Macrophage fumarate hydratase restrains mtRNA-mediated interferon production.

Metabolic rewiring underlies the effector functions of macrophages1-3, but the mechanisms involved remain incompletely defined. Here, using unbiased metabolomics and stable isotope-assisted tracing, we show that an inflammatory aspartate-argininosuccinate shunt is induced following lipopolysaccharide stimulation. The shunt, supported by increased argininosuccinate synthase (ASS1) expression, also leads to increased cytosolic fumarate levels and fumarate-mediated protein succination. Pharmacological inhibition and genetic ablation of the tricarboxylic acid cycle enzyme fumarate hydratase (FH) further increases intracellular fumarate levels. Mitochondrial respiration is also suppressed and mitochondrial membrane potential increased. RNA sequencing and proteomics analyses demonstrate that there are strong inflammatory effects resulting from FH inhibition. Notably, acute FH inhibition suppresses interleukin-10 expression, which leads to increased tumour necrosis factor secretion, an effect recapitulated by fumarate esters. Moreover, FH inhibition, but not fumarate esters, increases interferon-ß production through mechanisms that are driven by mitochondrial RNA (mtRNA) release and activation of the RNA sensors TLR7, RIG-I and MDA5. This effect is recapitulated endogenously when FH is suppressed following prolonged lipopolysaccharide stimulation. Furthermore, cells from patients with systemic lupus erythematosus also exhibit FH suppression, which indicates a potential pathogenic role for this process in human disease. We therefore identify a protective role for FH in maintaining appropriate macrophage cytokine and interferon responses.

Baricitinib for systemic lupus erythematosus: a double-blind, randomised, placebo-controlled, phase 3 trial (SLE-BRAVE-I).

BACKGROUND: Baricitinib is an oral selective inhibitor of Janus kinase 1 and 2 approved for the treatment of rheumatoid arthritis, atopic dermatitis, and alopecia areata. In a 24-week phase 2 study in patients with systemic lupus erythematosus (SLE), baricitinib 4 mg significantly improved SLE disease activity compared with placebo. The objective of this trial was to evaluate the efficacy and safety of baricitinib in patients with active SLE in a 52-week phase 3 study. METHODS: In a multicentre, double-blind, randomised, placebo-controlled, parallel-group, phase 3 study, SLE-BRAVE-I, patients (aged ≥18 years) with active SLE receiving stable background therapy were randomly assigned 1:1:1 to baricitinib 4 mg, 2 mg, or placebo once daily for 52 weeks with standard of care. Glucocorticoid tapering was encouraged but not required per protocol. The primary endpoint was the proportion of patients reaching an SLE Responder Index (SRI)-4 response at week 52 in the baricitinib 4 mg treatment group compared with placebo. The primary endpoint was assessed by logistic regression analysis with baseline disease activity, baseline corticosteroid dose, region, and treatment group in the model. Efficacy analyses were done on a modified intention-to-treat population, comprising all participants who were randomly assigned and received at least one dose of investigational product. Safety analyses were done on all randomly assigned participants who received at least one dose of investigational product and who did not discontinue from the study for the reason of lost to follow-up at the first post-baseline visit. This study is registered with ClinicalTrials.gov, NCT03616912. FINDINGS: 760 participants were randomly assigned and received at least one dose of baricitinib 4 mg (n=252), baricitinib 2 mg (n=255), or placebo (n=253). A significantly greater proportion of participants who received baricitinib 4 mg (142 [57%]; odds ratio 1·57 [95% CI 1·09 to 2·27]; difference with placebo 10·8 [2·0 to 19·6]; p=0·016), but not baricitinib 2 mg (126 [50%]; 1·14 [0·79 to 1·65]; 3·9 [-4·9 to 12·6]; p=0·47), reached SRI-4 response compared with placebo (116 [46%]). There were no significant differences between the proportions of participants in either baricitinib group reaching any of the major secondary endpoints compared with placebo, including glucocorticoid tapering and time to first severe flare. 26 (10%) participants receiving baricitinib 4 mg had serious adverse events, 24 (9%) participants receiving baricitinib 2 mg, and 18 (7%) participants receiving placebo. The safety profile of baricitinib in participants with SLE was consistent with the known baricitinib safety profile. INTERPRETATION: The primary endpoint in this study was met for the 4 mg baricitinib group. However, key secondary endpoints were not. No new safety signals were observed. FUNDING: Eli Lilly and Company.

