Potency and selectivity of rofecoxib in in vitro assays
| Assay | IC50 | |
|---|---|---|
| Rofecoxib | Indomethacin | |
| PGE2 production by osteosarcoma cells (COX-2) | 26 ± 10 nM (n = 5) | 21 ± 6 nM (n = 7) |
| PGE2 production by U937 cells (COX-1) | >50 μM (n = 4) | 7 ± 1 nM (n = 5) |
| PGE2 production by CHO [COX-2] cells | 18 ± 7 nM (n = 6) | 27 ± 6 nM (n = 12) |
| PGE2 production by CHO [COX-1] cells | >15 μM (n = 3) | 18 ± 2 nM (n = 9) |
| PGE2 production by LPS-induced human mononuclear cells (COX-2) | 45 ± 7 nM (n = 11) | 57 ± 14 nM (n = 18) |
| PGE2 production by LPS-induced rat mononuclear cells (COX-2) | 41 ± 10 nM (n = 10) | |
| PGE2 production by Sf9 [rat COX-2] cells | 46 ± 9 nM (n = 3) | 18 nM (n = 2) |
| PGE2 production by human kidney microsomes | 14 μM (n = 4) | 0.1–0.4 μM (n = 8) |
| PGE2 production by rat kidney microsomes | >30 μM (n = 3) | 0.3 ± 0.1 μM (n = 3) |
| PGE2 production by dog kidney microsomes | >30 μM (n = 2) | ∼0.3 μM (n = 2) |
| PGE2 production by U937 microsomes (low substrate) | 2.0 ± 0.5 μM (n = 7) | 19.8 ± 0.2 nM (n = 23) |
| Purified human COX-2 | 0.34 μM (n = 2) | 0.6 ± 0.1 μM (n = 16) |
| Purified human COX-2 with detergent | 0.40 μM (n = 2) | 0.4 ± 0.1 μM (n = 16) |
| Purified human COX-1 (low substrate) | 26.3 ± 6.4 μM (n = 11) | N.D. |
| 15-Lipoxygenase | >20 μM (n = 2) | N.D. |
| LTB4 production by human PMN leukocytes | >25 μM (n = 3) | N.D. |
| 12-HETE and TXB2 production by Ca2+ionophore-challenged platelets | >20 μM (n = 5) | N.D. |
N.D., not determined.