Mycophenolate mofetil therapy in lupus nephritis: clinical observations

New guidelines and therapeutic updates for the management of lupus nephritis

PURPOSE OF REVIEW

Systemic lupus erythematosus (SLE) can be a devastating condition, striking young patients often in their prime reproductive years. Lupus nephritis is a common and serious complication occurring in roughly 50% of SLE cases, indicating a high likelihood of disease progression, morbidity, and mortality. As the early trials of steroid therapy, and later cyclophosphamide (CYC), therapeutic changes had been stagnant. Then came the introduction of mycophenolate mofetil (MMF) in the 2000s. After the Aspreva Lupus Management Study, there had been a dearth of trials showing positive therapy results. Since 2020, new studies have emerged for lupus nephritis involving the use of anti-BLYS agents, novel calcineurin inhibitors, CD20 blockade, and antiinterferon agents. Nephrology and rheumatology society guidelines in the United States and across the world are still catching up.

RECENT FINDINGS

Although therapeutic guidelines are being developed, updates that have come through have focused on improved diagnostic and monitoring guidelines. One theme is the recommendation of increasingly tight proteinuria control and firmer guidelines for the rapid induction of remission. The reality of multitarget therapy and the expectation of rapid induction for a more complete remission are being widely recognized.

SUMMARY

The need for more complete and more rapid induction and control of lupus nephritis is undisputed according to the evidence and guidelines, and the medications to achieve this are growing at a rate not seen over the prior two decades. What remains is a stepwise approach to recognize how to best optimize therapy. Based on available evidence, an algorithm for induction and maintenance treatment of lupus nephritis used by the University of California Irvine Lupus Nephritis clinic, is recommended.

Lupus Nephritis Risk Factors and Biomarkers: An Update

Lupus nephritis (LN) represents the most severe organ manifestation of systemic lupus erythematosus (SLE) in terms of morbidity and mortality. To reduce these risks, tremendous efforts have been made in the last decade to characterize the different steps of the disease and to develop biomarkers in order to better (i) unravel the pre-SLE stage (e.g., anti-nuclear antibodies and interferon signature); (ii) more timely initiation of therapy by improving early and accurate LN diagnosis (e.g., pathologic classification was revised); (iii) monitor disease activity and therapeutic response (e.g., recommendation to re-biopsy, new urinary biomarkers); (iv) prevent disease flares (e.g., serologic and urinary biomarkers); (v) mitigate the deterioration in the renal function; and (vi) reduce side effects with new therapeutic guidelines and novel therapies. However, progress is poor in terms of improvement with early death attributed to active SLE or infections, while later deaths are related to the chronicity of the disease and the use of toxic therapies. Consequently, an individualized treat-to-target strategy is mandatory, and for that, there is an unmet need to develop a set of accurate biomarkers to be used as the standard of care and adapted to each stage of the disease.

Therapeutic effect of Shaoyao-Gancao Decoction on TLR9-mediated NETosis in MRL/lpr mice

Systemic lupus erythematosus (SLE) is a chronic, devastating autoimmune disorder associated with severe organ damage. The roles of Toll-like receptor 9 (TLR9) and NETosis in SLE have been described, suggesting the involvement of NETosis signaling in the development of SLE. Shaoyao-Gancao Decoction (SGT) is a potential medication for the treatment of SLE; however, its potential therapeutic mechanism remains unexplored. To determine the function of SGT in SLE, we treated MRL/lpr female mice with SGT, the main components of which were paeoniflorin (56.949 μg·mL-1) and glycyrrhizin (459.393 μg·mL-1). We found that SGT treatment relieved lymphadenectasis and splenomegaly, reduced urine protein and anti-dsDNA antibody concentrations, and relieved kidney pathology in MRL/lpr mice. SGT could also effectively regulate the oxidation/antioxidant balance, significantly reduce malondialdehyde (MDA) and nitric oxide (NO) contents and significantly increase superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in MRL/lpr mice. The neutrophil extracellular trap (NET) content of MRL/lpr mice also decreased to a certain extent after SGT treatment. All these results suggested that SGT might improve the inflammatory damage to tissues caused by oxygen free radicals, thereby regulating the NETosis process mediated by TLR9 and exerting a good therapeutic effect on SLE.

Real-world use of mycophenolate mofetil in inflammatory bowel disease: Results from the ENEIDA registry

BACKGROUND

Studies to evaluate the use of mycophenolate mofetil (MMF) in inflammatory bowel disease (IBD) are limited after the appearance of biological treatments.

AIMS

Our primary objective was to evaluate the effectiveness and safety of MMF in IBD.

METHODS

IBD patients who had received MMF were retrieved from the ENEIDA registry. Clinical activity as per the Harvey-Bradshaw Index (HBI), partial Mayo score (pMS), physician global assessment (PGA) and C-reactive protein (CRP) were reviewed at baseline, at 3 and 6 months, and at final follow-up. Adverse events and causes of treatment discontinuation were documented.

RESULTS

A total of 83 patients were included (66 Crohn's disease, 17 ulcerative colitis), 90% of whom had previously received other immunosuppressants. In 61% of patients systemic steroids were used at initiation of MMF, and in 27.3% biological agents were co-administered with MMF. Overall clinical effectiveness was observed in 64.7% of the population. At the end of treatment, 45.6% and 19.1% of subjects showed remission and clinical response, respectively. MMF treatment was maintained for a median of 28.9 months (IQR: 20.4-37.5).

CONCLUSION

Our study suggests, in the largest cohort to date, that MMF may be an effective alternative to thiopurines and methotrexate in IBD.

A pharmacoeconomic study comparing the use of mycophenolate mofetil or cyclophosphamide as induction therapy in lupus nephritis patients in Egypt

INTRODUCTION/OBJECTIVES

Lupus nephritis (LN) is a major and serious complication of systemic lupus erythematosus (SLE) and is associated with morbidity and mortality. The difference in drug cost between mycophenolate mofetil (MMF) and cyclophosphamide (CYC) inducing regimens becomes a relevant and realistic issue, especially in developing countries. Thus, this study aims to estimate and compare the costs and outcomes of CYC and MMF for better allocation of resources to reduce the burden on the Egyptian healthcare system.

