Figure 4.

(A) Inhibition of LPS-stimulated plasma PGE₂, an index of COX-2 activity, ex vivo in volunteers receiving placebo, 800 mg of ibuprofen, and various doses of celecoxib. ∗∗, P < 0.01 when compared with placebo. (B) The relationship between LPS-stimulated plasma PGE₂ ex vivo, an index of COX-2 activity, and log plasma concentrations of celecoxib 2, 4, 6, and 24 hr after dosing. PGE₂ is expressed as a percentage of predosing values. A steep but variable dose-response is evident. ∗∗, P < 0.01 for comparisons with placebo.