Real-World Burden of Immunosuppressant-Treated Lupus Nephritis: A German Claims Database Analysis

INTRODUCTION

This retrospective cohort study (GSK213737) aimed to characterize treatment patterns, healthcare resource utilization (HCRU), and costs in patients with lupus nephritis (LN) initiating immunosuppressant therapy in clinical practice in Germany, to better understand the full picture of the real-world burden of LN.

METHODS

Adult patients with LN who initiated mycophenolate mofetil (MMF), intravenous cyclophosphamide (CYC), azathioprine (AZA), tacrolimus, cyclosporin A, or rituximab therapy in 2011-2017 (index therapy) were identified from the Betriebskrankenkassen German Sickness Fund database. Treatment patterns, including immunosuppressant discontinuations, and therapy switches, were assessed (maximum follow-up 4 years). Corticosteroid use, HCRU, and total economic costs were also evaluated. HCRU and costs were compared with matched controls (individuals without systemic lupus erythematosus [SLE]/LN matched by age, sex, and baseline Charlson Comorbidity Index).

RESULTS

Among 334 patients with LN, the median (interquartile range) duration of index immunosuppressant therapy use was 380.5 (126, 1064) days. Of those patients with 4 years complete enrollment, 70.8% had ≥ 1 discontinuation and 28.8% switched therapy. While most patients (71.2%) received only one immunosuppressant, gaps in treatment were common. After 1 year of follow-up, 41.6% of patients had a prednisone-equivalent corticosteroid dose of ≥ 7.5 mg/day. Patients with LN had greater HCRU use for most categories assessed and increased mean total costs per person-year versus controls (€15,115.99 versus €4,081.88 in the first year of follow-up).

CONCLUSIONS

This real-world analysis demonstrated the considerable burden of immunosuppressant-treated LN in Germany, with a high rate of discontinuations, frequent use of high-dose corticosteroids, and substantial HCRU/costs.

Lupus Nephritis in Children: Novel Perspectives

Childhood-onset systemic lupus erythematosus is an inflammatory and autoimmune condition characterized by heterogeneous multisystem involvement and a chronic course with unpredictable flares. Kidney involvement, commonly called lupus nephritis, mainly presents with immune complex-mediated glomerulonephritis and is more frequent and severe in adults. Despite a considerable improvement in long-term renal prognosis, children and adolescents with lupus nephritis still experience significant morbidity and mortality. Moreover, current literature often lacks pediatric-specific data, leading clinicians to rely exclusively on adult therapeutic approaches. This review aims to describe pediatric lupus nephritis and provide an overview of the novel perspectives on the pathogenetic mechanisms, histopathological classification, therapeutic approach, novel biomarkers, and follow-up targets in children and adolescents with lupus nephritis.

Efficacy and safety of immunosuppressive agents for adults with lupus nephritis: a systematic review and network meta-analysis

Introduction

Various immunosuppressive regimens have been developed for the treatment of lupus nephritis (LN). This study aimed to compare the efficacy and safety of immunosuppressive regimens in adults with LN.

Methods

We systematically searched the PubMed, Embase, and Cochrane Central Register of Controlled Trials databases, including conference proceedings, trial registries, and reference lists, from inception until July 10, 2022. The effects of treatment were compared and ranked using the surface under the cumulative ranking curve (SUCRA). The primary endpoint was total remission. The secondary endpoints were complete remission, systemic lupus erythematosus disease activity index (SLEDAI), relapse, all-cause mortality, end-stage renal disease (ESRD), infection, herpes zoster, ovarian failure, myelosuppression, and cancer.

Results

Sixty-two trials reported in 172 studies involving 6,936 patients were included in the network meta-analysis. The combination of tacrolimus (TAC), mycophenolate mofetil (MMF), and glucocorticoid (GC) provided the best result for the total remission rate (SUCRA, 86.63%) and SLEDAI (SUCRA, 91.00%), while the combination of voclosporin (VCS) , MMF and GC gave the best improvement in the complete remission rate (SUCRA, 90.71%). The combination of cyclophosphamide (CYC), MMF and GC was associated with the lowest risk of relapse (SUCRA, 85.57%) and cancer (SUCRA, 85.14%), while the combination of obinutuzumab (OTB), MMF and GC was associated with the lowest risk of all-cause mortality (SUCRA, 84.07%). Rituximab (RTX) plus MMF plus GC was associated with the lowest risk of ESRD (SUCRA, 83.11%), while the risk of infection was lowest in patients treated with azathioprine (AZA) plus CYC plus GC (SUCRA, 68.59%). TAC plus GC was associated with the lowest risk of herpes zoster (SUCRA, 87.67%) and ovarian failure (SUCRA, 73.60%). Cyclosporine (CsA) plus GC was associated with the lowest risk of myelosuppression (SUCRA, 79.50%), while AZA plus GC was associated with the highest risk of myelosuppression (SUCRA, 16.25%).

Discussion

This study showed that a combination of TAC, MMF and GC was the best regimen for improving the total remission rate. The optimal regimen for specific outcomes should be highlighted for high-risk patients.

Real-World Immunosuppressant Treatment Patterns for Patients with Lupus Nephritis in the United States

INTRODUCTION

Lupus nephritis (LN) treatment aims to control and prevent flares and irreversible kidney damage. Around 30% of patients are unresponsive to treatment; however, real-world LN treatment patterns have not been reported. Objectives of this retrospective cohort study (GSK 209758) were to quantify the time to switching/re-initiating induction therapy in patients with LN initiating immunosuppressant therapy and conversion from induction to maintenance immunosuppressant therapy, and to assess corticosteroid use.

METHODS

Patients with LN initiating induction or maintenance immunosuppressant therapy were identified using claims data. Patients were followed up from the index date (immunosuppressant initiation date) until treatment discontinuation, death, disenrollment, administrative censoring, or the end of follow-up period. The cumulative incidence of switching/re-initiating induction therapy and conversion to maintenance therapy was estimated using outpatient pharmacy claims and procedure codes. Corticosteroid use was estimated using pharmacy claims; a mean daily dose of ≥ 7.5 mg/day was considered high.

