Randomized comparative trial of mizoribine versus mycophenolate mofetil in combination with tacrolimus for living donor renal transplantation

Mizoribine Promotes Molecular Chaperone HSP60/HSP10 Complex Formation

It has been reported that Mizoribine is an immunosuppressant used to suppress rejection in renal transplantation, nephrotic syndrome, lupus nephritis, and rheumatoid arthritis. The molecular chaperone HSP60 alone induces inflammatory cytokine IL-6 and the co-chaperone HSP10 alone inhibits IL-6 induction. HSP60 and HSP10 form a complex in the presence of ATP. We analyzed the effects of Mizoribine, which is structurally similar to ATP, on the structure and physiological functions of HSP60-HSP10 using Native/PAGE and transmission electron microscopy. At low concentrations of Mizoribine, no complex formation of HSP60-HSP10 was observed, nor was the expression of IL-6 affected. On the other hand, high concentrations of Mizoribine promoted HSP60-HSP10 complex formation and consequently suppressed IL-6 expression. Here, we propose a novel mechanism of immunosuppressive action of Mizoribine.

Immunosuppressive Agent Options for Primary Nephrotic Syndrome: A Review of Network Meta-Analyses and Cost-Effectiveness Analysis

Therapeutic options with immunosuppressive agents for glomerular diseases have widened with refinements to the Kidney Disease Improving Global Outcomes (KDIGO) guidelines from 2012 to 2021. However, international guidelines do not necessarily match the reality in each country. Expensive therapies such as rituximab and calcineurin inhibitors are sometimes inaccessible to patients with refractory nephrotic syndrome due to cost or regulations. Under the Japanese medical insurance system, rituximab is accessible but still limited to steroid-dependent patients who developed idiopathic nephrotic syndrome in childhood. Based on international KDIGO guidelines and other national guidelines, possible applications of immunosuppressive agents for nephrotic syndrome are comprehensively examined in this review. While rituximab has become the mainstay of immunosuppressive therapy for nephrotic syndrome, clinical trials have indicated that options such as cyclophosphamide, calcineurin inhibitors, and mycophenolate mofetil would be preferable. Given the rising number of patients with nephrotic syndrome worldwide, KDIGO guidelines mention the need for further consideration of cost-effectiveness. If the new option of rituximab is to be the first choice in combination with steroids for nephrotic syndrome, its cost-effectiveness should also be verified. Among the few studies examining the cost-effectiveness of treatments for nephrotic syndrome, administration of rituximab to young adults has been shown to be cost-beneficial, at least in Japan. However, further large-scale studies involving multiple facilities are needed to verify such findings. Network meta-analyses have concluded that the efficacy of rituximab remains controversial and confirmation through high-quality studies of large cohorts is needed. To this end, the mechanisms of action underlying immunosuppressive agents, both old and new, need to be understood and experience must be accumulated to evaluate possible effects and side effects.

The Efficacy and Safety of Mizoribine versus Mycophenolate Mofetil for the Treatment of Renal Transplantation: A Systematic Review and Meta-Analysis

Background

Mizoribine (MZR) is widely used in Asia due to its high safety and low cost, and comparative studies of its safety and efficacy with the first-line drug mycophenolate mofetil (MMF) have been carried out. This paper aimed to compare the efficacy and safety of MZR and MMF in immunosuppressive therapy of renal transplantation by meta-analysis.

Methods

We searched randomized controlled trials (RCTs) comparing MZR versus MMF for renal transplantation in PubMed, Excerpta Medica Database (EMBASE), Cochrane Library, Web of Science, WanFang Database, China National Knowledge Infrastructure (CNKI), and Chinese Biomedical Database (CBM). Articles were assessed for their risk of bias using the Cochrane Collaboration. Forest plots and funnel plots were also performed on the included articles.

