Table 1 Characteristics of drugs and mean IC-50 values (± standard deviation)
|  |  |  |  | Mean IC-50 for TNF-α inhibition | |
|---|---|---|---|---|---|
Drug | Target | Reduced folate carrier affinity (cell uptake) | Folylpolyglutamate synthetase affinity (cell retention) | Rheumatoid arthritis patients (n = 11) | Controls (n = 6) |
MTX | DHFR | ++ | + | 78 (77) nM | 57 (27) nM |
PT523 | DHFR | +++ | - | 5.8 (3.2) nM | 6.4 (8.3) nM |
ZD1694 | TS | +++ | +++ | 16 (26) nM | 4.8 (3.0) nM |
SSZ | NF-κB | - | - | 278 (216) μM | 191 (29) μM |