RESULTS

In total, 5000 patients with LN contributed 5516 treatment episodes (induction cohort, N = 372; maintenance cohort, N = 5144). In the induction cohort, the cumulative incidence (95% confidence interval) of switching between induction therapies was 24.6% (20.1-30.0) at 12 months, while 59.6% (52.4-66.1) of patients converted to maintenance therapy at 12 months. In the maintenance cohort, 21.2% (19.9-22.5) re-initiated induction therapy at 12 months. Oral corticosteroid use decreased during the follow-up in both cohorts, but 21.5% of patients remained on a high dose at 12 months in the induction cohort, while 15.8% in the maintenance cohort were taking a high dose at 24 months.

CONCLUSIONS

Around a quarter of patients with LN initiating immunosuppressant therapy switched within 12 months, while a fifth re-initiated induction therapy within 12 months. Use of high corticosteroid doses were observed during 24 months of follow-up. These data suggest that many patients do not respond to existing standard LN therapies.

KDOQI US Commentary on the 2021 KDIGO Clinical Practice Guideline for the Management of Glomerular Diseases

The KDIGO 2021 Clinical Practice Guideline for the Management of Glomerular Diseases represents the first update to this set of recommendations since the initial set of KDIGO guideline recommendations was published in 2012. The pace of growth in our molecular understanding of glomerular disease has quickened and a number of newer immunosuppressive and targeted therapies have been introduced since the original set of guideline recommendations, making such an update necessary. Despite these updates, many areas of controversy remain. In addition, further updates since the publication of KDIGO 2021 have occurred which this guideline does not encompass. With this commentary, the KDOQI work group has generated a chapter-by-chapter companion opinion article that provides commentary specific to the implementation of the KDIGO 2021 guideline in the United States.

Treatment of lupus nephritis: consensus, evidence and perspectives

Despite the continuing development of immunomodulatory agents and supportive care, the prognosis associated with lupus nephritis (LN) has not improved substantially in the past decade, with end-stage kidney disease still developing in 5-30% of patients within 10 years of LN diagnosis. Moreover, inter-ethnic variation in the tolerance of, clinical response to and level of evidence regarding various therapeutic regimens for LN has led to variation in treatment prioritization in different international recommendations. Modalities that better preserve kidney function and reduce the toxicities of concomitant glucocorticoids are unmet needs in the development of therapeutics for LN. In addition to the conventional recommended therapies for LN, there are newly approved treatments as well as investigational drugs in the pipeline, including the newer generation calcineurin inhibitors and biologic agents. In view of the heterogeneity of LN in terms of clinical presentation and prognosis, the choice of therapies depends on a number of clinical considerations. Molecular profiling, gene-signature fingerprints and urine proteomic panels might enhance the accuracy of patient stratification for treatment personalization in the future.

Long-Term Results of Triple Immunosuppression With Tacrolimus Added to Mycophenolate and Corticosteroids in the Treatment of Lupus Nephritis

Introduction

Addition of a calcineurin inhibitor (CNI) to corticosteroids and mycophenolate increased the renal response rate in lupus nephritis (LN) because of proteinuria reduction, but there is little long-term efficacy and safety data on this triple immunosuppressive regimen.

Methods

This is a cohort study of patients with class III/IV/V LN whose proteinuria persisted despite initial standard therapy with mycophenolate mofetil (MMF) and prednisolone (PRED), in whom tacrolimus (TAC) was added (target 12-hour trough TAC plasma levels of 4–6 μg/l).

Results

A total of 22 patients with LN treated with triple immunosuppression were included, with follow-up of 61.1 ± 28.1 months. Achieved trough levels of TAC and mycophenolic acid (MPA) were 3.8 to 5.7 μg/l and 1.3 to 2.1 mg/l respectively. Significant proteinuria reduction occurred after 6 months and was sustained up to 5 years. Complete response (CR) and partial response (PR) rates at 12, 24, and 36 months was 59.1%, 72.7%, and 77.3% respectively. The slope of estimated glomerular filtration rate (eGFR) over time did not change after TAC was added. A total of 7 patients (31.8%) showed progressive chronic kidney disease (CKD). Two patients reached end-stage kidney disease during follow-up. Renal survival rate at -, 3, and 5 years was 100.0%, 95.0%, and 88.7% respectively. Two patients (9.1%) had renal relapse after 8.5 ± 0.7 months. A total of 5 patients (22.7%) showed worsening of hypertension, and 3 (13.6%) had worsened hyperlipidemia. Other key adverse events included infection (n = 16, 1 in 7 patient-years) and gastrointestinal upset (n = 6).

Conclusion

Triple immunosuppression with the addition of TAC to mycophenolate and PRED resulted in further proteinuria reduction and sustained disease quiescence in patients with LN whose proteinuria did not respond optimally to standard therapy.

Systemic Lupus Erythematosus: Targeted literature review of the epidemiology, current treatment and disease burden in the Asia Pacific region

OBJECTIVE

To understand the epidemiology, current treatment and disease burden of systemic lupus erythematosus (SLE) in the Asia Pacific region (APAC).

METHODS

A targeted literature review of published evidence on SLE in APAC was conducted, using the MEDLINE® database (2008-2018), conference proceedings and other supplementary sources.

RESULTS

The review identified 70 studies conducted in China (n=15), Japan (n=13), Taiwan (n=12), Korea (n=9), Australia (n=7), Hong Kong (n=6), Singapore (n=4), and multiple places within the APAC region (n=4). Incidence rates (per 100,000 per year) ranged from 0.9-8.4, while prevalence rates ranged from 3.7-127 (per 100,000); however, recent data was limited. Asian SLE patients were reported to have higher disease severity, activity (higher SLE disease activity index scores) and organ damage accrual; along with increased morbidity, mortality, and susceptibility to renal involvement compared with other ethnicities in APAC. The risk of developing SLE is higher in the Asian population. Routinely used SLE therapies included belimumab, hydroxychloroquine, cyclophosphamide, tacrolimus, azathioprine, mycophenolate mofetil, and corticosteroids; however, prescribing patterns varied across the region. Increased disease activity was associated with high economic burden and poor quality of life for SLE patients in APAC.

CONCLUSION

SLE remains a disease with a significant unmet medical need for an innovative therapy that is well-tolerated and effective for patients in APAC. Further evidence is required to better characterize the disease and fully capture the burden and impact of SLE in APAC. This review has highlighted where there is a paucity of data from patients across the APAC region.