Results

A total of twelve studies with 1103 patients were selected in the analysis. No significant difference were observed between the MZR group and the MMF group for the rate of acute rejection (RR = 1.50, 95% CI 1.11 to 2.01, P = 0.008), patient survival (RR = 1.01, 95% CI 0.99 to 1.03, P = 0.56), graft survival (RR = 1.02, 95% CI 1.00 to 1.04, P = 0.12), leucopenia (RR = 0.69, 95% CI 0.44 to 1.10, P = 0.12), and liver damage (RR = 0.72, 95% CI 0.46 to 1.13, P = 0.15). The MZR group was associated with a lower risk of gastrointestinal disorder (RR = 0.28, 95% CI 0.13 to 0.62, P = 0.002) and cytomegalovirus infection (RR = 0.59, 95% CI 0.42 to 0.84, P = 0.003) but had a higher risk of hyperuricemia (RR 1.79, 95% CI 1.17 to 2.75, P = 0.007). No significant publication bias was observed among included studies. Discussion. MZR is similar to MMF in efficacy, and in terms of safety, MZR has a lower risk of gastrointestinal disorder and cytomegalovirus infection but a higher risk of hyperuricemia.

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

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.

Hyperuricemia in Living Donor Kidney Transplantation Patients During Mizoribine Administration Caused Mainly by Changes in Kidney Function

BACKGROUND

Although mizoribine (MZR) is used as an immunosuppressant after renal transplantation, the occurrence of hyperuricemia has been reported. The onset of hyperuricemia is often observed within the first several months after surgery. Since MZR is a renal excretion-type drug excreted as an unchanged drug from the kidneys, MZR blood concentrations may rise due to the influence of renal function. We investigated whether the onset of hyperuricemia after MZR administration was associated with the direct effect of a change in renal function.

METHODS

Serum uric acid (serum UA), serum creatinine (sCr), serum β2-microglobulin (serum β2-MG), and serum cystatin C (serum Cys-C) were measured for about 3 months in 22 subjects. Correlation coefficients were calculated using the change rates of serum UA and sCr (Δ serum UA, Δ sCr), serum UA and serum β2-MG (Δ serum UA, Δ serum β2-MG), and serum UA and serum Cys-C (Δ serum UA, Δ serum Cys-C) at the onset of hyperuricemia.

RESULTS

The correlation coefficients between Δ serum UA and Δ sCr, Δ serum UA and Δ serum β2-MG, and Δ serum UA and Δ serum Cys-C were 0.723 (P < .001), 0.863 (P < .001) and 0.548 (P < .001), respectively. Further, serum UA and sCr level reached their highest peak on the same day after MZR administration, and the behavior was mostly consistent.

CONCLUSION

It was suggested that hyperuricemia occurred about 3 months after MZR administration due mainly to temporary changes in kidney function.

Beneficial Effects of High-Dose Mizoribine on ABO-Incompatible Living-Related Kidney Transplantation: Two-Year Results by a Japanese Multicenter Study

BACKGROUND

Mizoribine (MZ) has been developed as an immunosuppressive agent in Japan, but it has a less-potent immunosuppressive effect up to 3 mg/kg/d. In the previous study, a Japanese multicenter study, we reported that high-dose MZ, at 6 mg/kg/d, with a calcineurin inhibitor was effective and safe in reducing the frequency of cytomegalovirus (CMV)-related events in ABO-incompatible (ABO-i) living-related kidney transplantation (LKT). In the present study, therefore, we investigated the effects of high-dose MZ with a CNI in ABO-i LKT recipients in a Japanese multicenter study.

METHODS

A total of 37 patients were treated with high-dose MZ (6 mg/kg), a CNI (cyclosporine [CsA] or tacrolimus [Tac]), basiliximab (Bas), rituximab (Rit), and corticosteroids. CsA was started at a dose of 7 mg/kg to maintain blood levels [200 ng/mL (C0), 6000 ng-h/mL (AUC 0-9)]. Tac was started at a dose of 0.2 mg/kg to maintain blood levels [8-10 ng/mL (C0), 100 ng-h/mL (AUC 0-9)]. Bas (20 mg/body) was administrated on day 0 and day 4 after transplantation. Rit (100-200 mg/body) was administrated on day -14 and day -7 before transplantation. MZ was adjusted to maintain target C0 levels of 1.5 to 2.0 μg/mL.