METHODS

A prospective, parallel observational study was conducted at Kasr Al-Aini Hospital between 2018 and 2020. One hundred and twenty-two LN patients were followed up monthly during the study period. Remission and maintenance of renal remission were assessed at 6 and 12 months from the start of therapy. Total direct medical costs associated with both regimens were examined. We applied the cost-minimization analysis method from governmental perspective. Besides, a prospective evaluation of reported changes in health-related quality of life using SF-36 was included in our study.

RESULTS

There was no statistically significant difference in treatment response at 6 and 12 months (RR 0.6 [0.26;1.43] and 0.8 [0.27;2.33]), respectively, as well as the incidence of infection episodes between MMF and CYC group (71.4% versus 70.45%, p > 0.05). The average direct medical expenditures per patient in the MMF group were approximately one and half times more than the CYC group (2339.69 $ versus 1329.03 $, p <0.001).

CONCLUSION

The CYC arm was associated with lower costs than the MMF arm, with equally effective outcomes indicating that CYC is an attractive treatment option.

Comparison of Renal Responses Between Continuous Mycophenolate Mofetil and Conversion from Mycophenolate Mofetil to Enteric-Coated Mycophenolate Sodium in Lupus Nephritis

BACKGROUND

Mycophenolate mofetil (MMF) is extensively used for induction and maintenance therapy in patients with lupus nephritis (LN). Enteric-coated mycophenolate sodium (EC-MPS) was developed to reduce the adverse gastrointestinal effects of MMF. However, the therapeutic efficacy of MMF and EC-MPS in LN remains unclear. This study aimed to examine the treatment effects of EC-MPS in LN patients with prior MMF exposure.

METHODS

In this medical records review study, we included 54 LN patients, of whom 34 converted from MMF to EC-MPS at equimolar doses in 2016-2018 (nonmedical switching group) and 20 received continuous MMF treatment. Patients achieving complete remission or partial remission before the conversion were categorized as responders, whereas those who had never achieved complete remission or partial remission were categorized as nonresponders.

RESULTS

Baseline proteinuria was higher in the nonmedical switching group. Although elevation in proteinuria was observed after nonmedical switching, the serum creatinine concentration and estimated glomerular filtration rate both improved. Responders in the nonmedical switching group had lower proteinuria and higher complement 3 levels. In the subgroup analysis, albeit the modest increase in daily urine protein, anti-double-stranded DNA antibody levels, estimated glomerular filtration rate, and complements 3 and 4 seemed comparable after conversion.

CONCLUSION

Switching to EC-MPS demonstrated a similar short-term renal response to continuous MMF treatment in LN patients. Prospective randomized trials are required to verify our findings.

Real-World Experience of Safety of Mycophenolate Mofetil in 119 Japanese Patients with Systemic Lupus Erythematosus: A Retrospective Single-Center Study

Objectives

Mycophenolate mofetil (MMF) is the standard treatment for lupus nephritis. In Japan, it was approved for lupus nephritis in 2015. We investigated its real-world safety and effectiveness in Japanese patients with systemic lupus erythematosus (SLE).

Methods

We analyzed the continuation rate, adverse events, and reasons for discontinuation of MMF in Japanese patients with SLE in a retrospective single-center study. We included 119 patients who received MMF from 31 July 2015 to 31 May 2019. To compare demographic and clinical characteristics between groups, the Mann–Whitney U-test was used for nonnormally distributed variables. Categorical variables were compared using Fisher's exact test. Kaplan–Meier curves were plotted for the discontinuation rate of MMF.

Results

Patients consisted of 18 males and 101 females. Thirty-five patients discontinued MMF. The cumulative discontinuation rate was 42.4%. Twenty-nine patients discontinued MMF due to adverse events, and six patients discontinued MMF due to remission of SLE or desire for childbearing. At the time of the last observation, the lupus low disease activity state achievement rate was significantly lower in patients who experienced adverse events than those who did not (64% vs. 35%, P = 0.009). We examined the concentration of mycophenolate acid (trough level) in stored frozen serum in 11 patients. Two patients had irreversible complications due to viral meningitis; their trough mycophenolate acid concentrations were 8.3 and 6.3 μg/mL, respectively.

Conclusions

Although MMF may be effective in Japanese patients with SLE, physicians should pay attention to infections in patients with high mycophenolate acid concentrations.

Mycophenolic acid, the active form of mycophenolate mofetil, interferes with IRF7 nuclear translocation and type I IFN production by plasmacytoid dendritic cells

BACKGROUND

Both humoral and cellular immune mechanisms are involved in the onset and progression of autoimmune responses in systemic lupus erythematosus (SLE). Plasmacytoid dendritic cells (pDCs) play a central role in the pathogenesis of SLE via the dysregulation of type I interferon (IFN) production; these cells act together with activated myeloid DCs (mDCs) to amplify the vicious pathogenic spiral of autoimmune disorders. Therefore, control of aberrant DC activation in SLE may provide an alternative treatment strategy against this disease. Mycophenolate mofetil (MMF), which has been used to treat lupus nephritis, specifically blocks the proliferation of B and T lymphocytes via inhibition of inosine-5-monophosphate dehydrogenase. Here, we focus on the effects of MMF in targeting DC functions, especially the IFN response of pDCs.

METHODS

We isolated human blood pDCs and mDCs by flow cytometry and examined the effect of mycophenolic acid (MPA), which is a metabolic product of MMF, on the toll-like receptor (TLR) ligand response of DC subsets. Additionally, we cultured pDCs with serum from SLE patients in the presence or absence of MPA and then examined the inhibitory function of MPA on SLE serum-induced IFN-α production.

RESULTS

We found that treatment with 1-10 μM of MPA (covering the clinical trough plasma concentration range) dose-dependently downregulated the expression of CD80 and CD86 on mDCs (but not pDCs) without inducing apoptosis, in response to R848 or CpG-ODN, respectively. Notably, in pDCs, MPA significantly suppressed IFN-α production with IRF7 nuclear translocation and repressed the AKT activity. In addition, MPA inhibited IL-12 production with STAT4 expression in mDCs. We further identified that MPA had an inhibitory effect on SLE serum-induced IFN-α production by pDCs.

CONCLUSIONS

Our data suggest that MPA can interrupt the vicious pathogenic spiral of autoimmune disorders by regulating the function of DC subsets. This work unveiled a novel mechanism for the therapeutic ability of MMF against SLE.

