Robenacoxib shows efficacy for the treatment of chronic degenerative joint disease-associated pain in cats: a randomized and blinded pilot clinical trial

Abstract

The main objective of this pilot clinical trial was to evaluate outcome measures for the assessment of the nonsteroidal anti-inflammatory drug (NSAID) robenacoxib in cats with degenerative joint disease-associated pain (DJD-pain). Otherwise healthy cats (n = 109) with DJD-pain entered a parallel group, randomized, blinded clinical trial. Cats received placebo (P) or robenacoxib (R) for two consecutive 3-week periods. Treatment groups were PP, RR, and RP. Actimetry and owner-assessment data were collected. Data were analyzed using mixed-effects and generalized mixed-effects linear models. Activity data showed high within-cat and between-cat variability, and 82.4% of the values were zero. Compared to placebo, mean total activity was higher (5.7%) in robenacoxib-treated cats (p = 0.24); for the 80th percentile of activity, more robenacoxib-treated cats had a > 10% increase in activity after 3 (p = 0.046) and 6 weeks (p = 0.026). Robenacoxib treatment significantly decreased owner-assessed disability, (p = 0.01; 49% reduction in disability; effect size ~ 0.3), and improved temperament (p = 0.0039) and happiness (p = 0.021) after 6 weeks. More robenacoxib-treated cats were successes at 6 weeks (p = 0.018; NNT: 3.8). Adverse effect frequencies were similar across groups. Results identified suitable endpoints for confirmatory studies, while also indicating efficacy of robenacoxib in cats with DJD-pain.

Figure 1

Patient recruitment and enrollment flowchart (CONSORT flowchart). n  number of patients; treatment groups: P placebo, R robenacoxib, ITT intent to treat analysis, PerProto per protocol analysis.

Figure 2

Example cumulative distribution function for a single cat (LAS-31), demonstrating a rightward shift of activity during treatment with robenacoxib, as compared against treatment with placebo. This indicates that the activity counts were higher while receiving robenacoxib. P values from the Kolmogorov–Smirnov test were < 0.0001 for the hypothesis that activity with robenacoxib > placebo, and 1.0 for placebo > robenacoxib. Analysis and graphical output performed using SAS software capabilities (Version 9, SAS Institute Inc., Cary, NC).

Figure 3

Study design and timeline. The blinded study started at Day 0. Screening (examinations, owner questionnaires, bloodwork, fitting the cat with an activity monitor) occurred 2 weeks (14 days) prior to Day 0. Cats were examined in the clinic, and owners completed assessments at Day 0 and Day 42. Owners visited the clinic alone to complete assessments on Day 21. Treatment period 1 (T1) was over days 0–21 (3 weeks); treatment period 2 (T2) was over days 22–42 (3 weeks).