Is newer safer? Adverse events associated with first-line therapies for ANCA-associated vasculitis and lupus nephritis

Early infectious risk in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis according to remission-induction therapy

OBJECTIVE

Few comparative data exist on early infections secondary to remission-induction therapy (RIT) with rituximab (RTX) versus cyclophosphamide (CYC) in newly diagnosed anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) patients. We compared and analysed the rates and predictors of severe infection in such patients within the first 6 months following RIT.

METHOD

From the Caen University Hospital databases, we included all consecutive adults newly diagnosed with ANCA-positive granulomatosis with polyangiitis or microscopic polyangiitis between January 2006 and December 2019. We compared rates of survival without severe infection and survival without infections of any severity within 6 months of RIT and used a multivariate Cox analysis to identify predictors of infection.

RESULTS

We included 145 patients, 27 in the RTX and 118 in the CYC group. Patients in the RTX group more frequently had pneumococcal vaccination (p < 0.01) and creatinine < 150 µmol/L; other characteristics were comparable between the two groups. Overall, 37 severe infections and 65 infections of any severity were recorded. Rates of survival without severe infection were similar in both groups (p = 0.69), but survival without infections of any severity was lower in the RTX group (p = 0.005). In multivariate analysis, risk factors at diagnosis for severe infections included chronic urinary tract disease, dialysis, and absence of trimethoprim-sulfamethoxazole prophylaxis (p < 0.01 each).

CONCLUSIONS

Within 6 months of RIT, rates of survival without severe infection were similar in newly diagnosed ANCA-positive AAV patients treated with RTX or CYC, but survival rates without infections of any severity appeared to be lower with RTX treatment.

Factors associated with cytomegalovirus infection in antineutrophil cytoplasmic antibody-associated vasculitis: A narrative review

Patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV) are vulnerable to opportunistic infections, including cytomegalovirus (CMV) infection. This narrative review aims to identify factors associated with CMV infection in patients with AAV. The literature review was conducted on Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane, PubMed, Scopus, and Web of Science. The start date of the literature search was unrestricted and the end date was February 2022. CMV infection was defined as (a) CMV pp65 antigenemia or positive CMV DNA viral load by polymerase chain reaction or CMV detection on histological specimens, with associated signs and symptoms compatible with CMV infection; (b) presence of CMV clinical syndrome (defined as presence of compatible symptoms and signs and documentation of CMV by biopsy by virus isolation, rapid culture, immunohistochemistry, or DNA in biopsy material as defined by the CMV Drug Development Forum); and (c) CMV infection as coded by the International Statistical Classification of Diseases and Related Health Problems, 10th revision with at least one prescription for CMV treatment. We identified 4505 articles, of which three (2327 patients with AAV) were included. All studies were retrospective and only one of the three studies included only patients with AAV. Low or decreasing lymphocyte counts and higher prednisolone usage were associated with CMV infection in patients with AAV. Patients with AAV with lymphopenia and on high doses of prednisolone should be monitored closely for signs and symptoms of CMV infection, and might benefit from CMV prophylaxis. Prospective studies are urgently needed to better identify causes of CMV infections in patients with AAV.

The neutrophil-to-lymphocyte ratio as a marker of vasculitis activity, severe infection and mortality in anca-associated vasculitis: A retrospective study

INTRODUCTION

Anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) is a multisystemic disease. Despite the improvement in mortality rate since the introduction of immunosuppression, long-term prognosis is still uncertain not only because of the disease activity but also due to treatment associated adverse effects. The neutrophil-to-lymphocyte ratio (NLR) has been demonstrated as an inflammatory marker in multiple settings. In this study, we aimed to investigate the prognostic ability of the NLR in AAV patients.

METHODS

We conducted a retrospective analysis of the clinical records of all adult patients with AVV admitted to the Nephrology and Renal Transplantation Department of Centro Hospitalar Universitário Lisboa Norte from January 2006 to December 2019. NLR was calculated at admission. The outcomes measured were severe infection at 3 months and one-year mortality. The prognostic ability of the NLR was determined using the receiver operating characteristic (ROC) curve. A cut-off value was defined as that with the highest validity. All variables underwent univariate analysis to determine statistically significant factors that may have outcomes. Only variables which significantly differed were used in the multivariate analysis using the logistic regression method.

