A double-blind, crossover study of a sustained-release tablet of ketoprofen and normal ketoprofen capsules in the treatment of patients with osteoarthritis.

A double-blind, crossover study was carried out to assess the efficacy and tolerance of a sustained-release tablet formulation of ketoprofen given as a single daily 200 mg dose compared with 2 X 50 mg normal formulation capsules of ketoprofen twice daily. Eighty-four patients with osteoarthritis of the hip and/or knee were admitted and received treatment for periods of 3 weeks, preceded by a 1-week placebo wash-out period, with each of the two formulations, in random order. Patients were seen after each study period and clinical objective and subjective assessments made of signs and symptoms of the disease, consumption of rescue analgesic and unwanted effects. Forty-eight of the patients continued, mainly on the sustained-release formulation, in an open long-term tolerance study lasting 3 months. The results were analyzed for 68 patients who completed the double-blind phase and for 33 who completed the open phase of the study. The patients who were withdrawn did so mainly for non-drug related reasons; 19 patients did so because of gastric disorders during the first phase. The incidence of side-effects was low and similar in frequency and nature with both formulations; those that were reported were mild and principally gastro-intestinal. Both active treatment periods afforded similar symptomatic relief and were preferred to placebo by all but 2 patients. No significant differences were found between active treatments, although there was a trend in favour of the sustained-release formulation for most of the parameters studied as there was in patient preference.