Attainment of treat-to-target endpoints in SLE patients with high disease activity in the atacicept phase 2b ADDRESS II study

Systemic Lupus Erythematosus Disease Activity Score Remission and Low Disease Activity States Discriminate Drug From Placebo and Better Health-Related Quality of Life

OBJECTIVE

Our objective was to evaluate the ability of Systemic Lupus Erythematosus Disease Activity Score (SLE-DAS) remission and low disease activity (LDA) to discriminate active drug from placebo and to discriminate outcomes in the patients' perspective (health-related quality of life [HR-QoL]) in SLE trials.

METHODS

This was a post hoc analysis of the pooled Belimumab in Subjects With SLE (BLISS)-52 (NCT00424476) and BLISS-76 (NCT00410384) trials data. SLE-DAS remission and LDA attainment and discrimination between belimumab and placebo at 52 weeks were compared using chi-square tests. At week 52, 36-item Short Form Health Survey (SF-36) and Functional Assessment of Chronic Illness Therapy Fatigue (FACIT-F) scores were compared between patients attaining SLE-DAS remission versus nonremission and SLE-DAS LDA versus non-LDA using the t-test and Mann-Whitney test. Mean changes from week 0 to 52 in SF-36 and FACIT-F scores were compared between groups using multivariate regression analysis adjusted for baseline scores.

RESULTS

At week 52, significantly more patients attained SLE-DAS LDA taking belimumab 1 mg/kg (17.9% vs 13.0%; P = 0.023; odds ratio [OR] 1.459; relative risk [RR] 1.377; number needed to treat [NNT] 20.4) and 10 mg/kg (21.7% vs 13.0%; P < 0.001; OR 1.853; RR 1.668; NNT 11.5) compared with placebo. Likewise, more patients attained SLE-DAS remission taking belimumab 10 mg/kg compared to placebo (14.7% vs 10.1%; P = 0.019; OR 1.532; RR 1.454; NNT 21.7). At week 52, patients attaining SLE-DAS remission and LDA presented higher SF-36 domain and summary scores (all P < 0.001) and FACIT-F scores (both P < 0.001). Mean improvements from baseline in SF-36 and FACIT-F scores were significantly higher in patients achieving SLE-DAS remission and LDA.

CONCLUSION

SLE-DAS remission and LDA showed discriminant ability for identifying patients receiving active drug in SLE clinical trials. Attainment of these SLE-DAS targets are associated with better HR-QoL.

New and emerging therapies for systemic lupus erythematosus

Systemic Lupus Erythematosus (SLE) and lupus nephritis treatment is still based on non-specific immune suppression despite the first biological therapy for the disease having been approved more than a decade ago. Intense basic and translational research has uncovered a multitude of pathways that are actively being evaluated as treatment targets in SLE and lupus nephritis, with two new medications receiving FDA approval in the last 3 years. Herein we provide an overview of targeted therapies for SLE including medications targeting the B lymphocyte compartment, intracellular signaling, co-stimulation, and finally the interferons and other cytokines.

Association of systemic lupus erythematosus standard of care immunosuppressants with glucocorticoid use and disease outcomes: a multicentre cohort study

BACKGROUND

This study examines the association of standard-of-care systemic lupus erythematosus (SLE) medications with key outcomes such as low disease activity attainment, flares, damage accrual, and steroid-sparing, for which there is current paucity of data.

METHODS

The Asia Pacific Lupus Collaboration (APLC) prospectively collects data across numerous sites regarding demographic and disease characteristics, medication use, and lupus outcomes. Using propensity score methods and panel logistic regression models, we determined the association between lupus medications and outcomes.

RESULTS

Among 1707 patients followed over 12,689 visits for a median of 2.19 years, 1332 (78.03%) patients achieved the Lupus Low Disease Activity State (LLDAS), 976 (57.18%) experienced flares, and on most visits patients were taking an anti-malarial (69.86%) or immunosuppressive drug (76.37%). Prednisolone, hydroxychloroquine and azathioprine were utilised with similar frequency across all organ domains; methotrexate for musculoskeletal activity. There were differences in medication utilisation between countries, with hydroxychloroquine less frequently, and calcineurin inhibitors more frequently, used in Japan. More patients taking leflunomide, methotrexate, chloroquine/hydroxychloroquine, azathioprine, and mycophenolate mofetil/mycophenolic acid were taking ≤ 7.5 mg/day of prednisolone (compared to > 7.5 mg/day) suggesting a steroid-sparing effect. Patients taking tacrolimus were more likely (Odds Ratio [95% Confidence Interval] 13.58 [2.23-82.78], p = 0.005) to attain LLDAS. Patients taking azathioprine (OR 0.67 [0.53-0.86], p = 0.001) and methotrexate (OR 0.68 [0.47-0.98], p = 0.038) were less likely to attain LLDAS. Patients taking mycophenolate mofetil were less likely to experience a flare (OR 0.79 [0.64-0.97], p = 0.025). None of the drugs was associated with a reduction in damage accrual.

