This double-blind, randomized, controlled, multicenter field study was conducted to compare the safety and efficacy of firocoxib chewable tablets and carprofen tablets. Dogs enrolled in the study had to meet specific criteria, including being lame for at least 4 weeks and having radiographic evidence of osteoarthritis. At each clinic, replicates of 2 dogs were formed as they enrolled, and within these replicates, each dog was randomly allocated to receive either carprofen (at least 4 mg/kg per day) or firocoxib (at least 5 mg/kg per day). A total of 218 dogs were enrolled in the study ranging in weight from 3.4 to 86 kg and from 7 months to 19 years of age. Any other antiarthritic agents, such as NSAIDs or glycosaminoglycans, had to be discontinued for at least 7 days before the start of the study and corticosteroids for at least 30 days. Assessments were made by both the veterinarian and the owners. At the end of 30 days, veterinarians reported improvement in lameness, pain on manipulation/palpation, range of motion, and joint swelling in 92.5% of the dogs treated with firocoxib and 92.4% of those treated with carprofen. The reduction in lameness in the dogs treated with firocoxib was significantly greater than that in the dogs treated with carprofen. The pet owners' evaluation reported that 96.2% of the dogs treated with firocoxib and 92.4% of the dogs treated with carprofen had improved. Study sponsored by Merial

COMMENTARY: Firocoxib is a cyclooxygenase-2 selective NSAID that is approved for use in dogs in the United States and elsewhere. This study from Europe, and similar studies in the United States-including the 1000-dog PET study1-have shown that firocoxib can relieve the pain of osteoarthritis, a common ailment in older dogs.

Clinical Effectiveness and Safety of a New NSAID, Firocoxib: A 1,000 Dog Study. Ryan WG, Moldave K, Carithers D. Vet Ther 7: 119-126, 2006. Clinical evaluation of firocoxib and carprofen for the treatment of dogs with osteoarthritis. Pollmeier M, Toulemonde C, Fleishman C, Hanson PD. Vet Rec 159: 547-551, 2006.