RESULTS

We registered 45 cases of AVV. The mean age at diagnosis was 67.5±12.1 years and 23 patients were male. The mean Birmingham Vasculitis Activity Score (BVAS) at presentation was 26.0±10.4. Twenty-nine patients were ANCA-MPO positive, 7 ANCA-PR3 positive and 9 were considered negative ANCA vasculitis. At admission, mean serum creatinine (SCr) was 4.9±2.5mg/dL, erythrocyte sedimentation rate (ESR) was 76.9±33.8mm/h, hemoglobin was 9.5±1.7g/dL, C-reactive protein was 13.2±5.8mg/dL and NLR was 8.5±6.8. Thirty-five patients were treated with cyclophosphamide, eight patients with rituximab for induction therapy. Twenty patients developed severe infection within the first three months after starting induction immunosuppression. In a multivariate analysis, older age (73.6±10.5 vs. 62.6±11.3, p=0.002, adjusted OR 1.08 [95% CI 1.01-1.16], p=0.035) and higher NLR (11.9±7.4 vs. 5.9±5.0, p=0.002, adjusted OR 1.14 [95% CI 1.01-1.29], p=0.035) were predictors of severe infection at 3 months. NLR ≥4.04 predicted severe infection at 3 months with a sensitivity of 95% and specificity of 52% and the AUROC curve was 0.0794 (95% CI 0.647-0.900). Nine patients died within the first year. Severe infection at 3 months was independently associated with mortality within the first year (OR 6.19 [95% CI 1.12-34.32], p=0.037).

CONCLUSIONS

NLR at diagnosis was an independent predictor of severe infection within the first 3 months after immunosuppression start, and severe infection within the first three months was consequently correlated with one-year mortality. NLR is an easily calculated and low-cost laboratory inflammation biomarker and can prove useful in identifying AAV patients at risk of infection and poorer prognosis.

Association between body mass index and severe infection in older adults with microscopic polyangiitis: a retrospective cohort in Japan

BACKGROUND

Although previous studies have evaluated risk factors for the incidence of severe infection in patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV), the relationship between body mass index (BMI) and severe infection in AAV has not been elucidated. We hypothesized that older adults with AAV and a low BMI would be at a higher risk of infection. We therefore investigated the association between underweight status at AAV diagnosis and subsequent occurrence of severe infection in older adults with AAV.

METHODS

This single-center retrospective cohort study included 93 consecutive older adults with microscopic polyangiitis (MPA) treated at the Aichi Medical University Hospital in Japan between 2004 and 2018. The relationships between BMI at diagnosis and subsequent first severe infection were assessed using multivariate Cox proportional hazards models. The cumulative probability of the development of the first severe infection was calculated using the Kaplan-Meier method and the log-rank test. The level of statistical significance was set at P <  0.05.

RESULTS

During the median follow-up period of 19 (6-53) months, 29 (31.2%) patients developed at least one severe infection. Older age (adjusted hazard ratio [HR] = 2.02, 95% confidence interval [CI]: 1.14-3.52, per 10 years; P =  0.016), low BMI (< 18.5 kg/m² compared with normal BMI [18.5-23.0 kg/m²], adjusted HR =  2.63, 95% CI: 1.11-6.19; P =  0.027), and use of methylprednisolone pulse therapy (adjusted HR = 2.48, 95% CI: 1.07-5.76; P =  0.034) were found to be significant predictors of severe infection.

CONCLUSIONS

Low BMI was associated with a higher risk of severe infection in older adults with MPA, suggesting that careful management may be required to prevent this complication in this vulnerable group. Further studies are needed to elucidate the optimal treatment strategy for these patients.

Predictive factors of severe infections in patients with systemic necrotizing vasculitides: data from 733 patients enrolled in five randomized controlled trials of the French Vasculitis Study Group

OBJECTIVES

Infections remain a major cause of morbidity and mortality in systemic necrotizing vasculitides (SNV). We aimed to identify factors predicting severe infections (SI) in SNV.

METHODS

Data from five randomized controlled trials (RCTs) enrolling 733 patients were pooled. The primary end point was the occurrence of SI, defined by the need of a hospitalization and/or intravenous anti-infectious treatment and/or leading to death.

RESULTS

After a median follow-up of 5.2 (interquartile range 3-9.7) years, 148 (20.2%) patients experienced 189 SI, and 98 (66.2%) presented their first SI within the first 2 years. Median interval from inclusion to SI was 14.9 (4.3-51.7) months. Age ≥65 years (hazard ratio (HR) 1.49 [1.07-2.07]; P=0.019), pulmonary involvement (HR 1.82 [1.26-2.62]; P=0.001) and Five Factor Score ≥1 (HR 1.21 [1.03-1.43]; P=0.019) were independent predictive factors of SI. Regarding induction therapy, the occurrence of SI was associated with the combination of GCs and CYC (HR 1.51 [1.03-2.22]; P = 0.036), while patients receiving only GCs were less likely to present SI (HR 0.69 [0.44-1.07]; P = 0.096). Finally, occurrence of SI had a significant negative impact on survival (P<0.001).