Outcome of biopsy-proven lupus nephritis with low glomerular filtration rate at presentation

OBJECTIVES

Currently, there is limited data regarding the outcomes of lupus nephritis (LN) with moderate to severe renal failure at presentation (defined by low glomerular filtration rate; GFR <30 mL/min).

METHODS

Sixty-four patients with biopsy-proven LN and estimated GFR (eGFR) <30 mL/min were prospectively analyzed. Outcome measure of persistently low eGFR, end-stage renal disease (ESRD) or death at 365 days were grouped as Major Adverse Kidney Events (MAKE365).

RESULTS

Diagnosis of lupus was simultaneous with onset of renal disease in 60% of cases. Histologically, 82.3% (n = 51) were class IV, the median serum creatinine was 4 mg/dL (interquartile range [IQR] 3.1-5.9 mg/dL), median eGFR was 13.75 mL/min (IQR 9.25-19 mL/min) and 42.2% (n = 27) required dialysis at presentation. Induction regimens included National Institute of Health (68.2%), Eurolupus protocol (10.9%) and mycophenolate mofetil (8%). Over 365 days, 23 (37.5%) subjects died, while 41 (62.5%) survived. The majority of deaths were due to infection and sepsis (14/23). Among the survivors, 70.7% had good renal outcome, 12.1% had persistently low GFR (<30 mL/min), while 17% developed ESRD. In this group, treatment response rate was 84.6% (complete response 25.6%, partial response 59%). Those with a better renal function at presentation had a good treatment response (100% vs. 40%). Altogether, n = 35 (54.6%) were included in the MAKE365 category. Between the renal survival group (n = 29) versus the MAKE365 group (n = 35) there was no difference in clinical or histological parameters.

CONCLUSION

The current treatment protocols had a good response rate in patients with LN even with severe kidney injury at presentation. However, the risk of serious infections and subsequent mortality was high.

Factors Associated with Renal Outcomes in an Inception Cohort of Biopsy-proven Lupus Nephritis Patients

Objective: To identify the clinical factors associated with renal response and flare in lupus nephritis (LN).

Methods: All 115 patients with biopsy-proven LN diagnosed between January 2002 and June 2015 in a tertiary centre comprised of an inception cohort that was followed up until February 2017. Baseline demographic, clinical parameters, renal biopsy histology, induction and maintenance immunosuppressive therapies, complete renal response (CRR), creatinine doubling, end-stage renal disease (ESRD), renal flares and infections were retrieved and analyzed with univariate log-rank test and multivariate Cox regression.

Results: At the time of the first renal biopsy, the age of patients was 38 ± 12.2 years (mean ± standard deviation), 90% female and systemic lupus erythematosus (SLE) disease duration 46 months (median); 67.0% were LN class IV or class IV + V. Patients were followed up for 104 ±49 months after biopsy. At months 3, 6, 12 and 24, a cumulative 25%, 46%, 66% and 76% of patients had achieved CRR, respectively. However, 49.5% who had CRR experienced [Formula: see text]1 infection of renal flare, with cumulative risk of 5%, 17%, 25% and 43% at year 1, 2, 3 and 5, respectively. Multivariate analysis showed that nephrotic syndrome ([Formula: see text] = 0.03) and delay of renal biopsy [Formula: see text]2 months from the onset of LN ([Formula: see text] ¡ 0.01) were negatively associated with CRR. Hydroxychloroquine use was beneficial in attaining CRR ([Formula: see text] = 0.03, hazard ratio = 1.70, 95% CI: 1.04, 2.80) and preventing renal flare ([Formula: see text] = 0.01, odds ratio = 0.51, 95% CI: 0.29, 0.88). By the end of the study, 80% of patients remained in CRR though 10.4% patients ended up in ESRD (all class IV), 8.7% died and 28.7% had [Formula: see text]1 infection episode requiring hospitalization.

Conclusion: Most LN patients could achieve CRR after immunosuppressive therapy but renal flares were common over time. Infective complications were fairly frequent but the incidence of ESRD was low. The use of hydroxychloroquine was associated with better renal response and fewer flares.

2019 Update of the Joint European League Against Rheumatism and European Renal Association-European Dialysis and Transplant Association (EULAR/ERA-EDTA) recommendations for the management of lupus nephritis

OBJECTIVE

To update the 2012 EULAR/ERA-EDTA recommendations for the management of lupus nephritis (LN).

METHODS

Following the EULAR standardised operating procedures, a systematic literature review was performed. Members of a multidisciplinary Task Force voted independently on their level of agreeement with the formed statements.

RESULTS

The changes include recommendations for treatment targets, use of glucocorticoids and calcineurin inhibitors (CNIs) and management of end-stage kidney disease (ESKD). The target of therapy is complete response (proteinuria <0.5-0.7 g/24 hours with (near-)normal glomerular filtration rate) by 12 months, but this can be extended in patients with baseline nephrotic-range proteinuria. Hydroxychloroquine is recommended with regular ophthalmological monitoring. In active proliferative LN, initial (induction) treatment with mycophenolate mofetil (MMF 2-3 g/day or mycophenolic acid (MPA) at equivalent dose) or low-dose intravenous cyclophosphamide (CY; 500 mg × 6 biweekly doses), both combined with glucocorticoids (pulses of intravenous methylprednisolone, then oral prednisone 0.3-0.5 mg/kg/day) is recommended. MMF/CNI (especially tacrolimus) combination and high-dose CY are alternatives, for patients with nephrotic-range proteinuria and adverse prognostic factors. Subsequent long-term maintenance treatment with MMF or azathioprine should follow, with no or low-dose (<7.5 mg/day) glucocorticoids. The choice of agent depends on the initial regimen and plans for pregnancy. In non-responding disease, switch of induction regimens or rituximab are recommended. In pure membranous LN with nephrotic-range proteinuria or proteinuria >1 g/24 hours despite renin-angiotensin-aldosterone blockade, MMF in combination with glucocorticoids is preferred. Assessment for kidney and extra-renal disease activity, and management of comorbidities is lifelong with repeat kidney biopsy in cases of incomplete response or nephritic flares. In ESKD, transplantation is the preferred kidney replacement option with immunosuppression guided by transplant protocols and/or extra-renal manifestations. Treatment of LN in children follows the same principles as adult disease.

