Objective: For reasons of insufficient quality of the raw material, aurothioglucose was withdrawn from the Dutch market at the end of 2001. Aurothiomalate became available as an alternative preparation. We followed a cohort of patients during the first year after switching from aurothioglucose to aurothiomalate to study efficacy and tolerability.
Methods: Patients were observed at baseline and at 3 and 12 months after switching. At each visit, data on adverse drug reactions (ADR), withdrawal, and disease activity were collected.
Results: In total 120 patients were included [age 63(SD 15) yrs, 68% female, 93% with rheumatoid arthritis, duration of disease 15 (SD 9) years, 82% IgM rheumatoid factor-positive, with 9 (SD 9, range 0.1-45) yrs of previous aurothioglucose therapy]. Nineteen patients (16%) reported an ADR taking aurothiomalate not previously experienced with aurothioglucose, the most frequently reported being pruritus, dermatitis/stomatitis, and chrysiasis/hyperpigmentation. Twenty-nine patients (24%) withdrew from aurothiomalate within 12 months of followup for reasons of inefficacy (14%), ADR (7%), or disease in state of remission (3%). Kaplan-Meier estimates show aurothiomalate survival rates of 78.5% after 12 months. No statistically significant differences between the disease activity indicators during followup visits compared with the baseline visit were detected for the patients continuing aurothiomalate.
Conclusion: Within the first 12 months after switching from aurothioglucose, 24% of patients withdrew from aurothiomalate. Sixteen percent of patients reported novel ADR. For the population continuing to take aurothiomalate no clinically relevant changes in disease activity were recorded after switching.