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IDWeek 2025: first clinical data for two mRNA HSV vaccine candidates

Published:

At IDWeek 2025 (19–22 October, Atlanta), interim clinical data were presented for two mRNA herpes vaccine candidates: BioNTech's prophylactic BNT163 (Phase 1) and Moderna's therapeutic mRNA-1608 (Phase 1/2). Both are early-stage safety and immune-response read-outs shared as conference abstracts — encouraging early signals, not evidence that either prevents or controls disease.

At IDWeek 2025, two of the mRNA herpes vaccine programs we track reported their first public clinical data — a useful moment to note precisely because it is easy to over-read.

  • BNT163 (BioNTech), a prophylactic candidate, reported Phase 1 safety and immune-response data. A Phase 1 study asks whether a vaccine is safe and provokes an immune response — not whether it prevents infection. See the research entry.
  • mRNA-1608 (Moderna), a therapeutic candidate, reported interim Phase 1/2 safety, immune-response, and exploratory clinical-endpoint data. See the research entry.

Both read-outs were conference abstracts, not peer-reviewed publications, and both are early-stage. They tell us these programs are progressing and generating immune responses — not that either vaccine works. (Moderna later discontinued mRNA-1608 in November 2025.)

Sources

  1. Safety and Immunogenicity of BNT163, a Trivalent mRNA HSV Vaccine Candidate for Genital Herpes (abstract P-105) — Open Forum Infectious Diseases (IDWeek 2025) , October 2025
  2. mRNA-1608, an mRNA-Based Therapeutic Genital Herpes Vaccine Candidate: Interim Results from a Phase 1/2 Trial (abstract 642) — Open Forum Infectious Diseases (IDWeek 2025) , October 2025