Long-term efficacy and safety of auranofin: a review of clinical experience.

Auranofin (AF) is the first oral gold therapy developed for the treatment of rheumatoid arthritis (RA). Since the drug was introduced in 1982, more than 100,000 patients have been treated with AF. Controlled clinical trials prior to introduction included more than 5,000 patients, some of whom received AF for more than 7 years. At the recommended dose of 6 mg/day, AF therapy results in a lower total body burden of gold than does injectable gold (IG). However, comparative studies indicate that the clinical effect of AF is comparable to that of IG. Adverse events that occur during AF therapy tend to be mild and of short duration, often resolving with continued therapy or temporarily reduced dosage. Most adverse events occur during the first few months of therapy, and the incidence diminishes over time. Data on 134 patients who received AF for more than 5 years demonstrate a sustained therapeutic effect and no cumulative toxicity from long-term therapy. In 18 comparative trials, 1,053 patients with RA received either AF (527 patients) or IG (526 patients) for up to 36 months. At 1 year, similar proportions of patients in the AF and IG groups had 50% or greater improvement in various parameters of disease activity. Safety analysis showed that AF was significantly better tolerated than IG. The rate of withdrawal because of adverse events was about twice as great in the IG group as in the AF group, both at one year (14% vs. 31%, p less than 0.05) and for the duration of the trials (18% vs. 34%, p less than 0.05). This suggests that the benefit-to-risk ratio is more favorable with AF.