CONCLUSIONS

This study suggests a steroid-sparing benefit for most commonly used standard of care immunosuppressants used in SLE treatment, some of which were associated with an increased likelihood of attaining LLDAS, or reduced incidence of flares. It also highlights the unmet need for effective treatments in lupus.

Targeting DORIS Remission and LLDAS in SLE: A Review

Remission is the established therapeutic goal for patients with systemic lupus erythematosus (SLE) and is currently defined by the widely adopted Definition Of Remission In SLE (DORIS) criteria. Attainment of remission is rare in the clinical setting, thus an alternative, pragmatic treatment target of low disease activity, as defined by the Lupus Low Disease Activity State (LLDAS), provides a less stringent and more attainable treatment goal for a wider proportion of patients compared with DORIS remission. Randomized controlled trials and real-world analyses have confirmed the positive clinical benefits of achieving either DORIS remission or LLDAS. The treat-to-target (T2T) approach utilizes practical clinical targets to proactively tailor individual treatment regimens. Studies in other chronic inflammatory diseases using the T2T approach demonstrated significantly improved clinical outcomes and quality-of-life measures compared with established standard of care. However, such trials have not yet been performed in patients with SLE. Here we review the evolution of DORIS remission and LLDAS definitions and the evidence supporting the positive clinical outcomes following DORIS remission or LLDAS attainment, before discussing considerations for implementation of these outcome measures as potential T2T objectives. Adoption of DORIS remission and LLDAS treatment goals may result in favorable patient outcomes compared with established standard of care for patients with SLE.

The contribution of a proliferation-inducing ligand (APRIL) and other TNF superfamily members in pathogenesis and progression of IgA nephropathy

Advances in our understanding of the pathogenesis of immunoglobulin A nephropathy (IgAN) have led to the identification of novel therapeutic targets and potential disease-specific treatments. Specifically, a proliferation-inducing ligand (APRIL) has been implicated in the pathogenesis of IgAN, mediating B-cell dysregulation and overproduction of pathogenic galactose-deficient IgA1 (Gd-IgA1). Animal and clinical studies support the involvement of APRIL in the pathogenesis and progression of IgAN. An elevated level of APRIL is found in IgAN when compared with controls, which correlates with the level of Gd-IgA1 and associates with more severe disease presentation and worse outcomes. Conversely, anti-APRIL therapy reduces pathogenic Gd-IgA1 and IgA immune complex formation and ameliorates the severity of kidney inflammation and injury. Genome-wide association studies in IgAN have identified TNFSF13 and TNFRSF13B, a cytokine ligand-receptor gene pair encoding APRIL and its receptor, respectively, as risk susceptibility loci in IgAN, further supporting the causal role of the APRIL signalling pathway in IgAN. Several novel experimental agents targeting APRIL, including atacicept, telitacicept, zigakibart and sibeprenlimab, are currently under investigation as potential therapies in IgAN. Preliminary results suggest that these agents are well-tolerated, and reduce levels of Gd-IgA1, with corresponding improvement in proteinuria. Further studies are ongoing to confirm the safety and efficacy of anti-APRIL approaches as an effective therapeutic strategy in IgAN.

Identifying lupus Patient Subsets Through Immune Cell Deconvolution of Gene Expression Data in Two Atacicept Phase II Studies

OBJECTIVE

To use cell-based gene signatures to identify patients with systemic lupus erythematous (SLE) in the phase II/III APRIL-SLE and phase IIb ADDRESS II trials most likely to respond to atacicept.

METHODS

A published immune cell deconvolution algorithm based on Affymetrix gene array data was applied to whole blood gene expression from patients entering APRIL-SLE. Five distinct patient clusters were identified. Patient characteristics, biomarkers, and clinical response to atacicept were assessed per cluster. A modified immune cell deconvolution algorithm was developed based on RNA sequencing data and applied to ADDRESS II data to identify similar patient clusters and their responses.

RESULTS

Patients in APRIL-SLE (N = 105) were segregated into the following five clusters (P1-5) characterized by dominant cell subset signatures: high neutrophils, T helper cells and natural killer (NK) cells (P1), high plasma cells and activated NK cells (P2), high B cells and neutrophils (P3), high B cells and low neutrophils (P4), or high activated dendritic cells, activated NK cells, and neutrophils (P5). Placebo- and atacicept-treated patients in clusters P2,4,5 had markedly higher British Isles Lupus Assessment Group (BILAG) A/B flare rates than those in clusters P1,3, with a greater treatment effect of atacicept on lowering flares in clusters P2,4,5. In ADDRESS II, placebo-treated patients from P2,4,5 were less likely to be SLE Responder Index (SRI)-4, SRI-6, and BILAG-Based Combined Lupus Assessment responders than those in P1,3; the response proportions again suggested lower placebo effect and a greater treatment differential for atacicept in P2,4,5.

CONCLUSION

This exploratory analysis indicates larger differences between placebo- and atacicept-treated patients with SLE in a molecularly defined patient subset.