Evaluation of treatment with a combination of mycophenolate mofetil and prednisolone in dogs with meningoencephalomyelitis of unknown etiology: a retrospective study of 86 cases (2009-2017)

BACKGROUND

Combination therapy with glucocorticoids and adjunctive immunomodulating drugs has been generally accepted as a standard treatment regimen for meningoencephalomyelitis of unknown etiology (MUE). We hypothesized that treatment with MMF as an adjunctive agent along with glucocorticoids would be effective and well-tolerated protocol in dogs with MUE. Eighty-six dogs with MUE between May 2009 and June 2017 were included (59 females and 27 males; mean age of 5.93 years; mean body weight of 3.83 kg). The medical records of dogs with MUE treated with prednisolone and MMF were retrospectively evaluated to determine the therapeutic response, survival time, and treatment-related adverse effects.

RESULTS

A partial or complete response (CR) was recorded for 75 dogs. The overall median survival time from the initiation of treatment was 558 days. Dogs that showed CR with no relapse over the treatment period (from diagnosis to death) had significantly longer median survival times. A significantly higher mortality hazard ratio of 4.546 was recorded in dogs that failed to achieve CR. The interval between the onset of clinical signs and the clinical presentation was not significantly associated with CR, relapse rate, and survival time. Adverse effects included gastrointestinal upsets in 26 dogs (30.23%), sporadic infections in 17 dogs (19.77%), and pancreatitis in seven dogs (8.14%).

CONCLUSIONS

The results suggest that adjunctive MMF treatment for MUE is safe and comparable to other immunosuppressive protocols. The treatment should focus on the achievement of CR and preventing relapse for successful management.

Drug repurposing to improve treatment of rheumatic autoimmune inflammatory diseases

The past century has been characterized by intensive efforts, within both academia and the pharmaceutical industry, to introduce new treatments to individuals with rheumatic autoimmune inflammatory diseases (RAIDs), often by 'borrowing' treatments already employed in one RAID or previously used in an entirely different disease, a concept known as drug repurposing. However, despite sharing some clinical manifestations and immune dysregulation, disease pathogenesis and phenotype vary greatly among RAIDs, and limited understanding of their aetiology has made repurposing drugs for RAIDs challenging. Nevertheless, the past century has been characterized by different 'waves' of repurposing. Early drug repurposing occurred in academia and was based on serendipitous observations or perceived disease similarity, often driven by the availability and popularity of drug classes. Since the 1990s, most biologic therapies have been developed for one or several RAIDs and then tested among the others, with varying levels of success. The past two decades have seen data-driven repurposing characterized by signature-based approaches that rely on molecular biology and genomics. Additionally, many data-driven strategies employ computational modelling and machine learning to integrate multiple sources of data. Together, these repurposing periods have led to advances in the treatment for many RAIDs.

Management of refractory lupus nephritis: challenges and solutions

Refractory lupus nephritis, broadly defined as failure to attain clinical remission after appropriate induction immunosuppressive therapy, is associated with an increased risk of progression to end-stage kidney disease and mortality. This is a challenging issue in clinical practice, as modern induction therapy despite proven efficacy can still be associated with treatment failure. Moreover, newer therapies have failed in recent years to displace or even match existing protocols for effective induction of remission. Refractory disease is generally assessed on the basis of clinical parameters, which may be unreliable, and renal biopsy, which is often not performed in a standard or timely fashion. Persisting histological inflammation in 30%–50% of patients who have attained clinical remission highlights the disparity between clinical and immunological response to therapy. The lack of an international consensus regarding what constitutes refractory lupus nephritis compounds clinician indecision regarding optimal management for these patients. Moreover, non-adherence to prescribed therapy versus primary treatment failure can be challenging to discriminate, and the time point at which non-response becomes treatment failure is unclear. In this review, we assess the key published evidence for the treatment of refractory lupus nephritis and provide practical recommendations based around the use of adjunctive therapies. These agents include rituximab and calcineurin inhibitors, with evidence consisting largely of observational or uncontrolled studies, as well as some of the biologic therapies currently under investigation through prospective clinical trials. The poor prognosis of refractory lupus nephritis demands regular review of patient response and the flexibility to switch or augment therapy.

Cryptotanshinone ameliorates the pathogenesis of systemic lupus erythematosus by blocking T cell proliferation

Systemic lupus erythematosus (SLE) is a chronic, devastating autoimmune disorder associated with severe organ damage. Recently, the role of Signal Transducer and Activator of Transcription 3 (STAT3) in murine lupus has been described, suggesting the involvement of STAT3 signaling in the development of SLE. Cryptotanshinone (CTS) is an effective inhibitor of STAT3; however its potential as a SLE treatment remains to be explored. To determine the function of CTS in SLE, we treated MRL/lpr female mice with CTS. Firstly, we found CTS treatment reversed the elevated STAT3 signaling of spleens in lupus-prone MRL/lpr mice, accompanying with a dramatically decreased number of T cells, especially double-negative (DN) T cells. Further research showed that CTS inhibited T cell proliferation via suppressing of STAT3 activation in vitro and in vivo. Consistently, we also proved that CTS treatment significantly alleviated autoimmune response including notably diminished skin lesions, reduced spleen size and increased life span. In addition, CTS treatment decreased the levels of auto-antibodies and pro-inflammatory cytokines, as well as normalized structure and function of kidneys. All these data suggested that CTS treatment depressed STAT3 phosphorylation, which resulted in blocked DN T cell proliferation and finally attenuated the spontaneous SLE development. Taken together, our data identify CTS as a potential therapeutic drug for SLE patients.

[Lupus nephritis]

Systemic lupus erythematosus is the most characteristic of auto-immune disorders that can lead to tissue damage in many organs, including kidney. Lupus nephritis occurs in 10 to 40% of lupus patients. Its clinical hallmark is the appearance of a proteinuria as soon as a 0.5 g/g or 0.5 g/d threshold, which calls for a renal histological evaluation in order to determine the lupus nephritis severity and the need for specific therapy. More than half of renal biopsies lead to the diagnosis of active lupus nephritis-class III or class IV A according to the ISN/RPS classification-that are the most severe in regards to renal prognosis and mortality. Their treatment aims to their clinical remission and to the prevention of relapse with minimal adverse effects for eventually the preservation of renal function, the prevention of other irreversible damage, and the reduction of risk of death. The remission is obtained through induction therapies of which the association of high dose steroids and cyclophosphamide is the most experienced. When this association must be challenged by the prevention of side-effect, in particular infertility, mycophenolate can be given instead of cyclophosphamide. Maintenance therapy, for the prevention of relapse, consists in mycophenolate or in azathioprine, mycophenolate being the most efficient however associated with a high risk of teratogenicity. Withdrawal of maintenance therapy is possible after two to three years in absence of high risk factors of relapse of lupus nephritis, however a reliable assessment of the risk of relapse is still lacking. Only pure membranous lupus nephritis (pure class V) associated with high level proteinuria requires specific therapies that usually associates steroids and an immunosuppressive drug. However, their choice hierarchy and even the use of less immunosuppressive strategies remain to be determined in terms of benefice over risk ratios. In spite of its trigger effect on lupus activity, pregnancy can be safe and successful if scheduled in the lowest risk periods with close multidisciplinary monitoring before, during and after. When necessary, renal replacement therapy does not require specific adaptation, renal transplantation is the best option when possible, as early as possible.