Remission and low disease activity are associated with lower healthcare costs: results from the Systemic Lupus International Collaborating Clinics (SLICC) inception cohort.

OBJECTIVES: This study aims to determine the independent impact of definitions of remission/low disease activity (LDA) on direct/indirect costs (DCs, ICs) in a multicentre inception cohort. METHODS: Patients from 31 centres in 10 countries were enrolled within 15 months of diagnosis and assessed annually. Five mutually exclusive disease activity states (DAS) were defined as (1) remission off-treatment: clinical (c) SLEDAI-2K=0, without prednisone/immunosuppressants; (2) remission on-treatment: cSLEDAI-2K=0, prednisone ≤5 mg/day and/or maintenance immunosuppressants; (3) LDA-Toronto Cohort (TC): cSLEDAI-2K≤2, without prednisone/immunosuppressants; (4) modified lupus LDA state (mLLDAS): SLEDAI-2K≤4, no activity in major organs/systems, no new activity, prednisone ≤7.5 mg/day and/or maintenance immunosuppressants and (5) active: all remaining assessments.At each assessment, patients were stratified into the most stringent DAS fulfilled and the proportion of time in a DAS since cohort entry was determined. Annual DCs/ICs (2021 Canadian dollars) were based on healthcare use and lost workforce/non-workforce productivity over the preceding year.The association between the proportion of time in a DAS and annual DC/IC was examined through multivariable random-effects linear regressions. RESULTS: 1692 patients were followed a mean of 9.7 years; 49.0% of assessments were active. Remission/LDA (per 25% increase in time in a remission/LDA state vs active) were associated with lower annual DC/IC: remission off-treatment (DC -$C1372; IC -$C2507), remission on-treatment (DC -$C973; IC -$C2604,) LDA-TC (DC -$C1158) and mLLDAS (DC -$C1040). There were no cost differences between remission/LDA states. CONCLUSIONS: Our data suggest that systemic lupus erythematosus patients who achieve remission, both off and on-therapy, and reductions in disease activity incur lower costs than those experiencing persistent disease activity.

Machine learning identifies clusters of longitudinal autoantibody profiles predictive of systemic lupus erythematosus disease outcomes.

OBJECTIVES: A novel longitudinal clustering technique was applied to comprehensive autoantibody data from a large, well-characterised, multinational inception systemic lupus erythematosus (SLE) cohort to determine profiles predictive of clinical outcomes. METHODS: Demographic, clinical and serological data from 805 patients with SLE obtained within 15 months of diagnosis and at 3-year and 5-year follow-up were included. For each visit, sera were assessed for 29 antinuclear antibodies (ANA) immunofluorescence patterns and 20 autoantibodies. K-means clustering on principal component analysis-transformed longitudinal autoantibody profiles identified discrete phenotypic clusters. One-way analysis of variance compared cluster enrolment demographics and clinical outcomes at 10-year follow-up. Cox proportional hazards model estimated the HR for survival adjusting for age of disease onset. RESULTS: Cluster 1 (n=137, high frequency of anti-Smith, anti-U1RNP, AC-5 (large nuclear speckled pattern) and high ANA titres) had the highest cumulative disease activity and immunosuppressants/biologics use at year 10. Cluster 2 (n=376, low anti-double stranded DNA (dsDNA) and ANA titres) had the lowest disease activity, frequency of lupus nephritis and immunosuppressants/biologics use. Cluster 3 (n=80, highest frequency of all five antiphospholipid antibodies) had the highest frequency of seizures and hypocomplementaemia. Cluster 4 (n=212) also had high disease activity and was characterised by multiple autoantibody reactivity including to antihistone, anti-dsDNA, antiribosomal P, anti-Sjögren syndrome antigen A or Ro60, anti-Sjögren syndrome antigen B or La, anti-Ro52/Tripartite Motif Protein 21, antiproliferating cell nuclear antigen and anticentromere B). Clusters 1 (adjusted HR 2.60 (95% CI 1.12 to 6.05), p=0.03) and 3 (adjusted HR 2.87 (95% CI 1.22 to 6.74), p=0.02) had lower survival compared with cluster 2. CONCLUSION: Four discrete SLE patient longitudinal autoantibody clusters were predictive of long-term disease activity, organ involvement, treatment requirements and mortality risk.

