Rituximab in childhood systemic lupus erythematosus refractory to conventional immunosuppression: case report

Anti-vimentin antibodies: a unique antibody class associated with therapy-resistant lupus nephritis

Background

Tubulointerstitial inflammation (TII) in lupus nephritis is associated with a worse prognosis. Vimentin, a filamental antigen, is commonly targeted by in situ activated B-cells in TII. The prognostic importance of high serum anti-vimentin antibodies (AVAs) in lupus nephritis and their relationship with common lupus autoantibody specificities is unknown. Herein we investigated associations between AVA isotypes, other autoantibodies, and response to mycophenolate mofetil (MMF) in the presence or absence of rituximab.

Methods

The Translational Research Initiative in the Department of Medicine (TRIDOM) cross-sectional cohort of 99 lupus patients was assayed for IgG-, IgA- and IgM- AVAs, lupus-associated and rheumatoid arthritis-associated antibodies, and hierarchically clustered. Serum from baseline, 26 and 52 weeks from 132 Lupus Nephritis Assessment with Rituximab (LUNAR) trial enrolled lupus nephritis patients was also analysed and correlated with renal function up to week 78.

Results

In TRIDOM, AVAs, especially IgM AVAs, clustered with IgG anti-dsDNA and away from anti-Sm and -RNP and rheumatoid arthritis-associated antibodies. In LUNAR at baseline, AVAs correlated weakly with anti-dsDNA and more strongly with anticardiolipin titers. Regardless of treatment, IgG-, but not IgM- or IgA-, AVAs were higher at week 52 than at baseline. In contrast, anti-dsDNA titers declined, regardless of therapeutic regime. High IgG AVA titers at entry predicted less response to therapy.

Conclusion

AVAs, especially IgG AVAs, are unique in distribution and response to therapy compared with other commonly measured autoantibody specificities. Furthermore, high-titer IgG AVAs identify lupus nephritis patients resistant to conventional therapies. These data suggest that AVAs represent an independent class of prognostic autoantibodies.

Enhanced activity of Akt in Teff cells from children with lupus nephritis is associated with reduced induction of tumor necrosis factor receptor-associated factor 6 and increased OX40 expression

OBJECTIVE

The breakdown of peripheral tolerance mechanisms is central to the pathogenesis of systemic lupus erythematosus (SLE). Although true Treg cells in patients with SLE exhibit intact suppressive activity, Teff cells are resistant to suppression. The underlying mechanisms are incompletely understood. This study was undertaken to examine the Akt signaling pathway and molecules that may alter its activity in T cells in lupus patients.

METHODS

The Akt pathway and its regulators were analyzed in Teff and Treg cells from children with lupus nephritis and controls using flow cytometry and real-time quantitative polymerase chain reaction. T cell proliferation was assessed by analysis of 5,6-carboxyfluorescein succinimidyl ester dilution.

RESULTS

CD4+CD45RA-FoxP3(low) and FoxP3- Teff cells from children with lupus nephritis expressed high levels of activated Akt, resulting in the down-regulation of the proapoptotic protein Bim and an enhanced proliferative response. The induction of tumor necrosis factor receptor-associated factor 6 (TRAF6) was impaired, and TRAF6 levels inversely correlated with Akt activity. Although the expression of OX40 was enhanced on Teff cells from children with lupus nephritis compared to controls, OX40 stimulation failed to significantly increase TRAF6 expression in cells from patients, in contrast to those from healthy controls, but resulted in further increased Akt activation that was reversed by blockade of OX40 signaling. Moreover, inhibition of Akt signaling markedly decreased the proliferation of Teff cells from lupus patients.

CONCLUSION

Our findings indicate that hyperactivation of the Akt pathway in Teff cells from children with lupus nephritis is associated with reduced induction of TRAF6 and up-regulation of OX40, which may cause Teff cell resistance to Treg cell-mediated suppression.

Prospective observational single-centre cohort study to evaluate the effectiveness of treating lupus nephritis with rituximab and mycophenolate mofetil but no oral steroids

OBJECTIVES

Lupus nephritis (LN) is a serious complication of systemic lupus erythematosus (SLE). All current treatment regimens include oral steroids, which are associated with severe adverse events and long-term damage. We have piloted a steroid-avoiding protocol (rituxilup) for the treatment of biopsy-proven active International Society of Nephrology/Renal Pathology Society (ISN/RPS) class III, IV, or class V LN.

