Use of mycophenolate mofetil in resistant membranous nephropathy

Multitarget therapy with a corticosteroid, cyclosporine and mycophenolate mofetil for idiopathic membranous nephropathy: a prospective randomized controlled trial

BACKGROUND

The effectiveness of multitarget combination therapy with a corticosteroid, cyclosporine and mycophenolate mofetil for idiopathic membranous nephropathy (IMN) is unclear. In the present study, we aimed to compare the efficacy and safety of multitarget therapy with a cyclical corticosteroid-cyclophosphamide regimen in patients with IMN.

METHODS

This was a single-centre, prospective, randomized, controlled trial. We randomly assigned patients with IMN to receive multitarget therapy (a combination of prednisone, cyclosporine and mycophenolate mofetil) or 6-month cyclical treatment with a corticosteroid and cyclophosphamide. The study patients were followed up for 12 months. The primary outcome was a composite of complete or partial remissions at 12 months. Adverse events were also assessed.

RESULTS

The study cohort comprised 78 patients, 39 of whom received multitarget therapy and the other 39 cyclical alternating treatment with a corticosteroid and cyclophosphamide. At 12 months, 31 of 39 patients (79%) in the multitarget therapy group and 34 of 39 (87%) in the corticosteroid-cyclophosphamide group had achieved complete or partial remissions (relative risk 0.93; 95% confidence interval 0.72-1.21; P = .85; log-rank test). The prevalence of adverse events was significantly lower in the multitarget therapy group than in the corticosteroid-cyclophosphamide group [46% (18 of 39) vs 74% (29 of 39); P < .05].

CONCLUSIONS

Multitarget therapy for IMN patients is noninferior to cyclical alternating treatment with corticosteroid and cyclophosphamide in inducing proteinuria remission and has a better safety profile than the corticosteroid-cyclophosphamide combination.

C5b-9 Glomerular Deposits Are Associated With Poor Renal Survival in Membranous Nephropathy

Introduction

Membranous nephropathy (MN) is the first cause of nephrotic syndrome in patients without diabetes. Its prognosis is variable, and treatment remains controversial because of potential toxicity. Currently, there is no reliable prognostic marker common to all etiologies of MN and routinely available to predict the disease course and guide therapeutic management. Despite the major role of complement in the glomerular damage of MN, its prognostic impact has never been studied. We investigated the frequency and prognostic impact of glomerular deposition of C5b-9 in MN.

Methods

We retrospectively selected adults diagnosed with MN (primary or secondary) at Montpellier University Hospital between December 2004 and December 2015. To be included, all patients were required to have complete medical data and a kidney tissue sample for further immunohistochemistry. We performed PLA2R1, C4d, and C5b-9 staining by immunohistochemistry.

Results

Sixty-four adults were included: 45 with primary MN and 19 with secondary MN. C4d was positive in the glomeruli of 61 adults (95.3%). Twenty-nine adults (45.3%) had glomerular deposition of C5b-9. Patients with glomerular deposition of C5b-9 had more severe nephrotic syndrome on diagnosis and lower remission and renal survival rates than adults without.

Conclusion

C5b-9 glomerular staining is a powerful and easily accessible tool for stratifying adults according to their renal prognosis. The efficacy of complement inhibitors should be tested in adults with glomerular deposition of C5b-9.

Advances in the Management of Primary Membranous Nephropathy and Rituximab-Refractory Membranous Nephropathy

Primary membranous nephropathy (pMN) is an auto-immune disease characterized by auto-antibodies targeting podocyte antigens resulting in activation of complement and damage to the glomerular basement membrane. pMN is the most common cause of nephrotic syndrome in adults without diabetes. Despite a very heterogeneous course of the disease, the treatment of pMN has for many years been based on uniform management of all patients regardless of the severity of the disease. The identification of prognostic markers has radically changed the vision of pMN and allowed KDIGO guidelines to evolve in 2021 towards a more personalized management based on the assessment of the risk of progressive loss of kidney function. The recognition of pMN as an antibody-mediated autoimmune disease has rationalized the use immunosuppressive drugs such as rituximab. Rituximab is now a first line immunosuppressive therapy for patients with pMN with proven safety and efficacy achieving remission in 60-80% of patients. For the remaining 20-40% of patients, several mechanisms may explain rituximab resistance: (i) decreased rituximab bioavailability; (ii) immunization against rituximab; and (iii) chronic glomerular damage. The treatment of patients with rituximab-refractory pMN remains controversial and challenging. In this review, we provide an overview of recent advances in the management of pMN (according to the KDIGO 2021 guidelines), in the understanding of the pathophysiology of rituximab resistance, and in the management of rituximab-refractory pMN. We propose a treatment decision aid based on immunomonitoring to identify failures related to underdosing or immunization against rituximab to overcome treatment resistance.

The Role of Mycophenolate Mofetil for the Induction of Remission in ANCA-Associated Vasculitis: A Meta-Analysis

Objectives: The successful introduction of mycophenolate mofetil (MMF) as a treatment for renal allograft reduced the incidence of acute rejection. The inspiring effects obtained by the MMF have led to an evaluation of its therapeutic potency on ANCA-associated vasculitis (AAV). However, there is little evidence of the MMF's efficacy on the AAV. The meta-analysis is carried out to evaluate the efficacy of MMF as a remission induction therapy in AAV.

Methods: Up to June 30th, 2020, PubMed, Cochrane Library, and Embase have been searched comprehensively. According to heterogeneity, the pooled remission rates are synthesized by either fixed-effect or random-effect models.

Results: The eight included studies comprising 230 patients who were treated with MMF as induction therapy are included in our analysis. The pooled overall remission rate is 74% (95% CI: 0.68–0.80). The remission rate, the infection rate and the rate of leukopenia of four randomized controlled trials aimed at comparing the effects of MMF with cyclophosphamide (CYC) during induction therapy for AAV have no statistical significance (P > 0.05).

Conclusion: MMF may be an alternative to CYC for remission induction therapy in AAV with MPO-ANCA, mild to moderate renal involvement and non-life-threatening state. Whether to observe the effect of MMF in AAV or to compare the difference between MMF and CYC in the future studies, risk stratification and subgrouping of AAV patients should be first carried out to correctly identify the AAV subgroup suitable for MMF.

