The Effects of Carprofen and Phycox in Dogs with Naturally Occurring Clinical Elbow Osteoarthritis: A Randomized, Double-Blinded, Multicenter Pilot Study

Introduction: The purpose of this study was to examine the comparative effects of treatment with Phycox, a C-phycocyanin-based nutraceutical or carprofen in dogs with clinical elbow osteoarthritis (OA).

Materials and Methods: Twenty-one client-owned dogs with unilateral or bilateral elbow joint OA were selected for the randomized, double-blinded, multicenter study. Two groups were used; treatment group: Phycox, control group: carprofen. All dogs were treated for 24 weeks. Assessments made before and during the treatment period included force plate analysis, accelerometry, goniometry, pain and lameness evaluations, canine brief pain inventories, and synoviocentesis for concentrations of select inflammatory and degradation markers. Statistical analysis was performed using a split-plot ANOVA and Bonferroni corrections post-hoc with significance at p < 0.05.

Results: Final enrollments: Phycox group = 10 dogs, carprofen group = 10 dogs. There were no differences between groups in ground reaction forces or clinical lameness scores. The Phycox group recorded greater accelerometer activity at 12 weeks (p = 0.046) and joint extension at 24 weeks (p = 0.0003). Pain scores were lower for the carprofen group at 20 and 24 weeks (p = 0.008, p = 0.001). Synovial concentrations of matrix metalloproteinase-3 were lower in the Phycox group at 24 weeks (p = 0.013), while PGE₂ was lower in the carprofen group at 12 and 24 weeks (p = 0.047, p = 0.023).

Discussion/Conclusion: Although Phycox and carprofen provide clinical efficacy when treating OA patients, Phycox may provide a greater potential to modulate the biochemical OA environment in the dog.

Acknowledgement: Funded by a grant from Dechra. Funding sponsor had no influence on study design, results, or preparation of manuscripts.

No conflict of interest has been declared by the author(s).