CONCLUSION

SI in SNV are frequent and impact mortality. Age, pulmonary involvement and Five Factor Score are baseline independent predictors of SI. No therapeutic regimen was significantly associated with SI but patients receiving glucocorticoids and CYC as induction tended to have more SI.

The neutrophil-to-lymphocyte ratio as a marker of vasculitis activity, severe infection and mortality in anca-associated vasculitis: A retrospective study

INTRODUCTION

Anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) is a multisystemic disease. Despite the improvement in mortality rate since the introduction of immunosuppression, long-term prognosis is still uncertain not only because of the disease activity but also due to treatment associated adverse effects. The neutrophil-to-lymphocyte ratio (NLR) has been demonstrated as an inflammatory marker in multiple settings. In this study, we aimed to investigate the prognostic ability of the NLR in AAV patients.

METHODS

We conducted a retrospective analysis of the clinical records of all adult patients with AVV admitted to the Nephrology and Renal Transplantation Department of Centro Hospitalar Universitário Lisboa Norte from January 2006 to December 2019. NLR was calculated at admission. The outcomes measured were severe infection at 3 months and one-year mortality. The prognostic ability of the NLR was determined using the receiver operating characteristic (ROC) curve. A cut-off value was defined as that with the highest validity. All variables underwent univariate analysis to determine statistically significant factors that may have outcomes. Only variables which significantly differed were used in the multivariate analysis using the logistic regression method.

RESULTS

We registered 45 cases of AVV. The mean age at diagnosis was 67.5±12.1 years and 23 patients were male. The mean Birmingham Vasculitis Activity Score (BVAS) at presentation was 26.0±10.4. Twenty-nine patients were ANCA-MPO positive, 7 ANCA-PR3 positive and 9 were considered negative ANCA vasculitis. At admission, mean serum creatinine (SCr) was 4.9±2.5mg/dL, erythrocyte sedimentation rate (ESR) was 76.9±33.8mm/h, hemoglobin was 9.5±1.7g/dL, C-reactive protein was 13.2±5.8mg/dL and NLR was 8.5±6.8. Thirty-five patients were treated with cyclophosphamide, eight patients with rituximab for induction therapy. Twenty patients developed severe infection within the first three months after starting induction immunosuppression. In a multivariate analysis, older age (73.6±10.5 vs. 62.6±11.3, p=0.002, adjusted OR 1.08 [95% CI 1.01-1.16], p=0.035) and higher NLR (11.9±7.4 vs. 5.9±5.0, p=0.002, adjusted OR 1.14 [95% CI 1.01-1.29], p=0.035) were predictors of severe infection at 3 months. NLR ≥4.04 predicted severe infection at 3 months with a sensitivity of 95% and specificity of 52% and the AUROC curve was 0.0794 (95% CI 0.647-0.900). Nine patients died within the first year. Severe infection at 3 months was independently associated with mortality within the first year (OR 6.19 [95% CI 1.12-34.32], p=0.037).

CONCLUSIONS

NLR at diagnosis was an independent predictor of severe infection within the first 3 months after immunosuppression start, and severe infection within the first three months was consequently correlated with one-year mortality. NLR is an easily calculated and low-cost laboratory inflammation biomarker and can prove useful in identifying AAV patients at risk of infection and poorer prognosis.

Rituximab in adult minimal change disease and focal segmental glomerulosclerosis - What is known and what is still unknown?

Primary forms of minimal change disease and focal segmental glomerulosclerosis are rare podocytopathies and clinically characterized by nephrotic syndrome. Glucocorticoids are the cornerstone of the initial immunosuppressive treatment in these two entities. Especially among adults with minimal change disease or focal segmental glomerulosclerosis, relapses, steroid dependence or resistance are common and necessitate re-initiation of steroids and other immunosuppressants. Effective steroid-sparing therapies and introduction of less toxic immunosuppressive agents are urgently needed to reduce undesirable side effects, in particular for patients whose disease course is complex. Rituximab, a B cell depleting monoclonal antibody, is increasingly used off-label in these circumstances, despite a low level of evidence for adult patients. Hence, critical questions concerning drug-safety, long-term efficacy and the optimal regimen for rituximab-treatment remain unanswered. Evidence in the form of large, multicenter studies and randomized controlled trials are urgently needed to overcome these limitations.

Renal biopsy in very elderly patients (over 80 years): clinical presentation, histological diagnosis, and long-term outcome

PURPOSE

Data regarding the long-term outcome of very elderly (VE) patients undergoing renal biopsy (RB) are lacking. The objective of this study was to analyse the outcome of VE patients undergoing RB.