Mycophenolate mofetil and tacrolimus versus tacrolimus alone for the treatment of idiopathic membranous glomerulonephritis: a randomised controlled trial

Background

Tacrolimus (TAC) is effective in treating membranous nephropathy (MN); however relapses are frequent after treatment cessation. We conducted a randomised controlled trial to examine whether the addition of mycophenolate mofetil (MMF) to TAC would reduce relapse rate.

Methods

Forty patients with biopsy proven idiopathic MN and nephrotic syndrome were randomly assigned to receive either TAC monotherapy (n = 20) or TAC combined with MMF (n = 20) for 12 months. When patients had been in remission for 1 year on treatment the MMF was stopped and the TAC gradually withdrawn in both groups over 6 months. Patients also received supportive treatment with angiotensin blockade, statins, diuretics and anticoagulation as needed. Primary endpoint was relapse rate following treatment withdrawal. Secondary outcomes were remission rate, time to remission and change in renal function.

Results

16/20 (80%) of patients in the TAC group achieved remission compared to 19/20 (95%) in the TAC/MMF group (p = 0.34). The median time to remission in the TAC group was 54 weeks compared to 40 weeks in the TAC/MMF group (p = 0.46). There was no difference in the relapse rate between the groups: 8/16 (50%) patients in the TAC group relapsed compared to 8/19 (42%) in the TAC/MMF group (p = 0.7). The addition of MMF to TAC did not adversely affect the safety of the treatment.

Conclusions

Addition of MMF to TAC does not alter the relapse rate of nephrotic syndrome in patients with MN.

Trial registration

This trial is registered with EudraCTN2008–001009-41. Trial registration date 2008-10-08.

The Unpredictability of Idiopathic Membranous Nephropathy: An Illustrative Case Report

The case of a female patient with primary membranous nephropathy is presented. She was treated with corticosteroids and chlorambucil after conservative therapy had failed and went into remission for 5 years. Her nephrotic syndrome recurred but did not respond to the same regimen. She had another complete remission after treatment with corticosteroids and cyclosporine, but the nephrosis recurred after 7 years. Again, she failed to respond with retreatment of steroids plus cyclosporine. She was treated with alternate-day steroid plus mycophenolate and, once again, had a complete remission. She was maintained on low-dose mycophenolate for 7 more years. The mycophenolate had to be discontinued because of cytomegalovirus colitis. Treatment with ganciclovir abolished the colitis. She is still in remission 10 years later. The case is discussed with regard to current knowledge of the immune pathogenesis of membranous nephropathy as well as the unknowns of the immunogenesis of the disease.

The Effect of Mycophenolate Mofetil versus Cyclosporine as Combination Therapy with Low Dose Corticosteroids in High-risk Patients with Idiopathic Membranous Nephropathy: a Multicenter Randomized Trial

BACKGROUND

Appropriate immunosuppressive therapy for patients with idiopathic membranous nephropathy (MN) remains controversial. The effect of mycophenolate mofetil (MMF) versus cyclosporine (CsA) combined with low-dose corticosteroids was evaluated in patients with idiopathic MN in a multi-center randomized trial (www.ClinicalTrials.gov NCT01282073).

METHODS

A total of 39 biopsy-proven idiopathic MN patients with severe proteinuria were randomly assigned to receive MMF combined with low-dose corticosteroids (MMF group) versus CsA combined with low-dose corticosteroids (CsA group), respectively, and followed up for 48 weeks. Complete or partial remission rate of proteinuria and estimated glomerular filtration rate (eGFR) at 48 weeks were compared.

RESULTS

The level of proteinuria at baseline and at 48 weeks was 8.9 ± 5.9 and 2.1 ± 3.1 g/day, respectively, in the MMF group compared to 8.4 ± 3.5 and 3.2 ± 5.7 g/day, respectively, in the CsA group. In total, 76.1% of the MMF group and 66.7% of the CsA group achieved remission at 48 weeks (95% confidence interval, -0.18 to 0.38). There was no difference in eGFR between the two groups. Anti-phospholipase A2 receptor Ab levels at baseline decreased at 48 weeks in the complete or partial remission group (P = 0.001), but were unchanged in the no-response group. There were no significant differences between the two groups in changes in the Gastrointestinal Symptom Rating Scale and Gastrointestinal Quality of Life Index scores from baseline to 48 weeks.

CONCLUSION

In combination with low-dose corticosteroids, the effect of MMF may not be inferior to that of CsA in patients with idiopathic MN, with similar adverse effects including gastrointestinal symptoms. Trial registry at ClinicalTrials.gov (NCT01282073).

Treatment of primary membranous nephropathy: where are we now?

In the last 10 years, basic science and clinical research have made important contributions to the understanding and management of primary membranous nephropathy (MN). The identification of antibodies directed against the M-type phospholipase A₂ receptor (PLA2R) and thrombospondin type-1 domain-containing 7A protein have added a new perspective on diagnosis, monitoring the immunological activity, predicting prognosis and guiding therapy in patients with primary MN. Mounting evidence suggests that quantification and follow-up of antiPLA2R Abs levels can help in assessing prognosis and evaluate the response to treatment. The kidney disease improving global outcomes guidelines published in 2012 have not been updated. New data on the use of rituximab suggest it should be considered as a potential initial therapy in the treatment of patients with primary MN.

Mycophenolate mofetil in nonlupus glomerulonephropathy

Mycophenolate mofetil (MMF) initially found widespread use in the immunoprophylaxis of rejection in organ transplantation. It has subsequently been used in lupus glomerulonephritis, where early studies have shown it to be effective in induction and maintenance therapy. The randomized studies have mostly studied small groups of patients and their conclusions do need to be confirmed in larger studies. MMF has also been used in small numbers of patients in a variety of nonlupus glomerulopathies, which have different underlying immunopathology as well as clinical course, including IgA nephropathy, membranous nephropathy, focal segmental glomerulosclerosis, membranoproliferative glomerulonephritis, hepatitis-C-associated glomerulonephritis and even Goodpasture's syndrome. In this article, we discuss its use in such nonlupus glomerular diseases.