Current status of lupus nephritis

Systemic lupus erythematosus (SLE) is a systemic disease of unknown aetiology with variable course and prognosis. Lupus nephritis (LN) is one of the important disease manifestations of SLE with considerable influence on patient outcomes. Immunosuppression therapy has made it possible to control the disease with improved life expectancy and quality of life. In the last few decades, various studies across the globe have clarified the role, dose and duration of immunosuppression currently in use and also provided evidence for new agents such as mycophenolate mofetil, calcineurin inhibitors and rituximab. However, there is still a need to develop new and specific therapy with less adverse effects. In this review, the current evidence of the treatment of LN and its evolution, and new classification criteria for SLE have been discussed. Also, rationale for low-dose intravenous cyclophosphamide as induction agent followed by azathioprine as maintenance agent has been provided with emphasis on individualized and holistic approach.

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).

Immunosuppression With Mycophenolate Mofetil Attenuates Hypertension in an Experimental Model of Autoimmune Disease

Background

Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder that predominantly affects women and is associated with prevalent hypertension, renal injury, and cardiovascular disease. Immune system dysfunction is recognized as an important factor in the pathogenesis of hypertension. We recently showed that preventing autoimmunity prevents the development of hypertension in an experimental model of SLE (female NZBWF1 mice). The present study tests the hypothesis that mycophenolate mofetil (MMF), an immunosuppressive therapy used clinically to treat SLE by depleting proliferating B and T lymphocytes, can improve blood pressure control.

Methods and Results

Female SLE and control (NZW/LacJ) mice were treated daily for 8 weeks with 60 mg/kg MMF. Circulating CD45R⁺ B cells were lower in MMF‐treated SLE mice after 4 weeks of treatment, but neither CD4⁺ nor CD8⁺ T cells were reduced by MMF. Plasma anti–double‐stranded DNA IgG autoantibodies, a marker of SLE disease activity, were higher in SLE mice compared with controls and were lower in SLE mice after 8 weeks of MMF. Mean arterial pressure was elevated in SLE mice compared with controls and lower in SLE mice treated with MMF compared with vehicle‐treated SLE mice. MMF also reduced both renal injury (urinary albumin excretion and glomerulosclerosis) and the infiltration of CD45R⁺ B cells and CD3⁺CD4⁺ T cells in kidneys from mice with SLE.

Conclusions

These data suggest that MMF selectively depleted CD45R⁺ B cells and lowered subsequent autoantibody production, furthering the concept that autoantibodies mechanistically contribute to the pathogenesis of hypertension.

Mycophenolate Mofetil and Systemic Lupus Erythematosus: An Overview

Mycophenolate mofetil (MMF) is an immunosuppressive agent used in transplantation, with evidence of superior protection against acute transplant rejection compared to azathioprine-containing regimens. Subsequently MMF has been used in a variety of autoimmune conditions. The major experience in systemic lupus erythematosus (SLE) has focused on proliferative lupus nephritis. Following its success in the treatment of lupus nephritis, MMF is now being used to control other SLE manifestations such as, lupus disease activity, haematological manifestations and resistant skin lupus. In this review, we discuss our own experience and the literature report about the use of MMF in SLE.

Lupus Nephritis: Induction Therapy

Effective induction therapy is of pivotal importance in minimizing renal parenchymal damage by the active immune-mediated inflammatory processes in severe proliferative lupus nephritis. Preservation of nephron mass is prerequisite to long-term renal survival. Data from US-based studies have shown improved efficacy with induction treatment comprising corticosteroid and cyclophosphamide, compared with corticosteroid treatment alone. Data from European studies have shown similar efficacy with a modified treatment regimen, in which smaller doses of cyclophosphamide were given at weekly or fortnightly intervals over a shortened treatment duration, and the treatment related adverse effects appeared less frequent with the reduced-dose regimen. We have also reported that sequential immunosuppression with prednisolone and oral cyclophosphamide as induction followed by azathioprine maintenance was associated with a high incidence of remission and relatively favourable long-term renal outcome in Chinese patients. However, cyclophosphamide treatment is associated with considerable adverse effects, which could be potentially fatal. Mycophenolate mofetil selectively inhibits lymphocyte proliferation, and thus targets an instrumental step in the pathogenesis of systemic lupus erythematosus. There is accumulating evidence that the combined use of mycophenolate mofetil and corticosteroid presents an effective treatment for severe proliferative lupus nephritis in different ethnic groups, and is associated with much fewer adverse effects compared with cyclophosphamide-based regimens. Recent data from our group also demonstrate the long-term efficacy of mycophenolate mofetil in preserving renal survival, when used continuously as both induction and maintenance therapy.

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 and systemic lupus erythematosus: an overview

Mycophenolate mofetil (MMF) is an immunosuppressive agent used in transplantation, with evidence of superior protection against acute transplant rejection compared to azathioprine-containing regimens. Subsequently MMF has been used in a variety of autoimmune conditions. The major experience in systemic lupus erythematosus (SLE) has focused on proliferative lupus nephritis. Following its success in the treatment of lupus nephritis, MMF is now being used to control other SLE manifestations such as, lupus disease activity, haematological manifestations and resistant skin lupus. In this review, we discuss our own experience and the literature report about the use of MMF in SLE.

Mycophenolate mofetil and systemic lupus erythematosus

Mycophenolate mofetil (MMF) is an immunosuppressive agent which provides protection against acute transplant rejection, in patients who undergo kidney, heart and liver transplantation. Recently MMF has been used in various autoimmune conditions, including systemic lupus erythematosus (SLE). In SLE, MMF has been more extensively used in the treatment of proliferative lupus glomerulonephritis (GLN) and following the success in this field, it has also been used to control extra-renal manifestations. However, in the majority of cases MMF was administered to patients with refractory SLE manifestations and, therefore, no definite conclusion could be drawn from these experiences.