CONCLUSIONS

We have updated the EULAR recommendations for the management of LN to facilitate homogenization of patient care.

B Cell Abnormalities in Systemic Lupus Erythematosus and Lupus Nephritis-Role in Pathogenesis and Effect of Immunosuppressive Treatments

Abnormalities in B cells play pivotal roles in the pathogenesis of systemic lupus erythematosus (SLE) and lupus nephritis (LN). Breach in central and peripheral tolerance mechanisms generates autoreactive B cells which contribute to the pathogenesis of SLE and LN. Dysregulation of B cell transcription factors, cytokines and B cell-T cell interaction can result in aberrant B cell maturation and autoantibody production. These immunological abnormalities also lead to perturbations in circulating and infiltrating B cells in SLE and LN patients. Conventional and novel immunosuppressive medications confer differential effects on B cells which have important clinical implications. While cyclophosphamide and mycophenolate mofetil (MMF) showed comparable clinical efficacy in active LN, MMF induction was associated with earlier reduction in circulating plasmablasts and plasma cells. Accumulating evidence suggests that MMF maintenance is associated with lower risk of disease relapse than azathioprine, which may be explained by its more potent and selective suppression of B cell proliferation. Novel therapeutic approaches targeting the B cell repertoire include B cell depletion with monoclonal antibodies binding to cell surface markers, inhibition of B cell cytokines, and modulation of costimulatory signals in B cell-T cell interaction. These biologics, despite showing improvements in serological parameters and proteinuria, did not achieve primary endpoints when used as add-on therapy to standard treatments in active LN patients. Other emerging treatments such as calcineurin inhibitors, mammalian target of rapamycin inhibitors and proteasome inhibitors also show distinct inhibitory effects on the B cell repertoire. Advancement in the knowledge on B cell biology has fueled the development of new therapeutic strategies in SLE and LN. Modification in background treatments, study endpoints and selective recruitment of subjects showing aberrant B cells or its signaling pathways when designing future clinical trials may better elucidate the roles of these novel therapies for SLE and LN patients.

Antiphospholipid antibodies in patients with lupus nephritis: clinical correlations and associations with long-term outcomes

Whether the presence or absence of antiphospholipid antibodies (aPL) in patients with lupus nephritis (LN) is associated with differences in clinical outcomes remains unclear. We reviewed LN patients at a single centre during 2000-2017, and compared the clinical features and long-term outcomes between patients who were seropositive or seronegative for aPL. aPL was detected in 53/149 (35.6%) patients with biopsy-proven LN, and anticardiolipin IgM, anticardiolipin IgG, anti-β2 glycoprotein I and lupus anticoagulant was detected in 18.8%, 18.1%, 10.7% and 8.1%, respectively. Follow-up was 155.8 ± 61.0 months, and was similar between aPL-seropositive and -seronegative patients. aPL seropositivity persisted in 94.3% of patients during remission. aPL-seropositive patients showed inferior patient survival (91% and 85% at 10 and 15 years, respectively, compared to 99% and 95% in aPL-seronegative patients; p = 0.043). Nine (6.0%) patients died during follow-up, including six aPL-seropositive (four thrombotic events and two bleeding complications related to anticoagulation) and three aPL-seronegative patients. aPL seropositivity was associated with more rapid decline in estimated glomerular filtration rate (-1.44 mL/min/year compared to -0.38 mL/min/year in aPL-seronegative patients; p = 0.027) and inferior long-term renal survival (82% and 74% at 10 and 15 years, respectively, compared to 91% and 87% in aPL-seronegative patients; p = 0.034). aPL-seropositive patients also had a higher incidence of thrombotic events and miscarriage (32.1% and 13.2%, respectively, compared to 16.7% and 2.1% in the aPL-seronegative group; p = 0.030 and 0.006). We concluded that aPL seropositivity was associated with inferior long-term patient and renal survival and more frequent thrombotic events and miscarriage in LN patients.

Clinical Outcomes and Clinico-pathological Correlations in Lupus Nephritis with Kidney Biopsy Showing Thrombotic Microangiopathy

Objective.

Renal thrombotic microangiopathy (TMA) is an uncommon pathological finding in lupus nephritis (LN), and its clinical significance remains to be defined.

Methods.

Twenty-four patients with lupus nephritis (LN) and renal TMA were selected from a retrospective review of 677 biopsy-proven LN patients, and compared with 48 LN controls without TMA (1:2 ratio) matched according to demographics and treatments.

Results.

Renal TMA was noted in 3.5% of kidney biopsies of LN. TMA was associated with a higher prevalence of anti-Ro (45.8% vs 18.8%; p = 0.016), higher Systemic Lupus Erythematosus Disease Activity Index scores (21.4 ± 8.5 vs 10.8 ± 2.3; p < 0.001), lower estimated glomerular filtration rate (eGFR; 16.8 ± 11.7 ml/min vs 77.8 ± 28.6 ml/min; p < 0.001), and a higher percentage of patients who required dialysis (37.5% vs 2.1%; p < 0.001) at the time of kidney biopsy. Activity and chronicity indices [median (range)] were higher in the TMA group [11 (2–19) and 3 (1–8), respectively, compared with 7 (0–15) and 1 (0–3) in controls; p = 0.004 and p < 0.001; respectively]. Patients with TMA showed inferior 5-year renal survival and higher incidence of chronic kidney disease at last followup (70% and 66.6%, respectively, compared with 95% and 29.2% in controls; p = 0.023 and 0.002, respectively). The TMA group also showed lower median eGFR compared with controls [50.1 (IQR 7–132) ml/min vs 85.0 (IQR 12–147) ml/min; p = 0.003]. Five-year patient survival rate was similar between the 2 groups (87% and 98% in TMA and control group, respectively; p = 0.127).

Conclusion.

TMA in kidney biopsy was associated with more severe clinical and histological activity, and significantly inferior longterm renal outcome in LN.

Time-dependent biases in observational studies of comparative effectiveness research in rheumatology. A methodological review

Objective

To assess to what extent time-dependent biases (ie, immortal time bias (ITB) and time-lag bias (TLB)) occur in the latest rheumatology observational studies, describe their main mechanisms and increase the awareness on this topic.