Mycophenolate and nephrology

Several large, randomized trials have established mycophenolate mofetil (MMF) as an effective immunosuppressant for kidney transplantation. Inhibition of inosine 5′-monophospate dehydrogenase (IMPDH) by MMF appears to have pleiotropic effects on both immune and non-immune cells. In addition to B- and T-cell inhibition, in vitro and in vivo data suggest that MMF also has inhibitory effects on smooth muscle cells, endothelial cells, and myofibroblasts, findings that may be relevant in considering treatment of primary immune mediated kidney diseases. Clinical trials have established the efficacy of MMF for the treatment of lupus nephritis, as discussed in detail elsewhere in this supplement. Although animal studies have provided the rationale for human trials of MMF in primary glomerular diseases, most of the evidence thus far is conflicting or based largely on pilot studies. Data from larger, controlled trials will soon emerge and may clarify the role of MMF in the treatment of these disorders.

De novo membranous nephropathy in renal allograft associated with antibody-mediated rejection and review of the literature

A 71-year-old woman with unknown renal failure etiology received living donor transplantation had normal graft function for many years. At 11 years from transplantation, she developed nephrotic syndrome. Allograft biopsy showed membranous nephropathy (MN) and C4d positivity in the peritubular capillaries, suggestive of antibody-mediated rejection. At the time of nephrosis onset, she had new donor-specific antibody positivity. The case is unusual in that the diagnosis of de novo MN is based on evidence that she had antibody-mediated rejection. De novo MN remains relatively uncommon; we have reviewed the literature on this diagnosis.

Diagnostic tests and treatment options in glomerular disease: 2014 update

Glomerular diseases historically have been challenging disorders to comprehend and treat for patients and physicians alike. Kidney biopsy is the gold standard of diagnosis, but the link between pathophysiology and the histologic representation of kidney injury has remained elusive in many of these diseases. As a result, treatment of glomerular disease usually involves therapies that are not specific to disease pathogenesis, such as blockade of the renin-angiotensin-aldosterone system and various immunosuppression regimens. Recent research has resulted in greater insight into some glomerular diseases, leading to the hope that new diagnostic tests and treatments targeting disease-specific mechanisms are on the horizon. We review recent progress on the understanding, diagnosis, and treatment of 4 glomerular diseases: immunoglobulin A nephropathy, focal segmental glomerulosclerosis, the C3 glomerulopathies, and idiopathic membranous nephropathy.

[Membranous nephropathy]

Membranous nephropathy is characterized by immune complex deposits on the outer side of the glomerular basement membrane. Activation of complement and of oxidation lead to basement membrane lesions. The most frequent form is idiopathic. At 5 and 10 years, renal survival is around 90 and 65% respectively. A prognostic model based on proteinuria, level and duration, progression of renal failure in a few months can refine prognosis. The urinary excretion of C5b-9, β2 and α1 microglobuline and IgG are strong predictors of outcome. Symptomatic treatment is based on anticoagulation in case of nephrotic syndrome, angiotensin conversion enzyme inhibitors, angiotensin II receptor blockers and statins. Immunosuppressive therapy should be discussed for patients having a high risk of progression. Corticoids alone has no indication. Treatment should include a simultaneous association or more often alternating corticoids and alkylant agent for a minimum of 6 months. Adrenocorticoid stimulating hormone and steroids plus mycophenolate mofetil may be equally effective. Steroids plus alkylant decrease the risk of end stage renal failure. Cyclosporine and tacrolimus decrease proteinuria but are associated with a high risk of recurrence at time of withdrawal and are nephrotoxic. Rituximab evaluated on open studies needs further evaluations to define its use.

Treatment of idiopathic membranous nephropathy

Immunosuppressive treatment of patients with idiopathic membranous nephropathy (iMN) is heavily debated. The controversy is mainly related to the toxicity of the therapy and the variable natural course of the disease-spontaneous remission occurs in 40-50% of patients. The 2012 Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guideline for Glomerulonephritis provides guidance for the treatment of iMN. The guideline suggests that immunosuppressive therapy should be restricted to patients with nephrotic syndrome and persistent proteinuria, deteriorating renal function or severe symptoms. Alkylating agents are the preferred therapy because of their proven efficacy in preventing end-stage renal disease. Calcineurin inhibitors can be used as an alternative although efficacy data on hard renal end points are limited. In this Review, we summarize the KDIGO guideline and address remaining areas of uncertainty. Better risk prediction is needed to identify patients who will benefit from immunosuppressive therapy, and the optimal timing and duration of this therapy is unknown because most of the randomized controlled trials were performed in low-risk or medium-risk patients. Alternative therapies, directed at B cells, are under study. The discovery of anti-M type phospholipase A2 receptor-antibodies is a major breakthrough and we envisage that in the near future, antibody-driven therapy will enable more individualized treatment of patients with iMN.

Treatment of idiopathic membranous nephropathy

Exciting progress recently has been made in our understanding of idiopathic membranous nephropathy, as well as treatment of this disease. Here, we review important advances regarding the pathogenesis of membranous nephropathy. We will also review the current approach to treatment and its limitations and will highlight new therapies that are currently being explored for this disease including Rituximab, mycophenolate mofetil, and adrenocorticotropic hormone, with an emphasis on results of the most recent clinical trials.

Membranous nephropathy in children: clinical presentation and therapeutic approach

The approach to the pediatric patient with membranous nephropathy (MN) can be challenging to the practitioner. The clinical presentation of the child with this histologic entity usually involves some degree of proteinuria ranging from persistent, subnephrotic-ranged proteinuria to overt nephrotic syndrome. Patients often have accompanying microscopic hematuria and may have azotemia or mild hypertension. Children presenting with nephrotic syndrome are often steroid resistant; as such, their biopsy for steroid-resistant nephrotic syndrome results in the diagnosis of MN. The practitioner treating MN in the pediatric patient must weigh the risks of immunosuppressive therapy against the benefits. In general, the child with subnephrotic proteinuria and normal renal function can likely be treated conservatively with angiotensin blockade (angiotensin-converting enzyme inhibitors or angiotensin receptor blockers) without the need for immunosuppressive therapy. Those with nephrotic syndrome are usually treated with steroids initially and often followed by alkylating agents (cyclophosphamide or chlorambucil). Calcineurin inhibitors may also be useful, but the relapse rate after their discontinuation remains high. The absence of controlled studies in children with MN makes treatment recommendations difficult, but until they are available, using the patient's clinical presentation and risk of disease progression appears to be the most prudent approach.