METHODS

All patients over 65 years that underwent native RB between 2004 and 2016 in our center were included. Among the 206 included patients, those over 80 years (VE, 46 patients) were analysed and compared to those aged 65-80 years (160 patients). The outcomes of the VE group were analysed.

RESULTS

Baseline characteristics, renal presentation, safety of RB and RB-related diagnosis were not different between VE patients and 65-80-year-old patients. Survival of VE patients was 73.1, 50.6 and 21.8% at 2, 4 and 6 years after RB, significantly poorer than those of 65-80-year-old group. Early death (< 1 year) occurred in 10 VE patients, was associated with a higher proteinuria-to-creatininuria ratio and tended to be associated with a more frequent dialysis need at RB. Of the 46 VE patients, 31 (67.4%) were diagnosed with a potentially reversible kidney disease, of whom 17 (40%) were started on immunosuppressive regimens. Survival of patients with a reversible kidney disease tended to be better than those with other diseases.

CONCLUSION

RB appears as a safe and valuable procedure to assess diagnosis of kidney disease in VE patients. Our data suggest that RB is critical for the identification and treatment decision of patients with potentially reversible diseases and may translate in clinical improvement.

Rituximab use in adult glomerulopathies and its rationale

Glomerulopathies are one of the leading causes of end-stage renal disease. In the last years, clinical research has made significant contributions to the understanding of such conditions. Recently, rituximab (RTX) has appeared as a reasonably safe treatment. The Kidney Disease: Improving Global Outcomes guidelines (KDIGO) recommended RTX only as initial treatment in antineutrophil cytoplasm antibody associated vasculitis (AAV) and in non-responders patients with lupus nephritis (LN), but these guidelines have not been updated since 2012. Nowadays, RTX seems to be at least as effective as other immunosuppressive regimens in idiopathic membranous nephropathy (IMN). In minimal-change disease, (MCD) this drug might allow a long-lasting remission period in steroid-dependent or frequently relapsing patients. Preliminary results support the use of RTX in patients with pure membranous LN and immunoglobulin-mediated membranoproliferative glomerulonephritis (MPGN), but not in patients with class III/IV LN or complement-mediated MPGN. No conclusion can be drawn in idiopathic focal segmental glomerulosclerosis (FSGS) and anti-glomerular basement membrane antibody glomerulonephritis (anti-GBM GN) because studies are small, heterogeneous, and scarce. Lastly, immunosuppression including RTX is not particularly useful in IgA nephropathy. This review presents the general background, outcomes, and safety for RTX treatment in different glomerulopathies. In this regard, we describe randomized controlled trials (RCTs) performed in adults, whenever possible. A literature search was performed using clinicaltrials.gov and PubMed.

Rituximab use in adult glomerulopathies and its rationale

Glomerulopathies are one of the leading causes of end-stage renal disease. In the last years, clinical research has made significant contributions to the understanding of such conditions. Recently, rituximab (RTX) has appeared as a reasonably safe treatment. The Kidney Disease: Improving Global Outcomes guidelines (KDIGO) recommended RTX only as initial treatment in antineutrophil cytoplasm antibody associated vasculitis (AAV) and in non-responders patients with lupus nephritis (LN), but these guidelines have not been updated since 2012. Nowadays, RTX seems to be at least as effective as other immunosuppressive regimens in idiopathic membranous nephropathy (IMN). In minimal-change disease, (MCD) this drug might allow a long-lasting remission period in steroid-dependent or frequently relapsing patients. Preliminary results support the use of RTX in patients with pure membranous LN and immunoglobulin-mediated membranoproliferative glomerulonephritis (MPGN), but not in patients with class III/IV LN or complement-mediated MPGN. No conclusion can be drawn in idiopathic focal segmental glomerulosclerosis (FSGS) and anti-glomerular basement membrane antibody glomerulonephritis (anti-GBM GN) because studies are small, heterogeneous, and scarce. Lastly, immunosuppression including RTX is not particularly useful in IgA nephropathy. This review presents the general background, outcomes, and safety for RTX treatment in different glomerulopathies. In this regard, we describe randomized controlled trials (RCTs) performed in adults, whenever possible. A literature search was performed using clinicaltrials.gov and PubMed.

