Background/Purpose: Although intravenous cyclophosphamide (IVC) pulses are generally accepted as standard therapy for induction treatment of active proliferative lupus nephritis (LN), several clinical trials have suggested that mycophenolate mofetil (MMF) is at least as effective as IVC. The efficacy of IVC varies among racial and ethnic groups and IVC is less effective in patients of African or Hispanic descent. In contrast, MMF seems to be consistently effective in all racial/ethnic groups. Nevertheless, it is necessary to compare these two treatment modalities among different racial or ethnic groups, particularly in Asia. This study compared the efficacy of MMF and IVC as induction treatment for LN in ethnically homogeneous Korean patients.

Methods: This study enrolled 49 LN patients with available kidney biopsy specimens. Sociodemographic, clinical, laboratory, and treatment-related data at the time of kidney biopsy and during follow-up were obtained by reviewing the patients’ charts. The renal biopsy specimens were reclassified according to the ISN-RPS classification, by a renal pathologist blinded to the previous classification. The renal outcome, i.e., complete response (CR), partial response (PR), and non-response (NR), after 6 and 12 months was defined according to the ACR 2006 response criteria for proliferative and membranous renal disease in clinical trials.

Results: Of the 49 patients, 28 (57.1%) were treated with IVC and 21 (42.9%) with MMF, both in combination with prednisolone. The baseline characteristics of the two groups were comparable, except that the IVC-treated patients had lower platelet counts (p=0.026), lower C3 levels (p=0.007), and higher activity scores (p=0.021) in the renal biopsy compared to the MMF-treated patients. CR was seen in 9 of 21 patients (42.9%) receiving MMF and 14 of 28 patients (50.0%) receiving IVC after 6 months treatment (p= 0.450) and in 11 of 21 patients (52.4%) in the MMF group and 13 of 28 patients (46.4%) in the IVC group at 1 year (p= 0.745). The number of patients achieving PR and NR did not differ significantly at 6 and 12 months between the treatment groups.

Conclusion: These findings suggest that the efficacy of oral MMF at 1 year does not differ from that of IVC in induction treatment of LN in ethnically homogeneous Korean patients. MMF may be considered first-line induction therapy for treating LN in these patients.

ACR Meeting Abstracts - https://acrabstracts.org/abstract/comparison-of-mycophenolate-mofetil-and-intravenous-cyclophosphamide-as-induction-therapy-in-korean-patients-with-lupus-nephritis/