The accumulated experience with the use of mycophenolate mofetil in primary glomerulonephritis

IMPORTANCE OF THE FIELD

The use of mycophenolate mofetil (MMF) has been extended from renal transplantation to the treatment of glomerulonephritis. MMF has been used in patients with steroid- and ciclosporin A (CsA)-dependent or -resistant idiopathic nephrotic syndrome and in patients with deteriorating renal function or adverse reactions to other drugs. MMF has been also used in patients with membranous and IgA nephropathy after failure of other regimens as well as initial treatment.

AREAS COVERED IN THIS REVIEW

The rationale of MMF treatment in primary glomerulonephritis is based in its antifibrotic and antiproteinuric effects. The mechanism of action is described; the results of cohort and randomized trials in minimal change disease, focal segmental glomerulosclerosis, idiopathic membranous nephropathy and IgA nephropathy are presented along with the adverse reactions profile and the expert opinion.

WHAT THE READER WILL GAIN

This is an up-to-date review providing insight on this novel agent that is increasingly used in the therapeutics of primary glomerulonephritis.

TAKE HOME MESSAGE

Although the results are conflicting, MMF seems to be effective at least in some patients, who do not respond to corticosteroids, ciclosporin or cytotoxic drugs. However, the experience with MMF in primary glomerulonephritis is limited and further research is required in order to establish MMF in the treatment of patients with glomerular disease.

Mycophenolate mofetil in children with steroid/cyclophosphamide-resistant nephrotic syndrome

The purpose of this study was to assess the results of therapy with mycophenolate mofetil (MMF) in children with idiopathic nephrotic syndrome (INS) who were both steroid- and cyclophosphamide-resistant. Treatment lasted a minimum of 6 months, and follow-up data were collected over a 2-year period. The children were divided into two groups: Group 1 (n=34) comprised patients who had received cyclosporine A (CsA) before the initiation of MMF therapy; Group 2 (n=18) comprised patients who received only MMF. Among the 34 patients of Group 1, complete and partial remission were achieved in seven (20.6%) and 13 patients (38.6%), respectively; there was no response in 14 patients (41.2%). Among the 18 patients in Group 2, complete and partial remission occurred in five (27.8%) and six (33.3%) patients, respectively; there was no response in seven patients (38.9%). Eight patients developed chronic kidney disease. The main side-effects were gastrointestinal complaints (n=11, 21%), recurring severe infections (n=1, 1.9%), and mild thrombocytopenia/leucopenia (n=1, 1.9%). MMF proved to be therapeutically effective in 59.5% of the cases. These beneficial effects need to be confirmed in studies with a long-term follow-up after discontinuation of the treatment. Our statistical analysis of the results of therapy with MMF did not reveal any significant difference between its use alone or following CsA administration.

Mycophenolate mofetil for induction and maintenance of remission in microscopic polyangiitis with mild to moderate renal involvement--a prospective, open-label pilot trial

BACKGROUND AND OBJECTIVES

Microscopic polyangiitis (MPA) is a systemic small-vessel vasculitis associated with anti-neutrophil cytoplasmic antibodies (ANCA), often targeting myeloperoxidase (MPO). Cyclophosphamide (CYC) plus corticosteroids (CS) is considered standard therapy for patients with renal involvement, but treatment response is not satisfactory in all patients and CYC has well recognized toxicity. This prospective pilot trial explored whether mycophenolate mofetil (MMF) represents an effective alternative to CYC for induction and maintenance of remission in MPA with mild to moderate renal involvement.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Seventeen P-ANCA/MPO-ANCA-positive patients with MPA with mild to moderate renal involvement received MMF (1000 mg orally, twice daily) and CS (intravenous methylprednisolone, 1 to 3 g, followed by oral prednisone at 1 mg/kg per day). Oral CS were discontinued by month 6; MMF was continued through month 18. The primary outcome measure was remission by month 6 and stable renal function. Secondary endpoints included major relapses necessitating a switch to CYC plus CS, minor relapses requiring an increase in CS dosage, and adverse events.

RESULTS

Thirteen of 17 patients enrolled achieved the primary outcome, and 4 failed because of insufficient response, relapse, or MMF intolerance. Twelve patients remained in remission through month 18, renal function remained stable, and proteinuria improved. Side effects of MMF were mild, transient, and responsive to dose adjustments in all patients except one.

CONCLUSIONS

MMF represents an alternative to CYC for induction and maintenance of remission in patients with MPO-ANCA-associated MPA with mild to moderate renal disease.

Controversies in the treatment of idiopathic membranous nephropathy

Optimum treatment of idiopathic membranous nephropathy is both controversial and challenging. The most extensively studied and frequently used immunosuppressive regimens for this disease comprise alkylating agents plus corticosteroids or ciclosporin. All of these treatment options have inherent problems: they are not effective in all patients, partial-rather than complete-remissions are common, adverse effects are worrisome, and relapses after treatment cessation remain problematic. Alternative immunosuppressive agents have been tested in an effort to overcome these unresolved issues. This paper reviews the available evidence regarding both established and new agents for the treatment of patients with idiopathic membranous nephropathy, with an emphasis on the results of the most recent clinical trials.

