Abatacept for lupus nephritis: alternative definitions of complete response support conflicting conclusions

Targeted therapies for lupus nephritis: Current perspectives and future directions

ABSTRACT

Lupus nephritis (LN), a severe manifestation of systemic lupus erythematosus, poses a substantial risk of progression to end-stage renal disease, with increased mortality. Conventional therapy for LN relies on broad-spectrum immunosuppressants such as glucocorticoids, mycophenolate mofetil, and calcineurin inhibitors. Although therapeutic regimens have evolved over the years, they have inherent limitations, including non-specific targeting, substantial adverse effects, high relapse rates, and prolonged maintenance and remission courses. These drawbacks underscore the need for targeted therapeutic strategies for LN. Recent advancements in our understanding of LN pathogenesis have led to the identification of novel therapeutic targets and the emergence of biological agents and small-molecule inhibitors with improved specificity and reduced toxicity. This review provides an overview of the current evidence on targeted therapies for LN, elucidates the biological mechanisms of responses and failure, highlights the challenges ahead, and outlines strategies for subsequent clinical trials and integrated immunomodulatory approaches.

Experience with abatacept in refractory lupus nephritis

Lupus nephritis is a major cause of morbidity in patients with systemic lupus erythematosus. Responsiveness to treatment is crucial to avoid chronic kidney disease. New molecules have been developed in recent years to improve renal survival rates. Biological therapies as coadjutant to conventional induction treatment have been tested in randomized clinical trials with heterogeneous results. Like many others biologic therapies, Abatacept has not shown a clear benefit in the context of clinical trials. We present two cases of lupus nephritis patients in whom addition of abatacept resulted in complete remission of the renal disease. The first case described a 49-year-old male with class IV lupus nephritis with nephrotic range proteinuria and high immunological activity refractory to conventional treatment with cyclophosphamide and corticosteroids and multitarget therapy with tacrolimus, mycophenolate mofetil and prednisone. Several biological therapies (rituximab, belimumab and tocilizumab) were unsuccessfully tried, so that abatacept was added to his background multitarget therapy showing complete clinical response. The second case described a 52-year-old female with class IV lupus nephritis treated initially with conventional treatment with partial response. In successive renal flares with nephrotic proteinuria, she showed intolerance to rituximab and refractoriness to voclosporin. Finally, abatacept was added to her background therapy with MMF and PDN showing complete and maintained remission of the disease. In no case the use of abatacept was associated with serious adverse events. Based on our experience, abatacept should be considered as a safe rescue therapy in patients with refractory lupus nephritis and proteinuria with nephrotic range. In addition to this case, we reviewed the use of abatacept in lupus nephritis in the literature.

Urine biomarker score captures response to induction therapy with lupus nephritis

BACKGROUND

The Renal Activity Index for Lupus (RAIL) consists of urine protein assessment of neutrophil gelatinase-associated lipocalin, kidney injury molecule-1, monocyte chemotactic protein 1, adiponectin, hemopexin, and ceruloplasmin, which non-invasively identifies lupus nephritis (LN). We aimed to delineate RAIL scores with inactive versus active LN and changes over time with response to LN induction therapy.

METHODS

There were 128 pediatric patients with systemic lupus erythematosus (SLE) and age-matched healthy controls recruited in a prospective case control study, with kidney biopsy confirmation of LN. Laboratory and clinical information was recorded and urine collected at diagnosis and end of induction and during maintenance therapy. Response to therapy was assessed by repeat kidney biopsy or laboratory parameters. Urine was assayed for RAIL biomarkers and the RAIL score calculated.

RESULTS

Pediatric RAIL (pRAIL) scores from 128 children and young adults with SLE (with/without LN: 70/38) including 25 during LN induction therapy, differentiated clinically active LN from inactive LN or without LN, and controls (all p < 0.0017). pRAIL scores significantly decreased with complete LN remission by 1.07 ± 1.7 (p = 0.03).

CONCLUSIONS

The RAIL biomarkers differentiate LN patients based on activity of kidney disease, with decreases of ≥ 1 in pRAIL scores indicating complete response to induction therapy. Significantly lower RAIL scores in healthy controls and in SLE patients without known LN raise the possibility of subclinical kidney disease. A higher resolution version of the Graphical abstract is available as Supplementary information.

The star target in SLE: IL-17

PURPOSE

The purpose of this review is to discuss the significance of IL-17 in SLE and the potential of IL-17-targeted therapy.

BACKGROUND

Systemic lupus erythematosus (SLE) is an autoimmune disease that can affect many organs and tissues throughout the body. It is characterized by overactive B and T cells and loss of immune tolerance to autoantigens. Interleukin-17 (IL-17) is a cytokine that promotes inflammation and has been implicated in the pathogenesis of several autoimmune diseases as well as inflammatory diseases. In in vitro cellular experiments in lupus susceptible mice or SLE patients, there is substantial evidence that IL-17 is a highly promising therapeutic target.

METHODS

We searched papers from PubMed database using the search terms, such as interleukin-17, systemic lupus erythematosus, treatment targets, T cells, lupus nephritis, and other relevant terms.

RESULTS

We discuss in this paper the molecular mechanisms of IL-17 expression, Th17 cell proliferation, and the relationship between IL-17 and Th17. The significance of IL-17 in SLE and the potential of IL-17-targeted therapy are further discussed in detail.

CONCLUSION

IL-17 has a very high potential for the development as a star target in SLE.

Lupus Nephritis: Improving Treatment Options

Despite improvements in patient and renal death rates following the introduction of potent immunosuppressive drugs in earlier decades, a sizeable fraction of patients with lupus nephritis is burdened with suboptimal or delayed responses, relapses, chronic use of glucocorticoids and accrual of renal (chronic renal insufficiency) and extra-renal organ damage. The recently approved combinatory treatments comprising belimumab or voclosporin added to conventional agents, especially mycophenolate, hold promise for further improving disease outcomes and enabling a faster steroid tapering, thus being relevant to the treat-to-target context. However, it remains uncertain whether these dual regimens should become the first-line choice for all patients or instead be prioritized to certain subgroups. In the present article, we summarize the existing lupus nephritis management recommendations, followed by a critical appraisal of the randomized trials of belimumab and voclosporin, as well as the available data on obinutuzumab and other novel compounds under development. We conclude that pending the identification of accurate clinical, histological, or translational predictors for guiding personalized decisions, it is of utmost importance that lupus nephritis patients are monitored closely with appropriate treatment adjustments aiming at a prompt, deep response to ensure long-term preservation of kidney function.

Defining renal remission in an international cohort of 248 children and adolescents with lupus nephritis

OBJECTIVE

We studied the rate of remission of lupus nephritis (LN) in an international cohort of 248 children and adolescents with biopsy proven LN. Five different definitions from scientific studies and the definitions recommended by the American College of Rheumatology and Kidney Disease Improving Global Outcomes (KDIGO) were used.

METHODS

Anonymized clinical data in patients with biopsy proven LN class ≥ III (International Society of nephrology/Royal Pathology Society-ISN/RPS) diagnosed and treated in the last 10 years in 23 international centers from 10 countries were collected. We compared the rate of patients in complete and partial remission applying the different definitions.

