Efficacy and safety of single-dose mizoribine for patients with rheumatoid arthritis: results at 6 months after switching from a multiple-dose regimen without a change in total daily dose

Abstract

To determine the efficacy and safety of single-dose mizoribine (MZR) for patients with rheumatoid arthritis (RA), a 6-month, single-arm, open-label, prospective observation study was performed. In patients who had been taking MZR at 100-150 mg/day in 2-3 divided portions continuously for at least 3 months, and who had shown a lack of clinical response, or escape (defined as a lack of response at the time of switching, even if some form of response had been shown before that), multiple-dose administration was switched to single-dose administration without changing the total daily dose. Efficacy was assessed in terms of the disease activity score, using the 28-joint count and erythrocyte sedimentation rate (DAS 28-ESR). Of the 34 enrolled patients, 28 met all the eligibility criteria and were assessed for efficacy, and finally 26 patients were able to receive the single-dose regimen throughout the full 6 months. The DAS28-ESR showed a significant decrease from 2 months after switching, and 46.4% of the 28 patients finally achieved a good or moderate response (3 and 10 patients, respectively). With regard to safety, no serious adverse events were observed. In conclusion, the administration of MZR at 100 or 150 mg in a single dose is thought to be a useful alternative form of MZR therapy.

Mizoribine is as Effective as Methotrexate for the Treatment of Polymyalgia Rheumatica: A Retrospective Case Series Analysis

“…MZR was approved by the Japanese Ministry of Health, Labour and Welfare in 1984. Since then, MZR has been widely used in Japan for renal transplantation and rheumatic diseases, including RA [10][11][12] and SLE. [13][14][15] Nomura et al 13 reported that 12 patients with SLE were successfully treated with glucocorticoid, MZR and tacrolimus.…”

“…23 Compared to these agents, MZR's strong point is its safety. MZR can be safely used for elderly people, 11,12,15 and therefore, is a promising agent in the treatment of PMR.…”

“…8 MZR has a less serious side effect profile and contraindications compared to MTX and can be safely used for patients with lung disease or chronic kidney disease, although it sometimes causes side effects including infections, hyperuricemia, anemia, and elevation in liver enzymes. 9 MZR has already been used effectively in clinical practice for the treatment of rheumatoid arthritis (RA), [10][11][12] systemic lupus erythematosus (SLE), [13][14][15] kidney transplantation, 16 nephrotic syndrome, 9 and immunoglobulin A nephropathy 17 in Japan. However, the role of MZR in the treatment of PMR has not been clarified.…”