RESULTS

Patient and graft survival rates for 2 years were 100% in the CsA group (n = 22) and 93.3% in the Tac group (n = 15) (not significant, NS). Overall incidence of acute rejection for 2 years was 22.7% in the CsA group and 26.7% in the Tac group. Mean serum creatinine levels at 2 years were 1.29 ± 0.2 mg/dL in the CsA group and 1.21 ± 0.34 mg/dL in the Tac group (NS). The incidence of CMV disease was 0% in both groups, and positive rates of CMV antigenemia were 50.0% and 26.7% in the CsA and Tac groups, respectively (NS). Mean serum uric acid levels were 5.5 ± 1.3 mg/dL and 6.4 ± 1.2 mg/dL at 2 years (NS) in the CsA and Tac groups, respectively.

CONCLUSIONS

A high-dose MZ regimen including calcineurin inhibitor (CsA or Tac), Bas, Rit, and steroids was effective and safe in reducing the frequency of CMV-related events in ABO-i LKT.

High-dose mizoribine combined with calcineurin inhibitor (cyclosporine or tacrolimus), basiliximab and corticosteroids for renal transplantation: A Japanese multicenter study

OBJECTIVE

To evaluate the utility and safety of high-dose mizoribine combination therapy using cyclosporine and tacrolimus as calcineurin inhibitors in patients undergoing kidney transplant.

METHODS

The present study enrolled 156 patients who received kidney transplants in 18 institutions between 2009 and 2013. ABO-incompatible and/or pre-sensitized recipients were excluded. Immunosuppression used cyclosporine (88) or tacrolimus (68) as a calcineurin inhibitor, and the dosage was adjusted based on blood concentrations. Mizoribine was started at 6 mg/kg/day, and the target trough level was 1-2 ng/mL. Primary efficacy end-points of this study were 2-year patient survival, 2-year graft survival and the acute rejection rate within 2 years after transplantation.

RESULTS

The 2-year patient and graft survival rates in the cyclosporine group were 98.9% and 94.3%, respectively, whereas those in the tacrolimus group were 100% and 98.5%, respectively, with no significant difference between groups. Rates of onset of rejection during the observation period were also equivalent, at 22.7% in the cyclosporine group and 17.6% in the tacrolimus group. Furthermore, groups showed no significant differences in transplanted renal function. No notable differences in adverse events were observed between groups.

CONCLUSIONS

A regimen of high-dose mizoribine in combination with calcineurin inhibitors basiliximab, and corticosteroids can provide effective immunosuppression while lowering the rate of cytomegalovirus infection in kidney transplant patients.

Mizoribine therapy combined with steroids and mizoribine blood concentration monitoring for idiopathic membranous nephropathy with steroid-resistant nephrotic syndrome

Background

We designed a prospective and randomized trial of mizoribine (MZR) therapy combined with prednisolone (PSL) for idiopathic membranous nephropathy (IMN) with steroid-resistant nephrotic syndrome (SRNS).

Methods

Patients with IMN were divided into 2 groups, and MZR combined with PSL was administered for 2 years. PSL was initially prescribed at 40 mg/day and tapered. MZR was given once-a-day at 150 mg and 3-times-a-day at 50 mg each to groups 1 and 2. Serum MZR concentrations from 0 to 4 h after administration were examined within one month of treatment. The concentration curve and peak serum level (C_max) of MZR were estimated by the population pharmacokinetic (PPK) parameters of MZR.

Results

At 2 years, 10 of 19 patients (52.6 %) in group 1 and 7 of 18 patients (38.9 %) in group 2 achieved complete remission (CR). The time-to-remission curve using the Kaplan–Meier technique revealed an increase in the cumulative CR rate in group 1, but no significant difference between the groups. Meanwhile, there was a significant difference in C_max between groups 1 and 2 (mean ± SD: 1.20 ± 0.52 vs. 0.76 ± 0.39 μg/mL, p = 0.04), and C_max levels in CR cases were significantly higher than those in non-CR cases. Receiver operating characteristic analysis showed that C_max more than 1.1 µg/mL was necessary for CR in once-a-day administration.

Conclusion

Administration of MZR once a day is useful when combined with PSL for treatment of IMN with SRNS. In addition, it is important to assay the serum concentration of MZR and to determine C_max, and more than 1.1 µg/mL of C_max is necessary for CR.

