus type 1 (HIV-1) vaccine revealed
an increased risk of HIV-1 acquisition in vaccinees who were Ad5 seropositive at baseline. We therefore investigated whether
preexisting Ad seropositivity to 7 different Ad serotypes was associated with increased risk of HIV-1 infection in 3 HIV-1
vaccine efficacy trials. In a case-control study involving 1570 adults enrolled in the VAX003 and VAX004 trials of a recombinant
protein subunit HIV-1 vaccine and in the Step study, we observed that preexisting seropositivity to multiple Ad serotypes
was not intrinsically associated with increased risk of HIV-1 acquisition.

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Available from: Susan Buchbinder, Sep 19, 2014
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    • "Pre - existing Ad5 seropositivity has been associated with HIV - 1 acquisition in the STEP trial ( Buchbinder et al . , 2008 ) , but not other non - Ad HIV - 1 vaccine efficacy trials ( Stephenson et al . , 2012 ) . Nevertheless in this study , the major rationale was to use Ad5 to generate V1 / V2 vaccine candidates via the " Antigen Capsid - Incorporation " strategy and confirm the V2 - specific antigenicity / immunogenicity on Ad5 ."
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