Efficacy and Safety of Mizoribine in the Treatment of Lupus Nephritis: A Systematic Review and Meta-Analysis.

INTRODUCTION

This study evalöuated the clinical efficacy and safety of mizoribine (MZR) in the treatment of lupus nephritis.

METHODS

We conducted a systematic review and meta-analysis in accordance with PRISMA 2020 guidelines. Literature searches were performed in PubMed, Embase, Web of Science, Cochrane Library, and ClinicalTrials.gov up to June 30, 2025. Two investigators independently screened studies, extracted data, and assessed risk of bias. Included studies enrolled patients with biopsy-confirmed lupus nephritis treated with mizoribine-containing regimens, including randomized controlled trials (RCTs), cohort studies, and single-arm designs. Primary and secondary outcomes were renal response rate (The proportion of patients achieving either complete response (CR) and partial response (PR). CR: 24-h urinary protein < 0.5 g/day with normal/stable serum creatinine ≤ 25%. PR: ≥ 50% reduction in proteinuria to < 3.5 g/day with stable serum creatinine ≤ 25%), and adverse reaction rate, 24-h urinary protein, and systemic lupus erythematosus disease activity index (SLEDAI) score, respectively. Data were analyzed in STATA 14.0 using fixed or random-effects models based on heterogeneity (random effects for I2 ≥ 25% and P ≤ 0.1). Prespecified subgroup analyses were performed by treatment duration (induction period ≤ 6 months vs. maintenance period > 6 months) and control regimen (glucocorticoid group vs. glucocorticoid and immunosuppressants ).

RESULTS

Nineteen studies (four RCTs, one cohort, 14 single-arm) with 1489 patients were included. Meta-analysis of randomized controlled trials (RCTs) showed no significant differences in renal response rates or adverse reaction rates between MZR and control groups, but a higher SLEDAI score was observed with MZR (WMD = 1.75, 95% CI 0.33-3.16, P < 0.05). Subgroup analysis indicated MZR was associated with a reduced renal response rates (RR = 0.83, 95% CI 0.71-0.97, P < 0.05), elevated proteinuria (WMD = 0.62, 95% CI 0.22-1.03, P < 0.05), and higher SLEDAI scores (WMD = 1.75, 95% CI 0.33-3.16, P < 0.05) versus controls. These negative outcomes, including increased proteinuria (WMD = 0.73, 95% CI 0.11-1.36, P < 0.05) and SLEDAI (WMD = 2.60, 95% CI 1.19-4.01, P < 0.05), were significant only in the induction period use (P < 0.05) and not sustained maintenance period (> 6 months). Single-arm studies reported high response rates (59-100%) but widely variable adverse reaction rates (5-50%). The types of adverse events included hyperuricemia, respiratory tract infection, leukopenia, etc.

CONCLUSIONS

Mizoribine demonstrates phased efficacy in lupus nephritis: it is less effective than standard regimens for the induction period (≤ 6 months) but comparable during the maintenance period (> 6 months). Therefore, it is not a first-line induction agent but serves as a practical maintenance option, particularly for patients intolerant of conventional therapies or in resource-limited settings.