Treatment of proliferative lupus nephritis: a slowly changing landscape

Ponatinib exacerbate renal injury in systemic lupus erythematosus mouse model through PDGFR-PI3K/AKT pathway

Lupus nephritis (LN) is a common clinical complication of systemic lupus erythematosus (SLE). Proliferative lupus nephritis represents the gravest form of LN, and since effective drugs for its treatment are still lacking, tyrosine kinase inhibitors (TKIs) find extensive clinical utility due to their notable impact on suppressing cell proliferation and may serve as potential drugs for LN treatment. However, previous studies on the effects of TKI on LN have been controversial. Ponatinib, a third-generation TKI, lacks studies on its role in LN. This study aimed to investigate the impact of the ponatinib on LN. MRL/lpr mice were evaluated for renal function, autoimmune markers and histopathological changes after oral administration of ponatinib. RNA-seq analysis was performed to explore the molecular pathways involved in ponatinib-induced kidney injury. Ponatinib uniquely exacerbated renal damage in MRL/lpr mice, evidenced by a decline in renal function and acute pathological changes, without affecting lupus-related autoimmune markers. Differential expressed genes analysis and functional enrichment implicate ponatinib-induced renal damage in MRL/lpr mice associated with adiponectin. Furthermore, we verified ponatinib signaling the PI3K/AKT pathway through PDGFRα, potentially influencing high molecular weight adiponectin (HMW ADIPOQ) expression and exacerbating renal damage. In conclusion, this study demonstrates that ponatinib can up-regulate HMW ADIPOQ expression via the PI3K/AKT pathway by inhibiting PDGFRα phosphorylation, highlighting the potential nephrotoxic effects of ponatinib in lupus-prone mice, and underscoring the importance of monitoring renal function in systemic autoimmune diseases patients receiving ponatinib.

Real-World Effectiveness of Belimumab in Patients with Active Lupus

This study evaluated the real-world effectiveness of belimumab (BLM) in the treatment of systemic lupus erythematosus (SLE) patients with moderate to high disease activity. This retrospective cohort study enrolled 129 Japanese patients with moderate to high SLE disease activity who received BLM between January 2013 and March 2023. The clinical outcomes, including the flare-free survival, SLE Disease Activity Index 2000 (SLEDAI-2K) score, and prednisone-equivalent dose, in the BLM and mycophenolate mofetil (MMF) treatment groups were compared before and after treatment. Safety data for BLM were collected. Additionally, we compared the effectiveness of BLM and intravenous cyclophosphamide (IV-CY) treatment using the stabilized inverse probability of treatment weighting (IPTW) method based on the propensity scores. This observational study enrolled 129 patients with moderate/severe SLE: 48 patients received belimumab, 45 received IV-CY, and 36 received MMF and prednisolone for remission induction therapy. The median follow-up for the BLM group was 17.0 months. Among them, 19 received BLM plus MMF. BLM significantly reduced the mean SLEDAI-2K (from mean baseline to 52 weeks: 49.2% reduction from 12.8 to 6.5) and prednisone daily dose (from mean baseline to 52 weeks: 21.9% reduction from 12.8 to 10.0 mg/day). The flare-free survival at 52 weeks was not significantly different between the BLM and MMF groups. There was no significant difference in the flare-free survival rates or reduction rates of the SLEDAI-2K between the patients treated with BLM and those treated with BLM plus MMF. In the propensity score-matched comparative analyses, there was no significant difference in the flare-free survival rates or an estimated decline in the SLEDAI-2K scores between the patients with lupus treated with BLM and IV-CY. BLM may be a promising alternative treatment option for lupus patients with moderate or high disease activity who do not respond to conventional treatments.

Efficacy and safety of belimumab therapy for patients with lupus nephritis: A meta-analysis and a propensity score-matched case-control study

OBJECTIVE

In this study, we performed a meta-analysis and a propensity score-matched case-control study to evaluate the efficacy and safety of belimumab in patients with lupus nephritis (LN).

METHODS

We analyzed the data from three randomized controlled trials (RCTs) to assess the effects of belimumab treatment on renal improvement and adverse effects. Our study included a total of six LN patients who received belimumab treatment and an additional six LN patients who received standard therapy. All participants were followed up for a duration exceeding 96 weeks to evaluate the outcomes of the treatments.