A Prospective Randomized, Comparative Trial of High-Dose Mizoribine Versus Mycophenolate Mofetil in Combination With Tacrolimus and Basiliximab for Living Donor Renal Transplant: A Multicenter Trial

OBJECTIVES

Our objectives were to compare the clinical outcomes of mizoribine (12 mg/kg/d) and mycophenolate mofetil (2000 mg/d) in combination with tacrolimus, basiliximab, and corticosteroids.

MATERIALS AND METHODS

We enrolled 83 recipients of living-donor renal transplant (performed between 2008 and 2013) in this study. This prospective multi-institutional randomized comparative study compared mizoribine (n = 41) and mycophenolate mofetil (n = 42) in combination with tacrolimus, basiliximab, and corticosteroids for living-donor renal transplant recipients. We compared the acute rejection and graft survival rates and adverse event rates within 1 year of renal transplant between the 2 groups using intention-to-treat analyses.

RESULTS

During the 1-year observation period, patient and graft survival rates were 100%. The acute rejection rate was 17.1% in the mizoribine group and 19% in the mycophenolate mofetil group. The incidence rate of cytomegalovirus infection seropositivity (recipient and donor with positive cytomegalovirus antibody status) was higher in the mycophenolate mofetil group than in the mizoribine group, although the difference in these rates was not statistically significant. The incidence of leukopenia was higher in the mizoribine group than in the mycophenolate mofetil group.

CONCLUSIONS

High-dose mizoribine at 12 mg/kg/day was a safe and efficacious immunosuppressive alternative to mycophenolate mofetil in living-donor renal transplant recipients. Leukopenia should be closely monitored in the initial period of insufficient kidney function after renal transplant.

A four-drug combination therapy consisting of low-dose tacrolimus, low-dose mycophenolate mofetil, corticosteroids, and mizoribine in living donor renal transplantation: A randomized study

OBJECTIVE

We compared a three-drug combination therapy (control group) consisting of tacrolimus, mycophenolate mofetil, and corticosteroids in living donor renal transplantation with a four-drug combination therapy (study group), in which the doses of tacrolimus and mycophenolate mofetil were halved and the immunosuppressive drug mizoribine was added, in order to determine whether the incidence rates of acute rejection after transplantation between the study group and the control group are similar, whether the study group regimen prevents the occurrence of calcineurin inhibitor-induced renal damage, and whether the study group regimen prevents adverse effects such as diarrhea caused by mycophenolate mofetil.

METHODS

We investigated the incidence of acute rejection, serum creatinine levels, and estimated glomerular filtration rate and the incidence of adverse effects such as diarrhea.

RESULTS

There was no significant difference between the two groups in the incidence of acute rejection. Renal function (estimated glomerular filtration rate and serum creatinine) was maintained in the control group whereas in the study group renal function gradually improved, with a statistical difference observed at 12 months. The incidence of gastrointestinal symptoms including diarrhea was significantly higher in the control group than in the study group. There was no significant difference in the incidence of cytomegalovirus infection and other adverse effects.

CONCLUSION

These results suggest the study group therapy is an effective regimen in preventing acute rejection and the deterioration of renal function. These results also show this therapy can reduce the incidence of adverse effects such as gastrointestinal symptoms.

Improvement in Severe Mycophenolic Acid-associated Gastrointestinal Symptoms after Changing Enteric-coated Mycophenolate Sodium to Mizoribine in Renal Transplant Recipients: Two Case Reports

Clinical results point to a better gastrointestinal tolerability with enteric-coated mycophenolate sodium as compared to mycophenolate mofetil. However, some transplant recipients who are treated with enteric-coated mycophenolate sodium still experience gastrointestinal symptoms. We herein present two cases of renal transplant recipients with severe gastrointestinal symptoms who were switched from enteric-coated mycophenolate sodium to mizoribine, and the symptom reversal effects were evaluated using the Gastrointestinal Symptom Rating Scale. The results of this study showed a significant improvement in severe gastrointestinal symptoms in renal transplant recipients after converting from enteric-coated mycophenolate sodium to mizoribine.