Prognosis and future developments in vasculitis

The prognosis of ANCA-associated vasculitis has been transformed in recent years. Once it was a set of invariably acute and fatal conditions, but these disorders are currently considered to be chronic diseases. This change is largely attributable to earlier diagnosis and the careful application of immunotherapeutics. However, patients still experience premature mortality, relapse, comorbid ill health and poor quality of life. Mortality rates in large-vessel vasculitis are not comparable; however, morbidity and poor patient outcomes prevail. Toxicity secondary to glucocorticoids represents a common driver of poor outcomes across systemic vasculitis. The main thrust of future treatment strategies is to reduce if not eliminate exposure to these agents.

Targeting the tyrosine kinase signalling pathways for treatment of immune-mediated glomerulonephritis: from bench to bedside and beyond

Glomerulonephritis (GN) affects patients of all ages and is an important cause of morbidity and mortality. Non-selective immunosuppressive drugs have been used in immune-mediated GN but often result in systemic side effects and occasionally fatal infective complications. There is increasing evidence from both preclinical and clinical studies that abnormal activation of receptor and non-receptor tyrosine kinase signalling pathways are implicated in the pathogenesis of immune-mediated GN. Activation of spleen tyrosine kinase (SYK), Bruton's tyrosine kinase (BTK), platelet-derived growth factor receptor (PDGFR), epidermal growth factor receptor (EGFR) and discoidin domain receptor 1 (DDR1) have been demonstrated in anti-GBM disease. SYK is implicated in the pathogenesis of ANCA-associated GN. SYK, BTK, PDGFR, EFGR, DDR1 and Janus kinase are implicated in the pathogenesis of lupus nephritis. A representative animal model of IgA nephropathy (IgAN) is lacking. Based on the results from in vitro and human renal biopsy study results, a phase II clinical trial is ongoing to evaluate the efficacy and safety of fostamatinib (an oral SYK inhibitor) in high-risk IgAN patient. Various tyrosine kinase inhibitors (TKIs) have been approved for cancer treatment. Clinical trials of TKIs in GN may be justified given their long-term safety data. In this review we will discuss the current unmet medical needs in GN treatment and research as well as the current stage of development of TKIs in GN treatment and propose an accelerated translational research approach to investigate whether selective inhibition of tyrosine kinase provides a safer and more efficacious option for GN treatment.

Kv1.3 Channel Blockade Modulates the Effector Function of B Cells in Granulomatosis with Polyangiitis

B cells are central to the pathogenesis of granulomatosis with polyangiitis (GPA), exhibiting both (auto)antibody-dependent and -independent properties. Class-switched memory B cells in particular are a major source of pathogenic autoantibodies. These cells are characterized by high expression levels of Kv1.3 potassium channels, which may offer therapeutic potential for Kv1.3 blockade. In this study, we investigated the effect of the highly potent Kv1.3 blocker ShK-186 on B cell properties in GPA in vitro. Circulating B cell subsets were determined from 33 GPA patients and 17 healthy controls (HCs). Peripheral blood mononuclear cells (PBMCs) from GPA patients, and HCs were stimulated in vitro in the presence and absence of ShK-186. The production of total and antineutrophil cytoplasmic antibodies targeting proteinase 3 (PR3-ANCA) IgG was analyzed by enzyme-linked immunosorbent assay and Phadia EliA, respectively. In addition, effects of ShK-186 on B cell proliferation and cytokine production were determined by flow cytometry. The frequency of circulating switched and unswitched memory B cells was decreased in GPA patients as compared to HC. ShK-186 suppressed the production of both total and PR3-ANCA IgG in stimulated PBMCs. A strong decrease in production of tumor necrosis factor alpha (TNFα), interleukin (IL)-2, and interferon gamma was observed upon ShK-186 treatment, while effects on IL-10 production were less pronounced. As such, ShK-186 modulated the TNFα/IL-10 ratio among B cells, resulting in a relative increase in the regulatory B cell pool. ShK-186 modulates the effector functions of B cells in vitro by decreasing autoantibody and pro-inflammatory cytokine production. Kv1.3 channel blockade may hold promise as a novel therapeutic strategy in GPA and other B cell-mediated autoimmune disorders.

Infectious complications of rituximab therapy in renal disease

Rituximab, an anti-CD20 monoclonal antibody, was originally used to treat B-cell malignancies. Its use has significantly increased in recent years, as it is now also used to treat a variety of autoimmune diseases including rheumatoid arthritis and ANCA-associated vasculitis (AAV). Initial studies suggested that the adverse effects of rituximab were minimal. Though the risk of malignancy with rituximab-based immunosuppressive regimens appears similar to that of the general population, there are now concerns regarding the risk of infectious complications. Rituximab has been associated with serious infections, including Pneumocystis jiroveci pneumonia (PJP) and the reactivation of hepatitis B virus (HBV) and tuberculosis (TB). The risk of infection appears to be the result of a variety of mechanisms, including prolonged B-cell depletion, B-cell–T-cell crosstalk, panhypogammaglobulinaemia, late-onset neutropenia and blunting of the immune response after vaccination. Importantly, the risk of infectious complications is also related to individual patient characteristics and the indication for rituximab. Individualization of treatment is, therefore, crucial. Particular attention should be given to strategies to minimize the risk of infectious complications, including vaccinating against bacterial and viral pathogens, monitoring white cell count and immunoglobulin levels, prophylaxis against PJP and screening for HBV and TB.