Remission and low disease activity (LDA) prevent damage accrual in patients with systemic lupus erythematosus: results from the Systemic Lupus International Collaborating Clinics (SLICC) inception cohort.

OBJECTIVE: To determine the independent impact of different definitions of remission and low disease activity (LDA) on damage accrual. METHODS: Patients with ≥2 annual assessments from a longitudinal multinational inception lupus cohort were studied. Five mutually exclusive disease activity states were defined: remission off-treatment: clinical Systemic Lupus Erythematosus Disease Activity Index (cSLEDAI)-2K=0, without prednisone or immunosuppressants; remission on-treatment: cSLEDAI-2K score=0, prednisone ≤5 mg/day and/or maintenance immunosuppressants; low disease activity Toronto cohort (LDA-TC): cSLEDAI-2K score of ≤2, without prednisone or immunosuppressants; modified lupus low disease activity (mLLDAS): Systemic Lupus Erythematosus Disease Activity Index-2K score of 4 with no activity in major organ/systems, no new disease activity, prednisone ≤7.5 mg/day and/or maintenance immunosuppressants; active: all remaining visits. Only the most stringent definition was used per visit. Antimalarials were allowed in all. The proportion of time that patients were in a specific state at each visit since cohort entry was determined. Damage accrual was ascertained with the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI). Univariable and multivariable generalised estimated equation negative binomial regression models were used. Time-dependent covariates were determined at the same annual visit as the disease activity state but the SDI at the subsequent visit. RESULTS: There were 1652 patients, 1464 (88.6%) female, mean age at diagnosis 34.2 (SD 13.4) years and mean follow-up time of 7.7 (SD 4.8) years. Being in remission off-treatment, remission on-treatment, LDA-TC and mLLDAS (per 25% increase) were each associated with a lower probability of damage accrual (remission off-treatment: incidence rate ratio (IRR)=0.75, 95% CI 0.70 to 0.81; remission on-treatment: IRR=0.68, 95% CI 0.62 to 0.75; LDA: IRR=0.79, 95% CI 0.68 to 0.92; and mLLDAS: IRR=0.76, 95% CI 0.65 to 0.89)). CONCLUSIONS: Remission on-treatment and off-treatment, LDA-TC and mLLDAS were associated with less damage accrual, even adjusting for possible confounders and effect modifiers.

Longitudinal analysis of ANA in the Systemic Lupus International Collaborating Clinics (SLICC) Inception Cohort.

OBJECTIVES: A perception derived from cross-sectional studies of small systemic lupus erythematosus (SLE) cohorts is that there is a marked discrepancy between antinuclear antibody (ANA) assays, which impacts on clinicians' approach to diagnosis and follow-up. We compared three ANA assays in a longitudinal analysis of a large international incident SLE cohort retested regularly and followed for 5 years. METHODS: Demographic, clinical and serological data was from 805 SLE patients at enrolment, year 3 and 5. Two HEp-2 indirect immunofluorescence assays (IFA1, IFA2), an ANA ELISA, and SLE-related autoantibodies were performed in one laboratory. Frequencies of positivity, titres or absorbance units (AU), and IFA patterns were compared using McNemar, Wilcoxon and kappa statistics, respectively. RESULTS: At enrolment, ANA positivity (≥1:80) was 96.1% by IFA1 (median titre 1:1280 (IQR 1:640-1:5120)), 98.3% by IFA2 (1:2560 (IQR 1:640-1:5120)) and 96.6% by ELISA (176.3 AU (IQR 106.4 AU-203.5 AU)). At least one ANA assay was positive for 99.6% of patients at enrolment. At year 5, ANA positivity by IFAs (IFA1 95.2%; IFA2 98.9%) remained high, while there was a decrease in ELISA positivity (91.3%, p<0.001). Overall, there was >91% agreement in ANA positivity at all time points and ≥71% agreement in IFA patterns between IFA1 and IFA2. CONCLUSION: In recent-onset SLE, three ANA assays demonstrated commutability with a high proportion of positivity and titres or AU. However, over 5 years follow-up, there was modest variation in ANA assay performance. In clinical situations where the SLE diagnosis is being considered, a negative test by either the ELISA or HEp-2 IFA may require reflex testing.

