Antrafenine, naproxen and placebo in osteoarthritis: a comparative study

Antrafenine is a new non-narcotic analgesic. In a double-blind, cross-over study the efficacy of antrafenine at doses of 450 mg/day and 900 mg/day was compared to naproxen 750 mg/day and placebo in patients with osteoarthritis. Each drug treatment was given for two weeks, the total duration of the study being eight consecutive weeks. Antrafenine, at either dose, was effective in relieving pain associated with osteoarthritis; the efficacy was comparable to naproxen. There was no definite indication that 900 mg/day was more effective than 450 mg/day. Antrafenine, at both dosage levels, was well tolerated. Any noted side-effects were mild. There was a total of 12 side-effects in nine patients with the high dose, five side-effects in five patients with the low dose, compared with 11 side-effects in nine patients with naproxen and 10 side-effects in seven patients with placebo.