RESULTS

Our meta-analysis incorporated data from three articles involving a total of 666 patients. The results of the analysis revealed that a higher proportion of patients who received belimumab treatment experienced renal improvement compared to those in the control group. The patients in belimumab group had a higher renal complete response rate and proteinuria improvement rate compared to the control group. However, belimumab treatment did not increase the renal partial response rate compared to the control group. The belimumab group also exhibited a higher proportion of patients who achieved normalization of antidouble-stranded DNA, as well as normalization of low C3 and C4 levels. In our case-control study, significant improvement in proteinuria was demonstrated with belimumab at Week 48 (p = 0.037) and at all subsequent time points (all p < 0.05). Over the course of 96 weeks, belimumab treatment was associated with renal function stabilization and an increase in C3 and C4 levels. Moreover, the use of belimumab resulted in a reduction in glucocorticoid dosage at Week 24 (p = 0.02). Additionally, patients receiving belimumab treatment had a lower risk of severe treatment-emergent adverse events, and no other significant adverse effects were observed between the two groups.

CONCLUSIONS

In patients with LN, the utilization of belimumab therapy has demonstrated notable improvements in renal response rates. Additionally, it has shown a decreased likelihood of serious treatment-related adverse events and a diminished need for glucocorticoid dosage when compared to the active control group.

The Expanding Role of Extracellular Traps in Inflammation and Autoimmunity: The New Players in Casting Dark Webs

The first description of a new form of neutrophil cell death distinct from that of apoptosis or necrosis was discovered in 2004 and coined neutrophil extracellular traps "(NETs)" or "NETosis". Different stimuli for NET formation, and pathways that drive neutrophils to commit to NETosis have been elucidated in the years that followed. Critical enzymes required for NET formation have been discovered and targeted therapeutically. NET formation is no longer restricted to neutrophils but has been discovered in other innate cells: macrophages/monocytes, mast Cells, basophils, dendritic cells, and eosinophils. Furthermore, extracellular DNA can also be extruded from both B and T cells. It has become clear that although this mechanism is thought to enhance host defense by ensnaring bacteria within large webs of DNA to increase bactericidal killing capacity, it is also injurious to innocent bystander tissue. Proteases and enzymes released from extracellular traps (ETs), injure epithelial and endothelial cells perpetuating inflammation. In the context of autoimmunity, ETs release over 70 well-known autoantigens. ETs are associated with pathology in multiple diseases: lung diseases, vasculitis, autoimmune kidney diseases, atherosclerosis, rheumatoid arthritis, cancer, and psoriasis. Defining these pathways that drive ET release will provide insight into mechanisms of pathological insult and provide potential therapeutic targets.

Association of Urine sCD163 With Proliferative Lupus Nephritis, Fibrinoid Necrosis, Cellular Crescents and Intrarenal M2 Macrophages

CD163 is a marker for alternatively activated macrophages, which have been implicated in the pathogenesis of lupus nephritis (LN). In our preliminary screening of urine proteins in LN, urine soluble CD163 (sCD163) was significantly elevated in patients with active LN. To evaluate the potential of sCD163 as a biomarker in LN, urine sCD163 was assayed in patients with active LN, active non-renal lupus patients (ANR), inactive SLE and healthy controls (HC), using ELISA and normalized to urine creatinine. The correlation of urine sCD163 with clinical parameters and renal pathological attributes was further investigated in LN patients with concurrent renal biopsies. A total of 228 SLE patients and 56 HC were included from three cohorts. Results demonstrated that urine sCD163 was significantly elevated in active LN when compared with HC, inactive SLE, or ANR in African-American, Caucasian and Asian subjects (all P < 0.001). In LN patients with concurrent renal biopsies, urine sCD163 was significantly increased in patients with proliferative LN when compared with non-proliferative LN (P < 0.001). Urine sCD163 strongly correlated with SLEDAI, rSLEDAI, activity index (AI) of renal pathology, fibrinoid necrosis, cellular crescents, and interstitial inflammation on biopsies (all P < 0.01). Macrophages, particularly M2 macrophages, the predominant cells expressing CD163 within LN kidneys, represented a potential source of elevated urine sCD163, based on single-cell RNA sequencing analysis. To conclude, urine sCD163 discriminated patients with active LN from other SLE patients and was significantly elevated in proliferative LN. It strongly correlated with concurrent AI and several specific pathological attributes, demonstrating its potential in predicting renal pathology.

