Nature Medicine, Published online: 24 April 2026; doi:10.1038/s41591-026-04301-0
A 22-year-old patient with cystic fibrosis and chronic, drug-resistant Bordetella bronchialis infection received compassionate-use phage therapy. Serum samples revealed that pre-existing antiphage immunity existed before treatment, indicating that future studies must evaluate antiphage immunity across the entire treatment regimen.