Population pharmacokinetics of atacicept in systemic lupus erythematosus: An analysis of three clinical trials

B cell stimulating factor (BLyS) and a proliferation-inducing ligand (APRIL) are targets for novel treatments in patients with systemic lupus erythematosus (SLE). Atacicept is a recombinant, soluble fusion protein that blocks BLyS and APRIL activity. This study characterized the pharmacokinetic (PK) profile of atacicept using a population PK model and identified covariates explaining the PK variability. Total atacicept concentrations from a phase I study in healthy volunteers and two phase II studies in patients with SLE, using subcutaneous administration, were modeled using a quasi-steady-state approximation of the target-mediated drug disposition model with first-order absorption. The model included 3640 serum atacicept concentration records from 37 healthy volunteers and 503 patients with SLE and described total atacicept concentrations of the three trials, providing precise estimates of all parameters. Body weight and baseline BLyS concentration were the only statistically significant covariates, whereas no differences were found between patients and healthy volunteers. Apparent clearance and volume of the central compartment increased with body weight and initial target concentration increased with baseline BLyS. The change on atacicept exposure was moderate, with a difference in area under the curve compared with the median of 20%-32% for body weight, and 7%-18% for BLyS. Therefore, the effects of these covariates on atacicept exposure are not expected to be clinically relevant. The model described the complete total atacicept concentration-time profiles without finding any differences between healthy subjects and patients with SLE and supports the 150 mg once weekly dose for further trials.

Advances in natural products and antibody drugs for SLE: new therapeutic ideas

Systemic Lupus Erythematosus (SLE) is a chronic autoimmune systemic disease with a wide range of clinical symptoms, complex development processes, and uncertain prognosis. The clinical treatment of SLE is mainly based on hormones and immunosuppressants. Research on novel therapy strategies for SLE has flourished in recent years, especially the emergence of new targeted drugs and natural products that can modulate related symptoms. This review discusses the current experience including B-cell targeted drugs (belimumab, tabalumab, blisibimod, atacicept, rituximab, ofatumumab, ocrelizumab, obexelimab, and epratuzumab), T-cell targeted drugs (abatacept, dapirolizumab, and inhibitor of syk and CaMKIV), cytokines targeted drugs (anifrolumab and sifalimumab), and natural products (curcumin, oleuropein, punicalagin, sulforaphane, icariin, apigenin, and resveratrol). The aim of this paper is to combine the existing in vitro and in vivo models and clinical research results to summarize the efficacy and mechanism of natural drugs and targeted drugs in SLE for the reference and consideration of researchers.

Current treatment of systemic lupus erythematosus: a clinician's perspective

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease. Its variable course makes it difficult to standardize patient treatment. This article aims at a literature review on available drugs for treating SLE and on drugs that have shown therapeutic effects in this disease. The PubMed/MEDLINE electronic search engine was used to identify relevant studies. This review presents the current therapeutic options, new biological therapies, and combination therapies of biologics with standard immunosuppressive and immunomodulating drugs. We have also underlined the importance to implement the treat-to-target strategy aimed at reducing or discontinuing therapy with glucocorticosteroids (GCs). The awareness of the benefits and risks of using GCs helps in refining their dosage and thereby obtaining a better safety profile. The advent of biological targeted therapies, and more recently, low-molecular-weight compounds such as kinase inhibitors, initiated numerous clinical trials in SLE patients and led to the approval of two biological drugs, belimumab, and anifrolumab, for SLE treatment. Progress in the treatment of SLE was reflected in the 2019 and 2021 recommendations of the European Alliance of Associations for Rheumatology (EULAR). However, a mass of recent clinical research data requires continuous consolidation to optimize patient outcomes.

Lupus low disease activity state attainment in the phase 3 TULIP trials of anifrolumab in active systemic lupus erythematosus

OBJECTIVES

In patients with systemic lupus erythematosus (SLE), lupus low disease activity state (LLDAS) attainment is associated with improved outcomes. We investigated LLDAS attainment in anifrolumab-treated patients.

METHODS

We performed post hoc analysis of pooled Treatment of Uncontrolled Lupus via the Interferon Pathway (TULIP-1) (NCT02446912) and TULIP-2 (NCT02446899) anifrolumab phase 3 trial data in patients with moderate to severe SLE receiving standard therapy. LLDAS was defined as: SLE Disease Activity Index 2000 ≤4 without major organ activity, no new disease activity, Physician's Global Assessment ≤1, prednisone ≤7.5 mg/day and no non-standard immunosuppressant dosing. Time to first LLDAS attainment was compared between groups using Cox regression modelling; responses were compared using logistic regression.

RESULTS

Agnostic to treatment, 205/819 (25.0%) patients attained LLDAS at week 52; 186/205 (90.7%) were also British Isles Lupus Assessment Group-based Composite Lupus Assessment (BICLA)-responders. Among BICLA-responders at week 52, 186/318 (58.5%) attained LLDAS; 203/380 (53.4%) SLE Responder Index-4 (SRI(4)) responders attained LLDAS. Improvements from baseline in patient global assessment scores at week 52 were threefold greater in LLDAS-attainers. At week 52, 30.0% of anifrolumab-treated patients and 19.6% of placebo were in LLDAS (OR 1.8, 95% CI 1.3 to 2.5, p=0.0011). Compared with placebo, anifrolumab treatment was associated with earlier LLDAS attainment (time to first LLDAS, HR 1.76, 95% CI 1.35 to 2.30, p<0.0001), increased cumulative time in LLDAS (p<0.0001) and higher likelihood of sustained LLDAS (p<0.001). Anifrolumab treatment was also associated with higher rates of Definition of Remission in SLE remission at week 52 (15.3% vs 7.6%; OR 2.2, 95% CI 1.4 to 3.6, p=0.0013).