Safety of belimumab in adult patients with systemic lupus erythematosus: Results of a large integrated analysis of controlled clinical trial data.

OBJECTIVES: Systemic lupus erythematosus (SLE) is a chronic, autoimmune disease that affects multiple organ systems. Belimumab, a targeted human monoclonal antibody, binds to and inhibits soluble B-lymphocyte stimulator. The safety and efficacy of belimumab has consistently been demonstrated in multiple clinical trials for the treatment of patients with active SLE. Integration of these data provides an additional opportunity to explore the safety of belimumab in a larger and more diverse population. This post hoc pooled analysis of clinical studies evaluated the safety profile of belimumab versus placebo in adults with SLE. METHODS: This was a pooled post hoc analysis of 52-week safety data from one Phase 2 and five Phase 3 belimumab trials in adult patients with SLE. Patients received ≥1 dose of placebo or belimumab (1, 4, or 10 mg/kg intravenous or 200 mg subcutaneous), plus standard therapy. Outcomes included the incidence of adverse events (AEs), serious AEs (SAEs), severe AEs, AEs of special interest (AESI), and mortality. RESULTS: Across 4170 patients (placebo: N = 1355; belimumab: N = 2815), baseline demographics, disease characteristics, and treatment exposure were similar for placebo and belimumab. Most patients (placebo: 76.6%; belimumab: 81.0%) completed the protocol Week 52 visit. Overall, incidence of AEs, SAEs, severe AEs, AESI, and mortality were similar between groups. In both groups, the most commonly reported SAEs by system organ class were infections and infestations (placebo: 5.9%; belimumab: 5.4%) and renal and urinary disorders (placebo: 2.2%; belimumab: 1.7%). Additionally, a greater proportion of patients experienced AESI with belimumab versus placebo for post-infusion/injection systemic reactions (placebo: 8.1%; belimumab: 10.2%). Mortality rates were similar between groups (placebo: 0.4%; belimumab: 0.6%). CONCLUSIONS: These results are consistent with those of the individual studies, BASE, BLISS-LN, and long-term extension studies, making belimumab one of the most studied SLE treatments for safety. Collectively, this evidence continues to support a positive benefit-risk profile of belimumab in the treatment of adult patients with SLE.

New Insights Into Systemic Lupus Erythematosus Therapies: 2010-2020.

ABSTRACT: Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that may affect every organ. The multiple pathogenic mechanisms and heterogeneous phenotypes of SLE present unique challenges in the management of this complex disease. This article discusses new SLE therapies from the last 10 years. We will address new information in the realms of lifestyle interventions, antimalarials, nonsteroidal anti-inflammatory drugs, glucocorticoids, immunosuppressive disease modifying antirheumatic drugs, biological therapies, and other modalities as they pertain to SLE.

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.

Genetic fine mapping of systemic lupus erythematosus MHC associations in Europeans and African Americans.