METHODS

We report the findings from the first 50 consecutive patients, treated with 2 doses of rituximab (1 g) and methyl prednisolone (500 mg) on days 1 and 15, and maintenance treatment of mycophenolate mofetil. Patients on maintenance steroids or with life-threatening SLE or requiring dialysis were excluded. Renal remission was defined as serum creatinine no greater than 15% above baseline; complete biochemical remission (CR) was defined as urine protein : creatinine ratio (PCR)<50 mg/mmol or partial remission (PR) if PCR>50 mg/mmol but non-nephrotic and >50% reduction.

RESULTS

A total of 45 (90%) patients achieved CR or PR by a median time of 37 weeks (range 4-200). Overall, 72% (n=36) achieved CR (median time 36 weeks (11-58)) and a further 18% (n=9) achieved persistent PR (median time 32 weeks (19-58)). By 52 weeks, CR and PR had been achieved in 52% (n=26) and 34% (n=17) respectively. In all, 12 relapses occurred in 11 patients, at a median time of 65.1 weeks (20-112) from remission. A total of 6/50 patients had systemic flares. Of the 45 responders, only 2 required >2 weeks of oral steroids. Adverse events were infrequent; 18% were admitted, 10% for an infective episode.

CONCLUSIONS

The rituxilup cohort demonstrates that oral steroids can be safely avoided in the treatment of LN. If findings are confirmed, it could mark a step change in the approach to the treatment of LN.

Management of systemic lupus erythematosus in Chinese patients

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

Successful treatment of severe juvenile microscopic polyangiitis with rituximab

Microscopic polyangiitis (MPA) previously called hypersensitivity angiitis is a systemic necrotizing vasculitis affecting predominantly small vessels. MPA involves multiple organ systems including the lung, the kidneys, the joints, and the skin. MPA mostly affects adults in their fourth and fifth decade of life. MPA and Wegener;s granulomatosis are grouped together as ANCA-associated vasculitis. MPA is associated with high titre of myeloperoxidase antineutrophil cytoplasmic antibodies (MPO)-ANCA. We present a 14-year-old female patient presented with MPA. She was treated with steroids and cyclophosphamide. After the complication of severe lung involvement, rituximab was administered as immune-modulating treatment. The MPA came to remission. This is the first report of a pediatric patient with MPA treated with rituximab. Rituximab might be a potential therapeutic option for relapsing ANCA associated vasculitis in childhood.

Long-term efficacy and safety of quadruple therapy in childhood diffuse proliferative lupus nephritis

In this study, we evaluated the frequency, clinical presentation, treatment protocols, prognostic factors, and outcome in children with diffuse proliferative lupus nephritis (DPLN). Between June 1990 and December 2004, 46 patients were diagnosed to have systemic lupus erythematosus (SLE), and 26 of them (56.5%) were found to have DPLN. Renal manifestations were present in 25 patients, and the majority of them presented with severe renal findings, such as nephrotic syndrome and renal failure. All patients were given a quadruple therapy protocol including 6-12 monthly courses of methyl prednisolone pulse therapy combined with oral prednisolone, oral cyclophosphamide, azathioprine, and dipyridamole. Nineteen of these patients were regularly followed up with a mean follow-up period of 5.9 years. Complete remission was achieved in 15 of 19 patients, and chronic renal failure developed in four patients. Renal survival rate was calculated to be 78.9% at the end of 5, 10, and 14 years. Although nephrotic range proteinuria, hypoalbuminemia, renal failure, and activity index above 12/24 at presentation seemed to be associated with poor prognosis, no significant difference could be found. Hypertension and chronicity index greater than 6/12 were found to be bad prognostic predictors. We concluded that satisfactory results were achieved with our quadruple therapy protocol; thus, more aggressive and expensive therapies can be avoided and preserved for more serious and persistent diseases.