In this paper, after a brief description of the mechanisms of action, the pharmacokinetics and metabolism of MMF which are relevant in SLE, and after a short discussion on the utility of performing therapeutic dose monitoring of mycphenolic acid, the experiences with the use of this drug in the different SLE manifestations were summarized and some personal data in patients with GLN were reported. Finally, the hypothetical use of MMF as a preventive strategy against the occurrence of severe manifestations in patients with mild SLE has been put forward and discussed.

Mycophenylate mofetil: what role in the treatment of lupus?

Improved patient survival following lupus nephritis with the institution of corticosteroids, immunosuppressants and renal replacement therapy allows greater emphasis on long-term management issues. In particular, the recent focus has been on therapies to treat nephritis with fewer adverse effects of cyclophosphamide-including immunosuppressive regimens. Mycophenolate mofetil (MMF) has been used in the field of transplantation for more than 10 years. Following initial anecdotal reports describing benefits of MMF in the treatment of lupus nephritis, randomized, controlled trials have established a role for MMF in the treatment of lupus nephritis. MMF use to treat other lupus manifestations has been evaluated only in anecdotal case reports or series with few well-designed trials. Issues complicating clinical trial design in lupus including appropriate use and interpretation of activity and damage indices, comparable remission and response criteria and stratification of high risk populations have been the subject of much discussion and emerging consensus. As long-term outcomes in lupus improve, the toxicity of therapy and risk of relapse become increasingly important determinants of choice of therapeutic agents.

Hypertension and Afro-descendant ethnicity: a bad interaction for lupus nephritis treated with cyclophosphamide?

Hypertension and ethnicity are important prognostic factors in evolution of lupus nephritis. A cohort of 75 patients with lupus nephritis treated with cyclophosphamide was conducted to investigate the evolution of creatinine levels between Caucasians and Afro-descendants. A multiple linear model was used to evaluate the combined effects of ethnicity and hypertension over delta creatinine controlling confounders. Sample characteristics were: 85% females; mean (±SD) age of 33.6 ± 12.0 years; 77% Caucasians; 40% hypertensive at renal biopsy; 91% WHO class IV; mean basal creatinine: 1.5 ± 1.3 mg/dL; mean final creatinine: 2.1 ± 2.5 mg/dL; 40% anaemia; proteinuria: 5.4 ± 4.8 g/day. Comparing Caucasians and Afro-descendants, it was found: 28.1% versus 72.2% for hypertension ( P = 0.002); 31.6% versus 66.7% for anaemia ( P = 0.018); 5.9 ± 5.0 versus 3.8 ± 4.0. g/day ( P = 0.02) for proteinuria. Other comparisons including basal creatinine did not reach statistical significance. Comparing outcomes between Caucasians and Afro-descendants, it was found: 10.5% versus 22.2% for doubling of creatinine ( P = 0.24); 0.41 ± 2.03 versus 1.05 ± 2.41 for delta creatinine ( P = 0.29); 8.8% versus 22.2% for haemodialysis ( P = 0.21) and 3.5% versus 5.6% for death ( P = 0.99). Analysing delta creatinine with multiple linear regression showed that hypertension had a significant overall effect ( b = 0.80; SE = 0.32; P = 0.015), ethnicity alone was not significant ( b = 0.35; SE = 0.29; P = 0.228); however, the effect of hypertension on delta creatinine was more intense among Afro-descendants than among Caucasians (interaction term b = — 0.83; SE = 0.37; P = 0.027). Afro-descendants lupus patients experience worst prognosis of renal function probably due to the effect of hypertension and not ethnicity per se. Lupus (2007) 16, 724—730.

Relapse with transformation of lupus nephritis in a transplant kidney

Lupus nephritis is a constellation of different renal histologies, characterized by an immune complex mediated glomerular disease. Histological transformation in lupus nephritis usually occurs from a mild mesangial proliferative glomerulonephritis to a more aggressive diffuse proliferative lesion. We present a case of relapsed systemic lupus erythematosus (SLE) in a renal transplant recipient in which there was a histological transformation from the original diffuse proliferative lupus nephritis in the native kidneys to a membranous lupus nephritis in the renal transplant.

Mycophenolate mofetil combined with prednisone for diffuse proliferative lupus nephritis: a histopathological study

Mycophenolate mofetil (MMF) is a potential new treatment for diffuse proliferative lupus nephritis. This study examines the clinical and histopathological effects, and potential mechanisms, of combination MMF/prednisone therapy in diffuse proliferative lupus nephritis. Nine patients with diffuse proliferative lupus nephritis confirmed by renal biopsy received MMF/prednisone for six months when repeat biopsies were performed. Clinical and histopathological parameters of activity and chronicity were studied. Collagens were detected by Sirus red staining; leucocyte phenotype, osteopontin (OPN), fibrinectin (FN), a-smooth muscle actin (a-SMA) and TGF-b1 were detected by immunohistochemistry. The changes of clinical and histopathologic parameters were assessed and compared to histopathologic indicators. Eight of the nine patients achieved clinical remission; renal function deteriorated in one. Histopathological activity indices reduced significantly (9.56 + 2.83 versus 5.22 + 1.86, P < 0.01); however, the chronicity indices did not change (3.56 + 1.42 versus 3.22 + 1.20). T-cell and monocyte/macrophage infiltration, OPN expression and the percentage of proliferative cells in both glomerulus and tubulo-interstitiumdecreased significantly. Other features of chronic lesions, except for glomerular collagen deposition, did not change. In conclusion, MMF/prednisone therapy was effective for our patients with proliferative lupus nephritis. The active inflammatory lesions could be ameliorated through reduction of lymphocyte and monocyte/macrophage infiltration, inhibition of cell proliferation and downregulation of adhesive molecules. However, the chronic fibrotic lesions could not be significantly reduced.