Impact of immunosuppressive medication on the risk of renal allograft failure due to recurrent glomerulonephritis

Recurrent glomerulonephritis is a major problem in kidney transplantation but the role of immunosuppression in preventing this complication is not known. We used data from the United States Renal Data System to examine the effect of immunosuppressive medication on allograft failure due to recurrent glomerulonephritis for 41,272 patients undergoing kidney transplantation from 1990 to 2003. Ten-year incidence of graft loss due to recurrent glomerulonephritis was 2.6% (95% confidence interval [CI]: 2.3-2.8%). After adjusting for important covariates, the use of cyclosporine, tacrolimus, azathioprine, mycophenolate mofetil, sirolimus or prednisone was not associated with graft failure due to recurrent glomerulonephritis. There was no difference between cyclosporine and tacrolimus or between azathioprine and mycophenolate mofetil in the risk of graft failure due to recurrent glomerulonephritis. However, any change in immunosuppression during follow-up was independently associated with graft loss due to recurrence (adjusted hazard ratio 1.30, 95% CI: 1.06-1.58, p = 0.01). In patients with a pretransplant diagnosis of glomerulonephritis, the risk of graft loss due to recurrence was not associated with any specific immunosuppressive medication. The selection of immunosuppression for kidney transplant recipients should not be made with the goal of reducing graft failure due to recurrent glomerulonephritis.

An update on the use of mycophenolate mofetil in lupus nephritis and other primary glomerular diseases

Mycophenolate mofetil (MMF) has been used successfully as an immunosuppressive medication in transplantation for over a decade. Owing to its efficacy and relatively benign adverse effect profile, its use has been investigated in the treatment of several glomerular diseases, as we describe in this Review. Of these, MMF has most extensively been studied in lupus nephritis. Randomized controlled trials have documented the value of MMF in both induction and maintenance therapy for severe lupus nephritis in several different geographic and ethnic populations, and have defined its potential toxicity. In minimal-change disease, focal segmental glomerulosclerosis and membranous nephropathy, promising but limited data on MMF treatment exist from small retrospective and prospective studies. Ongoing, larger, prospective trials, such as the NIH trial in focal segmental glomerulosclerosis, might clarify the value of MMF in the treatment of this disease. The efficacy of MMF in IgA nephropathy remains unclear, despite several small, controlled trials. Conflicting results might reflect differences in the disease process, differences in MMF metabolism, or varying responses to the immunosuppressive agent in different populations. Only through large, collaborative, controlled trials will the true role of MMF be defined for each glomerular disease.

Mycophenolate mofetil therapy for children with intractable nephrotic syndrome

BACKGROUND

Cyclosporin A (CyA) can suppress relapses and reduce proteinuria in frequent-relapse nephrotic syndrome (FRNS) and steroid-resistant nephrotic syndrome (SRNS). However, some patients remain resistant to CyA therapy. The purpose of the present paper was to evaluate mycophenolate mofetil (MMF) treatment in pediatric patients with CyA-resistant intractable nephrotic syndrome.

METHODS

MMF therapy was given to 11 patients with FRNS who had relapse despite CyA therapy, and one patient with SRNS who had been receiving combined therapy using steroid and CyA until immediately before the start of MMF. MMF was administered at a daily dose of 750-1000 mg/m(2) in two divided doses.

RESULTS

Ten of the 11 patients with FRNS were able to maintain remission. Among them, seven patients remained relapse free for 1 year, and two patients had a decrease in the frequency of relapse after initiation of MMF therapy. One patient, however, had repeated cycles of remission and relapse, and was considered resistant to MMF therapy. The total prednisolone dose during the period from month 6 to month 12 after the start of MMF therapy was significantly lower than that during the 6 month period before the start of MMF therapy. The patient with SRNS, who had not achieved remission despite CyA administration, had complete remission on MMF. No serious adverse effects were seen in any of the present patients.

CONCLUSION

MMF could be useful in CyA-treatment-refractory FRNS and CyA-resistant SRNS.

Mycophenolate mofetil in idiopathic membranous nephropathy: a clinical trial with comparison to a historic control group treated with cyclophosphamide

BACKGROUND

Cyclophosphamide can decrease proteinuria and improve renal function in patients with idiopathic membranous nephropathy, but has a high risk of side effects. We studied whether mycophenolate mofetil (MMF) could be a reasonable alternative with fewer side effects.

STUDY DESIGN

Clinical trial with historic controls.

SETTINGS & PARTICIPANTS

32 cases and 32 controls with idiopathic membranous nephropathy and renal insufficiency at multiple centers. For comparison, we selected matched historic controls treated with cyclophosphamide.

INTERVENTION

MMF, 1 g twice daily, for 12 months versus cyclophosphamide, 1.5 mg/kg/d, for 12 months. Both groups also received intermittent methylprednisolone and alternate-day prednisone.

OUTCOMES & MEASUREMENTS

Serum creatinine, proteinuria, and side effects during and after treatment.

RESULTS

Median follow-up was 23 months (range, 11 to 46 months). Median serum creatinine levels were 1.8 mg/dL (159 micromol/L) in both groups at baseline and 1.4 mg/dL (124 micromol/L) in the MMF group versus 1.3 mg/dL (115 micromol/L) in the cyclophosphamide group at 12 months (P = 0.4). Proteinuria values at baseline and 12 months were protein of 8.40 and 1.41 g/d in the MMF group versus 9.19 and 1.13 g/d in the cyclophosphamide group (P = 0.5 at 12 months), respectively. Cumulative incidences of remission of proteinuria at 12 months were 66% in the MMF group versus 72% in the cyclophosphamide group (P = 0.3). Five patients (16%) in the MMF group versus none in the cyclophosphamide group had disease that did not respond to therapy (P = 0.05). Twelve patients (38%) experienced a relapse and 9 patients (31%) were re-treated in the MMF group compared with 4 (13%) and 2 patients (6%) in the cyclophosphamide group (P < 0.01 and P = 0.024, respectively). Side effects occurred in 24 patients (75%) in the MMF group and 22 patients (69%) in the cyclophosphamide group (P = 0.6).

LIMITATIONS

Nonrandomized control group, short duration of follow-up.

CONCLUSIONS

A 12-month course of MMF decreased proteinuria and improved renal function in the majority of patients, but did not appear as effective or better tolerated than cyclophosphamide. Long-term data and randomized controlled trials are needed to ascertain the efficacy of MMF in patients with idiopathic membranous nephropathy.