The Role of NETosis in Systemic Lupus Erythematosus

Systemic lupus erythematosus is an autoimmune disease affecting multiple organs with devastating pathological consequences. Current treatment regimens largely rely on immunosuppressants and corticosteroids to attenuate autoimmune activity. However, such treatments have toxic side effects, often lacks efficacy, and inherently leaves the patient prone to infections, making the discovery of novel biomarkers and therapeutic targets an urgent need. Neutrophil extracellular traps (NETs) that participate in host defense are generated by neutrophils by a process called NETosis. NETs play an important role in the pathogenesis of SLE. In this review, we discuss the current literature regarding the role of NETs in SLE while entertaining the possibility that NETosis could serve as therapeutic targets thereby rendering the treatment more specific and effective in comparison to the current lupus therapy.

ANCA positivity at the time of renal biopsy is associated with chronicity index of lupus nephritis

We investigated the association of antineutrophil cytoplasmic antibody (ANCA) positivity with lupus nephritis (LN) activity, histological features and prognosis in Korean patients with biopsy-proven LN having the results of both myeloperoxidase (MPO-ANCA) and proteinase 3 (PR3)-ANCA. We retrospectively reviewed the medical records of 91 LN patients having the results of ANCA. We divided patients with LN into the two groups according to the ANCA positivity. We collected clinical and laboratory data at kidney biopsy and histological features such as LN class including class I, II, III, IV-S, IV-G and V, and activity and chronicity index. We evaluated prognosis of LN during the follow-up by death and kidney failure. Twelve of 91 patients (13.2%) had ANCA at kidney biopsy. There were no differences in demographic data, comorbidities, reasons for kidney biopsy and laboratory data at kidney biopsy between patients with and without ANCA. In 12 LN patients with ANCA, Class III was the most frequently observed LN class (41.7%), while in 79 LN patients without ANCA, class IV-G was the most often detected LN class (35.4%). There were no meaningful differences in classes of LN between the two groups. On the other hand, patients with ANCA exhibited the higher median chronicity index than those without (2.5 vs. 1.0, P = 0.028), unlike activity index. ANCA positivity exhibited no association with death or kidney failure during the follow-up. ANCA positivity at kidney biopsy is associated with chronicity index of LN.

Polyomavirus BK, BKV microRNA, and urinary neutrophil gelatinase-associated lipocalin can be used as potential biomarkers of lupus nephritis

Objective

Lupus nephritis (LN) frequently progresses to end-stage renal disease. Finding a biomarker for LN and a predictor for the development of chronic kidney disease (CKD) is important for patients with systemic lupus erythematosus (SLE).

Methods

Ninety patients with SLE were divided into biopsy-proven LN (n = 54) and no kidney involvement (non-LN) (n = 36) groups and followed up for 54 months.

Results

Of 36 patients with LN, 3 (5.6%) had class II disease, 3 (5.6%) had class III, 35 (64.8%) had class IV, 10 (18.5%) had class V, and 3 (5.6%) had class VI (advanced sclerosis). Compared to the non-LN group, patients in the LN group had higher autoimmunity evidenced by a higher proportion of low C3 and C4 levels, positive anti-double-stranded DNA antibody levels, and lower estimated glomerular filtration rates (eGFR). Urinary neutrophil gelatinase-associated lipocalin (uNGAL) levels were significantly higher in the LN group (LN vs non-LN, 670 vs 33 ng/mL, respectively). The patients with LN had a higher urinary polyomavirus BK (BKV) load (3.6 vs 3.0 log copies/mL) and a lower urinary BKV miRNA (miR-B1) 5p level (0.29 vs 0.55 log copies/mL, p = 0.025), while there was no significant difference in the level of miR-B1-3p. Urinary miR-B1-5p level but not urinary BKV load was negatively correlated with uNGAL level (r = -0.22, p = 0.004). At the cutoff value of 80 ng/mL, the receiver operating characteristic curve analysis showed that uNGAL level as a predictor of the presence of LN had a high sensitivity (98%) and specificity (100%) (area under the curve [AUC], 0.997; p < 0.001). During the 54-month follow-up period, 14 (7%) patients with LN and none of the non-LN patients developed CKD. Multivariate Cox regression analysis revealed that baseline uNGAL level was the only predictive factor for CKD development, while baseline serum creatinine level and eGFR were not.

