Objective: To assess the efficacy and tolerability of sulfasalazine (SSZ) in the treatment of spondylarthropathy.
Methods: We conducted a 6-month randomized, placebo-controlled, double-blind, multicenter study of patients with spondylarthropathy whose disease had remained active despite treatment with nonsteroidal antiinflammatory drugs. Patients were treated with SSZ (3 gm/day) or placebo. The primary efficacy variables were the physician's and patient's overall assessments, pain, and morning stiffness. End points were analyzed in the intent-to-treat and completer patient populations; the time course of effect was analyzed in the completer patient population.
Results: Of the 351 patients enrolled, 263 (75%) completed the 6-month treatment period. The withdrawal rates were 35 (20%) and 53 (30%) in the placebo and SSZ groups, respectively. In the intent-to-treat analysis of end point efficacy, the between-treatment difference reached statistical significance only for 1 of the 4 primary outcome variables, the patient's overall assessment of disease activity, for which 60% of the patients taking SSZ improved by at least 1 point on a 5-point scale, in contrast to 44% of the patients taking placebo. Laboratory markers of inflammation also showed statistically significant change in favor of SSZ. In subgroup analysis, the most impressive effects were seen in patients with psoriatic arthritis, both for the 4 primary efficacy variables and for secondary efficacy variables such as the number of inflamed joints. Adverse events were more frequent in the SSZ group than the placebo group, but all were transient or reversible after cessation of treatment.
Conclusion: The results of this study show that SSZ had greater efficacy than placebo in the treatment of active spondylarthropathy, notably in patients with psoriatic arthritis.