A multicenter, randomized, double blind study comparing lornoxicam with diclofenac in osteoarthritis

To compare the efficacy and tolerability of lornoxicam and diclofenac in the treatment of patients with osteoarthritis (OA) over 12 weeks and to assess the efficacy and tolerability of lornoxicam over a followup period of 40 weeks.

In a double blind, parallel group study, 135 patients (mean age 63 years) with OA of the hip and/or knee were randomized to receive lornoxicam 4 mg 3 times daily (tid), lornoxicam 8 mg twice daily (bid), or diclofenac 50 mg tid for 12 weeks. 85 patients who completed this 12 week treatment period subsequently received lornoxicam 4 mg tid or 8 mg bid for up to 40 weeks.

Over the initial 12 week treatment period, intention-to-treat analysis revealed improvements in the functional index of severity for OA in all 3 groups by -1.5 to -1.9 points and pairwise testing demonstrated significant intergroup equivalence (p < 0.033). Confirmatory analysis demonstrated the expected efficacy as outlined in the sample size calculation. The percentage of patients showing improvements in disease activity (about 46%) and pain intensity (42 to 48%) was also similar and a clear majority of patients also reported "some" or "excellent" pain relief (80 to 89%). A per protocol analysis produced similar results. During the 40 week lornoxicam followup treatment period there was slight deterioration in the functional index of severity of OA (0.3 to 1.1 points). This minor change may reflect the natural course of the disease rather than a loss of efficacy in lornoxicam. Disease activity and pain intensity continued to improve but in a lesser proportion of patients (< 23%) compared to the previous phase. Nevertheless, a similar high percentage of patients (78 to 89%) reported "some" or "excellent" pain relief. Adverse events in both phases of this study were consistent with those commonly reported during treatment with nonsteroidal antiinflammatory drugs and included headache and gastrointestinal events. There was no difference in the frequency or severity of adverse events between any of the treatment groups. Lornoxicam was well tolerated in the long term.

Lornoxicam 4 mg tid and 8 mg bid were as effective as diclofenac 50 mg tid for the treatment of OA. There was no significant difference in tolerability of these regimens. Thus, lornoxicam appears to be a useful therapeutic alternative to diclofenac in patients with OA.