Selective Inhibitors of Cyclooxygenase-2

Structures and selectivity ratios of four coxibs as measured in human whole blood assays. In addition to the two COX-2 inhibitors that are currently on the market (i.e., celecoxib and rofecoxib), data are shown for two COX-2 inhibitors that are currently in clinical development (i.e., valdecoxib and etoricoxib).

^a IC₅₀ is the inhibitor concentration necessary to reduce COX rates by 50 percent.

^b All data were obtained through the human whole blood assay (17).

^c The selectivity of each compound for the COX-2 isoform is determined as the ratio IC50 (COX-1)/IC50 (COX-2).