Microangiopathic haemolytic anaemia secondary to lupus nephritis: an important differential diagnosis of thrombotic thrombocytopenic purpura

Systemic lupus erythematosus (SLE) has been described as a cause of microangiopathic haemolytic anaemia (MAHA), however there is little literature to support this assertion. We report on three patients presenting with SLE and MAHA with a clinical picture indistinguishable from thrombotic thrombocytopenic purpura (TTP), who had underlying lupus nephritis. They all had significant proteinuria and normal Von Willebrand Factor cleaving protease (vWF-CP) levels. Their MAHA fitted better for haemolytic syndrome (HUS) and their cerebral signs were explained either by malignant hypertension or cerebral lupus. Their MAHA only improved when the appropriate treatment for lupus nephritis was given.

We propose that the previously described association between SLE and MAHA, in actuality relates to the underlying presence of lupus nephritis causing haemolytic uraemic syndrome, not TTP. Significant proteinuria was present in all cases of MAHA due to lupus nephritis, so may be a useful discriminatory sign. Furthermore the demonstration of a normal vWF-CP assay aided in the distinction between TTP and MAHA due to lupus nephritis. All our patients responded to mycophenolate mofetil suggesting this may be useful in other cases of lupus nephritis causing HUS. Lupus (2007) 16, 358—362.

Modulation of intra-pulmonary TGF-b expression by mycophenolate mofetil in lupus prone MRL/lpr mice

We investigated the expression profile of inflammatory cytokines in the lung of lupus-prone MRL/lpr mice and evaluated the therapeutic potential of mycophenolate mofetil (MMF) in reducing pulmonary cytokines in active lupus. Eight-week old female MRL/lpr mice ( n = 20) were treated with MMF in vehicle by oral gavage. Disease control MRL/lpr mice ( n = 30) or normal control MRL mice ( n = 20) received vehicle alone. The mice were sacrificed after eight or 12 weeks of treatment. Gene expression and protein synthesis of IL-1β, MCP-1 and TGF-β1 in lung tissues were determined. We found an increase in the gene expression of IL-1β, MCP-1 and TGF-β1 in lung tissues of untreated MRL/lpr mice compared with MRL mice at either 16 weeks or 20 weeks of age. MMF treatment significantly prolonged the survival of MRL/lpr mice, down-regulated the gene expression of IL-1β, MCP-1 and TGF-β1 in lung tissues at the end of eight or 12 weeks of treatment. Protein synthesis of TGF-b1 was decreased following eight weeks of MMF treatment. We conclude that MMF treatment can reduce the TGF-b1 gene expression and protein synthesis in lung tissues of lupus-prone mice. Our findings provide experimental data suggesting a beneficial potential of MMF therapy in pulmonary involvement of lupus.

A multicentre, randomised controlled study of enteric-coated mycophenolate sodium for the treatment of relapsed or resistant proliferative lupus nephritis: an Asian experience

Objective

The optimal treatment of relapse or resistant lupus nephritis (LN) is still unclear. Mycophenolate might be an alternative therapy to avoid toxicities of cyclophosphamide (CYC). This study was aimed to compare enteric-coated mycophenolate sodium (EC-MPS) versus intravenous CYC as an induction therapy.

Methods

The study was a 12-month period of multicentre, open-labelled randomised controlled trial. Fifty-nine patients who had relapsed (36%) or who were resistant to previous CYC treatment (64%) and all who were biopsy-proven class III/IV, were randomised into CYC (n=32) and EC-MPS groups (n=27). The CYC group received intravenous CYC 0.5–1 g/m² monthly and the EC-MPS group was treated with EC-MPS 1440 mg/day for first 6 months. After induction therapy, both groups received EC-MPS 720 mg/day until the end of study at 12 months.

Results

The study was prematurely terminated due to high rate of serious adverse events in CYC arm. Death and serious infections were observed more in the CYC group (15.6% in CYC and 3.5% in EC-MPS; p=0.04). The early discontinuation rates, mainly from serious infections, were significantly higher in CYC group (percentage differences of 16.9; 95% CI 1.3 to 32.4). At the 12th month, both arms were comparable in terms of complete and partial remission rates (68% CYC and 71% EC-MPS) and times to remission (96 days CYC and 97 days EC-MPS). Composites of unfavourable outcomes (death, doubling of serum creatinine, non-remission and intolerance to treatment) were 46.9% and 37% in CYC and EC-MPS (risk difference=9.84; p=0.44).

Conclusions

EC-MPS may have comparable efficacy, but was better tolerated than CYC. EC-MPS should be an alternative choice of treatment for difficult-to-treat LN, particularly in CYC-experienced LN patients. Due to an early termination of the study, further clinical implementation could be cautiously used.

Trial registration number

Clinicaltrials.gov ID#NCT01015456.

Mycophenolate Mofetil Modulates Differentiation of Th1/Th2 and the Secretion of Cytokines in an Active Crohn's Disease Mouse Model

Mycophenolate mofetil (MMF) is an alternative immunosuppressive agent that has been reported to be effective and well tolerated for the treatment of refractory inflammatory bowel disease (IBD). The aim of this study was to investigate the therapeutic effect of MMF on intestinal injury and tissue inflammation, which were caused by Crohn’s disease (CD). Here, trinitrobenzene sulfonic acid-relapsing (TNBS) colitis was induced in mice; then, we measured the differentiation of Th1/Th2 cells in mouse splenocytes by flow cytometry and the secretion of cytokines in mice with TNBS-induced colitis by real-time polymerase chain reaction and/or enzyme-linked immunosorbent assay (RT-PCR/ELISA). The results show that MMF significantly inhibited mRNA expression of pro-inflammatory cytokines IFN-γ, TNF-α, IL-12, IL-6, and IL-1β in mice with TNBS-induced colitis; however, MMF did not inhibit the expression of IL-10 mRNA. Additionally, ELISA showed that the serum levels of IFN-γ, TNF-α, IL-12, IL-6, and IL-1β were down-regulated in a TNBS model of colitis. Flow cytometric analysis showed MMF markedly reduced the percentages of Th1 and Th2 splenocytes in the CD mouse model. Mycophenolic acid (MPA) also significantly decreased the percentages of splenic Th1 and Th2 cells in vitro. Furthermore, MMF treatment not only significantly ameliorated diarrhea, and loss of body weight but also abrogated the histopathologic severity and inflammatory response of inflammatory colitis, and increased the survival rate of TNBS-induced colitic mice. These results suggest that treatment with MMF may improve experimental colitis and induce inflammatory response remission of CD by down-regulation of pro-inflammatory cytokines via modulation of the differentiation of Th1/Th2 cells.

