Maintenance therapy of lupus nephritis with mycophenolate or azathioprine: systematic review and meta-analysis

Objective: The objective of this study was to summarize the comparative efficacy and safety of MMF and AZA as maintenance therapy for LN.

Methods: Systematic review and meta-analysis of randomized clinical trials of MMF and AZA as maintenance therapy for LN were performed based on a sensitive search. Meta-regression was used to explore causes of heterogeneity. Safety was explored using crude and combined incidence rate ratios (IRRs) of the more frequent adverse events (AEs).

Results: The search produced 7341 hits. Four randomized clinical trials and one long-term study were selected for detailed analysis. No significant differences between MMF and AZA were found in sustained remission, relapse, renal failure, creatinine increase or death. However, there was high heterogeneity in the design of studies, drug doses and treatment in the previous induction phase. Significant lower rates of discontinuation due to AEs occurred in the MMF group, with a relative risk (RR) of 0.60 (95% CI 0.41, 0.88) but significant risk of publication bias (Egger test, P = 0.012). Gastrointestinal manifestations were more common [combined IRR 1.68 (95% CI 1.06, 2.68)] and leucopoenia less frequent in the MMF group [combined IRR 0.14 (95% CI 0.05, 0.42)].

Conclusion: The available data does not support the superiority of MMF or AZA as maintenance therapy for LN. Nevertheless, the high heterogeneity of studies included in the analysis makes this contention questionable.