Genetic variation within the major histocompatibility complex (MHC) contributes substantial risk for systemic lupus erythematosus, but high gene density, extreme polymorphism and extensive linkage disequilibrium (LD) have made fine mapping challenging. To address the problem, we compared two association techniques in two ancestrally diverse populations, African Americans (AAs) and Europeans (EURs). We observed a greater number of Human Leucocyte Antigen (HLA) alleles in AA consistent with the elevated level of recombination in this population. In EUR we observed 50 different A-C-B-DRB1-DQA-DQB multilocus haplotype sequences per hundred individuals; in the AA sample, these multilocus haplotypes were twice as common compared to Europeans. We also observed a strong narrow class II signal in AA as opposed to the long-range LD observed in EUR that includes class I alleles. We performed a Bayesian model choice of the classical HLA alleles and a frequentist analysis that combined both single nucleotide polymorphisms (SNPs) and classical HLA alleles. Both analyses converged on a similar subset of risk HLA alleles: in EUR HLA- B*08:01 + B*18:01 + (DRB1*15:01 frequentist only) + DQA*01:02 + DQB*02:01 + DRB3*02 and in AA HLA-C*17:01 + B*08:01 + DRB1*15:03 + (DQA*01:02 frequentist only) + DQA*02:01 + DQA*05:01+ DQA*05:05 + DQB*03:19 + DQB*02:02. We observed two additional independent SNP associations in both populations: EUR rs146903072 and rs501480; AA rs389883 and rs114118665. The DR2 serotype was best explained by DRB1*15:03 + DQA*01:02 in AA and by DRB1*15:01 + DQA*01:02 in EUR. The DR3 serotype was best explained by DQA*05:01 in AA and by DQB*02:01 in EUR. Despite some differences in underlying HLA allele risk models in EUR and AA, SNP signals across the extended MHC showed remarkable similarity and significant concordance in direction of effect for risk-associated variants.

Neuropsychiatric events in systemic lupus erythematosus: a longitudinal analysis of outcomes in an international inception cohort using a multistate model approach.

OBJECTIVES: Using a reversible multistate model, we prospectively examined neuropsychiatric (NP) events for attribution, outcome and association with health-related quality of life (HRQoL), in an international, inception cohort of systemic lupus erythematosus (SLE) patients. METHODS: Annual assessments for 19 NP events attributed to SLE and non-SLE causes, physician determination of outcome and patient HRQoL (short-form (SF)-36 scores) were measured. Time-to-event analysis and multistate modelling examined the onset, recurrence and transition between NP states. RESULTS: NP events occurred in 955/1827 (52.3%) patients and 592/1910 (31.0%) unique events were attributed to SLE. In the first 2 years of follow-up the relative risk (95% CI) for SLE NP events was 6.16 (4.96, 7.66) and non-SLE events was 4.66 (4.01, 5.43) compared with thereafter. Patients without SLE NP events at initial assessment had a 74% probability of being event free at 10 years. For non-SLE NP events the estimate was 48%. The majority of NP events resolved over 10 years but mortality was higher in patients with NP events attributed to SLE (16%) versus patients with no NPSLE events (6%) while the rate was comparable in patients with non-SLE NP events (7%) compared with patients with no non-SLE events (6%). Patients with NP events had lower SF-36 summary scores compared with those without NP events and resolved NP states (p<0.001). CONCLUSIONS: NP events occur most frequently around the diagnosis of SLE. Although the majority of events resolve they are associated with reduced HRQoL and excess mortality. Multistate modelling is well suited for the assessment of NP events in SLE.

Soluble urokinase plasminogen activator receptor (suPAR) levels predict damage accrual in patients with recent-onset systemic lupus erythematosus.

OBJECTIVE: The soluble urokinase plasminogen activator receptor (suPAR) has potential as a prognosis and severity biomarker in several inflammatory and infectious diseases. In a previous cross-sectional study, suPAR levels were shown to reflect damage accrual in cases of systemic lupus erythematosus (SLE). Herein, we evaluated suPAR as a predictor of future organ damage in recent-onset SLE. METHODS: Included were 344 patients from the Systemic Lupus International Collaborating Clinics (SLICC) Inception Cohort who met the 1997 American College of Rheumatology classification criteria with 5-years of follow-up data available. Baseline sera from patients and age- and sex-matched controls were assayed for suPAR. Organ damage was assessed annually using the SLICC/ACR damage index (SDI). RESULTS: The levels of suPAR were higher in patients who accrued damage, particularly those with SDI≥2 at 5 years (N = 32, 46.8% increase, p = 0.004), as compared to patients without damage. Logistic regression analysis revealed a significant impact of suPAR on SDI outcome (SDI≥2; OR = 1.14; 95% CI 1.03-1.26), also after adjustment for confounding factors. In an optimized logistic regression to predict damage, suPAR persisted as a predictor, together with baseline disease activity (SLEDAI-2K), age, and non-Caucasian ethnicity (model AUC = 0.77). Dissecting SDI into organ systems revealed higher suPAR levels in patients who developed musculoskeletal damage (SDI≥1; p = 0.007). CONCLUSION: Prognostic biomarkers identify patients who are at risk of acquiring early damage and therefore need careful observation and targeted treatment strategies. Overall, suPAR constitutes an interesting biomarker for patient stratification and for identifying SLE patients who are at risk of acquiring organ damage during the first 5 years of disease.