CONCLUSIONS

LLDAS attainment was highly associated with, but more stringent than, BICLA and SRI(4) responses. Compared with placebo, anifrolumab treatment was associated with earlier, more frequent, and more prolonged and sustained LLDAS.

TRIAL REGISTRATION NUMBERS

NCT02446912 and NCT02446899.

Precision medicine in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease that has diverse clinical manifestations, ranging from restricted cutaneous involvement to life-threatening systemic organ involvement. The heterogeneity of pathomechanisms that lead to SLE contributes to between-patient variation in clinical phenotype and treatment response. Ongoing efforts to dissect cellular and molecular heterogeneity in SLE could facilitate the future development of stratified treatment recommendations and precision medicine, which is a considerable challenge for SLE. In particular, some genes involved in the clinical heterogeneity of SLE and some phenotype-related loci (STAT4, IRF5, PDGF genes, HAS2, ITGAM and SLC5A11) have an association with clinical features of the disease. An important part is also played by epigenetic varation (in DNA methylation, histone modifications and microRNAs) that influences gene expression and affects cell function without modifying the genome sequence. Immune profiling can help to identify an individual's specific response to a therapy and can potentially predict outcomes, using techniques such as flow cytometry, mass cytometry, transcriptomics, microarray analysis and single-cell RNA sequencing. Furthermore, the identification of novel serum and urinary biomarkers would enable the stratification of patients according to predictions of long-term outcomes and assessments of potential response to therapy.

Combination strategies for lupus nephritis: facts and controversies

INTRODUCTION

There is an unmet need to improve the efficacy of therapeutic regimens in lupus nephritis (LN). Cocktail immunosuppressive therapy for the synergistic effect of individual drugs may enhance efficacy and enable dosage reduction. However, the potential increase in the risk of serious and opportunistic infections is a concern. Moreover, the timing of combination therapy, adoption of a step-up or step-down approach, and the choice of drugs is still controversial, partly related to the cost-effectiveness issue.

AREAS COVERED

Evidence of a combination of conventional, newer immunosuppressive, and biologic/targeted agents in LN.

EXPERT OPINION

Early combination of conventional regimens with anti-B cell activation factor (anti-BAFF) or calcineurin inhibitors (CNIs) enhances the therapeutic effect without increasing serious adverse events in LN. However, combining anti-CD20 and anti-BAFF biologics appears to be less promising from the results of clinical trials. Initial combination strategy may be more cost-effective for patients at risk of treatment failure and renal function deterioration. With the availability of more options, the treat-to-target approach in LN is increasingly feasible and further studies are needed to compare the step-up and step-down approaches in the treatment of LN.

Association of Modified Systemic Lupus Erythematosus Responder Index Attainment With Long-Term Clinical Outcomes: A Five-Year Prospective Study

OBJECTIVE

In trials of systemic lupus erythematosus (SLE), the SLE Responder Index (SRI) is the most commonly used primary efficacy end point but has limited validation against long-term outcomes. We aimed to investigate associations of attainment of a modified version of the SRI (mSRI) with key clinical outcomes in SLE patients with up to 5 years of follow-up.

METHODS

We used data from a large multicenter, longitudinal SLE cohort in which patients received standard of care. The first visit with active disease (defined as SLE Disease Activity Index 2000 [SLEDAI-2K] score ≥6) was designated as baseline, and mSRI attainment (defined as a reduction in SLEDAI-2K ≥4 points with no worsening in physician global assessment ≥0.3 points) was determined at annual intervals from baseline up to 5 years. Associations between mSRI attainment and outcomes including disease activity, glucocorticoid dose, flare, damage accrual, Lupus Low Disease Activity State (LLDAS), and remission were studied.

RESULTS

We included 2,060 patients, with a median baseline SLEDAI-2K score of 8. An mSRI response was attained by 56% of patients at 1 year, with similar responder rates seen at subsequent annual time points. Compared to nonresponders, mSRI responders had significantly lower disease activity and prednisolone dose and higher proportions of LLDAS and remission attainment at each year, and less damage accrual at years 2 and 3. Furthermore, mSRI responder status at 1 year predicted clinical benefit at subsequent years across most outcomes, including damage accrual (odds ratio [OR] range 0.58-0.69, P < 0.05 for damage accrual ORs at all time points).

CONCLUSION

In SLE patients with active disease receiving standard of care, mSRI attainment predicts favorable outcomes over long-term follow-up, supporting the clinical meaningfulness of SRI attainment as an SLE trial end point.