Cathepsin S inhibition combines control of systemic and peripheral pathomechanisms of autoimmune tissue injury

Cathepsin(Cat)-S processing of the invariant chain-MHC-II complex inside antigen presenting cells is a central pathomechanism of autoimmune-diseases. Additionally, Cat-S is released by activated-myeloid cells and was recently described to activate protease-activated-receptor-(PAR)-2 in extracellular compartments. We hypothesized that Cat-S blockade targets both mechanisms and elicits synergistic therapeutic effects on autoimmune tissue injury. MRL-(Fas)lpr mice with spontaneous autoimmune tissue injury were treated with different doses of Cat-S inhibitor RO5459072, mycophenolate mofetil or vehicle. Further, female MRL-(Fas)lpr mice were injected with recombinant Cat-S with/without concomitant Cat-S or PAR-2 blockade. Cat-S blockade dose-dependently reversed aberrant systemic autoimmunity, e.g. plasma cytokines, activation of myeloid cells and hypergammaglobulinemia. Especially IgG autoantibody production was suppressed. Of note (MHC-II-independent) IgM were unaffected by Cat-S blockade while they were suppressed by MMF. Cat-S blockade dose-dependently suppressed immune-complex glomerulonephritis together with a profound and early effect on proteinuria, which was not shared by MMF. In fact, intravenous Cat-S injection induced severe glomerular endothelial injury and albuminuria, which was entirely prevented by Cat-S or PAR-2 blockade. In-vitro studies confirm that Cat-S induces endothelial activation and injury via PAR-2. Therapeutic Cat-S blockade suppresses systemic and peripheral pathomechanisms of autoimmune tissue injury, hence, Cat-S is a promising therapeutic target in lupus nephritis.

Rituximab for immunologic renal disease: What the nephrologist needs to know

Rituximab (RTX), a chimeric, monoclonal anti-CD20 antibody, is increasingly used in immune-mediated renal diseases. While licensed in the induction treatment of ANCA-associated vasculitis, it represents one of the most commonly prescribed off-label drugs. Much of the information regarding its safety has been drawn from experience in hematology and rheumatology. Ample evidence illustrates the safety of RTX, however, rare but serious adverse events have emerged that include progressive multifocal leucoencephalopathy and hepatitis B reactivation. Moderate to severe hypogammaglobulinemia and late-onset neutropenia following RTX therapy confer an increased infectious risk and factors predicting these side effects (i.e. a genetic basis) need to be identified. Nephrologists initiating RTX need to bear in mind that long-term risks and optimal dosing for many renal indications remain unclear. Special considerations must be given when RTX is used in women of childbearing age. We summarize practical aspects concerning the use of RTX. This review will provide nephrologists with information to guide their use of RTX alerting them to safety risks and the need for patient counselling.

Glomerular Diseases: Registries and Clinical Trials

Nephrology has conducted few high-quality clinical trials, and the trials that have been conducted have not resulted in the approval of new treatments for primary or inflammatory glomerular diseases. There are overarching process issues that affect the conduct of all clinical trials, but there are also some specialty-specific issues. Within nephrology, primary glomerular diseases are rare, making adequate recruitment for meaningful trials difficult. Nephrologists need better ways, beyond histopathology, to phenotype patients with glomerular diseases and stratify the risk for progression to ESRD. Rigorous trial design is needed for the testing of new therapies, where most patients with glomerular diseases are offered the opportunity to enroll in a clinical trial if standard therapies have failed or are lacking. Training programs to develop a core group of kidney specialists with expertise in the design and implementation of clinical trials are also needed. Registries of patients with glomerular disease and observational studies can aid in the ability to determine realistic estimates of disease prevalence and inform trial design through a better understanding of the natural history of disease. Some proposed changes to the Common Rule, the federal regulations governing the ethical conduct of research involving humans, and the emerging use of electronic health records may facilitate the efficiency of initiating multicenter clinical trials. Collaborations among academia, government scientific and regulatory agencies, industry, foundations, and patient advocacy groups can accelerate therapeutic development for these complex diseases.