Tacrolimus in the treatment of idiopathic nephrotic syndrome

The immunosuppressant tacrolimus (FK-506) is a calcineurin inhibitor with a widespread use for the prevention of graft rejection in transplantation medicine. Tacrolimus inhibits the activation of an essential transcription factor for the transcription of cytokine genes in T cells leading to a decreased production of cytokines such as IL-2 and IFN-gamma. As T-cell activation plays a crucial role in the pathogenesis of inflammatory glomerular diseases, there is an increasing number of reports on the use of tacrolimus in nephrotic syndrome. In idiopathic nephrotic syndrome, corticosteroid treatment constitutes the first-line therapy to achieve remission. In the case of steroid resistance or steroid dependence, alternative immunosuppressive strategies are needed. Cyclophosphamide and ciclosporin are well-established drugs in this condition. The present article reviews the pharmacodynamics, pharmacokinetics, safety and clinical efficacy of tacrolimus in steroid-resistant and steroid-dependent nephrotic syndrome.

Membranous nephropathy: when and how to treat

The treatment of idiopathic membranous nephropathy is heavily debated because of wide variation in outcome. A rational treatment strategy is needed to appropriately administer conservative treatment to the low-risk group but immunosuppressive therapy to those with medium or high risk of renal deterioration. Currently, combinations of steroids with alkylating agents are best studied. Newer forms of immunosuppressive treatment are currently under study.

Mycophenolate mofetil treatment for therapy-resistant glomerulopathies

BACKGROUND

The management of steroid-resistant glomerulopathies remains a clinical problem. In this trial, we report a clinical observation of 43 patients treated with mycophenolate mofetil (MMF) for steroid-resistant glomerulopathies.

METHODS

All patients underwent renal biopsies, and immunofluorescence and light microscopy examinations were conducted in all cases. All patients had been treated with prednisone at a dose of 1 mg/kg per day for at least 8 weeks. Of the 43 patients, 16 were treated with cyclophosphamide and five were treated with cyclosporine A before MMF started. The primary study outcomes were the change in the urinary protein excretion, serum creatinine, comparing the levels at the start of MMF treatment with those at the end of the MMF treatment period. Changes in renal function were also estimated with Modification of Diet in Renal Failure calculation. Wilcoxon signed-ranks test was used as appropriate to compare data from the start with data at the end of the treatment period.

RESULTS

The primary glomerular diseases represented included membranoproliferative glomerulonephritis in 23.2%, membranous glomerulonephritis in 18.6%, IgA nephropathy in 13.9%, focal segmental glomerulosclerosis in 9.3%, lupus nephritis (systemic lupus erythematosus) in 25.6% and pauci-immune glomerulopathy in 9.3% of patients. The mean follow-up time was 28.9+/-12 months. Before MMF treatment, 16 patients (37%) had nephrotic range proteinuria and 11 (26%) had renal insufficiency. The urinary protein before MMF treatment was 3.3+/-2.6 g/dL (0.6-9.6) and decreased significantly to 0.87+/-1.1 g/dL (0-5.5) at the end of the MMF treatment period (P=0.02). During treatment, complete remission was seen in 27 patients, partial remission in 10 patients and MMF failure in six patients. The serum creatinine level decreased significantly from 1.29+/-0.55 mg/dL (0.6-3.0) to 1.14+/-0.38 mg/dL (0.5-2.4) post MMF therapy (P=0.046). Using the four-variable Modification of Diet in Renal Failure formula, the glomerular filtration rate increased from 71.5+/-28 mL/min per 1.73 m2 to 78.1+/-27 mL/min per 1.73 m2 (P=0.021). Renal insufficiency resolved in seven of the 11 (63.6%) patients with renal insufficiency initially, two with membranoproliferative glomerulonephritis, two with membranous glomerulonephritis, one with focal segmental glomerulosclerosis, four with pauci-immune glomerulopathy, two with systemic lupus erythematosus nephritis, and in two patients de novo renal insufficiency developed.

CONCLUSION

In general, MMF was well tolerated, and most of the patients achieved remission and improvement of renal functions. MMF treatment appeared to offer benefits to problematic patients refractory to conventional therapies for glomerulopathies.

Tacrolimus monotherapy in membranous nephropathy: A randomized controlled trial

Membranous nephropathy is a common cause of nephrotic syndrome in adults. Although some patients with membranous nephropathy achieve a spontaneous remission, renal function continues to deteriorate in others. We conducted a prospective randomized trial evaluating monotherapy with tacrolimus to achieve complete or partial remission in patients with biopsy-proven membranous nephropathy. Twenty-five patients received tacrolimus (0.05 mg/kg/day) over 12 months with a 6-month taper, whereas 23 patients were in the control group. The probability of remission in the treatment group was 58, 82, and 94% after 6, 12, and 18 months but only 10, 24, and 35%, respectively in the control group. The decrease in proteinuria was significantly greater in the treatment group. Notably, six patients in the control group and only one in the treatment group reached the secondary end point of a 50% increase in their serum creatinine. No patient in the tacrolimus group showed a relapse during the taper period. Nephrotic syndrome reappeared in almost half of the patients who were in remission by the 18th month after tacrolimus withdrawal. We conclude that tacrolimus is a very useful therapeutic option for patients with membranous nephropathy and preserved renal function. The majority of patients experienced remission with a significant reduction in the risk for deteriorating renal function.

Mycophenolate mofetil is effective in reducing lupus glomerulonephritis proteinuria

Mycophenolate mofetil (MMF) significantly reduces proteinuria in experimental model of human membranous nephropathy (Heymann nephritis). Twenty consecutive SLE patients with persistent isolated severe proteinuria and/or proteinuric flare were studied for 18 months of MMF therapy. All of them presented stable renal function and 12 had biopsy proven membranous glomerulonephritis (WHO class V). The starting daily dose for MMF was 1.5 g to a maximum of 3 g. Patients were divided into: partial response, >or=50% decrease of baseline proteinuria; complete response, normal proteinuria levels (less than 0.3 g/24 h); flare, increase of at least 50% of the mean baseline proteinuria. All 20 SLE patients (100%) presented a 50% reduction of baseline proteinuria which was achieved in 8.2+/-3.3 months of MMF therapy, at a mean daily dose of 2.3+/-0.5 g. A significant decrease in 24-h protein excretion was observed compared to entry (3.47+/-1.26 vs. 1.33+/-0.67 g, P<0.0001) as well as a correspondent increase of serum albumin (3.2+/-0.4 vs. 3.7+/-0.4 mg/dl, P=0.02) and reduction of prednisone dose (33.7+/-20.0 to 18.6+/-14.1 mg/day, P=0.01). Complete response was observed in 11 SLE patients (55%) in 12.2+/-3.0 months of therapy with a significant decrease in proteinuria (P<0.0001), prednisone dose (P<0.0001) and an increase of serum albumin (P=0.003). Interestingly, initial proteinuria or serum albumin levels did not identify patients with complete response and those with partial response at the end of the study (P=0.543 and 0.657, respectively). Our pilot prospective study suggests that MMF appears to be effective in reducing severe persistent proteinuria in lupus glomerulonephritis, even in patients unresponsive to other immunosuppressive treatments.