RESULTS

The mean age at diagnosis was 11 years and 4 month and 177 were females.The number of patients in complete and partial remission varied a lot between the different definitions. At 24 months, between 50% and 78.8% of the patients were in full remission as defined by the different criteria. The number of patients in partial remission was low, between 2.3% and 25%. No difference in achieved remission was found between boys and girls or between children and adolescents (P > 0.05). Patients with East Asian ethnicity reached remission more often than other ethnicities (P = 0.03-0.0008). Patients treated in high income countries showed a higher percentage of complete remission at 12 and 24 months (P = 0.002-0.000001).

CONCLUSION

The rate of children and adolescents with LN achieving remission varied hugely with the definition used. Our results give important information for long awaited treatment studies in children and young people.

TACI haploinsufficiency protects against BAFF-driven humoral autoimmunity in mice

Polymorphisms in TACI, a BAFF family cytokine receptor, are linked to diverse human immune disorders including common variable immunodeficiency (CVID) and systemic lupus erythematosus (SLE). Functional studies of individual variants show modest impacts on surface TACI expression and/or downstream signal transduction, indicating that relatively subtle variation in TACI activity can impact human B-cell biology. However, significant complexity underlies TACI biology, including both positive and negative regulation of physiologic and pathogenic B-cell responses. To model these contradictory events, we compared the functional impact of TACI deletion on separate models of murine SLE driven by T cell-independent and -dependent breaks in B-cell tolerance. First, we studied whether reduced surface TACI expression was sufficient to protect against progressive BAFF-mediated systemic autoimmunity. Strikingly, despite a relatively modest impact on surface TACI levels, TACI haploinsufficiency markedly reduced pathogenic RNA-associated autoantibody titers and conferred long-term protection from BAFF-driven lupus nephritis. In contrast, B cell-intrinsic TACI deletion exerted a limited impact of autoantibody generation in murine lupus characterized by spontaneous germinal center formation and T cell-dependent humoral autoimmunity. Together, these combined data provide new insights into TACI biology and highlight how TACI signals must be tightly regulated during protective and pathogenic B-cell responses.

Systemic Lupus Erythematosus Outcome Measures for Systemic Lupus Erythematosus Clinical Trials

The assessment of systemic lupus erythematosus (SLE) disease activity in clinical trials has been challenging. This is related to the wide spectrum of SLE manifestations and the heterogeneity of the disease trajectory. Currently, composite outcome measures are most commonly used as a primary endpoint while organ-specific measures are often used as secondary outcomes. In this article, we review the outcome measures and endpoints used in most recent clinical trials and explore potential avenues for further development of new measures and the refinement of existing tools.

Targeted Biologic Therapy for Systemic Lupus Erythematosus: Emerging Pathways and Drug Pipeline

Following the approval of belimumab, the first drug to be approved for systemic lupus erythematosus (SLE) in over 50 years, advances in our understanding of the pathogenesis of the disease have led to a remarkable number of clinical trials for investigational drugs, each with a unique mechanism of action. These include, but are not limited to, antibodies targeting B or T cells or their interaction, dendritic cells, interferon, and other cytokines. Frustratingly, this boost of studies has not been accompanied by a corresponding success and subsequent approval of novel agents, for reasons only partly attributed to the efficacy of the drugs per se. Successful phase II trials are often followed by failed phase III studies, which typically require many more patients. Nevertheless, recent successes, such as the ustekinumab and baricitinib trials and the positive results from the phase III TULIP-2 study of anifrolumab, provide room for cautious optimism. In this review, we attempt to draw the current landscape of the drug pipeline in SLE, focusing on the rationale behind each drug development, its mechanism of action, and the available preclinical and clinical data. We also highlight lessons learned from failed attempts that have helped to optimize clinical trial design for this challenging disease. We conclude with a look into the future, commenting on the surge of studies in the field of biomarkers and the use of omics technologies in lupus, which aim to pinpoint different disease phenotypes and, ideally, identify subsets of patients with disease that will respond to different biologic drugs.

Leveraging Heterogeneity in Systemic Lupus Erythematosus for New Therapies

Systemic lupus erythematosus (SLE) is a multisystem, chronic autoimmune disease where treatment varies by patient and disease activity. Strong preclinical results and clinical correlates have motivated development of many drugs, but many of these have failed to achieve efficacy in clinical trials. FDA approval of belimumab in 2011 was the first successful SLE drug in nearly six decades. In this article, we review insights into the molecular and clinical heterogeneity of SLE from transcriptomics studies and detail their potential impact on drug development and clinical practices. We critically examine the pipeline of SLE drugs, including past failures and their associated lessons and current promising approaches. Finally, we identify opportunities for integrating these findings and drug development with new multidisciplinary advances to enhance future SLE treatment.

Two-Year, Randomized, Controlled Trial of Belimumab in Lupus Nephritis

BACKGROUND

In adults with active lupus nephritis, the efficacy and safety of intravenous belimumab as compared with placebo, when added to standard therapy (mycophenolate mofetil or cyclophosphamide-azathioprine), are unknown.

METHODS

In a phase 3, multinational, multicenter, randomized, double-blind, placebo-controlled, 104-week trial conducted at 107 sites in 21 countries, we assigned adults with biopsy-proven, active lupus nephritis in a 1:1 ratio to receive intravenous belimumab (at a dose of 10 mg per kilogram of body weight) or matching placebo, in addition to standard therapy. The primary end point at week 104 was a primary efficacy renal response (a ratio of urinary protein to creatinine of ≤0.7, an estimated glomerular filtration rate [eGFR] that was no worse than 20% below the value before the renal flare (pre-flare value) or ≥60 ml per minute per 1.73 m² of body-surface area, and no use of rescue therapy), and the major secondary end point was a complete renal response (a ratio of urinary protein to creatinine of <0.5, an eGFR that was no worse than 10% below the pre-flare value or ≥90 ml per minute per 1.73 m², and no use of rescue therapy). The time to a renal-related event or death was assessed.

RESULTS

A total of 448 patients underwent randomization (224 to the belimumab group and 224 to the placebo group). At week 104, significantly more patients in the belimumab group than in the placebo group had a primary efficacy renal response (43% vs. 32%; odds ratio, 1.6; 95% confidence interval [CI], 1.0 to 2.3; P = 0.03) and a complete renal response (30% vs. 20%; odds ratio, 1.7; 95% CI, 1.1 to 2.7; P = 0.02). The risk of a renal-related event or death was lower among patients who received belimumab than among those who received placebo (hazard ratio, 0.51; 95% CI, 0.34 to 0.77; P = 0.001). The safety profile of belimumab was consistent with that in previous trials.

CONCLUSIONS

In this trial involving patients with active lupus nephritis, more patients who received belimumab plus standard therapy had a primary efficacy renal response than those who received standard therapy alone. (Funded by GlaxoSmithKline; BLISS-LN ClinicalTrials.gov number, NCT01639339.).