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

OBJECTIVE: Low disease activity (LDA) and remission are emerging treat-to-target (T2T) endpoints in SLE. However, the rates at which these endpoints are met in patients with high disease activity (HDA) are unknown. Atacicept, which targets B lymphocyte stimulator and a proliferation-inducing ligand, improved disease outcomes in SLE patients with HDA (SLEDAI-2K ≥10) at baseline in the phase 2b ADDRESS II study. This is a post hoc analysis of T2T endpoints in these patients. METHODS: Patients received weekly atacicept (75 or 150 mg s.c.) or placebo for 24 weeks (1:1:1 randomization). Attainment of three T2T endpoints, LDA (SLEDAI-2K ≤ 2), Lupus Low Disease Activity State (LLDAS) and remission (clinical SLEDAI-2K = 0, prednisone-equivalent ≤5mg/day and Physician's Global Assessment <0.5), was assessed and compared with SLE Responder Index (SRI)-4 and SRI-6 response. RESULTS: Of 306 randomized patients, 158 (51.6%) had baseline HDA. At week 24, 37 (23.4%) HDA patients attained LDA, 25 (15.8%) LLDAS and 17 (10.8%) remission. Each of these endpoints was more stringent than SRI-4 (n = 87; 55.1%) and SRI-6 (n = 67; 42.4%). Compared with placebo (n = 52), at week 24, patients treated with atacicept 150 mg (n = 51) were more likely to attain LDA [odds ratio (OR) 3.82 (95% CI: 1.44, 10.15), P = 0.007], LLDAS [OR 5.03 (95% CI: 1.32, 19.06), P = 0.018] or remission [OR 3.98 (95% CI: 0.78, 20.15), P = 0.095]. CONCLUSION: At week 24, LDA, LLDAS and remission were more stringent than SRI-4 and SRI-6 response, were attainable in the HDA population and discriminated between treatment with atacicept 150 mg and placebo. These results suggest that T2T endpoints are robust outcome measures in SLE clinical trials and support further evaluation of atacicept in SLE. TRAIL REGISTRATION: ClinicalTrials.gov, http://clinicaltrials.gov, NCT01972568.

Unique Sjögren's syndrome patient subsets defined by molecular features.

OBJECTIVE: To address heterogeneity complicating primary SS (pSS) clinical trials, research and care by characterizing and clustering patients by their molecular phenotypes. METHODS: pSS patients met American-European Consensus Group classification criteria and had at least one systemic manifestation and stimulated salivary flow of ⩾0.1 ml/min. Correlated transcriptional modules were derived from gene expression microarray data from blood (n = 47 with appropriate samples). Patients were clustered based on this molecular information using an unbiased random forest modelling approach. In addition, multiplex, bead-based assays and ELISAs were used to assess 30 serum cytokines, chemokines and soluble receptors. Eleven autoantibodies, including anti-Ro/SSA and anti-La/SSB, were measured by Bio-Rad Bioplex 2200. RESULTS: Transcriptional modules distinguished three clusters of pSS patients. Cluster 1 showed no significant elevation of IFN or inflammation modules. Cluster 2 showed strong IFN and inflammation modular network signatures, as well as high plasma protein levels of IP-10/CXCL10, MIG/CXCL9, BLyS (BAFF) and LIGHT. Cluster 3 samples exhibited moderately elevated IFN modules, but with suppressed inflammatory modules, increased IP-10/CXCL10 and B cell-attracting chemokine 1/CXCL13 and trends toward increased MIG/CXCL9, IL-1α, and IL-21. Anti-Ro/SSA and anti-La/SSB were present in all three clusters. CONCLUSION: Molecular profiles encompassing IFN, inflammation and other signatures can be used to separate patients with pSS into distinct clusters. In the future, such profiles may inform patient selection for clinical trials and guide treatment decisions.

