| Antiviral | EC50 ratio | Phenotype | Strain | Source | Marker | Assay | Reference |
|---|---|---|---|---|---|---|---|
| Maribavir | 2.00 | Low level resistance | Laboratory strain, Clinical Isolate | Recombinant | Details | Low level drug resistance linked to cytomegalovirus UL97 and UL27 mutations detected in maribavir clinical trials. (Sep 2026) |