A review of advances in the understanding of lupus nephritis pathogenesis as a basis for emerging therapies

Lupus nephritis is an important cause of both acute kidney injury and chronic kidney disease that can result in end-stage renal disease. Its pathogenic mechanisms are characterized by aberrant activation of both innate and adaptive immune responses, dysregulation of inflammatory signaling pathways, and increased cytokine production. Treatment of lupus nephritis remains a challenging issue in the management of systemic lupus erythematosus since the clinical presentation, response to treatment, and prognosis all vary considerably between patients and are influenced by ethnicity, gender, the degree of chronic kidney damage, pharmacogenomics, and non-immunological modulating factors. Elucidation of the various immunopathogenic pathways in lupus nephritis has resulted in the development of novel therapies, including biologics that target specific antigens on B lymphocytes to achieve B cell depletion, agents that modulate B cell proliferation and development, drugs that block co-stimulatory pathways, drugs that target T lymphocytes primarily, and therapies that target complement activation, signaling pathways, pro-inflammatory cytokines, and neutrophil extracellular traps. This review will discuss recent advances in the understanding of disease pathogenesis in lupus nephritis in the context of potential emerging therapies.

Long-term outcome of a randomised controlled trial comparing tacrolimus with mycophenolate mofetil as induction therapy for active lupus nephritis

OBJECTIVES

To report the 10-year outcome of lupus nephritis (LN) treated with mycophenolate mofetil (MMF) or tacrolimus (TAC) induction in a randomised controlled trial.

METHODS

Patients with active LN were treated with MMF or TAC combined with high-dose prednisolone. Responders were switched to azathioprine (AZA) at month 6. Clinical outcomes at 10 years (renal flares, renal function decline and mortality) were assessed. Factors affecting prognosis were studied by Cox regression. Urine protein-to-creatinine ratio (uPCr) and estimated glomerular filtration rate (eGFR) at different time points were evaluated for their prediction of a poor prognosis by receiver operating characteristic (ROC) analysis.

RESULTS

150 patients were studied (age 35.5±12.8 years). Complete renal response rate was similar between MMF (59%) and TAC-treated patients (62%; p=0.71). AZA maintenance was given to 79% patients. After 118.2±42 months, proteinuric and nephritic renal flares occurred in 34% and 37% of the MMF, and 53% and 30% of the TAC groups of patients, respectively (p=0.49). The cumulative incidence of a composite outcome of ↓eGFR ≥30%, chronic kidney disease stage 4/5 or death at 10 years was 33% in both groups (p=0.90). Factors independently associated with a poor renal prognosis were first-time LN (HR 0.12 (0.031 to 0.39); p=0.01), eGFR (HR 0.98 (0.96 to 0.99); p=0.008) and no response at month 6 (HR 5.18 (1.40 to 19.1); p=0.01). ROC analysis revealed an uPCr >0.75 and eGFR of <80 mL/min at month 18 best predicted a poor renal prognosis.

CONCLUSIONS

Long-term data confirmed non-inferiority of TAC to MMF as induction therapy of LN. An uPCr≤0.75 and eGFR of ≥80 mL/min at month 18 best predicted a favourable 10-year outcome and may be suitable targets for induction/consolidation therapy.

TRIAL REGISTRATION NUMBER

NCT00371319.

Deep Phenotyping of Urinary Leukocytes by Mass Cytometry Reveals a Leukocyte Signature for Early and Non-Invasive Prediction of Response to Treatment in Active Lupus Nephritis

Non-invasive biomarkers are necessary for diagnosis and monitoring disease activity in lupus nephritis (LN) to circumvent risks and limitations of renal biopsies. To identify new non-invasive cellular biomarkers in the urine sediment of LN patients, which may reflect kidney inflammation and can be used to predict treatment outcome, we performed in-depth urinary immune cell profiling by mass cytometry. We established a mass cytometric workflow to comparatively analyze the cellular composition of urine and peripheral blood (PB) in 13 patients with systemic lupus erythematosus (SLE) with active, biopsy-proven proliferative LN. Clinical and laboratory data were collected at the time of sampling and 6 months after induction of therapy in order to evaluate the clinical response of each patient. Six patients with different acute inflammatory renal diseases were included as comparison group. Leukocyte phenotypes and composition differed significantly between urine and paired PB samples. In urine, neutrophils and monocytes/macrophages were identified as the most prominent cell populations comprising together about 30%–83% of nucleated cells, while T and B lymphocytes, eosinophils, and natural killer (NK) cells were detectable at frequencies of <10% each. The majority of urinary T cells showed phenotypical characteristics of activated effector memory T cells (EM) as indicated by the co-expression of CD38 and CD69 – a phenotype that was not detectable in PB. Kidney inflammation was also reflected by tissue-imprinted macrophages, which phenotypically differed from PB monocytes by an increased expression of HLA-DR and CD11c. The presence of activated urinary T cells and macrophages could be used for differential diagnosis of proliferative LN forms and other renal pathologies. Most interestingly, the amount of EM in the urine sediment could be used as a biomarker to stratify LN patients in terms of response to induction therapy. Deep immunophenotypic profiling of urinary cells in LN allowed us to identify a signature of activated T cells and macrophages, which appear to reflect leukocytic infiltrates in the kidney. This explorative study has not only confirmed but also extended the knowledge about urinary cells as a future non-invasive biomarker platform for diagnosis and precision medicine in inflammatory renal diseases.

Abatacept treatment for patients with early active primary Sjögren's syndrome: a single-centre, randomised, double-blind, placebo-controlled, phase 3 trial (ASAP-III study)

BACKGROUND

Several small open-label studies have suggested efficacy of abatacept-a co-stimulation inhibitor-in patients with primary Sjögren's syndrome. These promising results warranted further evaluation. We therefore aimed to further assess the safety and efficacy of abatacept compared with placebo in patients with primary Sjögren's syndrome.

METHODS

We did a single-centre, randomised, double-blind, placebo-controlled, phase 3 trial at the University Medical Center Groningen (Groningen, Netherlands). We included patients with primary Sjögren's syndrome fulfilling the American-European Consensus Group criteria, aged 18 years or older, with positive salivary gland biopsies, time from diagnosis of 7 years or less, and a European League Against Rheumatism Sjögren's Syndrome Disease Activity Index (ESSDAI) score of 5 or more. Independent pharmacists randomly allocated patients (1:1) to either the abatacept group or placebo group using a computer-generated sequence stratified by previous use of disease-modifying anti-rheumatic drugs. Patients received at-home subcutaneous injections of abatacept (125 mg) or placebo once a week for 24 weeks. The primary outcome was the between-group difference in ESSDAI score at week 24. Efficacy was analysed in patients who received at least one drug dose and for whom post-baseline data were collected. Safety was analysed in all patients who received at least one drug dose.

FINDINGS

Between Aug 14, 2014, and Aug 23, 2018, 580 patients were reviewed for eligibility, of which 80 patients were randomly assigned to receive study treatment. Efficacy was analysed in 40 patients receiving abatacept and 39 patients receiving placebo (one patient in this group was lost to follow-up). The primary outcome did not significantly differ between the treatment groups. The adjusted mean difference in ESSDAI score at week 24 between the abatacept group and placebo group was -1·3 (95% CI -4·1 to 1·6). No deaths or treatment-related serious adverse events occurred. In 38 (95%) of 40 patients in the abatacept group, 103 adverse events occurred, including one serious adverse event and 46 infections. In 38 (95%) of 40 patients in the placebo group, 87 adverse events occurred, including four serious adverse events and 49 infections.