Meeting report: the ALPHA project: a stakeholder meeting on lupus clinical trial outcome measures and the patient perspective

Drug development in lupus has improved over the past 10 years but still lags behind that of other rheumatic disease areas. Assessment of prospective lupus therapies in clinical trials has proved challenging for reasons that are multifactorial including the heterogeneity of the disease, study design limitations and a lack of validated biomarkers which greatly impacts regulatory decision-making. Moreover, most composite outcome measures currently used in trials do not include patient-reported outcomes. Given these factors, the Addressing Lupus Pillars for Health Advancement Global Advisory Committee members who serve on the drug development team identified an opportunity to convene a meeting to facilitate information sharing on completed and existing outcome measure development efforts. This meeting report highlights information presented during the meeting as well as a discussion on how the lupus community may work together with regulatory agencies to simplify and standardise outcome measures to accelerate development of lupus therapeutics.

Improving measures of disease activity in systemic lupus erythematosus

INTRODUCTION

Systemic lupus erythematosus (SLE) is a multisystem disease with varied manifestations and course. Variation in presentation among patients, and within the same patient, there may be varied manifestations over time. It has been difficult to measure the extent of disease activity accurately. Several investigators and groups have developed definitions of disease activity and methods to measure it. Consequently, there are currently several instruments to measure disease activity as well as damage in patients with SLE.

AREAS COVERED

This review covers currently available evidence on measures of disease activity in SLE. It discusses potential avenues for further development of new measures and the refinement of existing tools to improve disease activity measures in research and clinical care settings.

EXPERT OPINION

Given the complexity and heterogeneity of the disease, further work and tools are needed to assess disease activity better. Organ-specific measures for cutaneous, renal, and joint manifestations are needed for a detailed assessment of disease activity in conjunction with the use of disease generic tools (e.g. SLEDAI). New tools such as the SLE Disease Activity Index-Glucocorticoid Index (SLEDAI-2 KG) incorporating glucocorticoid doses to describe disease activity, SLE-DAS and SLEDAI-2 K RI-50 to record partial improvements could also be helpful.

B cell depletion and inhibition in systemic lupus erythematosus

INTRODUCTION

Systemic lupus erythematosus (SLE) is characterized by autoantibody expression and aberrant autoreactive B cells contribute to disease progression; therefore, B cell inhibition has been an attractive target for novel therapies. However, after more than two decades of research and over 40 randomized clinical trials, only one such therapy, belimumab, has been approved for use in SLE.

AREAS COVERED

In this review, we discuss the evidence for B cell-targeted therapies in SLE and lupus nephritis. Belimumab has been successful in several large clinical trials and is approved in several countries for use in SLE and lupus nephritis. Despite a lack of supporting phase III evidence, rituximab is used off-label in SLE. Several other B cell-targeted therapies have failed to meet their end points in late-stage clinical trials. Successful phase II trials have recently been reported for obinutuzumab and telitacicept with larger confirmatory trials currently underway.

EXPERT OPINION

Refinements in pharmaceutical mechanisms of action, trial design, and patient selection have resulted in recent preliminary successes, offering renewed optimism for B-cell targeted therapeutics in SLE management.

Kinetics of free and ligand-bound atacicept in human serum

BAFF (B cell activation factor of the TNF family/B lymphocyte stimulator, BLyS) and APRIL (a proliferation-inducing ligand) are targeted by atacicept, a decoy receptor consisting of the extracellular domain of TACI (transmembrane activator and calcium-modulator and cyclophilin (CAML) interactor) fused to the Fc portion of human IgG1. The purpose of the study was to characterize free and ligand-bound atacicept in humans. Total and active atacicept in serum of healthy volunteers receiving a single dose of subcutaneous atacicept or in patients treated weekly for one year were measured by ELISA, Western blot, or cell-based assays. Pharmacokinetics of free and bound atacicept were predicted based on total atacicept ELISA results. Persistence of complexes of purified atacicept bound to recombinant ligands was also monitored in mice. Results show that unbound or active atacicept in human serum exceeded 0.1 µg/ml for one week post administration, or throughout a 1-year treatment with weekly administrations. After a single administration of atacicept, endogenous BAFF bound to atacicept was detected after 8 h then increased about 100-fold within 2 to 4 weeks. Endogenous heteromers of BAFF and APRIL bound to atacicept also accumulated, but atacicept-APRIL complexes were not detected. In mice receiving intravenous injections of purified complexes pre-formed in vitro, atacicept-BAFF persisted longer (more than a week) than atacicept-APRIL (less than a day). Thus, only biologically inactive BAFF and BAFF-APRIL heteromers accumulate on atacicept in vivo. The measure of active atacicept provides further support for the once-weekly dosing regimen implemented in the clinical development of atacicept.

Advances in lupus therapeutics: Achieving sustained control of the type I interferon pathway

Achieving sustained control of disease activity in patients with systemic lupus erythematosus has been impeded by the complexity of its immunopathogenesis as well its clinical heterogeneity. In spite of these challenges, gains in understanding disease mechanisms have identified immune targets that are currently under study in trials of candidate therapeutics. Defining the type I interferon (IFN-I) pathway and autoantibodies specific for nucleic acid binding proteins as core pathogenic mediators allows an analysis of approaches that could control production of those mediators and improve patient outcomes. This review describes therapeutic targets and agents that could achieve control of the IFN-I pathway. Toll-like receptor 7, involved in IFN-I production and differentiation of B cells, and long-lived plasma cells, the producers of autoantibodies specific for RNA-binding proteins, components of the immune complex drivers of IFN-I, are particularly attractive therapeutic targets.