Methods

We searched PubMed for observational studies on rheumatic diseases published in leading medical journals in the last 5 years. Only studies with a time-to-event analysis exploring the association of one or more interventional strategies with an outcome were included. Each study was labelled as free from bias, at risk of TLB, at risk of misclassified ITB if the period of immortal time was incorrectly attributed to an intervention group, or at risk of excluded ITB if the immortal time was discarded from the analysis.

Results

We included 78 papers. Most studies were performed in Europe or North America (46% each), were not industry funded (62%) and had a safety primary outcome (59%). In total, 13 (17%) studies were considered at risk of time-dependent biases. Among the studies at risk of ITB (n=8; 10%), in 5 (6%), waiting time to receive treatment was wrongly attributed to the treatment exposure group, which indicated misclassified ITB. Five (6%) studies were at risk of TLB: patients on conventional synthetic disease-modifying antirheumatic drugs (DMARD; first-line drugs) were compared with patients on biologic DMARDs (second or third-line drugs) without accounting for disease duration or prior medication use.

Conclusions

One in six comparative effectiveness observational studies published in leading rheumatology journals is potentially flawed by time-dependent biases.

Lupus nephritis: An update on treatments and pathogenesis

Immunosuppressive therapies for lupus nephritis (LN) have improved significantly over the past few decades, resulting in growing number of choices for treatment individualization and improved renal and patient outcomes. Corticosteroids combined with mycophenolate or cyclophosphamide induces a satisfactory response in a high proportion of Asian and Caucasian patients, but the rate of improvement varies considerably between patients. Relatively low disease flare rate was observed in Chinese patients receiving low-dose prednisolone and mycophenolate maintenance. Short-term results with calcineurin inhibitors (CNI) are encouraging, attributed both to their immunosuppressive efficacy and the action of these agents on podocyte biology leading to more rapid proteinuria suppression. Additional data, especially on the avoidance of nephrotoxicity and metabolic side effects, is required to facilitate selection of patients appropriate for this treatment. Modifications of standard regimens such as reducing corticosteroid exposure or using enteric-coated mycophenolate might help reduce treatment-related toxicities without compromising efficacy. While clinical outcomes of patients have improved with recent therapeutic advances, individual and ethnic variations in disease manifestations and treatment response, as well as the prevention of infections and long-term complications still present challenges to frontline clinicians. Recent data from histological examination and translational studies also suggest that complement activation via the alternative pathway, immune deposition on renal tubular basement membrane, and local inflammatory responses involving resident kidney cells are of pathogenic relevance in LN. The progress of clinical and translational studies has improved not only the understanding of disease mechanisms but also clinical decision making in the management of LN.

Longterm Data on Sirolimus Treatment in Patients with Lupus Nephritis

Objective.

To expand the limited longterm data on sirolimus treatment in patients with lupus nephritis (LN). Our pilot short-term data suggested efficacy of sirolimus treatment in these patients.

Methods.

We retrospectively reviewed 16 class III/IV/V patients with LN who have received prednisolone (PSL) and sirolimus either as initial or maintenance treatment.

Results.

Sixteen patients received sirolimus treatment (9 because of intolerance to standard immunosuppressants and 7 because of a history of malignancy) for 45.3 ± 36.5 months. In 5 patients, sirolimus and PSL were given as induction for active nephritis, and they showed improvements in proteinuria (2.8 ± 1.9 g/day at baseline, 0.1 ± 0.1 g/day after 36 mos, p = 0.011), anti-dsDNA (107.7 ± 91.9 IU/ml and 37.0 ± 55.4 IU/ml, respectively, p = 0.178), and C3 (54.8 ± 26.1 mg/dl and 86.3 ± 18.6 mg/dl, respectively, p = 0.081). Eleven patients received sirolimus and low-dose PSL as longterm maintenance, and they showed continued improvement in C3 (90.4 ± 18.1 mg/dl and 117.7 ± 25.1 mg/dl at commencement and after 36 mos, respectively, p = 0.025), stable renal function (estimated glomerular filtration rate 58.6 ± 25.8 ml/min and 63.0 ± 29.6 ml/min, respectively, p = 0.239), and proteinuria (0.8 ± 0.7 g/day and 0.7 ± 0.7 g/day respectively, p = 0.252). Renal flare occurred in 1 patient, and another patient who had stage 4 chronic kidney disease when sirolimus was started developed endstage renal failure after 27 months. Sirolimus was discontinued in 5 patients, in 4 cases related to drug side effects. Deterioration of dyslipidemia occurred in 4 patients, but was adequately controlled with statin therapy.

Conclusion.

The preliminary evidence suggests that sirolimus may serve as an alternative treatment for patients with LN who do not tolerate standard treatment or who had a history of malignancy, and it has an acceptable longterm safety profile.

Pharmacokinetics and pharmacogenomics of mycophenolic acid and its clinical correlations in maintenance immunosuppression for lupus nephritis

Background

There is little data on mycophenolic acid (MPA) pharmacokinetics and pharmacogenomics and optimal MPA exposure in lupus nephritis (LN) patients during long-term maintenance.

Methods

We measured blood MPA levels at 1, 2, 4, 8, 10 and 12-h post-dose (i.e. C1, C2, C4, C8, C10 and C12) in 88 stable LN patients receiving maintenance prednisolone and mycophenolate mofetil, repeated every 6 months. The relationship between MPA exposure and single nucleotide polymorphisms (SNPs) of adenosine triphosphate–binding cassette subfamily C member 2 (ABCC2; rs2273697, rs3740066, rs717620 and rs17222723), organic anion-transporting polypeptides (OATPs; rs7311358 and rs4149117) and uridine diphosphate glucuronosyltransferase (UGT; rs17863762, rs6714486, rs17868320 and rs72551330) was also investigated.

Results

C1, C2 and C12 were 8.3 ± 6.6 , 7.2 ± 5.2 and 2.0 ± 1.4 mg/L and all correlated with the 12-h area under the curve (AUC0–12; r = 0.51, 0.85 and 0.73; P = 0.02, &lt;0.001 and &lt;0.001, respectively). C12 inversely correlated with hemoglobin, immunoglobulins and leukocyte levels (P &lt; 0.05 for all). Five renal flares, 11 episodes of infection and 10 episodes of anemia (hemoglobin &lt;10 g/dL) occurred over 96 weeks, with a corresponding C12 of 1.3 ± 0.5, 4.3 ± 2.6 and 2.9 ± 1.5 mg/L, respectively (versus 2.4 ± 1.2, 1.8 ± 1.2 and 1.7 ± 1.1 mg/L in patients without these complications; P = 0.041, &lt;0.001 and 0.004). SNP rs2273697 A/G in the ABCC2 gene was associated with lower MPA exposure compared with G/G (1075.9 ± 239.9 versus 1891.5 ± 918.9 mgh/L per g/kg; P = 0.003). SNPs of OATP and UGT were unrelated to MPA level.