INTERPRETATION

On the basis of this trial, we cannot recommend abatacept treatment as standard of care to reduce systemic disease activity in patients with primary Sjögren's syndrome. Further studies should evaluate whether patients with specific clinical manifestations and biological characteristics might benefit from abatacept treatment.

FUNDING

Bristol-Myers Squibb.

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

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

Inflammatory markers in systemic lupus erythematosus

While systemic lupus erythematosus (SLE) is an autoantibody and immune complex disease by nature, most of its organ manifestations are in fact inflammatory. SLE activity scores thus heavily rely on assessing inflammation in the various organs. This focus on clinical items demonstrates that routine laboratory markers of inflammation are still limited in their impact. The erythrocyte sedimentation rate (ESR) is used, but represents a rather crude overall measure. Anemia and diminished serum albumin play a role in estimating inflammatory activity, but both are reflecting more than one mechanism, and the association with inflammation is complex. C-reactive protein (CRP) is a better marker for infections than for SLE activity, where there is only a limited association, and procalcitonin (PCT) is also mainly used for detecting severe bacterial infection. Of the cytokines directly induced by immune complexes, type I interferons, interleukin-18 (IL-18) and tumor necrosis factor (TNF) are correlated with inflammatory disease activity. Still, precise and timely measurement is an issue, which is why they are not currently used for routine purposes. While somewhat more robust in the assays, IL-18 binding protein (IL-18BP) and soluble TNF-receptor 2 (TNF-R2), which are related to the respective cytokines, have not yet made it into clinical routine. The same is true for several chemokines that are increased with activity and relatively easy to measure, but still experimental parameters. In the urine, proteinuria leads and is essential for assessing kidney involvement, but may also result from damage. Similar to the situation in serum and plasma, several cytokines and chemokines perform reasonably well in scientific studies, but are not routine parameters. Cellular elements in the urine are more difficult to assess in the routine laboratory, where sufficient routine is not always available. Therefore, the analysis of urinary T cells may have potential for better monitoring renal inflammation.

Moving Forward With Biologics in Lupus Nephritis

The majority of patients with systemic lupus erythematosus develop lupus nephritis (LN) which significantly contributes to increased risks of hospitalizations, ESRD, and death. Unfortunately, treatments for LN have not changed over the past 15 years. Despite continued efforts to elucidate the pathogenesis of LN, no new drugs have yet replaced the standard-of-care regimens of cyclophosphamide or mycophenolate mofetil plus high-dose corticosteroids. The significant limitations of standard-of-care are low complete response rates, risk of flares, and ongoing inflammation in the kidney leading to progressive renal dysfunction. Repeat and prolonged treatments are often needed to control disease, leading to a high level of severe side effects. The development of targeted drugs with better efficacy and safety are desperately needed. The rationale for targeting key immunologic pathways in LN continues to be strongly supported by basic and translational research and has generated the hope and excitement of testing these therapies in human LN. This review provides an overview of biologics studied to date in clinical trials of LN, discusses the potential reasons for their failure, and addresses the challenges moving forward.

Corticosteroids combined with doublet or single-agent immunosuppressive therapy for active proliferative lupus nephritis

OBJECTIVES

We performed a meta-analysis to assess whether corticosteroids (C) plus (+) doublet immunosuppressive therapy (IT) is superior to the classical combination of C with single-agent IT in active proliferative lupus nephritis (LN).

METHOD

Randomized trials evaluating the benefits and risks of C+doublet versus single-agent IT in active proliferative LN were obtained by searching PubMed, EMBASE, and Cochrane Central Register. The primary outcome was overall response rate (ORR). The secondary outcomes were the change from baseline in Systemic Lupus Erythematosus Disease Activity Index (SLE-DAI) score, negative conversion ratio of anti-double-stranded DNA (anti-dsDNA), and adverse events. The PROSPERO registry number is CRD42017068491.

RESULTS

Eleven trials with 1855 patients were included. Compared with C+single-agent IT, C+doublet IT had a significantly higher ORR (relative risk [RR], 1.22; 95% confidence interval [CI], 1.09 to 1.35; P < 0.01). In a subgroup analysis, C+doublet IT without biologics had a significantly higher ORR than C+single-agent IT (RR, 1.30; 95% CI, 1.13 to 1.50; P < 0.01), while C+doublet IT including biologics improved ORR only for refractory severe LN (RR, 1.46; 95% CI, 1.09 to 1.96; P = 0.012). A larger change from baseline in SLE-DAI scores (standardized mean difference, - 0.49; 95% CI, - 0.68 to - 0.30; P < 0.01) and a higher negative conversion ratio of anti-dsDNA (RR, 1.34; 95% CI, 1.06 to 1.69; P = 0.014) were observed with C+doublet IT than with C+single-agent IT. The rates of adverse events were similar between the two regimens.

CONCLUSIONS

Compared with single-agent IT, the combination of C and doublet IT without biologics improved clinical outcomes in active proliferative LN. Key Points • Compared with corticosteroids + single-agent immunosuppressive therapy, corticosteroids + doublet immunosuppressive therapy without biologics had a significantly higher overall response rate in active proliferative lupus nephritis. • Compared with corticosteroids + single-agent immunosuppressive therapy, corticosteroids + doublet immunosuppressive therapy including biologics improved overall response rate only for refractory severe lupus nephritis. • A larger change from baseline in SLE-DAI scores and a higher negative conversion ratio of anti-dsDNA were observed with corticosteroids + doublet immunosuppressive therapy than with corticosteroids + single-agent immunosuppressive therapy.

Establishing Surrogate Kidney End Points for Lupus Nephritis Clinical Trials: Development and Validation of a Novel Approach to Predict Future Kidney Outcomes

OBJECTIVE

End points currently used in lupus nephritis (LN) clinical trials lack uniformity and questionably reflect long-term kidney survival. This study was undertaken to identify short-term end points that predict long-term kidney outcomes for use in clinical trials.

METHODS

A database of 944 patients with LN was assembled from 3 clinical trials and 12 longitudinal cohorts. Variables from the first 12 months of treatment after diagnosis of active LN (prediction period) were assessed as potential predictors of long-term outcomes in a 36-month follow-up period. The long-term outcomes examined were new or progressive chronic kidney disease (CKD), severe kidney injury (SKI), and the need for permanent renal replacement therapy (RRT). To predict the risk for each outcome, hazard index tools (HITs) were derived using multivariable analysis with Cox proportional hazards regression.

RESULTS

Among 550 eligible subjects, 54 CKD, 55 SKI, and 22 RRT events occurred. Variables in the final CKD HIT were prediction-period CKD status, 12-month proteinuria, and 12-month serum creatinine level. The SKI HIT variables included prediction-period CKD status, International Society of Nephrology (ISN)/Renal Pathology Society (RPS) class, 12-month proteinuria, 12-month serum creatinine level, race, and an interaction between ISN/RPS class and 12-month proteinuria. The RRT HIT included age at diagnosis, 12-month proteinuria, and 12-month serum creatinine level. Each HIT validated well internally (c-indices 0.84-0.92) and in an independent LN cohort (c-indices 0.89-0.92).