Outcomes of Elderly Patients with Anti-Neutrophil Cytoplasmic Autoantibody-Associated Vasculitis Treated with Immunosuppressive Therapy

BACKGROUND/AIMS

Anti-neutrophil cytoplasmic autoantibody-associated vasculitis (AAV) is a cause of biopsy-proven acute kidney injury, more common in the elderly. Treatment requires immunosuppression, which can have significant toxic effects. The aim of this study was to assess whether morbidity and mortality that are associated with immunosuppression for AAV varied with age.

METHODS

A retrospective review of 232 patients given induction therapy with prednisolone and cyclophosphamide was conducted. Information was collected on baseline characteristics (including requirement for dialysis at presentation) and the occurrence of leukopenia, infection, end-stage renal disease and death during follow-up.

RESULTS

Median follow-up was 51 months. Older patients (aged ≥70 years) were treated with lower total cyclophosphamide doses than those aged <70 years (mean 7.3 g (SD 4.4) vs. 10.7 g (SD 7.4), respectively). Increasing age was associated with an increased risk of leukopenia (odds ratio (OR) 1.50; 95% confidence interval (CI) 1.20-1.86; p < 0.001), and older patients were more likely to develop infections in the first year (OR 1.87; 95% CI 1.1-3.2). Older patients were also significantly more likely to require dialysis at presentation (OR 1.66; 95% CI 1.13-2.5) and longer term. After multivariable adjustment, age and requirement for dialysis at presentation were significant predictors of death (hazard ratio (HR) per year of age 1.07; 95% CI 1.03-1.11; p < 0.001 and HR 2.2; 95% CI 1.10-4.38; p = 0.03, respectively).

CONCLUSIONS

Among patients treated with prednisolone and cyclophosphamide, increasing age and dialysis dependency were associated with worse survival. Older patients were more likely to develop treatment-related complications despite lower cumulative doses of immunosuppression. Morbidity and mortality associated with treatment must therefore be carefully balanced against that associated with the disease process itself.

Moderator's view: Cyclophosphamide in lupus nephritis

Mycophenolate mofetil was recently accepted as the effective induction treatment of lupus nephritis, with the potential to replace cyclophosphamide or at least expand our therapeutic armamentarium in patients with this lifelong disease often requiring repeated induction treatment of its relapses. Compared with cyclophosphamide, mycophenolate may be more effective in black patients, and the risk of gonadotoxicity may be significantly lower in mycophenolate-treated subjects. However, experience with mycophenolate in severe lupus nephritis is still limited and we also have insufficient data on the long-term outcome of mycophenolate-treated patients. Treatment with mycophenolate is more expensive than with cyclophosphamide, which may limit its use, especially in low- and middle-income countries. The efficacy of mycophenolate mofetil may be more dependent on the patient's compliance compared with intravenous cyclophosphamide pulses. Low-dose cyclophosphamide remains an effective and relatively safe induction treatment of active lupus nephritis, but to decrease its cumulative toxicity, repeated exposure to cyclophosphamide in relapsing patients should be (if possible) avoided.

Biologic agents in the treatment of glomerulonephritides

Current immunosuppression strategies in the treatment of glomerulonephritides remain unsatisfactory, especially in glomerular diseases that are frequently relapsing or are resistant to treatment. Toxicities associated with the use of drugs with non-specific targets for the immune response result in treatment non-compliance, and increase morbidity and mortality in these patients. Advances in our understanding of the immunopathogenesis of glomerulonephritis and the availability of biologics have led to their successful use in the treatment of immune-mediated glomerular diseases. Biologics are usually very large complex molecules, often produced using recombinant DNA technology and manufactured in a living system such as a microorganism, or plant or animal cells. They are novel agents that can target specific immune cell types, cytokines or immune pathways involved in the pathogenesis of these disorders. It is attractive to consider that, given their specific mode of action, these agents can potentially offer a more directed and effective immunosuppression, with side-effect profiles that are much more desirable. However, there have been few randomized controlled trials comparing biologic agents to conventional immunosuppression, and in many of these studies the side-effect profiles have been disappointingly similar. In this review, we will examine the rationale, efficacy and safety of some commonly used biologics in the treatment of primary and secondary glomerulonephritides. We will also discuss some of the key challenges that may be encountered with the use of biologics in treating glomerulonephritis in the future.

Adverse events and infectious burden, microbes and temporal outline from immunosuppressive therapy in antineutrophil cytoplasmic antibody-associated vasculitis with native renal function

BACKGROUND

Disease control in anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV) with immunosuppression is effective but burdened by adverse events, especially infections. The study goal was to evaluate risks and types of infections in patients with AAV.

