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PHARMACOKINETICS OF A SINGLE INTRAMUSCULAR DOSE OF ROBENACOXIB IN TIGERS (PANTHERA TIGRIS)
Liandrie Swanepoel1, Sherry Cox2, Andrew Cushing3
1Small Animal Clinical Sciences, University of Tennessee College of Veterinary Medicine, Knoxville, TN 37996, USA.
Summary
This study explored robenacoxib pharmacokinetics in tigers. A 0.25 mg/kg intramuscular dose maintained therapeutic plasma concentrations for up to 12 hours in these big cats.
Area of Science:
- Veterinary Pharmacology
- Wildlife Health
- Pharmacokinetics
Background:
- Robenacoxib is a non-steroidal anti-inflammatory drug (NSAID) used in domestic animals.
- Limited pharmacokinetic data exists for robenacoxib in nondomestic felids.
- Understanding robenacoxib's behavior in tigers is crucial for pain management in this species.
Purpose of the Study:
- To determine the pharmacokinetics of robenacoxib in adult tigers (Panthera tigris).
- To establish a safe and effective dosing regimen for robenacoxib in tigers.
- To assess the duration of therapeutic drug concentrations following administration.
Main Methods:
- Pilot study involving nine adult tigers with varying doses (0.25–2 mg/kg) via subcutaneous (SC) or intramuscular (IM) injection.
- Selection of 0.25 mg/kg IM dose for further study based on pilot data and ease of administration.
- Pharmacokinetic analysis in eight additional tigers using sparse sampling (0–20 hours post-dose) and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) for plasma concentration measurement.
Main Results:
- Mean maximum observed plasma concentration (Cmax) of robenacoxib was 686 ng/ml.
- Time to maximum concentration (Tmax) was 1 hour, with an elimination half-life (t1/2) of 3.2 hours.
- Plasma concentrations remained above 10 ng/ml (therapeutic threshold from domestic cat studies) for up to 12 hours after a single 0.25 mg/kg IM dose.
Conclusions:
- A single 0.25 mg/kg IM dose of robenacoxib provides sustained therapeutic concentrations in tigers.
- This pharmacokinetic profile supports the potential use of robenacoxib for pain management in tigers.
- This is the first pharmacokinetic investigation of robenacoxib in a nondomestic felid species.
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