CONCLUSION

HITs, derived from short-term kidney responses to treatment, correlate with long-term kidney outcomes, and now must be validated as surrogate end points for LN clinical trials.

Current challenges in the development of new treatments for lupus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with a considerable impact on patients' quality of life. Despite the plethora of clinical trials for SLE since the turn of the millennium, only one new treatment has been approved for the condition, and the overall pace of successful drug development remains slow. Nevertheless, the myriad of clinical studies has yielded insights that have informed and refined our understanding of eligibility criteria, outcome measures and trial design in SLE. In this review, we highlight the achievements of clinical trials as well as the major pitfalls that have been identified in drug development for SLE and, in doing so, identify areas where collaboration and consensus will be important to facilitate progress.

Update on the epidemiology, risk factors, and disease outcomes of systemic lupus erythematosus

Obtaining an updated view of the epidemiology, risk factors, and prognosis of systemic lupus erythematosus (SLE) is pivotal to our understanding of the disease burden. Recent community-based studies with comprehensive methodology provided more accurate disease occurrence estimates and suggested that SLE may be more frequent than previously thought. Gender, race, and socioeconomic status are important disease determinants, and there is increasing appreciation of the contribution of family history and environmental exposures in SLE susceptibility. Owing to its systemic nature, assessment of disease activity is challenging, also pertaining to efforts to improve trial endpoints for better discrimination between active drug and placebo. Notably, emerging evidence supports that remission or low disease activity states and prevention of flares are realistic targets in the management of SLE associated with improved prognosis. For the future, we anticipate that high-throughput analyses in patient cohorts will enhance the identification of robust biomarkers for diagnosis, risk stratification, and personalized treatment.

Lessons learned from the failure of several recent trials with biologic treatment in systemic lupus erythematosus

INTRODUCTION

Treatment of systemic lupus erythematosus (SLE) represents a challenge due to variable disease manifestations, clinical course, and outcome. Long-term outcome in SLE remain unsatisfactory and a search for new therapeutic options is definitely warranted. Despite expectations, most clinical trials performed in SLE and lupus nephritis in the last decade did not reach primary outcome, and the only drug that has been licensed is belimumab.

AREAS COVERED

Results of negative trials testing monoclonal antibodies and other biologic agents in SLE are briefly summarized. Reasons for the failure of the trials are listed and discussed.

EXPERT OPINION

Future studies should recruit patients with similar organ involvement, better defined disease manifestations, higher activity, and similar severity. In addition to testing higher efficacy if given as add-on treatment to standard-of-care, the trials should be aimed at reducing dosing, or completely eliminating some parts of the current standard treatment, especially corticosteroids. Median follow-up of the patients should be longer. Moreover, specific biomarkers are needed to help to identify eligible patients and to better define response to treatment. An urgent unmet need is testing these new drugs in patients with severe SLE (including those refractory to current treatment).

Immunosuppressive treatment for proliferative lupus nephritis

BACKGROUND

Cyclophosphamide, in combination with corticosteroids, has been first-line treatment for inducing disease remission for proliferative lupus nephritis, reducing death at five years from over 50% in the 1950s and 1960s to less than 10% in recent years. Several treatment strategies designed to improve remission rates and minimise toxicity have become available. Treatments, including mycophenolate mofetil (MMF) and calcineurin inhibitors, alone and in combination, may have equivalent or improved rates of remission, lower toxicity (less alopecia and ovarian failure) and uncertain effects on death, end-stage kidney disease (ESKD) and infection. This is an update of a Cochrane review first published in 2004 and updated in 2012.

OBJECTIVES

Our objective was to assess the evidence and evaluate the benefits and harms of different immunosuppressive treatments in people with biopsy-proven lupus nephritis. The following questions relating to management of proliferative lupus nephritis were addressed: 1) Are new immunosuppressive agents superior to or as effective as cyclophosphamide plus corticosteroids? 2) Which agents, dosages, routes of administration and duration of therapy should be used? 3) Which toxicities occur with the different treatment regimens?

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Specialised Register up to 2 March 2018 with support from the Cochrane Information Specialist using search terms relevant to this review. Studies in the Specialised Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs comparing any immunosuppressive treatment for biopsy-proven class III, IV, V+III and V+VI lupus nephritis in adult or paediatric patients were included.

DATA COLLECTION AND ANALYSIS

Data were abstracted and the risks of bias were assessed independently by two authors. Dichotomous outcomes were calculated as risk ratio (RR) and measures on continuous scales calculated as mean differences (MD) with 95% confidence intervals (CI). The primary outcomes were death (all causes) and complete disease remission for induction therapy and disease relapse for maintenance therapy. Evidence certainty was determined using GRADE.

MAIN RESULTS

In this review update, 26 new studies were identified, to include 74 studies involving 5175 participants overall. Twenty-nine studies included children under the age of 18 years with lupus nephritis, however only two studies exclusively examined the treatment of lupus nephritis in patients less than 18 years of age.Induction therapy Sixty-seven studies (4791 participants; median 12 months duration (range 2.5 to 48 months)) reported induction therapy. The effects of all treatment strategies on death (all causes) and ESKD were uncertain (very low certainty evidence) as this outcome occurred very infrequently. Compared with intravenous (IV) cyclophosphamide, MMF may have increased complete disease remission (RR 1.17, 95% CI 0.97 to 1.42; low certainty evidence), although the range of effects includes the possibility of little or no difference.Compared to IV cyclophosphamide, MMF is probably associated with decreased alopecia (RR 0.29, 95% CI 0.19 to 0.46; 170 less (129 less to 194 less) per 1000 people) (moderate certainty evidence), increased diarrhoea (RR 2.42, 95% CI 1.64 to 3.58; 142 more (64 more to 257 more) per 1000 people) (moderate certainty evidence) and may have made little or no difference to major infection (RR 1.02, 95% CI 0.67 to 1.54; 2 less (38 less to 62 more) per 1000 people) (low certainty evidence). It is uncertain if MMF decreased ovarian failure compared to IV cyclophosphamide because the certainty of the evidence was very low (RR 0.36, 95% CI 0.06 to 2.18; 26 less (39 less to 49 more) per 1000 people). Studies were not generally designed to measure ESKD.MMF combined with tacrolimus may have increased complete disease remission (RR 2.38, 95% CI 1.07 to 5.30; 336 more (17 to 1048 more) per 1000 people (low certainty evidence) compared with IV cyclophosphamide, however the effects on alopecia, diarrhoea, ovarian failure, and major infection remain uncertain. Compared to standard of care, the effects of biologics on most outcomes were uncertain because of low to very low certainty of evidence.Maintenance therapyNine studies (767 participants; median 30 months duration (range 6 to 63 months)) reported maintenance therapy. In maintenance therapy, disease relapse is probably increased with azathioprine compared with MMF (RR 1.75, 95% CI 1.20 to 2.55; 114 more (30 to 236 more) per 1000 people (moderate certainty evidence). Multiple other interventions were compared as maintenance therapy, but patient-outcome data were sparse leading to imprecise estimates.

