A pharmacodynamic and pharmacokinetic study with vedaprofen in an equine model of acute nonimmune inflammation.

This research article involves a scientific study on the effects of vedaprofen, a drug, on inflammation in ponies. Six ponies underwent a test where a mild inflammatory reaction was triggered, and vedaprofen was used to inhibit inflammation. The researchers report that the drug showed significant effects on overall inflammation and displayed enantioselective pharmacokinetics, with the R(-) form of vedaprofen showing higher plasma concentrations than the S(+) form.

Study Design and Procedure

• The researchers conducted a two-period cross-over study involving six ponies.
• They induced a mild acute inflammatory reaction in the subjects by implanting sponges soaked in carrageenan—a compound known to cause inflammation—subcutaneously in the neck of the horses.
• The drug vedaprofen was then administered intravenously to the subjects at a dosage of 1 mg/kg to gauge its effects on the induced inflammation.

Effects of Vedaprofen on Inflammation

• The researchers found that vedaprofen led to a significant and prolonged inhibition of ex vivo serum thromboxane B2 (TXB2) synthesis. TXB2 is a biomarker often used to measure the level of inflammation.
• The drug also temporarily inhibited the synthesis of exudate prostaglandin E2 (PGE2) and TXB2, both of which are involved in inflammatory responses.
• Vedaprofen partially inhibited swelling and the infiltration of leucocytes (white blood cells that fight off infections) into the exudate, the fluid that oozes out of a wound or due to inflammation.

Enantioselective Pharmacokinetics of Vedaprofen

• The study found that vedaprofen displayed enantioselective pharmacokinetics—that is, the drug’s distribution, metabolism, and excretion differed between the two enantiomers, R(-) and S(+).
• Specifically, the plasma concentrations, or the amount of the drug in the subjects’ blood, of the R(-) enantiomer were higher than those of the S(+) enantiomer.
• The relative amounts of the two enantiomers varied over time, increasing from a ratio of 69:31 at 5 minutes to 96:4 at 3 hours post-administration.
• The average amount of the drug in the body over time (as measured by the area under the “concentration-time” curve, or AUC) was higher for the R(-) enantiomer.

The Therapeutic Significance of Vedaprofen

• The research also examined the penetration of vedaprofen into the inflammatory exudate, finding that this, too, was enantioselective.
• Additionally, the researchers found that vedaprofen was highly protein-bound in both plasma and exudate, which can affect how the drug is distributed in the body.
• Finally, the researchers discuss the implications of these findings for the therapeutic use of vedaprofen in treating inflammation, though more details on their discussion would be available in the full article.