Rituximab therapy for juvenile-onset systemic lupus erythematosus

Rituximab (RTX), an anti-CD20 monoclonal antibody, has been proposed for use in the therapy of systemic lupus erythematosus (SLE). We present the initial long-term experience of the safety and efficacy of rituximab for treatment of SLE in children. Eighteen patients (mean age 14 +/- 3 years) with severe SLE were treated with rituximab after demonstrating resistance or toxicity to conventional regimens. There was a predominance of female (16/18) and ethnic African (13/18) patients. All had lupus nephritis [World Health Organization (WHO) classes 3-5] and systemic manifestations of vasculitis. Clinical disease activity of the SLE was scored with the SLE-disease activity index 2K (SLEDAI-2K). Patients were followed-up for an average of 3.0 +/- 1.3 years (range 0.5 to 4.8 years). B-cell depletion occurred within 2 weeks in all patients and persisted for up to 1 year in some. Clinical activity scores, double-stranded DNA (dsDNA) antibodies, renal function and proteinuria [urine protein to creatinine ratio (Upr/cr)] improved in 93% of the patients. Five patients required multiple courses of RTX for relapse, with B-cell repopulation. One died of infectious endocarditis related to severe immunosuppression. In conclusion, our data support the efficacy of rituximab as adjunctive treatment for SLE in children. Although rituximab was well tolerated by the majority of patients, randomized controlled trials are required to establish its long-term safety and efficacy.

New treatment strategies for proliferative lupus nephritis: keep children in mind!

Renal involvement is frequent in children with systemic lupus erythematosus (SLE) and carries significant short and long-term morbidity. Treatment strategy in proliferative glomerulonephritis relies mainly on studies in adult patients where conventional treatment regimens including high doses of cyclophosphamide (CYC) and steroids may cause severe side effects. New strategies including sequential therapies of various combinations of low dose CYC, calcineurine inhibitors (cyclosporine or tacrolimus), mycophenolate mofetil, azathioprine, rituximab are now under investigation in adult patients with very few data in children. Organization of international registries and controlled trials in children with lupus nephritis is mandatory to determine long term prognosis and to validate less toxic therapy regimens in childhood.

Update on therapeutic monoclonal antibodies

Monoclonal antibodies are among the most important class of drugs introduced into the therapeutic armamentarium since the introduction of antimicrobials in the 1930s. The first therapeutic monoclonal antibody, the anti T-cell monoclonal antibody OKT4, was licensed in 1986. Since then, 18 additional antibodies have been licensed in the US, with many more in the pipeline. Before 1986, many monoclonal antibodies were available for laboratory studies, notably to identify specific cells in the blood and tissues. This is best illustrated by the cluster designation (CD) system for antigens present on hematopoietic cells, now numbering over 200.

Efficacy of rituximab (anti-CD20) for refractory systemic lupus erythematosus involving the central nervous system

AIM

Neuropsychiatric systemic lupus erythematosus (NPSLE) is a serious treatment-resistant phenotype of systemic lupus erythematosus. A standard treatment for NPSLE is not available. This report describes the clinical and laboratory tests of 10 patients with NPSLE before and after rituximab treatment, including changes in lymphocyte phenotypes.

METHODS

Rituximab was administered at different doses in 10 patients with refractory NPSLE, despite intensive treatment.

RESULTS

Treatment with rituximab resulted in rapid improvement of central nervous system-related manifestations, particularly acute confusional state. Rituximab also improved cognitive dysfunction, psychosis and seizure, and reduced the SLE Disease Activity Index Score at day 28 in all 10 patients. These effects lasted for >1 year in five patients. Flow cytometric analysis showed that rituximab down regulated CD40 and CD80 on B cells and CD40L, CD69 and inducible costimulator on CD4+ T cells.

CONCLUSIONS

Rituximab rapidly improved refractory NPSLE, as evident by resolution of various clinical signs and symptoms and improvement of radiographic findings. The down regulation of functional molecules on B and T cells suggests that rituximab modulates the interaction of activated B and T cells through costimulatory molecules. These results warrant further analysis of rituximab as treatment for NPSLE.

Beneficial effects of rituximab therapy for systemic lupus erythematosus

We report an 11-yr-old girl with systemic lupus erythematosus (SLE) with recurrent flares of skin and systemic manifestations, which were poorly controlled with conventional therapy. Treatment with rituximab, a monoclonal antibody against CD20, was associated with remission of symptoms and a steroid sparing effect that persisted for more than 9 months. Therapy with rituximab appears promising in subjects with SLE.

