Overview
- The Phase 3 trial enrolled about 9,400 participants but missed its prespecified statistical criterion because fewer Lyme cases occurred than planned, which Valneva says came down to a single case.
- Vaccinated participants recorded roughly 73%–75% fewer Lyme disease cases than those on placebo, with efficacy reported in people aged five and older.
- Pfizer says it remains confident in the vaccine’s potential and intends to file regulatory dossiers in the United States and European Union as additional Phase 3 data are awaited.
- Investors punished the news, with Valneva shares falling about 38%–40% on the Paris market on Monday.
- There is no approved human vaccine for Lyme disease, and the candidate works by inducing antibodies that feeding ticks ingest, blocking bacterial transmission.