The objective was to compare the safety and efficacy of methotrexate (MTX) and gold sodium thiomalate (GSTM) in patients with early erosive rheumatoid arthritis (RA). A total of 174 patients with active early erosive RA without deformities were enrolled in a 12 month, two-centre double-blind randomized trial. They received a weekly i.m. dose of 15 mg MTX (n = 87) or 50 mg GSTM (n = 87), respectively. Clinical and laboratory evaluations were carried out every 3 months in all patients, including the withdrawals. Ten patients (11.5%) in the MTX group and 21 patients (24.1%) in the GSTM group achieved a clinical remission of the disease [no swollen joints, erythrocyte sedimentation rate (ESR) < 20 mm, no steroids] within the study period (P < 0.05). An at least marked improvement (> 50% reduction of the number of swollen and tender joints and the ESR) was assessed in 59/87 (68%) and 66/87 (76%) patients treated with MTX or GSTM, respectively (P > 0.05). Significantly more patients in the GSTM group were withdrawn due to toxicity (six MTX/32 GSTM). A total of 126 patients (73 on MTX and 53 on GSTM) completed 12 months on their original medication. In the completers, a significant improvement of > 50% compared to baseline was noted in all six clinical variables [morning stiffness, joint count of swollen and tender joints, Lansbury index, grip strength and activities of daily living (ADL) score], the ESR and the C-reactive protein, without intergroup differences. The number of patients taking prednisone was reduced from 21 to 7% in the MTX group and from 15 to 4% in the GSTM group. While significantly more patients achieved a clinical remission with GSTM treatment, tolerability was significantly better with MTX.