AUTHORS' CONCLUSIONS

In this review update, studies assessing treatment for proliferative lupus nephritis were not designed to assess death (all causes) or ESKD. MMF may lead to increased complete disease remission compared with IV cyclophosphamide, with an acceptable adverse event profile, although evidence certainty was low and included the possibility of no difference. Calcineurin combined with lower dose MMF may improve induction of disease remission compared with IV cyclophosphamide, but the comparative safety profile of these therapies is uncertain. Azathioprine may increase disease relapse as maintenance therapy compared with MMF.

Clinical Outcomes Observed among Biopsy Proven Lupus Nephritis Patients Treated with Mycophenolate Mofetil as First-line Therapy

Background and objective The rate of end-stage renal disease from lupus nephritis has not declined, in spite of recent advances in therapeutics, such as mycophenolate mofetil (MMF). To provide insight into rates of the clinical outcomes in current practice after biopsy-proven lupus nephritis, we used a prospective cohort of the patients with newly diagnosed lupus nephritis, treated with MMF and observed their outcomes. Method Twenty systemic lupus erythematosus (SLE) patients who began mycophenolate mofetil shortly after a biopsy-confirmed diagnosis of lupus nephritis were included in the analysis. There were five patients with class III, nine with class IV, four with class III-V, one with class IV-V and two with class V lupus nephritis. The initial dose of mycophenolate mofetil was 1000 mg twice daily. If no improvement was observed, the dose was increased to 1500 mg twice daily after one month. We estimated the survival function for the time until the urine protein/creatinine reached 0.50 grams or less, after starting MMF by using an approach that accommodated interval-censored data. We also evaluated the treatment response using five different sets of criteria for the response that have previously been used in the clinical trials. These included the Bristol Myers-Squibb (BMS), the American College of Rheumatology (ACR), the lupus nephritis assessment with rituximab (LUNAR ), the Aspreva Lupus Management Study (ALMS), and the Abatacept and Cyclophosphamide Combination Efficacy and Safety Study (ACCESS). Result We estimated that 52% of the SLE patients reached 0.50 grams of proteinuria within 51 days of starting mycophenolate mofetil (95% confidence interval 29%-74%) and 77% reached 0.50 grams or less within 260 days (95% confidence interval 57%-97%). The probability of response at 90 and 180 days was 5% and 33% (the Bristol Myers-Squibb), 26% and 57% (the American College of Rheumatology), and 11% and 28% (the lupus nephritis assessment with rituximab, the Aspreva Lupus Management Study and the Abatacept and Cyclophosphamide Combination Efficacy and Safety Study). Conclusion The complete renal response ranged from 28% to 57% at six months in the routine clinical practice, mirroring the results in randomized clinical trials. Regardless of the response measures, the complete renal response was slow and, by most indices, reached in only a minority of the patients by the end of six months of the induction therapy. This indicates the urgent need for the faster and more effective lupus nephritis treatments.

[Lupus nephropathy: Insight in new treatments]

Systemic lupus erythematosus is a chronic autoimmune disease. Both acquired and innate immune systems are involved in the development of this systemic disease. Lupus nephritis usually is the most serious manifestation of systemic lupus erythematosus, with significant morbidity and mortality. The physiopathological development of the renal involvement of lupus has been increasingly elucidated over the years and various target therapies have recently been developed. After some physiopathological reminders, we discuss the conventional treatment of lupus nephritis as well as the various therapeutic advances, in particular the contribution and the place of the new target therapies in the treatment of the lupus nephritis.

Update on Biologic Therapies for Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a chronic multisystemic autoimmune disease driven by genetic, hormonal, and environmental factors. Despite the advances in diagnostic and therapeutic approaches in the last decades, SLE still leads to significant morbidity and increased mortality. Although a cure for SLE is still unknown, treatment is required to control acute disease exacerbation episodes (flares), decrease the frequency and severity of subsequent lupus flares, address comorbidities, and prevent end-organ damage. While conventional SLE pharmacotherapy may exhibit suboptimal efficacy and substantial toxicity, a growing knowledge of the disease pathogenesis enabled the research on novel therapeutic agents directed at specific disease-related targets. In this paper, we review the recent progress in the clinical investigation of biologic agents targeting B cells, T cells, cytokines, innate immunity, and other immunologic or inflammatory pathways. Although many investigational agents exhibited insufficient efficacy or inadequate safety in clinical trials, one of them, belimumab, fulfilled the efficacy and safety regulatory requirements and was approved for the treatment of SLE in Europe and the USA, which confirms that, despite all difficulties, advances in this field are possible.

The new targeted therapy in systemic lupus erythematosus: Is the glass half-full or half-empty?

Biologic therapy is still limited in lupus, where chronic steroid exposure and wide-spectrum immunosuppression are major triggers of organ damage. In this viewpoint, the authors summarize their views for a "half-full or half-empty" glass on targeted therapy in SLE. The are several reasons for seeing the glass half-empty and in this section the authors propose a critical reflection on scarceness of novel targeted lupus therapies. They show how hard it is to identify suitable biological and clinical targets and to choose the patients that may best fit those targets, as well as to stratify patients according to disease subtype and response, all contributing to the final outcome. On the other hand, reasons are emerging to see the glass half-full, including the growing evidence that disease activity and damage can both be hindered by the proper use of novel drugs and that promising molecules are upcoming. In this section, the authors contextualize potentials and failures of new drugs, providing a critical reading of disappointing results and underlining the concrete benefits obtainable through a wise use of available treatments. Indeed, combining medications with new therapeutic strategies such as the treat-to-target seems the right approach to add some water to a filling glass.

Predictors of Good Long-Term Renal Outcomes in Lupus Nephritis: Results from a Single Lupus Cohort

This study aims to elucidate the predictive capabilities of proteinuria, serum creatinine (Cr), and urine RBCs (uRBCs) with respect to long-term renal outcomes in lupus nephritis (LN) in patients followed in clinic. Methods. A retrospective analysis was performed on patients with LN. We evaluated the ability of proteinuria, serum Cr, and uRBCs at 12 months to predict good long-term renal outcomes defined as serum Cr ≤ 100 mmol/L and kidney transplant/dialysis-free at the 7th year. Receiver operator characteristic curves were generated for proteinuria, serum Cr, and uRBCs to study their ability to predict good long-term outcomes and to identify their best cut-off. Descriptive statistics studied the pattern of change of proteinuria and serum Cr. Results. Proteinuria of 0.6 g/d and Cr of 83 mmol/L performed independently moderately well in predicting good long-term renal outcomes while uRBC was less accurate. Combining serum Cr to proteinuria gave a small increase in positive predictive value with a trade-off in sensitivity. Proteinuria changed within the first year whereas serum Cr changed until the 7th year. Conclusions. Both proteinuria and Cr predict good long-term renal outcomes in LN. Proteinuria's ability to change faster at 12 months makes it a favorable endpoint for clinical trials and research studies.