Conclusion

An elevated urinary BKV viral load with a decreased level of miR-B1 implies the presence of LN. In addition, an increased uNGAL level is a good biomarker not only in predicting the presence of LN but also for prediction of CKD development in patients with SLE.

Intranuclear delivery of the transcription modulation domain of Tbet-improved lupus nephritis in (NZB/NZW) F1 lupus-prone mice

Excessive expression of Tbet and IFNγ is evidence of systemic lupus erythematosus (SLE) in lupus patients. In this study, the nucleus-transducible form of Transcription Modulation Domain (TMD) of Tbet (ntTbet-TMD), which is a fusion protein between Protein Transduction Domain Hph-1 (Hph-1-PTD) and the TMD of Tbet comprising DNA binding domain and isotype-specific domain, was generated to inhibit Tbet-mediated transcription in the interactomic manner. ntTbet-TMD was effectively delivered into the nucleus of the cells and specifically inhibited Tbet-mediated transcription without influencing the differentiation of other T cell subsets and signaling events for T cell activation. The severity of nephritis was significantly reduced by ntTbet-TMD as effectively as methylprednisolone in lupus-prone mice. The number of Th1, Th2 or Th17 cells and the secretion of their cytokines substantially decreased in the spleen and kidney of lupus-prone mice by ntTbet-TMD treatment. In contrast to methylprednisolone, the marked increase of Treg cells and the secretion of their immunosuppressive cytokine were detected in the spleen of (NZB/NZW) F1 mice treated with ntTbet-TMD. Thus, ntTbet-TMD can improve nephritis in lupus-prone mice by modulating the overall proinflammatory microenvironment and rebalancing T cell subsets, leading to new immune therapeutics for Th1-mediated autoimmune diseases.

Renal outcome after kidney-transplantation in Korean patients with lupus nephritis

We investigated renal outcome of kidney-transplantation in 19 Korean recipients with biopsy-proven lupus nephritis and compared it with 18 Korean age- and gender-matched recipients without lupus nephritis who were diagnosed with end-stage renal disease caused by renal diseases other than lupus nephritis in a single centre. We reviewed histological findings of kidneys and calculated cumulative dose of immunosuppressive agents. We assessed renal flare of systemic lupus erythematosus, recurrence of lupus nephritis and graft failure as prognosis. The mean age of recipients with lupus nephritis was 43.5 years and all patients were female. Six patients had class III, 10 had class IV and three had class V. There were no meaningful differences in demographic data, renal replacement modality, cumulative doses of immunosuppressants and prognosis between recipients with and without lupus nephritis. Eight patients experienced renal flare of systemic lupus erythematosus, but there were no cases of recurrence of lupus nephritis or graft failure in recipients with lupus nephritis. Kidney-recipients with class IV lupus nephritis exhibited a lower cumulative renal flare of systemic lupus erythematosus free survival rate than those with class III lupus nephritis. In conclusion, renal outcome of kidney-transplantation in patients with lupus nephritis is similar to that in those without lupus nephritis, and class IV was associated with renal flare of systemic lupus erythematosus.

Comparison of renal response to four different induction therapies in Japanese patients with lupus nephritis class III or IV: A single-centre retrospective study

The recent recommendations for the management of lupus nephritis suggest that racial background should be considered while choosing induction therapy. However, the responses to different induction regimens have been poorly studied in Japanese population. Here, we assessed the renal response to different induction therapies in Japanese patients with lupus nephritis class III or IV. The records of 64 patients with biopsy-proven lupus nephritis class III or IV were retrospectively evaluated according to therapy received: monthly intravenous cyclophosphamide (IVCY), the Euro-lupus nephritis trial (ELNT) protocol-IVCY, tacrolimus (TAC), or mycophenolate mofetil (MMF). We investigated cumulative complete renal response (CR) rates and relapse rates for each group for 3 years. Organ damage was assessed with the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI). There were 22 patients on monthly IVCY, 18 on ELNT-IVCY, 13 on TAC, and 11 on MMF. Lower systemic lupus erythematosus disease activity index (SLEDAI) and higher CH50 were found in the TAC group at baseline (p<0.01 and p<0.01, respectively). There were no significant differences of cumulative CR rates and relapse free survival for 3 years among the four different therapeutic regimens (p = 0.2 and p = 0.2, respectively). There was a tendency to have early response and early relapse in TAC group and late response in MMF group. The SDI increase over 3 years was found more frequently in the TAC group than in the monthly-IVCY group (p = 0.04). Multivariate analysis indicated that CR at 3 months was independent prognosticator for low damage accrual. Regarding lower damage accrual, early CR achievement might be essential in induction therapy regardless of immunosuppressant choice.

