Kenneth C. Kalunian

Derivation and validation of the systemic lupus international collaborating clinics classification criteria for systemic lupus erythematosus

OBJECTIVE The Systemic Lupus International Collaborating Clinics (SLICC) group revised and validated the American College of Rheumatology (ACR) systemic lupus erythematosus (SLE) classification criteria in order to improve clinical relevance, meet stringent methodology requirements, and incorporate new knowledge regarding the immunology of SLE. METHODS The classification criteria were derived from a set of 702 expert-rated patient scenarios. Recursive partitioning was used to derive an initial rule that was simplified and refined based on SLICC physician consensus. The SLICC group validated the classification criteria in a new validation sample of 690 new expert-rated patient scenarios. RESULTS Seventeen criteria were identified. In the derivation set, the SLICC classification criteria resulted in fewer misclassifications compared with the current ACR classification criteria (49 versus 70; P = 0.0082) and had greater sensitivity (94% versus 86%; P < 0.0001) and equal specificity (92% versus 93%; P = 0.39). In the validation set, the SLICC classification criteria resulted in fewer misclassifications compared with the current ACR classification criteria (62 versus 74; P = 0.24) and had greater sensitivity (97% versus 83%; P < 0.0001) but lower specificity (84% versus 96%; P < 0.0001). CONCLUSION The new SLICC classification criteria performed well in a large set of patient scenarios rated by experts. According to the SLICC rule for the classification of SLE, the patient must satisfy at least 4 criteria, including at least one clinical criterion and one immunologic criterion OR the patient must have biopsy-proven lupus nephritis in the presence of antinuclear antibodies or anti-double-stranded DNA antibodies.

Evidence for linkage of a candidate chromosome 1 region to human systemic lupus erythematosus.

Genetic susceptibility confers significant risk for systemic lupus erythematosus (SLE). The MHC region and other polymorphic loci have been associated with SLE. Because more compelling evidence for an involvement of a genetic locus includes linkage, we tested a candidate region homologous to a murine SLE susceptibility region in 52 SLE-affected sibpairs from three ethnic groups. We analyzed seven microsatellite markers from the human chromosome 1q31-q42 region corresponding to the telomeric end of mouse chromosome 1, the region where specific manifestations of murine lupus, including glomerulonephritis and IgG antichromatin, have been mapped. Comparing the mean allele sharing in affected sibpairs of each of these seven markers to their expected values of 0.50, only the five markers located at 1q41-q42 showed evidence for linkage (P = 0.0005-0.08). Serum levels of IgG antichromatin also showed evidence for linkage to two of these five markers (P = 0.04), suggesting that this phenotype is conserved between mice and humans. Compared to the expected random distribution, the trend of increased sharing of haplotypes was observed in affected sibpairs from three ethnic groups (P < 0.01). We concluded that this candidate 1q41-q42 region probably contains a susceptibility gene(s) that confers risk for SLE in multiple ethnic groups.

Efficacy and safety of epratuzumab in patients with moderate/severe active systemic lupus erythematosus: results from EMBLEM, a phase IIb, randomised, double-blind, placebo-controlled, multicentre study

Objective To identify a suitable dosing regimen of the CD22-targeted monoclonal antibody epratuzumab in adults with moderately to severely active systemic lupus erythematosus (SLE). Methods A phase IIb, multicentre, randomised controlled study (NCT00624351) was conducted with 227 patients (37–39 per arm) receiving either: placebo, epratuzumab 200 mg cumulative dose (cd) (100 mg every other week (EOW)), 800 mg cd (400 mg EOW), 2400 mg cd (600 mg weekly), 2400 mg cd (1200 mg EOW), or 3600 mg cd (1800 mg EOW). The primary endpoint (not powered for significance) was the week 12 responder rate measured using a novel composite endpoint, the British Isles Lupus Assessment Group (BILAG)-based Combined Lupus Assessment (BICLA). Results Proportion of responders was higher in all epratuzumab groups than with placebo (overall treatment effect test p=0.148). Exploratory pairwise analysis demonstrated clinical improvement in patients receiving a cd of 2400 mg epratuzumab (OR for 600 mg weekly vs placebo: 3.2 (95% CI 1.1 to 8.8), nominal p=0.03; OR for 1200 mg EOW vs placebo: 2.6 (0.9 to 7.1), nominal p=0.07). Post-hoc comparison of all 2400 mg cd patients versus placebo found an overall treatment effect (OR=2.9 (1.2 to 7.1), nominal p=0.02). Incidence of adverse events (AEs), serious AEs and infusion reactions was similar between epratuzumab and placebo groups, without decreases in immunoglobulin levels and only partial reduction in B-cell levels. Conclusions Treatment with epratuzumab 2400 mg cd was well tolerated in patients with moderately to severely active SLE, and associated with improvements in disease activity. Phase III studies are ongoing.