Long-term post-marketing surveillance of mizoribine for the treatment of lupus nephritis: Safety and efficacy during a 3-year follow-up

OBJECTIVE

To determine the safety and efficacy of long-term use of mizoribine by undertaking a 3-year post-marketing surveillance study.

METHODS

Subjects were all lupus nephritis patients newly treated with mizoribine between 1 October 2003 and 30 September 2005 at contracted study sites.

RESULTS

Mizoribine was administered to 881 lupus nephritis patients in the safety analysis set consisting of 946 patients recruited from 281 contracted study sites after satisfying the eligibility criteria. There were 301 events of adverse drug reactions that were observed in 196 (20.7%) of the 946 subjects. There were 34 events of serious adverse drug reactions in 31 patients (3.2%). No deterioration in hematological and biochemical test values was observed, but immunological testing showed significant improvements in C3, CH50, and anti-DNA antibody titers. The negative rate of proteinuria also increased over time. The median steroid dosage was 15 mg/day at the commencement of treatment, but was reduced to 10 mg/day at 12 months and 8 mg/day at 36 months.

CONCLUSION

The findings of the 3-year long-term drug use surveillance study indicated that mizoribine can be used over the long term with relatively few adverse drug reactions, suggesting its suitability for use in maintenance drug therapy.

Comparative efficacy and safety of mizoribine with mycophenolate mofetil for Asian renal transplantation--a meta-analysis

OBJECTIVES

Mizoribine (MZR) with its high safety and low cost has been widely used in Asia. It has been questioned whether high or low dose of MZR could obtain the efficacy and safety similar to mycophenolate mofetil (MMF) following renal transplantation. This meta-analysis was done to compare the efficacy and safety of high- or low-dose MZR with MMF for immunosuppressive therapy in renal transplantation.

DESIGN AND METHODS

Available data comparing MZR with MMF in renal transplant recipients were searched. Subgroup analysis was conducted according to the administration dosage of MZR. Trials were pooled using Meta-analysis software and confidence intervals were set at 95%.

RESULTS

Altogether 1149 Asian patients from 7 RCTs and 9 cohort studies were included. The efficacy of different MZR doses put on par with MMF, but the safety was better than MMF. Specifically, recipients taking MZR favor significantly fewer episodes of leucocytopenia [RR 0.40 (0.26, 0.60)], gastrointestinal disorder [RR 0.54 (0.40, 0.73)], CMV infection [RR 0.47 (0.34, 0.64)] and more favorable outcome of hepatic dysfunction, although the difference failed to reach a statistical significance [RR 0.67 (0.44, 1.00)]. Unfortunately, hyperuricemia was significantly obvious in MZR group [RR 1.96 (1.47, 2.61)].

CONCLUSIONS

MZR is an effective and safe immunosuppressive agent and high-dose MZR can be recommended as an alternative to MMF following adult renal transplantation in Asia, but hyperuricemia and liver damage should be closely monitored during the medication period.

Mizoribine versus mycophenolate mofetil in combination therapy with tacrolimus for de novo kidney transplantation: evaluation of efficacy and safety

The present study compared the efficacy and safety of mizoribine (MZR) with mycophenolate mofetil (MMF) in kidney transplantation. This multicenter, randomized clinical trial. Employed doses of study drug tailored to the immunosuppressive need. The primary efficacy outcome was the incidence of biopsy-proven acute rejection episodes (BPAR). The safety of the study drug was assessed using the incidences of adverse events, drug discontinuations, and abnormal laboratory results. The 7 (6.4%) BPARs above grade II were observed in the MZR group noninferior to the 2 (1.8%) in the MMF group (95% confidence interval, -0.007-0.097 > noninferiority limit [-0.2]). BPAR was significantly decreased in the MZR group after the dose change (17/41 [41.4%] vs 8/69 [11.6%]; P < .0001) and the incidence of BPAR was similar between the MZR and MMF groups after the dose change (P = .592). The uric acid level was significantly elevated in the MZR group (P = .002). In conclusion, the efficacy and safety of MZR were similar and statistically noninferior to MMF in combination therapy with tacrolimus.