Update on clinical trials in systemic lupus erythematosus

PURPOSE OF REVIEW

With advancement in our understanding of pathogenic mechanisms in systemic lupus erythematosus (SLE), there is tremendous enthusiasm in examining drugs, old and new, to improve outcomes. This review highlights recent trials' successes and impasses that have come to fore.

RECENT FINDINGS

Among B-cell therapies, belimumab continues its run of successes with sustained safety and tolerability documented in a long-term extension as well as the likely approval of a subcutaneous formulation in the near future. With greater antibody-dependent cytotoxicity and less immunogenicity, there is hope for obinituzumab to succeed where its anti-CD 20 predecessors have failed. Drugs targeting type I interferons - sifalimumab and anifrolumab - have been efficacious albeit with an increase in incidence of Herpes zoster infections. There is also renewed interest in evaluating the efficacy of calcineurin inhibitors, specifically tacrolimus in the induction and maintenance of lupus nephritis. Introspection into clinical trial designs have highlighted the effects of entry criteria, end points, background medications and geographical differences on study outcomes.

SUMMARY

There are at least 50 drugs and targets being evaluated in SLE. In addition to developing new drugs to treat lupus, future trials have to focus on more effective study designs to improve chances of trial success.

Treatment of lupus nephritis: current paradigms and emerging strategies

PURPOSE OF REVIEW

Lupus nephritis is the most common organ-threatening manifestation of lupus and continues to result in end-stage renal disease. This review describes the contemporary treatment of lupus nephritis as well as emerging therapeutic strategies.

RECENT FINDINGS

Lupus nephritis management consists of an initial (induction) phase and a maintenance (extended) phase in which steroids are used in combination with another immunosuppressive medication. Current treatments are incompletely effective and associated with substantial toxicity. Despite disappointing results of several recent trials, novel therapies targeting diverse immunologic pathways are being actively studied in lupus nephritis. Two promising strategies include the use of B-cell depletion therapy and multitarget therapy with calcineurin inhibitors. In parallel with the conduct of these trials, there are ongoing efforts to improve trial design. Two recent studies of outcome measures reported that a level of proteinuria of less than 0.7-0.8 g at 12 months is most predictive of good long-term renal outcome, and that the inclusion of urine red blood cells worsens the predictive value of proteinuria alone.

SUMMARY

Improved understanding of lupus nephritis pathogenesis, development of novel therapies, and optimization of clinical trial design are leading the path forward for successful drug development in lupus nephritis. The ultimate goal of these efforts is to treat our patients in a more strategic, personalized manner that improves long-term outcomes.

Recent advances in the understanding of renal inflammation and fibrosis in lupus nephritis

Lupus nephritis is a potentially reversible cause of severe acute kidney injury and is an important cause of end-stage renal failure in Asians and patients of African or Hispanic descent. It is characterized by aberrant exaggerated innate and adaptive immune responses, autoantibody production and their deposition in the kidney parenchyma, triggering complement activation, activation and proliferation of resident renal cells, and expression of pro-inflammatory and chemotactic molecules leading to the influx of inflammatory cells, all of which culminate in destruction of normal nephrons and their replacement by fibrous tissue. Anti-double-stranded DNA (anti-dsDNA) antibody level correlates with disease activity in most patients. There is evidence that apart from mediating pathogenic processes through the formation of immune complexes, pathogenic anti-dsDNA antibodies can bind to resident renal cells and induce downstream pro-apoptotic, pro-inflammatory, or pro-fibrotic processes or a combination of these. Recent data also highlight the critical role of macrophages in acute and chronic kidney injury. Though clinically effective, current treatments for lupus nephritis encompass non-specific immunosuppression and the anti-inflammatory action of high-dose corticosteroids. The clinical and histological impact of novel biologics targeting pro-inflammatory molecules remains to be investigated. Insight into the underlying mechanisms that induce inflammatory and fibrotic processes in the kidney of lupus nephritis could present opportunities for more specific novel treatment options to improve clinical outcomes while minimizing off-target untoward effects. This review discusses recent advances in the understanding of pathogenic mechanisms leading to inflammation and fibrosis of the kidney in lupus nephritis in the context of established standard-of-care and emerging therapies.

Why targeted therapies are necessary for systemic lupus erythematosus

Systemic lupus erythematosus (SLE) continues to have important morbidity and accelerated mortality despite therapeutic advances. Targeted therapies offer the possibility of improved efficacy with fewer side effects. Current management strategies rely heavily on nonspecific immunosuppressive agents. Prednisone, in particular, is responsible for a considerable burden of later organ damage. There are a multitude of diverse mechanisms of disease activity, immunogenic abnormalities and clinical manifestations to take into consideration in SLE. Many targeted agents with robust mechanistic preclinical data and promising early phase studies have ultimately been disappointing in phase III, randomized, controlled studies. Recent efforts have focused on B-cell therapies, in particular given the success of belimumab in clinical trials, with limited success. We remain optimistic regarding other specific therapies being evaluated, including interferon-alpha blockade. It is likely that in SLE, given the heterogeneity of the population involved, precision medicine is needed, rather than expecting that any single biologic will be universally effective.

T-cell-directed therapies in systemic lupus erythematosus

Drug development for the treatment of systemic lupus erythematosus (SLE) has largely focused on B-cell therapies. A greater understanding of the immunopathogenesis of SLE coupled with advanced bioengineering has allowed for clinical trials centered on other targets for SLE therapy. The authors discuss the benefits and shortcomings of focusing on T-cell-directed therapies in SLE and lupus nephritis clinical trials.

Biologic Therapies for Autoimmune and Connective Tissue Diseases

Biologic therapy continues to revolutionize the treatment of autoimmune disease, especially in rheumatology as the pathophysiology of both inflammation and autoimmune disease becomes better understood. These therapies are designed to dampen the response of the inflammatory cascades. Although the first biologic therapies were approved many years ago, expanding indications and new agents continue to challenge the traditional treatment strategies for rheumatic diseases. This article reviews the data supporting the current use of biologic therapies, including off-label indications, in a subset of rheumatic diseases including rheumatoid arthritis, lupus, inflammatory myositis, ankylosing spondylitis, psoriatic arthritis, vasculitis, and gout.

Failure of a systemic lupus erythematosus response index developed from clinical trial data: lessons examined and learned

Background Our primary goal was to create an outcome change score index similar to a standard rheumatoid arthritis (RA) model utilizing real-world data in systemic lupus erythematosus (SLE) patients that occurred during their phase 3 trials with a Food and Drug Administration-approved drug. Methods We utilized raw data from trials of belimumab for the treatment of SLE. Data were split 80/20 into training/validation sets. Index variables present in a majority of patients and with face validity were selected. Variables were scored for each patient as percentage improvement from baseline after one year. The percentage of placebo- and drug-treated patients considered improved after the application of various criteria was ascertained. Logistic regression was employed to determine the ability of the new index to predict treatment assignment. Results A total of 1693 subjects had data for analyses. Eight variables were chosen: arthritis, rash, physician global assessment, fatigue, anti-double stranded DNA antibodies, C3, C4 and C-reactive protein. In the training dataset, ≥20% improvement in ≥4 of eight variables produced the largest difference between placebo- and drug-treated patients (22.1%) with an acceptable rate of improved placebo-treated patients (25%). This resulted in an odds ratio for belimumab (10 mg/kg) vs placebo of 2.7 (95% CI: 2.0-3.6; p < 0.001). However, in the validate dataset the odds ratio was not significant at 1.3 (95% CI: 0.8-2.2; p = 0.863). Conclusions The index created from training data did not achieve statistical significance when tested in the validation set. We have speculated why this happened. Is the lack of success of therapeutics for SLE caused by ineffective medications, study design and outcome instruments that fail to inform us, or is the heterogeneity of the disease too daunting? The lessons learned here can help direct future endeavors intended to improve SLE outcome instruments.

