Nabumetone in the treatment of active adult rheumatoid arthritis.

One hundred patients were entered in a six-month, double-blind comparison of 1,000 mg nabumetone once daily and 250 mg naproxen twice daily. Forty-two patients in each arm of the study were evaluable for efficacy; all were evaluable for safety. There was a low incidence of adverse experiences during this study, with no patients withdrawing from the study because of side effects from either drug. Efficacy was equal, with both compounds sharing the same degree and rate of improvement. All of the patients completing the double-blind phase were then switched to open-label treatment with nabumetone. The dosage of nabumetone was gradually increased. At the end of one year, 84 patients remained in the study (52 taking 1,000 mg per day, 23 taking 1,500 mg, and nine taking 2,000 mg). This gradual increase has continued, and, at this time, 61 patients remain in the study (seven taking 1,000 mg per day, 24 taking 1,500 mg, and 30 taking 2,000 mg). There have been very few side effects. From this study, it can be concluded that nabumetone is at least as effective as naproxen and, even at higher doses, had an acceptable safety profile for extended use in patients with rheumatoid arthritis.