Conclusion

MPA C12 correlates with the AUC0–12 and is related to renal flare, infection and anemia. SNP rs2273697 A/G is associated with lower MPA exposure.

Analysis of clinical risk factors in relapsed patients with class IV lupus nephritis

The present study aimed to investigate risk factors for renal recurrence in patients with type IV lupus nephritis (LN). Univariate and multivariate analyses were conducted to using the Cox proportional hazard model and the Kaplan-Meier method. A total 244 patients were diagnosed with type IV LN; 100 (28.49%) relapsed and 144 (41.03%) recovered successfully. Kaplan-Meier method analysis indicated that patients with type IV LN affecting the digestive tract had high renal recurrence rates. Patients with hyperglobulinemia, positive anti-ribonucleoprotein and anti-Sjögren's syndrome type B (anti-SSB) antibodies, thrombus in the loop or non-inflammatory necrotizing vasculopathy also had a high recurrence rate. Furthermore, patients achieving partial remission had an increased recurrence rate compared with patients achieving complete remission. Patients undergoing maintenance treatment with glucocorticoids alone had a higher recurrence rate compared with patients who used alternative treatment schemes. Univariate and multivariate regression analyses by the Cox proportional hazard model determined that the effect of systemic lupus erythematosus in the gastrointestinal tract, increased serum globulin levels and positive anti-SSB antibody at onset were risk factors for the recurrence of LN type IV. The present study demonstrated that clinical risk factors of renal recurrence in patients with LN type IV include LN in the gastrointestinal tract, increased serum globulin levels, positive anti-SSB antibodies at onset and the use of glucocorticoid-only maintenance treatment.

Longterm Data on Disease Flares in Patients with Proliferative Lupus Nephritis in Recent Years

Objective.

To examine the disease flare rate in lupus nephritis (LN), focusing on renal flares, and the factors associated with relapse risk in recent years.

Methods.

We analyzed data on 139 Chinese patients with class III/IV ± V LN diagnosed from January 1983 to December 2013. We also compared data before and after 1998, when maintenance immunosuppression was changed from azathioprine (AZA) to mycophenolic acid (MPA).

Results.

Over 112.5 ± 88.4 months, 135 episodes of renal flare occurred, giving a flare rate of 0.108 episodes per patient-year. The renal relapse-free survival rate was 96%, 90%, 86%, 80%, 69%, and 57% after 1, 2, 3, 4, 5, and 10 years, respectively, calculated from the start of induction treatment. Reduced risk of flare was associated with MPA maintenance (OR 0.314, 95% CI 0.099–0.994, p = 0.049), complete remission after induction immunosuppression (OR 0.329, 95% CI 0.133–0.810, p = 0.016), and diagnosis after 1998 (OR 0.305, 95% CI 0.133–0.700, p = 0.005). Relapse-free survival was significantly better in patients treated with prednisolone and MPA as maintenance immunosuppression (91% after 5 yrs and 83% after 10 yrs, respectively) compared with prednisolone and AZA (70% and 52%, respectively, p = 0.044). LN diagnosed in 1998–2013 showed 5-year and 10-year relapse-free survival rates of 93% and 86%, respectively, compared with 81% and 66%, respectively (p = 0.017) for LN that presented in 1983–1997.

Conclusion.

Our data show a relatively low flare rate for LN in the more recent era, attributed to effective induction of immunosuppression and MPA as maintenance treatment.

Flares in systemic lupus erythematosus: diagnosis, risk factors and preventive strategies

Despite advances in the treatment, patients with systemic lupus erythematosus (SLE) often experience disease exacerbations (flares) of varying severity. Their diagnosis is primarily made on clinical grounds after exclusion of other diseases or disturbances, primarily infections, and can be assisted by the use of validated clinical indices. Serological tests such as serum complement fractions and anti-dsDNA autoantibodies, are helpful in monitoring SLE activity, but they lack high diagnostic accuracy. Flares are more frequent in patients with persistent immunological and clinical activity, and have been described as significant risk factor for development of irreversible end-organ damage. Accordingly, prevention of flares has been recognized as a distinct therapeutic target in SLE and involves adequate control of disease activity, use of hydroxychloroquine, maintaining immunosuppressive or biologic therapy for several years, and avoiding non-compliance issues. The future holds promise for the discovery of biomarkers that will accurately predict or diagnose SLE flares, thus allowing for the implementation of patient-tailored preventive strategies.

Con: Cyclophosphamide for the treatment of lupus nephritis

Kidney involvement is a major determinant for morbidity and mortality in patients with systemic lupus erythematosus. The treatment target of lupus renal disease is to induce and maintain remission and to minimize disease or treatment-related comorbidities. Cyclophosphamide (CYC), in conjunction with glucocorticoids, has conventionally been used for the initial treatment of lupus nephritis. However, the major concerns of CYC are its toxicities, such as infertility, urotoxicity and oncogenicity, which are particularly relevant in women of childbearing age. As a result, maintenance therapy of lupus nephritis with an extended course of CYC pulses has largely been replaced by other immunosuppressive agents such as mycophenolate mofetil (MMF) and azathioprine. Recent randomized controlled trials have demonstrated non-inferiority of MMF to pulse CYC as induction therapy of lupus nephritis. Although MMF as induction-maintenance therapy has been increasingly used in lupus nephritis, its efficacy in the long-term preservation of renal function remains to be elucidated. MMF is not necessarily less toxic than CYC. Meta-analyses of clinical trials show similar incidence of infective complications and gastrointestinal adverse events in both MMF- and CYC-based regimens. However, considering the reduction in gonadal toxicity and the risk of oncogenicity, MMF may be used as first-line therapy of lupus nephritis. Tacrolimus (TAC) has recently been shown to be equivalent to either MMF or CYC for inducing remission of lupus nephritis and may be considered as another non-CYC alternative. Combined low-dose MMF and TAC appears to be more effective than CYC pulses in Chinese patients with lupus nephritis and has the potential to replace the more toxic CYC regimens in high-risk patients. Currently, CYC still plays an important role in the management of lupus nephritis patients with impaired or rapidly deteriorating renal function, crescentic glomerulonephritis or as salvage therapy for recalcitrant disease.