Lupus Nephritis: A Different Disease in European Patients?

BACKGROUND

Lupus nephritis (LN) is still associated with significant mortality and substantial risk of progression to end-stage renal failure. Its outcome is related to the class and severity of LN and response to treatment, and it is poorer in patients with renal relapses. Ethnicity has a relatively well-defined impact on the outcome of the patients and their response to treatment and must always be taken into consideration in treatment decisions.

SUMMARY

In this article, we provide a review of the impact of ethnicity on the prevalence of systemic lupus erythematosus (SLE), the proportion of patients with SLE developing LN, outcomes of SLE and LN and response of LN to treatment. In European patients, the prevalence of SLE and the proportion of SLE patients with LN are lower and the outcome of LN is better than in nonwhite populations. European patients may respond better to some modes of treatment [e.g. cyclophosphamide (CYC) or rituximab] and may be less frequently refractory to treatment compared to black patients with LN. Although these differences may be largely genetically driven, socioeconomic factors (poverty, education, insurance, access to health care and adherence to treatment) may also play a significant role in some disadvantaged patients.

KEY MESSAGE

Treatment of LN may be different in patients with different ethnicity. Less aggressive disease in European patients may better respond to less aggressive treatment. Treatment of LN in nonwhite patients may require newer (more effective) therapeutic approaches, but targeting negative socioeconomic factors might be even more effective.

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 azathioprine (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.

Limitations of standard immunosuppressive treatment in ANCA-associated vasculitis and lupus nephritis

Introduction of the standard immunosuppressive treatment has dramatically changed the outcome of patients with both ANCA-associated vasculitis and lupus nephritis, transforming them from incurable diseases with very high short-term mortality to chronic debilitating diseases with much lower short-term, but still relatively high long-term, morbidity/mortality. Long-term morbidity with damage accumulating partly due to the adverse events of the available treatment (namely gonadal toxicity, malignancy, bone disease, cataracts, diabetes, and thromboembolic and cardiovascular disease) has become a major concern. Although cyclophosphamide-based regimens have been partly replaced by newer agents in both ANCA-associated vasculitis and lupus nephritis (namely rituximab or mycophenolate, respectively) their short-term and medium-term adverse events may not be significantly less frequent and we can only hope that new treatments will translate into better long-term outcomes including better long-term safety.

Lupus nephritis: review of the literature

Physicians in practice should be knowledgeable regarding several aspects of autoimmune disorders, especially systemic lupus erythematosus (SLE) and lupus nephritis. These disorders can present to the clinician's clinic and private office regardless of their specialty. This review will discuss various aspects of SLE, its mechanisms of disease, role of accelerated atherosclerosis, proinflammatory cytokines, and therapeutic approaches. The role of vascular endothelial growth factor in which and plasma levels have been associated with disease activity, classification of severity, and diagnosis of lupus nephritis is addressed. Current treatment options, prognosis, and future therapeutic approaches and common side effects are also discussed.

Mycophenolate mofetil versus azathioprine as maintenance therapy for lupus nephritis: a meta-analysis

AIM

The options for long-term maintenance therapy in lupus nephritis (LN) remain controversial. This meta-analysis of randomized controlled trials (RCTs) assessed the prognosis and safety of mycophenolate mofetil (MMF) versus azathioprine (AZA) used as maintenance therapy for lupus nephritis.

METHODS

The data of Cochrane Library, PubMed, EMBASE were retrieved to search the studies about the RCT studies that compared MMF with AZA used as maintenance therapy for lupus nephritis. We extracted the data reflecting prognosis, which included mortality, end-stage renal failure (ESRF), renal relapse, doubling serum creatinine, and adverse effects, then further analyzed the combined results of data and calculated the relative risk (RR).

