A Recombinant Modified Vaccinia Ankara Vaccine Encoding Epstein–Barr Virus (EBV) Target Antigens: A Phase I Trial in UK Patients with EBV-Positive Cancer Journal Articles uri icon

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abstract

  • AbstractPurpose: Epstein–Barr virus (EBV) is associated with several cancers in which the tumor cells express EBV antigens EBNA1 and LMP2. A therapeutic vaccine comprising a recombinant vaccinia virus, MVA-EL, was designed to boost immunity to these tumor antigens. A phase I trial was conducted to demonstrate the safety and immunogenicity of MVA-EL across a range of doses.Experimental Design: Sixteen patients in the United Kingdom (UK) with EBV-positive nasopharyngeal carcinoma (NPC) received three intradermal vaccinations of MVA-EL at 3-weekly intervals at dose levels between 5 × 107 and 5 × 108 plaque-forming units (pfu). Blood samples were taken at screening, after each vaccine cycle, and during the post-vaccination period. T-cell responses were measured using IFNγ ELISpot assays with overlapping EBNA1/LMP2 peptide mixes or HLA-matched epitope peptides. Polychromatic flow cytometry was used to characterize functionally responsive T-cell populations.Results: Vaccination was generally well tolerated. Immunity increased after vaccination to at least one antigen in 8 of 14 patients (7/14, EBNA1; 6/14, LMP2), including recognition of epitopes that vary between EBV strains associated with different ethnic groups. Immunophenotypic analysis revealed that vaccination induced differentiation and functional diversification of responsive T-cell populations specific for EBNA1 and LMP2 within the CD4 and CD8 compartments, respectively.Conclusions: MVA-EL is safe and immunogenic across diverse ethnicities and thus suitable for use in trials against different EBV-positive cancers globally as well as in South-East Asia where NPC is most common. The highest dose (5 × 108 pfu) is recommended for investigation in current phase IB and II trials. Clin Cancer Res; 20(19); 5009–22. ©2014 AACR.

authors

  • Price, David
  • Taylor, Graham S
  • Jia, Hui
  • Harrington, Kevin
  • Lee, Lip Wai
  • Turner, James
  • Ladell, Kristin
  • Price, David A
  • Tanday, Manjit
  • Matthews, Jen
  • Roberts, Claudia
  • Edwards, Ceri
  • McGuigan, Lesley
  • Hartley, Andrew
  • Wilson, Steve
  • Hui, Edwin P
  • Chan, Anthony TC
  • Rickinson, Alan B
  • Steven, Neil M

publication date

  • October 1, 2014

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