To compare the gastrointestinal safety, ulcerogenic potential, and clinical efficacy over 5 years of nabumetone and naproxen therapy, in patients with rheumatoid arthritis (RA) or osteoarthritis (OA).
Fifty-two patients entered a randomized, double blind study. Patients were randomized to 3 months treatment with either nabumetone, 1000 mg nightly, or naproxen, 250 mg twice daily, followed by an endoscopist-blind 5-year followup study. After the double blind phase, 15 patients in the nabumetone group and 12 in the naproxen group continued in the longterm endoscopist-blind phase. Endoscopic evaluations for gastroduodenal damage and global assessments of arthritis activity and degree of pain for efficacy were measured.
Over the 5-year period, endoscopically visible gastroduodenal ulceration was found in 8 of the naproxen treated patients compared with one of the nabumetone treated patients (p = 0.02). There was a significant difference in the time to develop an ulcer, with a greater risk of developing an ulcer sooner while taking naproxen (p < 0.01). Patients in both groups reported significant improvements in arthritis symptoms (p < 0.01).
Nabumetone appears to have a significantly lower ulcerogenic potential than naproxen over a 5-year period, and there is a trend toward better tolerability as measured by withdrawals for adverse experiences.