Pharmacokinetics of a single dose of oclacitinib maleate as a top dress in adult horses.

This study examines how a drug called oclacitinib maleate disperses and reacts in the bodies of adult horses after it’s administered in a single dosage.

Study Set Up

The researchers chose six adult horses with an average weight of 528 kilograms for the study. These horses were each given 0.5 milligrams of the drug oclacitinib maleate for every kilogram of their weight:

• This equates to a dosage of about 264 milligrams per horse if each horse weighed exactly the average weight of 528 kilograms.

Procedure

• A blood sample was taken from each horse before administering the drug to establish a baseline.
• Subsequent blood samples were then taken at set intervals – 15 minutes, 30 minutes, 45 minutes, 1 hour, 2 hours, 4 hours, 6 hours, 8 hours, 12 hours, 24 hours, 48 hours and 72 hours – after the drug was administered.
• The amount of oclacitinib maleate in the plasma of the blood was measured using a process known as liquid chromatography/mass spectrometry. This method separates and identifies the amount and type of chemicals in a solution — in this case, the plasma from the horse’s blood.

Results

• The drug’s rate of dispersion and interaction in the body (its pharmacokinetic parameters) followed a one-compartment model. In pharmacology, a one-compartment model assumes the body acts as a single, unified system where the substance is evenly distributed and eliminated at the same time.
• The average amount of oclacitinib maleate detected in the plasma (C) was 486 nanograms per milliliter, with a range of 423 to 549 nanograms per milliliter.
• The average time it took to reach the peak concentration (T) was calculated to be 1.7 hours, with the actual time varying between 0.3 to 3.1 hours.
• The lifespan of the drug in the body (T), or the time during which the drug is therapeutic without being toxic, is estimated to be between 7.5 to 8 hours.

The findings offer a time-based overview of the journey of oclacitinib maleate in the body of a horse, providing key information on the pharmacokinetics of the drug.