METHODS

Biopsy-proven AAV patients (diagnosed 1/1991-6/2011) followed in an inception cohort were evaluated for adverse events. Severe infections (requiring intravenous antibiotics, intensive care unit, or causing death) were recorded. Infection number was grouped as none, 1-2 or ≥3. Cox regression was used to estimate hazard ratios with 95% confidence intervals.

RESULTS

A total of 489 patients (median age 59; 47% female, 55% myeloperoxidase-ANCA) were followed for 2.8 years (median). At 1, 2 and 5 years cumulative incidence of infection was 51, 58 and 65% and severe infection was 22, 23 and 26%. Pulmonary and upper respiratory infections were most common (42 and 30% ever experienced each, respectively), highest in the first 3 months. Staphylococcus aureus was most frequently seen among positive cultures (41%, 78 S. aureus/192 total positive cultures), and only one Pneumocystis jiroveci pneumonia (6 weeks into treatment). All-cause death in 12 months was associated with infections (% deaths: 0 infections 3%; 1-2 infections 10%, ≥3 infections 13%, P = 0.002). Controlling for age, sex and kidney function, patients with severe infections were 4.2 times more likely to die within 12 months (95% CI 2.0-8.7; P = 0.001).

CONCLUSIONS

More infections increase the risk of a severe infection which increases risk of all-cause mortality. Respiratory and S. aureus infections are dominant. Targeted prophylactic therapy could decrease morbidity.

Moderator's view: Should all patients with ANCA-associated vasculitis be primarily treated with rituximab?

Experience with rituximab in patients with new ANCA-associated vasculitis (AAV) is still very limited, especially in patients with severe (organ- or life-threatening) AAV. Rituximab may be more effective in anti-PR3 AAV, but potentially less effective in some granulomatous manifestations of AAV. We do not know what the response is to rituximab on the tissue level. Rituximab induction needs to be followed by maintenance treatment, and potentially very long rituximab maintenance may result in higher risk of rituximab-related complications (e.g. decrease in IgG levels). Long-term experience with rituximab in AAV is insufficient. Treatment with rituximab is more expensive than the standard treatment with cyclophosphamide and corticosteroids and seems to be cost-effective only in patients primarily treated with cyclophosphamide. Rituximab can be used in some newly diagnosed patients with AAV (e.g. women with child-bearing potential, or patients with active vasculitis and severe infection), but with the available information, it may be too early to use it as a first-line treatment in all new AAV patients.

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.

Rituximab versus azathioprine for maintenance in ANCA-associated vasculitis

BACKGROUND

The combination of cyclophosphamide and glucocorticoids leads to remission in most patients with antineutrophil cytoplasm antibody (ANCA)-associated vasculitides. However, even when patients receive maintenance treatment with azathioprine or methotrexate, the relapse rate remains high. Rituximab may help to maintain remission.

METHODS

Patients with newly diagnosed or relapsing granulomatosis with polyangiitis, microscopic polyangiitis, or renal-limited ANCA-associated vasculitis in complete remission after a cyclophosphamide-glucocorticoid regimen were randomly assigned to receive either 500 mg of rituximab on days 0 and 14 and at months 6, 12, and 18 after study entry or daily azathioprine until month 22. The primary end point at month 28 was the rate of major relapse (the reappearance of disease activity or worsening, with a Birmingham Vasculitis Activity Score >0, and involvement of one or more major organs, disease-related life-threatening events, or both).

RESULTS

The 115 enrolled patients (87 with granulomatosis with polyangiitis, 23 with microscopic polyangiitis, and 5 with renal-limited ANCA-associated vasculitis) received azathioprine (58 patients) or rituximab (57 patients). At month 28, major relapse had occurred in 17 patients in the azathioprine group (29%) and in 3 patients in the rituximab group (5%) (hazard ratio for relapse, 6.61; 95% confidence interval, 1.56 to 27.96; P=0.002). The frequencies of severe adverse events were similar in the two groups. Twenty-five patients in each group (P=0.92) had severe adverse events; there were 44 events in the azathioprine group and 45 in the rituximab group. Eight patients in the azathioprine group and 11 in the rituximab group had severe infections, and cancer developed in 2 patients in the azathioprine group and 1 in the rituximab group. Two patients in the azathioprine group died (1 from sepsis and 1 from pancreatic cancer).

CONCLUSIONS

More patients with ANCA-associated vasculitides had sustained remission at month 28 with rituximab than with azathioprine. (Funded by the French Ministry of Health; MAINRITSAN ClinicalTrials.gov number, NCT00748644; EudraCT number, 2008-002846-51.).