The multifaceted aspects of refractory lupus nephritis

The term refractory lupus nephritis is generally used to indicate cases that do not respond to traditional treatment. However, the clinical presentation of lupus nephritis is variable and the time to response depends on the typology of the underlying renal syndrome. The criteria and the time for response are different in lupus patients with nephritic flares, in those with nephrotic syndrome, and in those with asymptomatic renal disease. In this paper, we will focus on the clinical characteristics, the consequences, and the possible therapeutic approaches for patients with different forms of refractory lupus nephritis, defined on the basis of renal syndrome at presentation.

Mycophenolate mofetil in the treatment of SLE and systemic vasculitis: experience at a single university center

Mycophenolate mofetil (MMF) is used off-label for systemic lupus erythematosus (SLE) and systemic vasculitis. The study aim was to investigate clinical use and treatment results with MMF in patients with SLE and systemic vasculitis. This study included patients with SLE or systemic vasculitis with ongoing or previous MMF treatment. Data on treatment outcome were obtained through medical record reviews. A total of 135 of 648 (21%) patients with SLE and 43 of 455 (9%) patients with systemic vasculitis had ongoing or previous MMF treatment. Among SLE patients, the most common organ manifestation at baseline (treatment start) was renal involvement (50%). Most of the systemic vasculitis patients had Wegener’s granulomatosis (GPA) (65%). Median dose of MMF was 2000 mg/day. Glucocorticoid (GC) doses were significantly reduced during MMF treatment from 21.7 mg/day at baseline to 8.3 mg/day at 12 months ( p < 0.05). Forty-six percent of the patients were good responders after 12 months. The most common adverse events (AES) leading to discontinuation were side effects in the gastrointestinal tract (40%) and general side effects (30%). “Survival-on-drug” analysis suggested that 40% of the patients remained on long-term MMF treatment. In conclusion, MMF was used in 21% of the SLE patients and 9% of the systemic vasculitis patients. MMF appeared to be effective with a reasonable survival-on-drug and a GC-sparing effect.

WITHDRAWN: Use of mycophenolic acid in lupus nephritis

Due to overlap of certain parts of text of our review 'Use of mycophenolic acid in lupus nephritis' with the previously published review by Zizzo, Ferraccioli and Santis, 'Mycophenolic acid in rheumatology: mechanisms of action and severe adverse events' (Reumatismo. 2010; 62(2):91-100), we request that our review is retracted with apologies to Drs. Zizzo, Ferraccioli and Santis, the editors and the readers. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

Generation of gene-engineered chimeric DNA molecules for specific therapy of autoimmune diseases

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the development of self-reactive B and T cells and autoantibody production. In particular, double-stranded DNA-specific B cells play an important role in lupus progression, and their selective elimination is a reasonable approach for effective therapy of SLE. DNA-based vaccines aim at the induction of immune response against the vector-encoded antigen. Here, we are exploring, as a new DNA-based therapy of SLE, a chimeric DNA molecule encoding a DNA-mimotope peptide, and the Fv but not the immunogenic Fc fragment of an FcγRIIb-specific monoclonal antibody. This DNA construct was inserted in the expression vector pNut and used as a naked DNA vaccine in a mouse model of lupus. The chimeric DNA molecule can be expressed in eukaryotic cells and cross-links cell surface receptors on DNA-specific B cells, delivering an inhibitory intracellular signal. Intramuscular administration of the recombinant DNA molecule to lupus-prone MRL/lpr mice prevented increase in IgG anti-DNA antibodies and was associated with a low degree of proteinuria, modulation of cytokine profile, and suppression of lupus nephritis.

Efficacy of mycophenolate mofetil in adolescent patients with lupus nephritis: evidence from a two-phase, prospective randomized trial

The safety and efficacy of mycophenolate mofetil (MMF) were evaluated in adolescent patients with systemic lupus erythematosus and active or active/chronic class III–V lupus nephritis. During the 24-week induction phase, patients were randomized to oral MMF (target dose 3.0 g/day) or intravenous cyclophosphamide (IVC) (0.5–1.0 g/m2/month), plus prednisone. Response was defined as a decrease in 24-hour urine protein:creatinine ratio (P:Cr) to <3 in patients with baseline nephrotic range proteinuria, or by ≥50% if subnephrotic baseline proteinuria, and stabilization (±25%) or improvement in serum creatinine. In the 36-month maintenance phase, induction therapy responders were randomized 1:1 to MMF (1.0 g twice daily) or oral azathioprine (AZA) (2 mg/kg/day), plus prednisone. In the induction phase, 10 patients received MMF and 14 received IVC; 15 (62.5%) achieved treatment response (MMF, 7 (70%); IVC, 8/15 (57.1%); p = 0.53, odds ratio (95% confidence interval) 2.0 (0.2, 15.5)). There was a non-statistically significant difference in maintenance of response to MMF (7/8; 87.5%) versus AZA (3/8; 37.5%). Seven patients withdrew (MMF, 2; AZA, 5). During both phases, rates of serious adverse events were similar in both arms. During both phases treatment response with MMF was as effective as the comparator.

Clinical features and renal outcome in lupus patients with diffuse crescentic glomerulonephritis

The objectives of the study are to investigate the clinical features and renal outcomes in lupus patients with diffuse crescentic glomerulonephritis (DCGN). Ninety-four DCGN lupus patients were enrolled. Their clinical features and renal outcomes were investigated. There were 84 females and 10 males, with a mean age of 27.9 ± 10.7 years old. They represented: hypertension in 73 cases (77.7%), rapidly progressive glomerulonephritis in 62 cases (66.0%), 46 cases (48.9%) with nephritic syndrome, 35 (37.2%) gross hematuria, and 14 cases (14.9%) with uremic syndrome needed dialysis therapy. There were 25 cases received repeated renal biopsy. Their histological examination showed the decreasing of active lesions and the increasing chronic lesions. All patients were more than 6 months follow-up, and 79 patients (84.0%) were more than 12 months follow-up. At the first time of follow-up (3 months), the renal function, proteinuria, and anemia were improved significantly in all of cases received intensive immunosuppressive therapy. At the last time of follow-up (56.1 ± 18.8 months), only four patients eventually developed to the end-stage renal failure and five died with normal renal function. The lupus patients with DCGN presented more severe clinical syndromes, which were similar to those patients of type II of DCGN. The relative good renal outcomes were observed in those lupus patients, to which may be contribute to the effective induction therapy.