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.

Lupus Nephritis in Asia: Clinical Features and Management

BACKGROUND

Lupus nephritis (LN) is a common and severe organ involvement manifesting itself in systemic lupus erythematosus (SLE). There is a considerable difference in prevalence, severity, treatment response and outcomes between Asian LN patients and LN patients from other racial backgrounds.

SUMMARY

Asian SLE patients have a higher prevalence of LN than Caucasian SLE patients and often present with a more severe disease. Increasing data from genetic studies, accompanied by progress in high-throughput genotyping, have advanced our knowledge about genetic predispositions that might partly contribute to the clinical variations observed. Corticosteroids combined with either cyclophosphamide (CYC) or mycophenolic acid (MPA) is the current standard-of-care induction regimen for severe LN irrespective of race or ethnicity. However, the preference for MPA or CYC, and possibly the optimum dose for MPA, is influenced by the patient's origin. Also, there is an insufficient evidence base for reduced-dose intravenous CYC in Asian patients. Health economics and access to prompt diagnosis and treatment are still challenging issues in some Asian regions. The former represents a significant obstacle limiting the access of patients to MPA despite the proven efficacy of the drug as an induction agent and its superiority over azathioprine (AZA) in preventing disease flares when used for long-term maintenance immunosuppression. Calcineurin inhibitors such as tacrolimus deserve further investigation in view of their additional effect on podocytes by reducing proteinuria and the promising data from Asian patients. Despite considerable advances in the clinical management of LN over the past few decades with resultant improvements in patients' outcomes, there are still knowledge gaps and unmet clinical needs. Asia has made substantial contributions to the evidence base that guides clinical management and continues to offer invaluable opportunities for research pursuits.

KEY MESSAGES

Treatment responses and clinical outcomes in Asian patients with LN compare favorably with patients from other parts of the world. The prevention and treatment of infective complications remain significant challenges in managing LN in Asia.

FACTS FROM EAST AND WEST

(1) The prevalence of SLE is lower among Caucasians than other ethnicities. A higher prevalence is observed among Asians and African Americans, while the highest prevalence is found in Caribbean people. The prevalence of LN in Asian SLE patients is much higher than in Caucasians as well. However, the 10-year renal outcome and renal survival rate appear to be better in Asians. (2) Polymorphisms of genes involved in the immune response, such as Fcγ receptor, integrin alpha M, TNF superfamily 4, myotubularin-related protein 3 and many others, might be partly responsible for the differences in prevalence between the different ethnic groups. European ancestry was shown to be associated with a decrease in the risk of LN even after adjustment for genes most associated with renal disease. (3) Access to health care is a key determinant of disease progression, treatment outcome and the management of complications such as infections, particularly in South Asia, and might also explain disparities between clinical outcomes. (4) The efficacy of low-dose CYC combined with corticosteroids for induction treatment of LN was proved in European Caucasian patients. This treatment is also used in Asia, although no formal evaluation of efficacy and safety in comparison with other treatment regimens exists in this population. The efficacy of mycophenolate mofetil (MMF) is similar to that of CYC, and similar between Asians and Caucasians. MMF may be more effective than CYC in inducing response in high-risk populations such as African American or Hispanic patients. MMF might cause less infection-related events in Asians, but its high cost prevents broader usage at present. (5) For maintenance therapy, corticosteroid combined with AZA or MMF is used worldwide, with a broadly similar efficacy of both treatments, although there are data suggesting that in high-risk populations (e.g. African Americans) MMF may be more effective in preventing renal flares. AZA is often preferred in Asia due to economic constraints and because of its safety in pregnancy. (6) Alternative therapies under investigation include rituximab, which might be more efficient in Caucasians, as well as belimumab. Recent Japanese and Chinese studies have indicated a potential benefit of tacrolimus as a substitute for or in addition to CYC or MMF (dual or triple immunosuppression). Mizoribine is used in Japan exclusively.

Mycophenolate mofetil as maintenance therapy for childhood-onset systemic lupus erythematosus patients with severe lupus nephritis

OBJECTIVES

We evaluated histological changes occurring in renal biopsy specimens, between the time before initial induction therapy and after 12 months' maintenance therapy, as well as changes in laboratory parameters, SLE disease activity (SLEDAI), and dosage of corticosteroid (CS) in childhood-onset systemic lupus erythematosus (SLE) patients treated with mycophenolate mofetil (MMF).

METHODS

A retrospective analysis was performed on nine patients diagnosed with childhood-onset SLE and lupus nephritis. They were treated with pulsed mPSL and intravenous cyclophosphamide as induction therapy and MMF (500-1500 mg/day) plus CS as maintenance therapy. Renal biopsy was performed before the initial induction therapy and after 12 months' maintenance therapy.

RESULTS

Pathological findings at second biopsy were improved in eight of nine patients (89%). The findings of SLEDAI, urinalysis, and blood tests also showed improvement. CS doses could be tapered satisfactorily. Adverse events were observed in two patients. No patients treated with MMF experienced any disease flares during maintenance therapy.

CONCLUSIONS

MMF as maintenance therapy might be useful in that not only the histological findings of lupus nephritis were improved, but also CS doses could be beneficially tapered. Nonetheless, this is a retrospective report of only nine cases and further prospective multicenter studies are necessary.

Targeting spleen tyrosine kinase-Bruton's tyrosine kinase axis for immunologically mediated glomerulonephritis

The importance of B-cell activation and immune complex-mediated Fc-receptor activation in the pathogenesis of immunologically mediated glomerulonephritis has long been recognized. The two nonreceptor tyrosine kinases, spleen tyrosine kinase (Syk) and Bruton's tyrosine kinase (Btk), are primarily expressed by hematopoietic cells, and participate in B-cell-receptor- and Fc-receptor-mediated activation. Pharmacological inhibitors of Syk or Btk are undergoing preclinical development and clinical trials for several immune diseases; and Syk inhibitors have been shown to reduce disease activity in rheumatoid arthritis patients. However, the clinical therapeutic efficacies of these inhibitors in glomerulonephritis have not been evaluated. Herein, we review recent studies of Syk and Btk inhibitors in several experimental primary and secondary glomerulonephritis models. These inhibitors suppressed development of glomerular injury, and also ameliorated established kidney disease. Thus, targeting Syk and Btk signaling pathways is a potential therapeutic strategy for glomerulonephritis, and further evaluation is recommended.