Sifalimumab, a Human Anti–Interferon‐α Monoclonal Antibody, in Systemic Lupus Erythematosus: A Phase I Randomized, Controlled, Dose‐Escalation Study

Objective To evaluate the safety and tolerability of multiple intravenous (IV) doses of sifalimumab in adults with moderate-to-severe systemic lupus erythematosus (SLE). Methods In this multicenter, double-blind, placebo-controlled, sequential dose-escalation study, patients were randomized 3:1 to receive IV sifalimumab (0.3, 1.0, 3.0, or 10.0 mg/kg) or placebo every 2 weeks to week 26, then followed up for 24 weeks. Safety assessment included recording of treatment-emergent adverse events (AEs) and serious AEs. Pharmacokinetics, immunogenicity, and pharmacodynamics were evaluated, and disease activity was assessed. Results Of 161 patients, 121 received sifalimumab (26 received 0.3 mg/kg; 25, 1.0 mg/kg; 27, 3.0 mg/kg; and 43, 10 mg/kg) and 40 received placebo. Patients were predominantly female (95.7%). At baseline, patients had moderate-to-severe disease activity (mean SLE Disease Activity Index score 11.0), and most (75.2%) had a high type I interferon (IFN) gene signature. In the sifalimumab group versus the placebo group, the incidence of ≥1 treatment-emergent AE was 92.6% versus 95.0%, ≥1 serious AE was 22.3% versus 27.5%, and ≥1 infection was 67.8% versus 62.5%; discontinuations due to AEs occurred in 9.1% versus 7.5%, and death occurred in 3.3% (n = 4) versus 2.5% (n = 1). Serum sifalimumab concentrations increased in a linear and dose-proportional manner. Inhibition of the type I IFN gene signature was sustained during treatment in patients with a high baseline signature. No statistically significant differences in clinical activity (SLEDAI and British Isles Lupus Assessment Group score) between sifalimumab and placebo were observed. However, when adjusted for excess burst steroids, SLEDAI change from baseline showed a positive trend over time. A trend toward normal complement C3 or C4 level at week 26 was seen in the sifalimumab groups compared with baseline. Conclusion The observed safety/tolerability and clinical activity profile of sifalimumab support its continued clinical development for SLE.

Clinical significance of a single test for anti-cardiolipin antibodies in patients with systemic lupus erythematosus

PURPOSE Clinicians have difficulty interpreting results of tests for anti-cardiolipin antibodies (aCL) because of conflicting reports of the clinical associations of these antibodies in patients with systemic lupus erythematosus (SLE). We therefore decided to evaluate the clinical associations of aCL in an effort to facilitate interpretation of single reports of either positive or negative test results. We also assessed the role of estrogen on the development of aCL. PATIENTS AND METHODS The study population consisted of 85 consecutive outpatients with SLE and 40 control subjects. Serum samples and clinical and laboratory data were obtained from each patient and control. Testing for aCL was performed using a standardized enzyme-linked immunoabsorbent assay developed at an international workshop. RESULTS The presence of aCL was documented in 42.4 percent of patients with SLE and 7.5 percent of control subjects. In patients with SLE, these antibodies were significantly associated with thrombosis, fetal loss, and thrombocytopenia, but not with other manifestations. Measurement of all isotypes optimized clinical correlations. Titers did not add clinical utility. Fluctuations of levels of aCL occurred, making it difficult to interpret a single negative result. Among control subjects, the presence of aCL was not significantly more common in women who used oral contraceptives. CONCLUSION Our findings suggest that positive results of testing for aCL correlate with a predisposition for thrombosis, fetal loss, and thrombocytopenia in patients with SLE; however, the test is not predictive for other clinical manifestations of SLE, including activity and severity of disease. We believe that measurement of all isotypes of aCL should be performed in patients with SLE considering pregnancy, to identify those with a high risk of fetal loss, and in SLE patients with a thrombotic episode.

PARP alleles within the linked chromosomal region are associated with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by various autoantibodies that recognize autoantigens displayed on the surface of cells undergoing apoptosis. The genetic contribution to SLE susceptibility has been widely recognized. We previously reported evidence for linkage to SLE of the human chromosome 1q41-q42 region and have now narrowed it from 15 to 5 cM in an extended sample using multipoint linkage analysis. Candidate genes within this region include (a) PARP, poly(ADP-ribose) polymerase, encoding a zinc-finger DNA-binding protein that is involved in DNA repair and apoptosis; (b) TGFB2, encoding a transforming growth factor that regulates cellular interactions and responses; and (c) HLX1, encoding a homeobox protein that may regulate T-cell development. Using a multiallelic, transmission-disequilibrium test (TDT), we found overall skewing of transmission of PARP alleles to affected offspring in 124 families (P = 0.00008), preferential transmission of a PARP allele to affected offspring (P = 0.0003), and lack of transmission to unaffected offspring (P = 0.004). Similar TDT analyses of TGFB2 and HLX1 polymorphisms yielded no evidence for association with SLE. These results suggest that PARP may be (or is close to) the susceptibility gene within the chromosome 1q41-q42 region linked to SLE.