Identification of a Sjögren's syndrome susceptibility locus at OAS1 that influences isoform switching, protein expression, and responsiveness to type I interferons.

Sjögren's syndrome (SS) is a common, autoimmune exocrinopathy distinguished by keratoconjunctivitis sicca and xerostomia. Patients frequently develop serious complications including lymphoma, pulmonary dysfunction, neuropathy, vasculitis, and debilitating fatigue. Dysregulation of type I interferon (IFN) pathway is a prominent feature of SS and is correlated with increased autoantibody titers and disease severity. To identify genetic determinants of IFN pathway dysregulation in SS, we performed cis-expression quantitative trait locus (eQTL) analyses focusing on differentially expressed type I IFN-inducible transcripts identified through a transcriptome profiling study. Multiple cis-eQTLs were associated with transcript levels of 2'-5'-oligoadenylate synthetase 1 (OAS1) peaking at rs10774671 (PeQTL = 6.05 × 10-14). Association of rs10774671 with SS susceptibility was identified and confirmed through meta-analysis of two independent cohorts (Pmeta = 2.59 × 10-9; odds ratio = 0.75; 95% confidence interval = 0.66-0.86). The risk allele of rs10774671 shifts splicing of OAS1 from production of the p46 isoform to multiple alternative transcripts, including p42, p48, and p44. We found that the isoforms were differentially expressed within each genotype in controls and patients with and without autoantibodies. Furthermore, our results showed that the three alternatively spliced isoforms lacked translational response to type I IFN stimulation. The p48 and p44 isoforms also had impaired protein expression governed by the 3' end of the transcripts. The SS risk allele of rs10774671 has been shown by others to be associated with reduced OAS1 enzymatic activity and ability to clear viral infections, as well as reduced responsiveness to IFN treatment. Our results establish OAS1 as a risk locus for SS and support a potential role for defective viral clearance due to altered IFN response as a genetic pathophysiological basis of this complex autoimmune disease.

Baricitinib for systemic lupus erythematosus: a double-blind, randomised, placebo-controlled, phase 2 trial.

BACKGROUND: Patients with systemic lupus erythematosus have substantial unmet medical need. Baricitinib is an oral selective Janus kinase (JAK)1 and JAK2 inhibitor that we hypothesised might have therapeutic benefit in patients with systemic lupus erythematosus. METHODS: In this double-blind, multicentre, randomised, placebo-controlled, 24-week phase 2 study, patients were recruited from 78 centres in 11 countries. Eligible patients were aged 18 years or older, had a diagnosis of systemic lupus erythematosus, and had active disease involving skin or joints. We randomly assigned patients (1:1:1) to receive once-daily baricitinib 2 mg, baricitinib 4 mg, or placebo for 24 weeks. The primary endpoint was the proportion of patients achieving resolution of arthritis or rash at week 24, as defined by Systemic Lupus Erythematosus Disease Activity Index-2000 (SLEDAI-2K). Efficacy and safety analyses included all patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov, number NCT02708095. FINDINGS: Between March 24, 2016, and April 27, 2017, 314 patients were randomly assigned to receive placebo (n=105), baricitinib 2 mg (n=105), or baricitinib 4 mg (n=104). At week 24, resolution of SLEDAI-2K arthritis or rash was achieved by 70 (67%) of 104 patients receiving baricitinib 4 mg (odds ratio [OR] vs placebo 1·8, 95% CI 1·0-3·3; p=0·0414) and 61 (58%) of 105 patients receiving baricitinib 2 mg (OR 1·3, 0·7-2·3; p=0·39). Adverse events were reported in 68 (65%) patients in the placebo group, 75 (71%) patients in the baricitinib 2 mg group, and 76 (73%) patients in the baricitinib 4 mg group. Serious adverse events were reported in ten (10%) patients receiving baricitinib 4 mg, 11 (10%) receiving baricitinib 2 mg, and five (5%) receiving placebo; no deaths were reported. Serious infections were reported in six (6%) patients with baricitinib 4 mg, two (2%) with baricitinib 2 mg, and one (1%) with placebo. INTERPRETATION: The baricitinib 4 mg dose, but not the 2 mg dose, significantly improved the signs and symptoms of active systemic lupus erythematosus in patients who were not adequately controlled despite standard of care therapy, with a safety profile consistent with previous studies of baricitinib. This study provides the foundation for future phase 3 trials of JAK1/2 inhibition with baricitinib as a new potential oral therapy for systemic lupus erythematosus. FUNDING: Eli Lilly and Company.