Emerging drug therapies for systemic lupus erythematosus

Despite the tremendous improvement in survival of systemic lupus erythematosus (SLE) in the past few decades, manifestations of the disease that are refractory to conventional therapies and treatment-related complications are still major causes of mortality and morbidity. In recent years, we have seen an explosive development of newer therapeutic modalities for various rheumatic diseases including SLE. Novel therapies for SLE should aim at targeting more specifically the immunopathogenetic pathways to achieve higher efficacy and reduce therapy related toxicities. This article reviews the emerging therapeutic modalities that have been used or are being tried in patients with SLE.

Drug insight: rituximab in renal disease and transplantation

Rituximab, a monoclonal antibody directed against the CD20 molecule found on pre-B cells and mature B cells (but not on plasma cells), was introduced in the late 1990s for the treatment of non-Hodgkin's lymphoma. Recently, this antibody has been used to treat autoimmune diseases, especially those associated with a prominent humoral component and with potentially pathogenic autoantibodies. Small cohort studies have indicated that rituximab could have an important role in the management of these disorders. Rituximab has also been utilized in the transplant setting, to diminish levels of alloreactive antibodies in highly sensitized patients, to manage ABO-incompatible transplants, and to treat rejection associated with B cells and antibodies. The exact mechanism by which rituximab exerts its effects in autoimmunity and transplantation remains unclear, as specific autoantibody or alloantibody levels often seem not to diminish in parallel with clinical improvement. A role for rituximab in depleting B cells and compromising their antigen-presenting function seems likely; rituximab might also inhibit T-cell activation. A synergistic effect has been noted in vitro following administration of corticosteroids to B-cell lines, with accentuation of B-cell cytotoxicity; this observation might be relevant to certain studies, as some regimens have utilized both agents simultaneously. This article reviews the current use of rituximab in renal disease and transplantation, and includes discussion of the drug's potential role in novel therapeutic protocols.

Prognosis of lupus membranous nephropathy in children

The occurrence of membranous nephropathy in pediatric series of systemic lupus erythematosus has been reported only rarely, probably due to a very low frequency. One hundred fifty-four children who were seen in 100 French pediatric centers between January 2002 and April 2005 were included. Fifteen (12 girls and three boys) out of the 81 (18.5 %) children with renal involvement presented histological features of membranous nephropathy. Their ages ranged from six to 15 years old (mean=11.3) at the age of SLE diagnosis and 8/15 children were of African origin. Isolated membranous nephropathy was observed in nine patients, of whom five patients displayed a complete recovery following immunosuppressive treatment. Associated proliferative lesions were observed on the first kidney specimen in two patients and in a further renal biopsy in four other patients, leading to a less favorable course of lupus nephropathy.

Therapeutic options for resistant lupus nephritis

OBJECTIVES

To summarize the therapeutic options for proliferative and membranous lupus nephritis that is resistant to conventional treatment.

METHODS

Treatment trials in human lupus nephritis from years 1985 to 2005 that have been published in the English literature were searched by Medline using the keywords "lupus," "nephritis," "glomerulonephritis," "renal," "refractory," "resistant," "recalcitrant," "cyclophosphamide," "mycophenolate," "cyclosporin," "tacrolimus," "leflunomide," "intravenous immunoglobulin," "apheresis," "plasmapheresis," "immunoadsorption," "marrow transplantation," "stem cell transplantation," "immunoablative," "rituximab," and "biologics." Laboratory, histological, and nonrenal lupus studies were excluded.

RESULTS

There is no universal definition of treatment resistance in lupus nephritis. Controlled trials in refractory lupus nephritis are largely unavailable. Open-labeled studies have reported success of newer immunosuppressive drugs, immunomodulatory therapies, and the biological agents such as mycophenolate mofetil (MMF), calcineurin inhibitors, leflunomide, intravenous immunoglobulin, immunoadsorption, and rituximab in the treatment of cyclophosphamide (CYC) resistant proliferative lupus nephritis. More aggressive CYC regimens have been used in lupus nephritis, but at the expense of more toxicities. For membranous lupus nephritis (MLN), a combination of corticosteroids with either azathioprine, chlorambucil, cyclosporin A, MMF, or CYC is initially effective in two-thirds of patients. More aggressive and costly regimens should be reserved for truly refractory disease with persistent nephrotic syndrome or declining renal function. Evidence regarding the efficacy of MMF in refractory MLN is conflicting and controlled trials are necessary to resolve the controversy.

