The primary objective was to demonstrate equivalence between a.m. and p.m. dosing of celecoxib 200 mg q.d. An equivalence assessment of q.d. vs b.i.d. dosing was a secondary objective.
In this randomized, double-blind study, patients with symptomatic osteoarthritis of the knee or hip were randomized to receive celecoxib 200 mg q.d. a.m., celecoxib 200 mg q.d. p.m. or celecoxib 100 mg b.i.d. The primary outcome variable, measured at week 12 on a 0- to 10-point integrated scale, was patient satisfaction assessment (pain relief, walking/bending, and willingness to continue medication). Equivalence was declared if the 95% confidence interval (CI) of the difference (a.m. q.d. vs p.m. q.d., b.i.d. vs q.d.) fell within the interval of -2 to +2.
A total of 697 patients were enrolled in this trial. For the a.m. vs p.m. comparison, the 95% CIs were within the prespecified equivalence criteria for all three measures of patient satisfaction: pain relief, mean -0.2, 95% CI -0.53 to 0.68; ability to walk and bend, mean -0.2, 95% CI -0.54 to 0.64; willingness to continue medication, mean -0.7, 95% CI -0.98 to 0.49. The 95% CIs for the q.d. vs b.i.d. comparison were also within the -2 to +2 interval.
Regardless of the time of day at which celecoxib 200 mg q.d. is administered, patients are equally satisfied with the pain relief, ability to walk and bend, and willingness to continue medication.