Mycophenolate Mofetil for the Treatment of Interstitial Nephritis

Acute interstitial nephritis (AIN) is a clinicopathologic entity that is characterized by acute renal failure and renal biopsy findings of interstitial inflammation and tubulitis. There are multiple causes of AIN, the majority of which appear to respond to immunosuppressive therapy. Corticosteroids are the mainstay of treatment for AIN, but many patients are refractory to or intolerant of treatment or are unable to discontinue therapy without clinical relapse. Herein are reported eight cases of steroid-resistant, biopsy-proven AIN that were treated successfully with mycophenolate mofetil (MMF) at one institution. Patients had a mean decline in serum creatinine from 2.3 to 1.6 mg/dl over a mean of 24.3 mo of treatment. Six of the eight patients had a decline in serum creatinine of at least 0.3 mg/dl, and the remaining two patients had stable renal function during the treatment period. At most recent follow-up, five of the eight patients successfully have discontinued treatment with MMF for a mean of 6.4 mo. MMF was well tolerated by all patients. It is concluded that MMF is a useful therapeutic option for steroid-resistant AIN and may be considered as potential first-line therapy in select populations.

Idiopathic Membranous Nephropathy: Outline and Rationale of a Treatment Strategy

Idiopathic membranous nephropathy is a common cause of nephrotic syndrome. The treatment of patients with idiopathic membranous nephropathy is heavily debated. Based on literature data and our own experience, we propose a rational treatment strategy. Patients with renal insufficiency (serum creatinine level > 1.5 mg/dL [> 135 micromol/L]) are at greatest risk for the development of end-stage renal disease and should receive immunosuppressive therapy. In patients with normal renal function (serum creatinine level < 1.5 mg/dL [< 135 micromol/L]), risk for developing end-stage renal disease can be estimated by measuring urinary excretion of beta2-microglobulin or alpha1-microglobulin and immunoglobulin G. For low-risk patients, a wait-and-see policy is advised. High-risk patients likely benefit from immunosuppressive therapy. Currently, combinations of steroids with chlorambucil or cyclophosphamide are the best studied. We prefer cyclophosphamide in view of its fewer side effects. Cyclosporine may be an alternative option in patients with well-preserved renal function, although long-term data are lacking. Other immunosuppressive agents, such as mycophenolate mofetil or rituximab, currently are under study; however, data are insufficient to support their routine use.

Use of Mycophenolate Mofetil in Autoimmune and Renal Diseases

Progress in understanding the pathogenesis and treatment of rheumatologic and glomerular diseases such as systemic lupus erythematosus and particularly lupus nephritis has been closely linked with the development of newer immunosuppressive agents. With improved patient survival following the institution of cyclophosphamide and corticosteroid therapy, longer-term management issues came to the forefront, especially how to decrease adverse effects of the immunosuppressive regimen. Many of the immunosuppressive regimens used in lupus patients were first established as efficacious and safe through their use in solid organ transplantation. Mycophenolate mofetil (MMF) is now widely used in the field of transplantation. Following anecdotal reports describing benefits of MMF in lupus and lupus nephritis patients, small studies and finally large randomized, controlled trials have established the use of MMF in these patients, particularly those with lupus nephritis. MMF use in other rheumatologic and renal diseases has been evaluated in only smaller studies and very few randomized controlled trials. Nevertheless, many studies currently are ongoing with this immunosuppressive agent. This article will review the published data and the experience of two major New York medical centers with the use of MMF in autoimmune and renal diseases.

Mycophenolate mofetil in children with steroid-dependent and/or frequently relapsing nephrotic syndrome

BACKGROUND

Mycophenolate mofetil (MMF) has emerged as a new agent for treatment of a variety of glomerular diseases. This study examines the safety and efficacy of MMF in treating pediatric patients with steroid-dependent (SD) and/or frequently relapsing (FR) nephrotic syndrome (NS).

METHODS

We retrospectively reviewed the medical records of 18 patients with SDNS and/or FRNS treated with MMF for at least 3 months. MMF was used in 11 patients with SDNS (n=10) and FRNS (n=1), including 7 males and 4 females.

RESULTS

Mean age at time of diagnosis of NS was 3.3 years (range, 1.1-8.5 years), and at the start of MMF 5.9 years (range, 2.9-10 years). Seven patients had a renal biopsy prior to starting MMF; all had mesangial proliferative glomerulonephritis. Mean follow-up after starting MMF was 12.2 months (range, 4-24 months). Mean MMF dose was 948 mg/m2/day (range, 500-1087 mg/m2/day). MMF resulted in improvement in 9 of 11 patients, with 8 patients weaned off steroids completely, with a reduction in the mean relapse rate from 4.7 relapses/patient/year (range, 2.4-6) before MMF to 1.05 relapses/patient/year (range, 0-4.5) after MMF therapy (P=0.0001). The relative risk for relapse before MMF was 4.7 (P=0.0002). None of the patients had significant adverse events or intolerance to MMFtherapy.

CONCLUSION

We conclude that MMF is a safe and effective option for treatment of children with SDNS and/or FRNS.

Reduction of proteinuria with mycophenolate mofetil in predominantly membranous lupus nephropathy

INTRODUCTION

Lupus membranous nephropathy (LMN) presents a difficult clinical problem as no particular treatment has been proven to be effective. Studies have shown good results with mycophenolate mofetil (MMF) in proliferative lupus nephropathy (LN) (WHO class III and IV disease).

