Table 4.
Ratios of achievable concentrations of Respiratory syncytial virus (RSV) antivirals to their corresponding IC50s
| Antiviral | Route of administration | Fluid measured | Ratio of antiviral concentration (mg/dL) to IC50 (ng/mL) | |
|---|---|---|---|---|
| Peak | Trough | |||
| MDT‐637a | Aerosol | Respiratory secretion | 6041‐fold a , b | 1481‐folda , b |
| Ribavirin | Aerosol | Respiratory secretion | 25‐fold35 | 3.29‐fold35 |
| Ribavirin | Oral (single‐dose) | Plasma | 0.05‐fold38, 39, 40 | ‐ |
| Ribavirin | Oral (multiple‐dose) | Plasma | 0.22‐fold38, 39, 40 | 0.13‐fold35 |
| Ribavirin | Intravenous (single‐dose) | Plasma | 0.25‐fold41 | 0.004‐fold41 |
a
1/180 aqueous to simulated lung fluid solubility ratio is used in the calculations.
b
Mean of achievable nasal wash concentrations are from phase I clinical trial data of 66 μg aerosol TID and 132 μg aerosol TID. Peak and trough concentrations from the both dosing groups were measured pre‐dosing and 15 minutes post‐aerosol dosing on the 6th day of treatment and then averaged the values.