Publications by authors named "Vlad Popovic"

Introduction: Hepatitis B remains a major cause of death and morbidity worldwide. Universal childhood immunization programs have been very successful, but many adults remain unprotected or are not optimally protected. PreHevbrio [Hepatitis B Vaccine (recombinant)] is a highly immunogenic 3-antigen (S/pre-S1/pre-S2) hepatitis B vaccine (3A-HBV) that recently received marketing authorization in the United States (2021), the European Union, United Kingdom (2022 - brand name PreHevbri), and Canada (2022- brand name PreHevbrio) for the prevention of infection caused by all known subtypes of the hepatitis B virus and the delta virus in adults 18 years and older.

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Importance: There is a need for improved immunogenicity of hepatitis B virus (HBV) vaccines among young adults with risk of infection.

Objectives: To demonstrate manufacturing equivalence of a 3-antigen (3A) HBV vaccine, evaluate noninferiority of seroprotection rate (SPR) of 3A-HBV vs single-antigen (1A) HBV after 2 and 3 vaccine doses, and compare safety and reactogenicity between 3A-HBV and 1A-HBV vaccines.

Design, Setting, And Participants: This phase 3, double-blinded, randomized clinical trial included healthy adults aged 18 to 45 years randomized to 1 of three 3A-HBV groups or 1 control group receiving 1A-HBV.

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Background: Sci-B-Vac®, a 3-antigen hepatitis B vaccine (3A-HBV), contains all three recombinant hepatitis B virus (HBV) envelope proteins (S, pre-S1, and pre-S2). In 2005, 3A-HBV manufacturing transferred facilities (A to B), where it continues to be manufactured.

Methods: This phase 3, single-blind, randomized study, conducted at one site in Vietnam, compared efficacy and safety among two 3A-HBV lots, lot A and lot B, and a single-antigen hepatitis B vaccine (1A-HBV), Engerix-B®.

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Background: The seroprotection rate (SPR) of hepatitis B vaccination in adults is suboptimal. The aim of this study was to compare the SPR of a tri-antigenic hepatitis B vaccine (TAV), with a mono-antigenic vaccine (MAV) in adults of all ages.

Methods: This was a multicentre, double-blind, phase 3, randomised controlled trial (PROTECT) comparing the immunogenicity and safety of TAV with MAV in 28 community and hospital sites in the USA, Finland, Canada, and Belgium.

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Background: Sci-B-Vac® is a tri-antigenic recombinant Hepatitis B vaccine (TAV) containing the small (s), medium (pre-S2) and large (pre-S1) hepatitis B surface (HBs) antigens. To comply with vaccine licensure, a new reference standard batch was qualified by characterizing the seroprotection rate (SPR) for anti-HBs titers ≥10 mIU/mL, following vaccination.

Methods: Ninety-one healthy adults aged 20-40 years were enrolled in an open label, single-arm phase IV study receiving three IM doses of 10 μg TAV at 0, 1 and 6 months.

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