OBJECTIVES

A study was conducted in France to confirm the efficacy and safety of the continuous use of Rimadyl® tablets administered orally at 4 mg/kg once daily for four months to relieve the clinical signs associated with chronic cases of osteoarthritis in dogs.

MATERIALS

One hundred and ten patients with typical clinical signs of osteoarthritis, which had been observed continuously for more than two weeks or recurrently over a longer period of time (i.e., "chronic cases"), were enrolled and treated with carprofen tablets (Rimadyl®) at 4 mg/kg once daily for four months. The overall severity of the osteoarthritic condition and the typical signs of osteoarthritis, including lameness, limitation of joint movement and pain on movement, were assessed using visual analogue scales (VAS) of 100 mm length, at study start (day 0) and thereafter at approximately days 5, 30, 60, 90 and 120. Hematological parameters were evaluated on days 0 and 120. Total proteins, albumin, urea, creatinine, alanine aminotransferase (ALAT), aspartate aminotransferase (ASAT) and serum bile acids were evaluated on days 0, 5, 60 and 120.

RESULTS

A high percentage of patients completed the study (97/110, 88%). Only two patients were withdrawn from the study for adverse events (gastro-enteritis) considered by the investigators to be related to Rimadyl®. The clinical signs associated with the osteoarthritic condition improved within 5 days of treatment start and improved further throughout the four-month treatment period. The percentage of patients with a substantial positive treatment effect (more than 20-mm decrease on VAS scale of overall severity of the condition) increased from 12% on day 5 to 45% on day 30 and to 74% on day 120. Mean VAS scores of overall severity and of the typical clinical signs of osteoarthritis decreased with continuous use of Rimadyl® (from 59.8 mm on day 0 to 37.8 mm on day 30 and 22.4 mm on day 120, for overall severity). The reduction in pain was rapid, clearly apparent by day 5 and continued to improve thereafter. There were no detrimental effects of the prolonged Rimadyl® treatment on hematological parameters, and renal and hepatic functions.

CONCLUSION

The continuous use of Rimadyl® tablets administered orally at 4 mg/kg once daily for four months to osteoarthritic dogs resulted in a safe and very substantial, progressive improvement in the clinical signs of osteoarthritis including pain.