Caveats and pitfalls in defining low disease activity in systemic lupus erythematosus

The treat-to-target strategy has been recently suggested in the management of Systemic Lupus Erythematosus (SLE). Lupus Low Disease Activity State (LLDAS) and Definitions Of Remission In SLE (DORIS) remission were outlined as two concentric targets. The achievement of LLDAS was shown to be associated with lower frequency of SLE flare, decreased damage progression, better quality of life, and reduced mortality. In addition, LLDAS has successfully been tested in post-hoc analyses of a number of randomized controlled trials. However, it has been recently underlined that LLDAS includes a high proportion of patients in remission, raising the question if these endpoints are sufficiently distinct to consider their separation clinically relevant. Some studies suggest that the protective effect of LLDAS on damage might be due to the inclusion of patients who are in remission. Notably, clinical low disease activity (LDA) seems to be uncommon in SLE due to the relapsing-remitting pattern of the disease, in which low level of activity only occurs transiently. Moreover, since the domains included in LLDAS have several limitations, such as the use of a binomial disease activity index, the exclusion of some mild manifestations and the consideration of items subjected to variability (physician global assessment and glucocorticoids dose), not all patients in LDA are adequately represented by LLDAS.

Randomized Phase II JANUS Study of Atacicept in Patients With Immunoglobulin A Nephropathy and Persistent Proteinuria

Introduction

Patients with IgA nephropathy (IgAN) and persistent proteinuria are at risk of progression to kidney failure. Atacicept is a novel B-cell–targeted immunomodulator, shown to reduce immunoglobulin levels in patients with autoimmune diseases.

Methods

JANUS (NCT02808429) was a phase II study that assessed the safety, pharmacodynamic effects, and efficacy of atacicept in patients with IgAN and proteinuria ≥1 g/d or 0.75 mg/mg on 24-hour UPCR despite maximal standard of care therapy.

Results

A total of 16 patients were randomized 1:1:1 to placebo (n = 5), atacicept 25 mg (n = 6), or atacicept 75 mg (n = 5) once weekly using subcutaneous injection. Twelve (75%) completed ≥48 weeks of treatment; 8 (50%) completed 72 weeks of treatment and the 24-week safety follow-up period. Fourteen patients reported treatment-emergent adverse events (TEAEs). Most TEAEs were mild or moderate in severity. Three patients (placebo n = 1; atacicept 25 mg n = 2) reported serious TEAEs, none of which were treatment related. Dose-dependent reductions in IgA, IgG, IgM, and galactose-deficient (Gd)-IgA1 with atacicept at week 24 were maintained to week 72. Early reduction in proteinuria was observed at week 24 with atacicept. Renal function progressively declined with placebo but remained stable under exposure to atacicept.

Conclusion

Atacicept has an acceptable safety profile in patients with IgAN and is effective at reducing the levels of pathogenic factor Gd-IgA1, with potential improvements in proteinuria and renal function.

Treat-to-target in systemic lupus erythematosus: advancing towards its implementation

The treat-to-target (T2T) concept has improved outcomes for patients with diabetes, hypertension and rheumatoid arthritis. This therapeutic strategy involves choosing a well-defined, relevant target, taking therapeutic steps, evaluating whether the target has been achieved, and taking action if it has not. The T2T principle has been embraced by systemic lupus erythematosus (SLE) experts, but measurable and achievable outcomes, and therapeutic options, are needed to make this approach possible in practice. Considerable evidence has been generated regarding meaningful 'state' outcomes for SLE. Low disease activity has been defined and studied, and the most aspirational goal, remission, has been defined by the Definition of Remission in SLE task force. By contrast, current therapeutic options in SLE are limited, and more effective and safer therapies are urgently needed. Fortunately, clinical trial activity in SLE has been unprecedented, and encouraging results have been seen for novel therapies, including biologic and small-molecule agents. Thus, with the expected advent of such treatments, it is likely that sufficiently diverse therapies for SLE will be available in the foreseeable future, allowing the routine implementation of T2T approaches in the care of patients with SLE.

Definition of Low Disease Activity State based on the SLE-DAS: Derivation and validation in a multicentre real-life cohort

OBJECTIVES

To derive and validate a definition of low disease activity (LDA) for systemic lupus erythematosus (SLE) based on the SLE Disease Activity Score (SLE-DAS), in a real-life multicentre cohort of SLE patients.

METHODS

Derivation was conducted using data from a monocentric cohort of SLE (Portugal), and validation was performed in a multicentre cohort (Italy, France, and Spain). The Lupus Low Disease Activity State (LLDAS) was used as comparator. We applied receiver operating characteristics (ROC) curve analysis against the LLDAS to determine the cut-off of SLE-DAS for LDA using bootstrap methodology. In a second step, we tested a definition of SLE-DAS LDA that included: (i) the statistically derived SLE-DAS upper threshold for LDA, and (ii) prednisone dose ≤7.5 mg/day. In the multicentre validation cohort, we assessed the classification performance of this SLE-DAS LDA definition.