CONCLUSIONS

The treatment of refractory lupus nephritis remains anecdotal. An international consensus in the renal response criteria should be developed and validated so that controlled trials can be performed to compare the efficacy of various treatment modalities.

Rituximab therapy for childhood-onset systemic lupus erythematosus

OBJECTIVE

To describe the safety and efficacy of rituximab in the treatment of childhood-onset systemic lupus erythematosus (SLE).

STUDY DESIGN

We conducted a French multicenter retrospective study of childhood-onset SLE treated with rituximab.

RESULTS

Eleven girls with severe SLE, including 8 girls with class IV or V lupus nephritis, 2 girls with severe autoimmune cytopenia, and 1 girl with antiprothrombin antibody with severe hemorrhage, were treated with rituximab. The mean age at onset of rituximab treatment was 13.9 years. Patients received 2 to 12 intravenous infusions of rituximab (350-450 mg/m2/infusion), with corticosteroids. Six patients also received different standard immunosuppressive agents, including Cyclophosphamide (2 patients). Remission was achieved in 6 of 8 patients with lupus nephritis and in the 2 patients with autoimmune cytopenia. Steroid therapy was tapered in 5 patients who responded to treatment, and low-dose prednisone treatment was maintained in 1 patient. The mean follow-up period was 13.2 months (range, 6-26 months), and remission lasted in all who patients who responded to treatment, except 1 patient who was successfully retreated with a second course of rituximab. Anti-double-stranded DNA antibody levels decreased in 6 of 11 patients, and anticardiolipin antibody levels decreased in 3 of 4 patients. Severe adverse events developed in 5 patients. Effective depletion of peripheral blood B cells was observed in 7 of 8 patients who were examined, and this paralleled the remission.

CONCLUSION

Rituximab may be an effective co-therapy; however, further investigations are required because severe adverse events occurred in 45% of the patients in this study.

Adolescent development and SLE

Adolescence is a time of profound biological and psychosocial change. The management of a complex chronic condition such as systemic lupus erythematosus (SLE) during this period is a challenging but rewarding task for the clinician. Early diagnosis and optimal disease control is essential in order to facilitate normal adolescent development and minimize long-term disease sequelae. Current treatment regimens are associated with significant toxicity in young people, and there is a need for new, less toxic regimens. There are currently no controlled therapeutic studies in adolescents with SLE. Those involved in the care of these young people must ensure that they have appropriate access to specialist medical services while ensuring that their specific needs as adolescents in the health-care system are addressed.

Rituximab: A promising therapy in systemic lupus erythematosus

Several trials of new immunologic agents in systemic lupus erythematosus (SLE) have recently been undertaken. Rituximab, a chimeric antibody directed against CD20 on B lymphocytes, has emerged as a promising therapy. Based upon preliminary data, clinical efficacy of rituximab has been documented in both pediatric and adult-onset SLE patients. The specific manifestations reported to be beneficially affected include lupus nephritis, arthralgia/arthritis, serositis, cutaneous vasculitis, mucositis, rashes, fatigue and neurologic symptoms. Although rituximab's mechanisms of action are incompletely understood, the effects of rituximab are likely mediated by antibody-dependent cell-mediated cytotoxicity and the induction of apoptosis. The resultant repopulation of B cells, alteration of abnormal B cell homeostasis and down-regulation of co-stimulatory molecules on both B and T cells all likely contribute to clinical efficacy. Good tolerability of rituximab is reported with rare serious side effects. The positive response to rituximab verifies a central role for B cells in SLE. This article highlights the clinical experience of rituximab therapy in both pediatric and adult-onset SLE. These data suggest a promising role for rituximab in the treatment of SLE. Further controlled trials and long-term outcome studies are imperative to further define its clinical application and to improve the care of patients.

Autoimmune mechanisms in children with systemic lupus erythematosus

Although the pathogenesis of SLE remains poorly understood, there is consensus that it involves a combination of genetic, hormonal, and environmental factors. New technologies applied to genomic and gene expression studies have revealed novel gene mutations and cytokine alterations in this disease. Recently, advances in monoclonal antibodies and recombinant DNA technology have resulted in the development of new drugs to arrest disease progression and restore physiologic immune responses without major side effects. Clinical trials to test several of these novel therapies are currently underway.