The contribution of metabolites to the anti-inflammatory activity of flurbiprofen

Summary

The peak blood levels of flurbiprofen associated with a statistically significant inhibition of adjuvant arthritis in the rat are considerably lower than those found in man at effective antirheumatic doses. The possibility has been investigated that this apparent difference in effectiveness between the species might be accounted for by the biological activity of Metabolite 1, a major metabolite of flurbiprofen found in the serum and urine of the rat but only in the urine of man. The pharmacological activity of Metabolite 1 in animal tests, and its ability to inhibit prostaglandin synthesis in vitro were found to be much lower than those of flurbiprofen and the two drugs had similar half-lives in the rat. It is concluded, therefore, that this metabolite contributes very little towards the activity of flurbiprofen in the rat.

Key Words::

• Flurbiprofen
• metabolites
• pharmacology