RESULTS

We included 774 patients, 300 in the derivation and 474 in the validation cohorts, respectively. In the derivation cohort, the optimal cut-off to identify patients in LLDAS was SLE-DAS ≤2.48, presenting an area under the curve (AUC) of 0.965 (95%CI 0.935-0.994). When applied to the multicentre validation cohort, the SLE-DAS LDA definition showed a sensitivity of 97.1% and a specificity of 97.7% for LLDAS and an almost perfect agreement (Cohen's Kappa =0.933; p< 0.001). McNemar's test found no significant differences between the two definitions (p= 0.092).

CONCLUSION

The SLE-DAS LDA is a validated, accurate, and easy-to-use definition for classifying SLE patients in LDA state.

Safety and clinical activity of atacicept in the long-term extension of the phase 2b ADDRESS II study in systemic lupus erythematosus

OBJECTIVES

Atacicept reduced SLE disease activity in the phase 2b ADDRESS II study, particularly in patients with high disease activity (HDA; SLEDAI-2K ≥10) at screening. We assessed long-term safety and efficacy of atacicept in the long-term extension (LTE) of ADDRESS II.

METHODS

In the 24-week, randomized, double-blind, placebo-controlled ADDRESS II study, patients received weekly atacicept (75 or 150 mg) or placebo. Atacicept was continued at the same dose in atacicept-treated patients in the LTE; placebo-treated patients switched to atacicept 150 mg. Long-term safety was the primary endpoint. Secondary endpoints included SLE responder index (SRI)-4 and SRI-6 response rates and flares.

RESULTS

In total, 253 patients entered the ADDRESS II LTE; 88 received atacicept 150 mg, 82 atacicept 75 mg and 83 placebo/atacicept 150 mg. Median active treatment duration in the LTE was 83.8 weeks. Frequencies of treatment-emergent adverse events (TEAEs) were similar across groups (90.4-93.2%), and 12.5%, 14.6% and 21.7% of patients in the atacicept 150 mg, atacicept 75 mg and placebo/atacicept 150 mg groups reported serious TEAEs during the treatment period. The proportions of patients with TEAEs leading to discontinuation were 5.7%, 4.9% and 10.8%, respectively. SRI-4 and SRI-6 response rates were maintained with atacicept in the modified intent-to-treat and HDA populations and those on continuous 150 mg had a reduced risk of first severe flare and longer time to first severe flare vs those who initially received placebo.

CONCLUSION

Long-term treatment with atacicept 150 mg in SLE patients had an acceptable safety profile, with durable efficacy.

TRIAL REGISTRATION

ClinicalTrials.gov, http://clinicaltrials.gov, NCT02070978.

Telitacicept as a BLyS/APRIL dual inhibitor for autoimmune disease

The pathogenic roles for B cells in autoimmunity include produce pathogenic autoantibodies and modulate immune responses via the production of cytokines and chemokines. The B lymphocyte stimulator BLyS (also known as B-cell-activating factor, BAFF) and APRIL (a proliferation-inducing ligand) are critical factors in the maintenance of the B-cell pool and humoral immunity, namely BLyS modulates the differentiation and maturation of immature B cell, while APRIL modulates the function and survival of long-lived plasma cell, which plays a prominent role in the pathogenesis of autoimmune diseases. Telitacicept is a novel recombinant fusion protein of both the ligand-binding domain of the TACI receptor and the Fc component of human IgG and which is a BLyS/APRIL dual inhibitor. Moreover, telitacicept was developed by Remegen Co., Ltd. in China and is approved to treat systemic lupus erythematosus in China. We review the rationale, clinical evidence, and future perspectives of telitacicept for the treatment of autoimmune disease.HighlightThe B lymphocyte stimulator BLyS (also known as B-cell-activating factor, BAFF) and APRIL (a proliferation-inducing ligand), members of tumor necrosis factor (TNF) family, and which are critical factors in the maintenance of the B-cell pool and humoral immunity.BAFF and APRIL are implicated in the pathogenesis of several human autoimmune diseases with autoreactive B-cell involvement, and targeting both is beneficial for the treatment of autoimmune diseases.Telitacicept is a novel recombinant fusion protein of both the ligand-binding domain of the TACI receptor and the Fc component of human IgG, as a BLyS/APRIL dual inhibitor and which has been approved by National Medical Products Administration (MNPA) for the treatment of patients with SLE in China.With more clinical trials underway, telitacicept may also be approved for the treatment of other autoimmune diseases in the future.

Disease course following High Disease Activity Status revealed patterns in SLE

BACKGROUND

We sought to examine the disease course of High Disease Activity Status (HDAS) patients and their different disease patterns in a real-world longitudinal cohort. Disease resolution till Lupus Low Disease Activity State (LLDAS) has been a general treatment goal, but there is limited information on this subset of patients who achieve this.

METHODS

All consenting patients of the Monash Lupus Cohort who had at least 12 months of observation were included. HDAS was defined as SLEDAI-2K ≥ 10 ever, and HDAS episode as the period from the first HDAS clinic visit until attainment of LLDAS. We examined the associations of different HDAS patterns with the likelihood of damage accrual.