Association of Epstein-Barr virus serological reactivation with transitioning to systemic lupus erythematosus in at-risk individuals.

OBJECTIVE: Systemic lupus erythematosus (SLE) is a systemic autoimmune disease with unknown aetiology. Epstein-Barr virus (EBV) is an environmental factor associated with SLE. EBV maintains latency in B cells with frequent reactivation measured by antibodies against viral capsid antigen (VCA) and early antigen (EA). In this study, we determined whether EBV reactivation and single nucleotide polymorphisms (SNPs) in EBV-associated host genes are associated with SLE transition. METHODS: SLE patient relatives (n=436) who did not have SLE at baseline were recontacted after 6.3 (±3.9) years and evaluated for interim transitioning to SLE (≥4 cumulative American College of Rheumatology criteria); 56 (13%) transitioned to SLE prior to the follow-up visit. At both visits, detailed demographic, environmental, clinical information and blood samples were obtained. Antibodies against viral antigens were measured by ELISA. SNPs in IL10, CR2, TNFAIP3 and CD40 genes were typed by ImmunoChip. Generalised estimating equations were used to test associations between viral antibody levels and transitioning to SLE. RESULTS: Mean baseline VCA IgG (4.879±1.797 vs 3.866±1.795, p=0.0003) and EA IgG (1.192±1.113 vs 0.7774±0.8484, p=0.0236) levels were higher in transitioned compared with autoantibody negative non-transitioned relatives. Increased VCA IgG and EA IgG were associated with transitioning to SLE (OR 1.28 95% CI 1.07 to 1.53, p=0.007, OR 1.43 95% CI 1.06 to 1.93, p=0.02, respectively). Significant interactions were observed between CD40 variant rs48100485 and VCA IgG levels and IL10 variant rs3024493 and VCA IgA levels in transitioning to SLE. CONCLUSION: Heightened serologic reactivation of EBV increases the probability of transitioning to SLE in unaffected SLE relatives.

Use of combined hormonal contraceptives among women with systemic lupus erythematosus with and without medical contraindications to oestrogen.

OBJECTIVES: To assess the prevalence of combined hormonal contraceptives (CHCs) in reproductive-age women with SLE with and without possible contraindications and to determine factors associated with their use in the presence of possible contraindications. METHODS: This observational cohort study included premenopausal women ages 18-45 years enrolled in the SLICC Registry ⩽15 months after SLE onset, with annual assessments spanning 2000-2017. World Health Organization Category 3 or 4 contraindications to CHCs (e.g. hypertension, aPL) were assessed at each study visit. High disease activity (SLEDAI score >12 or use of >0.5 mg/kg/day of prednisone) was considered a relative contraindication. RESULTS: A total of 927 SLE women contributed 6315 visits, of which 3811 (60%) occurred in the presence of one or more possible contraindication to CHCs. Women used CHCs during 512 (8%) visits, of which 281 (55%) took place in the setting of one or more possible contraindication. The most frequently observed contraindications were aPL (52%), hypertension (34%) and migraine with aura (22%). Women with one or more contraindication were slightly less likely to be taking CHCs [7% of visits (95% CI 7, 8)] than women with no contraindications [9% (95% CI 8, 10)]. CONCLUSION: CHC use was low compared with general population estimates (>35%) and more than half of CHC users had at least one possible contraindication. Many yet unmeasured factors, including patient preferences, may have contributed to these observations. Further work should also aim to clarify outcomes associated with this exposure.