Serum immunoglobulin G level in patients with lupus nephritis and the effect of treatment with corticosteroids and mycophenolate mofetil

BACKGROUND

Reduced serum IgG level is associated with increased risk of infection. We investigated the circulating IgG level and its determining factors in active lupus nephritis patients treated with corticosteroids and mycophenolate mofetil (MMF).

METHODS

This was a retrospective study on the longitudinal IgG profile in Class III/IV ± V lupus nephritis patients treated with prednisolone and MMF.

RESULTS

46 patients were included. At baseline, 34 (73.9%) patients (Group I) had normal or elevated IgG (1444.0 ± 600.5 mg/dL) while 12 (26.1%) (Group II) had IgG levels (567.8 ± 160.9 mg/dL) below the lower limit of normal. IgG levels at baseline, three, six and 12 months after treatment were 1215.4 ± 649.7 mg/dL, 843.9 ± 347.6 mg/dL, 914.5 ± 362.4 mg/dL and 1034.6 ± 452.5 mg/dL respectively. Treatment with prednisolone and MMF led to a significant drop in IgG after two weeks, reaching a nadir at eight weeks, followed by gradual normalization. Similar changes in IgG were observed in Group I patients but there was non-significant change in Group II within the first 24 weeks. Eighteen (39.1%) patients had low IgG by six months, and only one patient had IgG <300 mg/dL, at both three and six months. IgG level was negatively associated with proteinuria at six months (r = -0.711, p = 0.010). Five of 18 patients with low IgG had infections within the first year, while IgG levels below the lower limit of normal did not increase infection risk (relative risk 1.863; 95% confidence interval 0.466 to 6.818, p = 0.280).

CONCLUSION

Reduced IgG occurred in 26% of active lupus nephritis patients and the IgG levels are significantly influenced by the severity of proteinuria. Treatment with prednisolone and MMF does not result in clinically important suppression of IgG.

Overview of lupus nephritis management guidelines and perspective from Asia

Lupus nephritis (LN) is a common and important manifestation of systemic lupus erythematosus (SLE). Evidence suggests higher rates of lupus renal involvement in Asian populations, and maybe more severe nephritis, compared with other racial or ethnic groups. The management of LN has evolved considerably over the past three decades, based on observations from clinical studies that investigated different immunosuppressive agents including corticosteroids, cyclophosphamide, azathioprine, mycophenolic acid, calcineurin inhibitors and novel biologic therapies. This is accompanied by improvements in both the short-term treatment response rate and long-term renal function preservation. Treatment guidelines for LN have recently been issued by rheumatology and nephrology communities in U.S.A. and Europe. In view of the racial difference in disease manifestation and response to therapy, and the substantial disease burden in Asia, a panel of 15 nephrologists and rheumatologists from different Asian regions with extensive experience in lupus nephritis - the Steering Group for the Asian Lupus Nephritis Network (ALNN) - met and discussed the management of lupus nephritis in Asian patients. The group has also reviewed and deliberated on the recently published recommendations from other parts of the world. This manuscript summarizes the discussions by the group and presents consensus views on the clinical management and treatment of adult Asian patients with LN, taking into account both the available evidence and expert opinion in areas where evidence remains to be sought.

Overview of lupus nephritis management guidelines and perspective from Asia

Lupus nephritis (LN) is a common and important manifestation of systemic lupus erythematosus (SLE). Evidence suggests higher rates of lupus renal involvement in Asian populations, and maybe more severe nephritis, compared with other racial or ethnic groups. The management of LN has evolved considerably over the past three decades, based on observations from clinical studies that investigated different immunosuppressive agents including corticosteroids, cyclophosphamide, azathioprine, mycophenolic acid, calcineurin inhibitors and novel biologic therapies. This is accompanied by improvements in both the short-term treatment response rate and long-term renal function preservation. Treatment guidelines for LN have recently been issued by rheumatology and nephrology communities in U.S.A. and Europe. In view of the racial difference in disease manifestation and response to therapy, and the substantial disease burden in Asia, a panel of 15 nephrologists and rheumatologists from different Asian regions with extensive experience in lupus nephritis - the Steering Group for the Asian Lupus Nephritis Network (ALNN) - met and discussed the management of lupus nephritis in Asian patients. The group has also reviewed and deliberated on the recently published recommendations from other parts of the world. This manuscript summarizes the discussions by the group and presents consensus views on the clinical management and treatment of adult Asian patients with LN, taking into account both the available evidence and expert opinion in areas where evidence remains to be sought.

Targeting the B-cell pathway in lupus nephritis: current evidence and future perspectives

Nephritis represents a frequent, severe complication of systemic lupus erythematosus. Autoantibodies appear to be fundamental in the pathogenesis of lupus nephritis. Several hypotheses are currently experimentally tested to further elucidate the direct induction of inflammation through interaction of the pathological autoantibodies with intrinsic glomerular components and the triggering of a complement-driven autoinflammatory cascade. B-cells have, in the last decade, emerged as a promising new therapeutic target, as biological treatments successfully attempting B-cell depletion, inhibition of B-cell proliferation and differentiation, or modulation of B-cell function have become bioengineered. Clinical trials have so far proved controversial regarding the efficacy of these new agents. Thus, despite the short and long-term side effects associated with immunosuppressive treatment alternative emerging treatments are still regarded "rescue" regimens in refractory patients. In an effort to accurately evaluate the potential of these therapies in lupus nephritis, several issues have been raised mainly in terms of patient selection criteria and trial duration. This review aims to expand on the proposed pathophysiologic mechanisms implicating the B-cell pathway in the pathogenesis of lupus nephritis and summarize current knowledge obtained from clinical trials introducing these biologics in its treatment. Finally, it will elaborate on potential applications of currently available biologic agents and forthcoming treatment options.

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.