RESULTS

Of 342 SLE patients, 151 experienced HDAS at least once, accounting for 298 HDAS episodes. The majority of HDAS patients (76.2%) experienced Recurrent HDAS (> 1 HDAS visit), and a smaller subset (47.7%) had Persistent HDAS (consecutive HDAS visits for longer than 2 months). Recurrent or Persistent HDAS patients were younger at diagnosis and more likely to experience renal or serositis manifestations; persistent HDAS patients were also more likely to experience neurological manifestations. Baseline SLEDAI greater than 10 was associated with longer HDAS episodes. Recurrent and Persistent HDAS were both associated with an increased likelihood of damage accrual. The total duration of HDAS episode greater than 2 years and experiencing multiple HDAS episodes (≥4) was also associated with an increased likelihood of damage accrual (OR 1.80, 95% CI 1.08-2.97, p = 0.02, and OR 3.31, 95% CI 1.66-13.26, p = 0.01, respectively).

CONCLUSION

HDAS episodes have a highly variable course. Recurrent and Persistent HDAS, and longer duration of HDAS episodes, increased the risk of damage accrual. In addition to a major signifier of severity in SLE, its resolution to LLDAS can determine the subsequent outcome in SLE patients.

Updates on Clinical Trials in Systemic Lupus Erythematosus

PURPOSE OF REVIEW

Because of the complexity of systemic lupus erythematosus (SLE), different approaches are undertaken while investigating potential therapeutic compounds to treat the disease. The purpose of this review is to summarize the results from recent clinical trials, which investigated different compounds for treating SLE.

RECENT FINDINGS

Targeting B cells and type I interferons constitutes the major focus in recent clinical trials. The potential for therapeutic effects of small molecule inhibition such as JAK, Tyk, and Btk is now being investigated for treating SLE. The immunoregulation of T cell activation in SLE is studied using low-dose IL-2 and CD40 ligand inhibition. There are clinical trials that study bispecific antibodies, with binding specificities for 2 different target molecules related to T- and B-cell activation or to different aspects of B cell activation. An approach of combination treatment is also being studied. Clinical trials are underway and new treatment compounds for SLE are being anticipated.

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.

Immunological memory in rheumatic inflammation - a roadblock to tolerance induction

Why do we still have no cure for chronic inflammatory diseases? One reason could be that current therapies are based on the assumption that chronic inflammation is driven by persistent 'acute' immune reactions. Here we discuss a paradigm shift by suggesting that beyond these reactions, chronic inflammation is driven by imprinted, pathogenic 'memory' cells of the immune system. This rationale is based on the observation that in patients with chronic inflammatory rheumatic diseases refractory to conventional immunosuppressive therapies, therapy-free remission can be achieved by resetting the immune system; that is, by ablating immune cells and regenerating the immune system from stem cells. The success of this approach identifies antigen-experienced and imprinted immune cells as essential and sufficient drivers of inflammation. The 'dark side' of immunological memory primarily involves memory plasma cells secreting pathogenic antibodies and memory T lymphocytes secreting pathogenic cytokines and chemokines, but can also involve cells of innate immunity. New therapeutic strategies should address the persistence of these memory cells. Selective targeting of pathogenic immune memory cells could be based on their specificity, which is challenging, or on their lifestyle, which differs from that of protective immune memory cells, in particular for pathogenic T lymphocytes. The adaptations of such pathogenic memory cells to chronic inflammation offers entirely new therapeutic options for their selective ablation and the regeneration of immunological tolerance.

Emerging B-Cell Therapies in Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a chronic, multisystem, autoimmune disease of unknown etiology, whose hallmark is the production of autoantibodies. B cells are promising targets for novel SLE therapies. In 2011, belimumab (Benlysta®), a fully humanized monoclonal antibody inhibiting B-cell activation and proliferation, was the first medication in 50 years to be approved by the US Food and Drug Administration to treat adult SLE. This review discusses the current experience with B-cell-targeted therapies, including those targeting B-cell-surface antigens (rituximab, ocrelizumab, ofatumumab, obinutuzumab, obexelimab, epratuzumab, daratumumab), B-cell survival factors (belimumab, tabalumab, atacicept, blisibimod), or B-cell intracellular functions (ibrutinib, fenebrutinib, proteasome inhibitors), for the management of SLE. It focuses on ongoing clinical trials and real-world post-marketing use, where available, including their safety profiles, and concludes with our recommendations for B-cell-centric approaches to the management of SLE.

Which is the best SLE activity index for clinical trials?

Following the advent of molecular targeted drugs, a paradigm shift in treatment similar to that in rheumatoid arthritis has been expected in the treatment of systemic lupus erythematosus (SLE), but clinical trials for drugs that many specialists believed to be effective have failed repeatedly. The causes are not simple, but include the heterogeneity of SLE, inclusion criteria, lack of appropriate disease activity measures, and relapse criteria. This review outlines the disease activity indices used in SLE, discusses their advantages and disadvantages, and describes the ideal activity index.