Management of systemic lupus erythematosus in Chinese patients

Systemic lupus erythematosus (SLE) is a worldwide disease with prevalence figures ranging from nine to 130 per 100,000 individuals. SLE appears to be more prevalent in certain ethnic groups, such as the African-Americans, African-Caribbeans and Asians. The prevalence of SLE in Hong Kong Chinese was estimated to be 59 out of 100,000 (104/100,000 among women), which is mid-way between that of the Caucasians and African-Americans. Certain organ manifestations, such as lupus nephritis, are more common in Chinese than Caucasians. A recent prospective study reported that the cumulative incidence of renal disease within 5 years of diagnosis of SLE in Chinese patients was 60%. Despite the improvement in survival of SLE in the past few decades, manifestations that are refractory to conventional therapies and treatment related complications are still major challenges in the management of SLE. Novel-therapeutic modalities for SLE should aim at targeting more specifically the immunopathogenetic pathways to achieve higher efficacy and reduce short- and long-term therapy-related toxicities. This review summarizes the management strategies and novel therapeutic modalities in SLE.

Combination therapy of mycophenolate mofetil and tacrolimus in lupus nephritis

Since most lupus nephritis patients have an incomplete response to mycophenolate mofetil, combination regimens may improve outcomes. Tacrolimus (FK506) has shown some benefit in lupus nephritis in small trials, and combined with mycophenolate mofetil is standard immunosuppression in transplant patients. We investigate the addition of FK506 to mycophenolate mofetil, in patients who were mycophenolate mofetil failures. All patients were part of a prospective cohort, but evaluated retrospectively. Seven lupus nephritis patients (mean age 27.1, 100% female, 42% Caucasian and 42% African American) were evaluated. Three patients had combined ISN class III and V, two ISN class IV, one ISN class V and II and one ISN class IV and V. Six were taking an ACE-inhibitor or angiotensin receptor blocker, 6 hydroxychloroquine and 5 prednisone (mean dose 11.5 mg; range 0-30 mg). Mean mycophenolate mofetil dose at time of tacrolimus addition was 2.8 g (range 2-3 g). Mean tacrolimus dose was 3.4 mg (range 2-8 mg) titrated to a mean level of 4.67 ng/dl (range 2.2-11.8 ng/dl) for a mean of duration of 16 months (range 2-54 months). Two patients continued both therapies, while five discontinued therapy. One patient achieved a complete renal remission, while three achieved partial remission with 82.9%, 77.1%, 55.3% reductions in proteinuria. Toxicity limited the use of combination therapy: diabetic ketoacidosis (one patient), pneumonia (two) and muscle pain (two). These data suggest that adding tacrolimus in patients refractory to mycophenolate mofetil might have some benefit, although complete responses were rare. Unfortunately, tacrolimus toxicity appeared to be prevalent in these systemic lupus erythematosus patients, limiting its long term use.

The efficacy of low-dose mycophenolate mofetil for treatment of lupus nephritis in Taiwanese patients with systemic lupus erythematosus

Mycophenolate mofetil (MMF) has recently been introduced as an immunosuppressive agent for the treatment of glomerulonephritis with systemic lupus erythematosus (SLE) and the data have been encouraging. However, response to MMF treatment appears to differ ethnically. Therefore, we determined efficacy and safety of low-dose MMF for Taiwanese patients with lupus nephritis. We studied 36 lupus nephritis patients who were treated with MMF. The dose started at 0.5 g/day and we collected the data from patients who received up to 1 g/day MMF. Outcome measures were 24 h for proteinuria, serum creatinine, C3/C4 levels, and anti-dsDNA titers collected at the baseline and at 3-month treatment intervals. Daily urinary protein significantly decreased from 6.15 +/- 4.28 g to 2.69 +/- 2.36 g at the last visit (P < 0.01) in spite of the significant absence of changes in serum creatinine levels. The response rate was 65.7% including five (14.3%) cases of complete remission and 18 (51.4%) cases of partial remission. The concomitant oral prednisolone dose decreased significantly from 20.07 +/- 11.78 mg/day to 13.93 +/- 6.79 mg/day at 6 months (P < 0.01). The level of C3 increased significantly from 59.46 +/- 32.73 to 71.99 +/- 25.81 (P < 0.01) and the anti-dsDNA antibody titer decreased from 161.71 +/- 221.42 to 46.57 +/- 117.47 (P < 0.01). No severe adverse effects were observed in the study. Low-dose MMF (0.5 to 1 g/day) combined with glucocorticoids appears to be a safe and effective therapy for lupus nephritis in Taiwanese patients. Our results suggest that lupus nephritis in Oriental patients might respond to lower doses of MMF than Caucasians.

Limited sampling strategies for therapeutic drug monitoring of mycophenolate mofetil therapy in patients with autoimmune disease

Mycophenolate mofetil (MMF) is increasingly used for the treatment of autoimmune diseases (AID). In renal transplant recipients, it has been demonstrated that adjustment of the MMF dose according to the area under the plasma concentration versus time curve (AUC) of mycophenolic acid (MPA), the active moiety of MMF, improves clinical outcome. The aim of this study was to develop a maximum a posteriori Bayesian estimator (MAP-BE) to estimate MPA AUC(0-12) in patients with AID using a limited number of samples. The predictive performance of the MAP-BE was compared with a multiple linear regression method. Full MPA concentration versus time curves were available from 38 patients with AID treated with MMF. Nonlinear mixed-effect modeling was used to develop a population pharmacokinetic model. Patients were divided in an index and a validation data set. The pharmacokinetic model derived from the index data set was used to develop several MAP-BEs. The Bayesian estimators were used to predict AUC(0-12) in the validation data set on the basis of a limited number of blood samples. The bias and precision of these predictions were compared with those of limited sampling strategies developed with multiple linear regression. The absorption of MPA was described with 2 first-order processes with a short and a long lag time and a subsequent first-order elimination. The 2-compartment model accounted for the enterohepatic recirculation of MPA as well. Using 1-4 samples, MPA AUC(0-12) was adequately estimated by the MAP-BE. Bias (-5.5%) was not significantly different from zero, and precision was below 27%. The predictive performance of the multiple linear regression method was comparable. In conclusion, MAP-BEs were developed for the estimation of MPA AUC(0-12) in patients with AID. The predictive performance was good and comparable to those of the multiple linear regression method. Due to its flexibility with respect to sample times, the MAP-BE may be preferred over the multiple linear regression method.