Lessons Learned From the Clinical Trials of Novel Biologics and Small Molecules in Lupus Nephritis

Systemic lupus erythematosus (SLE) is a ripe area for drug development. There are great unmet needs, especially for those with lupus nephritis, in which good responses occur only in the minority of treated patients. An expanded understanding of immunopathogenesis of SLE coupled with the availability of sophisticated bioengineering technologies has resulted in the ability to supply the lupus community with the reagents needed to perform clinical trials. However, drug development in SLE has proven to be particularly challenging. Only one drug, belimumab, has been approved for patients with SLE through the traditional route of randomized controlled trials. The basis for our failures is unknown, but most assuredly relates to trial design issues, confounding by background medicines, and the multiplicity of active biologic pathways in this disease. Off-label use of failed trial drugs such as mycophenolate mofetil and rituximab paradoxically has become routine in many parts of the world. Despite the obstacles, there currently is unprecedented clinical trial activity in lupus nephritis, which most likely will lead to at least one drug approval in years to come.

Immunoregulatory soluble CTLA-4 modifies effector T-cell responses in systemic lupus erythematosus

Background

The inhibitory CTLA-4 molecule is a crucial regulator of immune responses and a target for therapeutic intervention in both autoimmunity and cancer. In particular, CTLA-4 is important in controlling antigen-specific immunity, including responses to autoantigens associated with autoimmune disease. Here, we investigate cytokine responses to a range of lupus-associated autoantigens and assess whether the alternatively spliced isoform of CTLA-4, soluble CTLA-4 (sCTLA-4), contributes to immune regulation of autoantigen-specific immunity in systemic lupus erythematosus (SLE).

Methods

The cell culture supernatant production of sCTLA-4 as well as the cytokines IL-10, IFN-γ, and IL-17 from peripheral blood mononuclear cells (PBMC) from lupus patients and age- and sex-matched healthy volunteer donors were measured in response to previously identified histone and small nuclear ribonucleoprotein (snRNP) autoantigen-derived peptides (H3_91-105, H4_71-93, and U170K_131-151) by ELISA. We also examined the functional contribution of sCTLA-4 to immune regulation in the context of these autoantigenic peptides following blockade of sCTLA-4 with a selective anti-sCTLA-4 monoclonal antibody, JMW-3B3.

Results

We identified responses to autoantigenic peptides, which revealed qualitative differences in cytokine (IL-10, IL-17, and IFN-γ) profiles between SLE patients and healthy donors. PBMC from healthy donors responded to each of the lupus peptides by secreting IFN-γ and IL-17, but PBMC from SLE patients produced IL-10. Although we did not observe differences in the levels of serum or PBMC culture supernatant sCTLA-4 in either cohort, blockade of sCTLA-4 in PBMC cultures responding to antigen enhanced the cytokine profiles associated with each group.

Conclusion

The results show that lupus autoantigen-derived peptides display varied immunogenicity in lupus versus healthy volunteer donors, while sCTLA-4 acts to regulate the T-cell activity independently of response profile.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-016-1075-1) contains supplementary material, which is available to authorized users.

Efficacy of abatacept in systemic lupus erythematosus: a retrospective analysis of 11 patients with refractory disease

Objective

The objective of this study was to assess the safety and efficacy of abatacept in patients with SLE refractory to conventional treatment in routine clinical practice.

Methods

This retrospective study included 11 SLE patients treated with abatacept for an active and refractory disease. The primary endpoint was the change in SLE Disease Activity Index (SLEDAI) score at six months. Response was defined as a decrease of SLEDAI ≥4 in a patient continuing abatacept.

Results

Indications of abatacept treatment were articular ( n=8), renal ( n=1) and cutaneous ( n=1) involvement and autoimmune thrombocytopenia ( n=1). Abatacept was discontinued before six months in two patients, because of adverse event ( n=1) and/or lupus flare ( n=2). The median SLEDAI decreased from 6 (2–20) to 4 (0–20) ( p=0.031). Decrease of SLEDAI ≥4 was observed in 6/11 patients (55%) and response to treatment according to the physician's judgement in 8/11 (73%) patients. Improvement of articular involvement was observed in 7/8 (87.5%) patients. Four adverse events were observed in three patients, but no severe infection occurred.

Conclusion

This study suggests some efficacy of abatacept in patients with refractory disease in routine clinical practice, particularly in the case of articular manifestations, with an acceptable safety profile. These data support conducting new controlled trials of abatacept in SLE patients.

A pathophysiology-based approach to the diagnosis and treatment of lupus nephritis

Lupus is no longer an unknown chameleon of medicine. Significant progress has been made on unraveling the pathogenesis of lupus and lupus nephritis, and how to treat the disease. Here we provide an update on the pathophysiology of lupus and its related kidney disease, consider areas of controversy in disease management, and discuss the unmet needs of lupus nephritis and how to address these needs. We focus on rethinking how innovative therapies for lupus nephritis should be evaluated and evolving strategies to more efficiently mitigate irreversible nephron loss in patients with lupus nephritis.

Success and failure of biological treatment in systemic lupus erythematosus: A critical analysis

Patients affected with systemic lupus erythematosus (SLE) still display increased mortality and decreased quality of life in respect to general population. The major determinant of poor long term prognosis is organ damage, which is predictive of more damage and death. Damage is in turn triggered by uncontrolled disease activity and especially by the long-standing corticosteroid use which often accompanies SLE patients over their disease course, owing both to the need of reaching disease remission and to the habit of keeping patients on a small steroid dose for an indefinite period of time. Hence, the need for new drugs and therapeutic strategies aiming at minimizing damage accrual through a better control of disease activity and a steroid-sparing potential is paramount. So far, however, the therapeutic strategy in SLE requires a multitarget approach which is not devoid of widespread immunesuppression. In fact, several studies have been carried out in recent years targeting both the adaptive and the innate immune system, the majority of which did not achieve their primary endpoint, being often divergent from successful clinical experience and thereby committing physician to off-label use of targeted therapies in face of refractory SLE manifestations. The study designs and the chosen endpoints were often blamed for inadequacy, being at least in part responsible for study failures. In this review, we go over major clinical trials conducted in SLE by analyzing any critical aspects related to study design, predefined endpoints and biological activity of novel compounds that may have hampered study outcome, despite the great effort of providing less toxic drugs within a targeted, pathogenic-based approach.

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.