The mRNA-1647 vaccine: A promising step toward the prevention of cytomegalovirus infection (CMV)

Hum Vaccin Immunother. 2025 Dec;21(1):2450045. doi: 10.1080/21645515.2025.2450045. Epub 2025 Jan 17.

Abstract

Cytomegalovirus (CMV) is a leading cause of congenital infections and significant health complications in immunocompromised individuals. With no licensed CMV vaccine available, the development of the mRNA-1647 offers promising advancements in CMV prevention. We have reviewed results from Phase 1 and 2 clinical trials of the mRNA-1647 vaccine, demonstrating robust immune responses in both seronegative and seropositive participants. Vaccines exhibited significantly elevated neutralizing antibody titers against CMV, particularly in fibroblast and epithelial cells, with sustained responses lasting up to 18 months post-vaccination. The mRNA-1647 vaccine triggered strong T-cell and memory B-cell responses, suggesting its potential for long-term protection against CMV infection. The ongoing Phase 3 CMVictory trial evaluates the safety and immunogenicity of mRNA-1647 in women of childbearing age, with preliminary data showing promise in preventing congenital CMV transmission. This vaccine could significantly reduce CMV-related morbidity and mortality, particularly in newborns and immunocompromised individuals, addressing a critical unmet medical need.

Keywords: Cytomegalovirus; congenital infection; immunogenicity; mRNA-1647; public health; vaccine.

Publication types

  • Review

MeSH terms

  • Antibodies, Neutralizing* / blood
  • Antibodies, Neutralizing* / immunology
  • Antibodies, Viral / blood
  • Antibodies, Viral / immunology
  • B-Lymphocytes / immunology
  • Clinical Trials, Phase I as Topic
  • Cytomegalovirus Infections* / immunology
  • Cytomegalovirus Infections* / prevention & control
  • Cytomegalovirus Vaccines* / administration & dosage
  • Cytomegalovirus Vaccines* / immunology
  • Cytomegalovirus* / genetics
  • Cytomegalovirus* / immunology
  • Female
  • Humans
  • T-Lymphocytes / immunology
  • mRNA Vaccines

Substances

  • Cytomegalovirus Vaccines
  • Antibodies, Neutralizing
  • Antibodies, Viral
  • mRNA-1647 cytomegalovirus vaccine
  • mRNA Vaccines