Comparative efficacy and safety of mizoribine and mycophenolate mofetil for treating systemic lupus erythematosus: a retrospective cohort study

Masahiro Ayano; Yasutaka Kimoto; Hiroki Mitoma; Mitsuteru Akahoshi; Nobuyuki Ono; Yojiro Arinobu; Koichi Akashi; Takahiko Horiuchi; Hiroaki Niiro

doi:10.1177/1759720X221096367

Comparative efficacy and safety of mizoribine and mycophenolate mofetil for treating systemic lupus erythematosus: a retrospective cohort study

Ther Adv Musculoskelet Dis. 2022 May 13:14:1759720X221096367. doi: 10.1177/1759720X221096367. eCollection 2022.

Authors

Masahiro Ayano¹, Yasutaka Kimoto², Hiroki Mitoma³, Mitsuteru Akahoshi³, Nobuyuki Ono³, Yojiro Arinobu³, Koichi Akashi³, Takahiko Horiuchi², Hiroaki Niiro⁴

Affiliations

¹ Department of Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
² Department of Internal Medicine, Kyushu University Beppu Hospital, Beppu, Japan.
³ Department of Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
⁴ Department of Medical Education, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.

Abstract

Background: Mizoribine (MZR) is an immunosuppressive agent that selectively inhibits inosine monophosphate dehydrogenase; its actions are considerably similar to those of mycophenolate mofetil (MMF). This study aimed to clarify whether MZR can be a good treatment option for systemic lupus erythematosus (SLE) and to compare the efficacy and safety of MZR and MMF in patients with active SLE.

Methods: We retrospectively compared the efficacy, continuation rate, and safety of MZR (52 patients) and MMF (31 patients) after adjusting for stabilized inverse probability of treatment weighting based on propensity scores. The efficacy endpoints were as follows: cumulative incidence of lupus low disease activity state (LLDAS) or remission attainment and flares and change in prednisolone dose over 2 years. Drug continuation rates were defined as the time from drug initiation to discontinuation for any cause, owing to the lack of efficacy, or owing to adverse events. The safety endpoint was the frequency of adverse events.

Results: Overall, 25 (48.1%) and 13 (25.0%) patients in the MZR group and 18 (58.1%) and 15 (48.3%) in the MMF group achieved LLDAS and remission during the follow-up period, respectively; thus, the cumulative incidence of LLDAS and remission attainment of the two groups was similar after adjustment. Prednisolone dose was steadily reduced in both the groups, and the change in prednisolone dose was nearly identical between the two groups. Drug discontinuation rate due to adverse events and the frequency of all adverse events and infections were higher in the MMF group than in the MZR group, albeit without significance after adjustment.

Conclusion: MZR is as effective as MMF in controlling SLE activity. The adverse events of MZR, whose profile differs from MMF, are comparable to or less than those of MMF. MZR may be a valuable option as an immunosuppressive agent for SLE, as well as MMF.

Keywords: continuation rate; lupus low disease activity; mizoribine; mycophenolate mofetil; systemic lupus erythematosus.