A double-blind trial was carried out in 24 patients with
osteoarthritis of the knee or hip to compare the efficacy and tolerance of
oxaprozin with that of
naproxen. Patients were assigned at random to receive fixed doses of either 1200 mg
oxaprozin once daily or 250 mg
naproxen 3-times daily over a period of 8 weeks. Assessments made on entry and after 4 and 8 weeks of treatment showed that in the
oxaprozin group there were significant mean decreases, indicating improvement in patient's condition, with respect to observer's opinion, patient's opinion,
pain intensity and activity impairment at both on-
therapy visits. In the
naproxen group, there were significant mean decreases with respect to observer's opinion, patient's opinion,
pain intensity and time to walk 15 metres. None of the mean differences between the groups was statistically significant. Adverse effects were reported for 3 of the 12
oxaprozin patients and 6 of the 12
naproxen patients. The specific adverse effects noted for more than 1 patient were diarrhoea for
oxaprozin and
dyspepsia for
naproxen. No difference between the groups was statistically significant from this point of view. Laboratory determinations showed no toxicity in either group. It is concluded that once-daily
oxaprozin is an effective and well-tolerated form of treatment for
osteoarthritis, equivalent to
naproxen given 3-times daily.