Gastroduodenal tolerability of nabumetone versus naproxen in the treatment of rheumatic patients.

Objective: The objective of this endoscopic, double-blind study was to evaluate the gastric tolerability of nabumetone, a novel nonsteroidal anti-inflammatory drug, compared with naproxen in patients with rheumatoid arthritis.
Methods: Patients with definite or classic rheumatoid arthritis as defined by ACR criteria were eligible for entry into the study if an initial endoscopy was normal or showed the presence of only one erosion or one or two submucosal hemorrhages. After a 7-day washout period, the patients were randomized to receive either nabumetone, 1 g, or naproxen, 500 mg, b.i.d. Blinding was achieved by the use of double dummies. Endoscopy was repeated after 4 wk of treatment. The primary efficacy parameters were Ritchie articular index, duration of morning stiffness, and global assessments.
Results: Gastric mucosal lesions of different degrees were observed in 9% (2/22) of nabumetone-treated patients and in 40% (12/30) of those who received naproxen (p = 0.01). One duodenal ulcer was found in a patient treated with nabumetone, and this patient had a history of duodenal ulcer. In the naproxen group, six patients were found to have an ulcer. Clinical evaluation of rheumatological symptomatology showed no statistical difference in relieving symptoms between the two drugs in the primary efficacy assessments. However, six nabumetone-treated patients dropped out because of lack of efficacy, compared with one in the naproxen group. Side effects were noted in three patients treated with nabumetone and in 14 treated with naproxen (p = 0.004).
Conclusion: This study showed that nabumetone, 1 g daily, results in significantly less deterioration of gastric mucosa than naproxen, 500 mg daily, but the efficacy of naproxen, 1 g, appears to be more than that achieved with nabumetone, 1 g.