OBJECTIVES

To study whether MMF treatment was effective in membranous predominant LN in patients resistant to or intolerant of other immunosuppressive agents.

PATIENTS AND METHODS

We retrospectively studied 10 patients with systemic lupus erythematosus who had biopsy-proven predominant LMN (six Vc patients and four Va or Vb patients). Previous treatments included cyclophosphamide, azathioprine, ciclosporin and corticosteroids. The following parameters were recorded at baseline and follow-up: blood pressure, ECLAM, proteinuria, serum albumin and creatinine, routine haematology and immunology.

RESULTS

The study included eight women and two men, mean age 38.4 +/- 7.1 yr (range 30-49 yr). The racial distribution was as follows: five Caucasian, and five Black patients. The mean treatment time with MMF was 18.8 +/- 15.4 months (range 3-52 months). Twenty-four-hour urinary protein excretion was reduced from median 2.26 g (range 0-7.92 g) to median 0.66 g (range 0.08-3.85 g) at follow-up (P = 0.0039). Serum albumin increased significantly after treatment from median 29.5 g/l (range 14.0-42.0 g/l) to 33.5 g/l (range 23.0-40.0 g/l) at follow-up (P = 0.04). There were no significant changes in serum creatinine (P = 0.55).

CONCLUSION

MMF is a potentially useful immunosuppressive agent in reducing the proteinuria associated with membranous predominant LN.

Different effect of cyclosporine A and mycophenolate mofetil on passive Heymann nephritis in the rat

BACKGROUND

While cyclosporine A (CsA) is an effective therapy for nephrotic syndrome, it has nephrotoxic side effects. We compared the anti-proteinuric effects and nephrotoxicity in rats with passive Heymann nephritis (PHN) of CsA and mycophenolate mofetil (MMF).

METHODS

PHN was induced in female Wistar rats. Two treatment groups consisting of 8 rats each received either 25 mg of CsA or 25 mg of MMF/kg body weight/day and were compared with untreated controls. Kidney function and proteinuria were monitored over 4 weeks. Western blots were used for densitometric analysis of renal cyclooxygenase-2 (COX-2) protein expression. Thromboxane B2 (TxB2) and 6-keto-PGF(1alpha) were determined by radioimmunoassays (RIAs) in renal tissue and urine.

RESULTS

Rats with PHN exhibited a marked proteinuria of 12.76 +/- 4.42 vs. 0.73 +/- 0.28 mg/24 h (p < 0.01) and showed increased glomerular concentrations of TxB2 and 6-keto-PGF(1alpha) (992.6 +/- 216.9 and 1,187.0 +/- 54.2 pg/mg protein, respectively) compared with healthy controls (595 +/- 196.17 and 729 +/- 297.84, respectively) and a strongly induced COX-2 protein expression. CsA and MMF treatment reduced PHN-related proteinuria to 2.10 +/- 1.47 and 1.47 +/- 7.2 mg/24 h, respectively. In rats with PHN, CsA induced a significant deterioration of renal function and enhanced urine excretion of thromboxane A2, paralleled by a significant, twofold increase in COX-2 protein expression and renal prostaglandins. By contrast, MMF treatment in rats with PHN was not nephrotoxic and had no effect on prostaglandin production. COX-2 protein expression under MMF was suppressed.

CONCLUSION

While the antiproteinuric efficacy of MMF and CsA in PHN was comparable, the absence of nephrotoxicity might favor MMF in the treatment of nephrotic syndrome. The CsA-induced increase in COX-2 expression and COX-2-dependent prostacyclin may indicate a mechanism that compensates nephrotoxicity in the diseased and CsA-exposed kidney.

Mycophenolate mofetil in nonlupus glomerulonephropathy

Mycophenolate mofetil (MMF) initially found widespread use in the immunoprophylaxis of rejection in organ transplantation. It has subsequently been used in lupus glomerulonephritis, where early studies have shown it to be effective in induction and maintenance therapy. The randomized studies have mostly studied small groups of patients and their conclusions do need to be confirmed in larger studies. MMF has also been used in small numbers of patients in a variety of nonlupus glomerulopathies, which have different underlying immunopathology as well as clinical course, including IgA nephropathy, membranous nephropathy, focal segmental glomerulosclerosis, membranoproliferative glomerulonephritis, hepatitis-C-associated glomerulonephritis and even Goodpasture's syndrome. In this article, we discuss its use in such nonlupus glomerular diseases.

Mycophenolate mofetil in IgA nephropathy: results of a 3-year prospective placebo-controlled randomized study

BACKGROUND

Because humoral immunity is believed to play a pivotal role in the pathogenesis of IgA nephropathy (IgAN), a prospective placebo-controlled randomized study was started in patients with IgAN using mycophenolate mofetil (MMF).

METHODS

A total of 34 patients with IgAN were treated with salt intake restriction, angiotensin-converting enzyme (ACE) inhibition and MMF 2 g per day (N= 21) or placebo (N= 13). After 36 months of follow-up clinical, biochemical, and radiologic data were analyzed using linear mixed models for longitudinal data and Kaplan-Meier survival analysis.

RESULTS

Therapy had to be stopped prematurely in five patients. Two patients (MMF group) evolved to end-stage renal disease (ESRD). There was no difference between groups in the percentage of patients with a decrease of 25% or more in the inulin clearance or with a serum creatinine increase of 50% or more over 3 years. There was also no significant difference between groups in annualized rate of change of serum creatinine, computed by linear regression analysis. No significant difference was noted between groups for inulin clearance, serum creatinine, proteinuria, blood pressure, or other parameters of renal function. Hemoglobin and C-reactive protein were significantly lower in the MMF group compared with the placebo group. As a function of time, a significant decline in both groups was noted of proteinuria, parenchymal thickness of the kidneys and C3d.

CONCLUSION

In patients with IgAN at risk for progressive disease, no beneficial effect of 3-year treatment with MMF 2 g per day could be demonstrated on renal function/outcome or proteinuria. However, larger randomized studies are needed to confirm or reject these results.