Table 3.
CalcuSyn analysis of PSI-352938 combination studies with IFN-α or ribavirin
| Combination and ratioa | Combination indexb |
rc | ||
|---|---|---|---|---|
| EC50 | EC75 | EC90 | ||
| PSI-352938 and IFN-α | ||||
| 1:40 | 0.74 | 0.71 | 0.69 | 0.99 |
| 1:20 | 0.68 | 0.71 | 0.74 | 0.97 |
| 1:10 | 0.88 | 0.76 | 0.65 | 0.97 |
| 1:5 | 1.02 | 0.87 | 0.74 | 0.98 |
| Ribavirin and PSI-352938 | ||||
| 400:1 | 0.59 | 0.6 | 0.62 | 0.98 |
| 200:1 | 0.63 | 0.67 | 0.72 | 0.99 |
| 100:1 | 0.44 | 0.52 | 0.60 | 0.95 |
| 50:1 | 0.36 | 0.41 | 0.46 | 0.91 |
a
Compounds were combined in a checkerboard format, where 10 different concentrations of PSI-352938 were added horizontally and 8 different concentrations of IFN-α or ribavirin were added vertically to a 96-well plate. For each ratio indicated, at least six different combinations of PSI-352938 and IFN-α or ribavirin were included for calculations of the combination index value.
b
Combination index values at 50%, 75%, and 90% inhibition were calculated using the CalcuSyn program.
c
The r value is the linear correlation coefficient that indicates the goodness of fit for the data.