RESULTS

Four RCT studies including 328 patients were enrolled into our meta-analysis. There was no difference between the patients receiving either MMF or AZA for maintenance therapy in preventing relapse, progression to end-stage renal failure, death and doubling of serum creatinine. MMF is not superior to AZA in terms of the risks of infection and gastrointestinal upset, but fewer patients receiving MMF developed leukopenia (RR 0.12; 95% confidence interval (CI), 0.04-0.39; P = 0.0004) and amenorrhoea (RR 0.17; 95% CI, 0.04-0.72; P = 0.02) than those receiving AZA.

CONCLUSION

The current limited evidence suggests that MMF offers similar prognosis as AZA for maintenance therapy, while MMF appears safer than AZA in the treatment of lupus nephritis.

Predictors of renal relapse in Korean patients with lupus nephritis who achieved remission six months following induction therapy

Renal relapse in patients with lupus nephritis (LN) is a risk factor for poor renal function. Therefore, there is a need to identify clinical and serological risk factors for renal relapse. A total of 108 patients with LN were enrolled in this study. All the subjects had achieved complete remission or partial remission following six months of induction therapy. We retrospectively analyzed their clinical and laboratory indices, final renal function, and kidney biopsy findings. The median follow-up period after LN diagnosis was 81 months. Renal relapse had occurred in 36 patients; it occurred in 38% and 46% of patients within five and 10 years after achievement of renal remission, respectively. There was no difference between the relapsed rate in patients with complete remission and that in those with partial remission. Clinical variables at LN onset and renal biopsy findings in the patients with sustained remission and relapsed patients were also not different. The probability of renal relapse was significantly higher in patients with an earlier age of onset of systemic lupus erythematosus (SLE) (≤ 28 years versus >28 years; HR 7.308, P = 0.001), seronegativity for anti-Ro antibody (seronegativity versus seropositivity; HR 3.514, P = 0.007), and seropositivity for anti-dsDNA antibody at six months after initiation of induction therapy (HR 8.269, P = 0.001). Our study demonstrated that early onset of SLE, seronegativity for anti-Ro antibody and increased anti-dsDNA antibody following six months of induction therapy independently predict renal relapse among the LN patients.

B-cell depletion in the treatment of lupus nephritis

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease that is clinically heterogeneous and affects multiple organs. Lupus nephritis is the most frequent severe manifestation of SLE. Conventional immunosuppressive therapy has increased the life expectancy of patients diagnosed with lupus nephritis, but only 70-80% of patients respond to this treatment and its adverse effects are considerable. B cells are central to the pathogenesis of SLE and are, therefore, an attractive therapeutic target. B-cell depletion has been used successfully to treat other autoimmune diseases, such as rheumatoid arthritis and antineutrophil cytoplasmic antibody-associated vasculitis, and many case reports and small nonrandomized trials of B-cell-depleting agents in patients with lupus nephritis have reported positive results. By contrast, two large placebo-controlled trials designed to investigate the efficacy of the B-cell-depleting agents rituximab and ocrelizumab as a treatment for lupus nephritis, failed to meet their primary efficacy end points (LUNAR and BELONG, respectively). This Review discusses the current evidence on the use of B-cell depletion in the treatment of lupus nephritis, which is derived from case studies and clinical trials including a total of over 800 patients.

Mycophenolate mofetil versus intravenous cyclophosphamide for induction treatment of proliferative lupus nephritis in a Japanese population: a retrospective study

OBJECTIVES

Recent studies have shown that mycophenolate mofetil (MMF) is similar to intravenous cyclophosphamide (IVC) for the treatment of lupus nephritis (LN), but that treatment response may vary according to location and race/ethnicity. Moreover, no studies have been conducted to compare the efficacy of MMF with that of IVC for a Japanese population. We therefore conducted a retrospective study to clarify the efficacy and safety of MMF compared with that of IVC for induction therapy for active LN, classes III and IV, in a Japanese population of 21 patients, 11 of whom received MMF and 10 IVC.

METHODS

The primary endpoint was expressed as the percentage of responders, who in turn were defined as the patients who met complete or partial response criteria according to the European consensus statement. The secondary endpoints comprised the renal activity component and serological activity.

RESULTS

The primary endpoint was achieved in nine (81.8 %) patients receiving MMF and in four (40.0 %) receiving IVC, with no significant difference between the two groups (p = 0.081), while there was also no significant difference between them in terms of secondary endpoints. However, the MMF group suffered significantly fewer hematologic toxic effects than the IVC group.

CONCLUSIONS

MMF may be used as an alternative to IVC for inducing renal remission of LN in Japanese patients.