Autoantibodies and neuropsychiatric events at the time of systemic lupus erythematosus diagnosis: Results from an international inception cohort study

OBJECTIVE To examine, in an inception cohort of systemic lupus erythematosus (SLE) patients, the association between neuropsychiatric (NP) events and anti-ribosomal P (anti-P), antiphospholipid (lupus anticoagulant [LAC], anticardiolipin), anti-beta2-glycoprotein I, and anti-NR2 glutamate receptor antibodies. METHODS NP events were identified using the American College of Rheumatology case definitions and clustered into central/peripheral and diffuse/focal events. Attribution of NP events to SLE was determined using decision rules of differing stringency. Autoantibodies were measured without knowledge of NP events or their attribution. RESULTS Four hundred twelve patients were studied (87.4% female; mean +/- SD age 34.9 +/- 13.5 years, mean +/- SD disease duration 5.0 +/- 4.2 months). There were 214 NP events in 133 patients (32.3%). The proportion of NP events attributed to SLE varied from 15% to 36%. There was no association between autoantibodies and NP events overall. However, the frequency of anti-P antibodies in patients with central NP events attributed to SLE was 4 of 20 (20%), versus 3 of 107 (2.8%) in patients with other NP events and 24 of 279 (8.6%) in those with no NP events (P = 0.04). Among patients with diffuse NP events, 3 of 11 had anti-P antibodies (27%), compared with 4 of 111 patients with other NP events (3.6%) and 24 of 279 of those with no NP events (8.6%) (P = 0.02). Specific clinical-serologic associations were found between anti-P and psychosis attributed to SLE (P = 0.02) and between LAC and cerebrovascular disease attributed to SLE (P = 0.038). There was no significant association between other autoantibodies and NP events. CONCLUSION Clinically distinct NP events attributed to SLE and occurring around the time of diagnosis were found to be associated with anti-P antibodies and LAC. This suggests that there are different autoimmune pathogenetic mechanisms, although low sensitivity limits the clinical application of testing for these antibodies.

Atherosclerotic vascular events in a multinational inception cohort of systemic lupus erythematosus

To describe vascular events during an 8‐year followup in a multicenter systemic lupus erythematosus (SLE) inception cohort and their attribution to atherosclerosis.

A Phase II study of the efficacy and safety of rontalizumab (rhuMAb interferon-α) in patients with systemic lupus erythematosus (ROSE)

Objectives To examine the safety and efficacy of rontalizumab, a humanised IgG1 anti-interferon α (anti-IFN-α) monoclonal antibody, in patients with moderate-to-severe systemic lupus erythematosus (SLE). Methods Patients with active SLE were randomised (2:1) to 750 mg intravenous rontalizumab every 4 weeks or placebo (Part 1), and 300 mg subcutaneous rontalizumab every 2 weeks or placebo (Part 2). Background Hydroxychloroquine and corticosteroids were allowed. Patients taking immunosuppressants at baseline were required per protocol to discontinue. Efficacy end points included reduction in disease activity by British Isles Lupus Disease Activity Group (BILAG)-2004 (primary), and SLE response index (SRI, secondary) at Week 24. Efficacy was also examined by an exploratory measure of IFN-regulated gene expression (interferon signature metric, ISM). Results Patients (n=238) received rontalizumab (n=159) or placebo (n=79). At baseline, the mean Safety of Estrogens in Lupus Erythematosus National Assessment version of the SLE Disease Activity Index (SELENA-SLEDAI) score in all cohorts was ∼10, and 75.6% of patients had a high ISM (ISM-High). Efficacy response rates by BILAG and SRI were similar between rontalizumab and placebo groups. However, in the exploratory subgroup of ISM-Low patients, SRI response was higher and steroid use was lower in the rontalizumab-treated patients. There was also a reduction in SELENA-SLEDAI flare index rates (HR 0.61, 0.46 to 0.81, p=0.004) in this subgroup. Adverse events were similar between placebo and rontalizumab groups. Conclusions The primary and secondary end points of this trial were not met in all patients or in patients with high ISM scores. In an exploratory analysis, rontalizumab treatment was associated with improvements in disease activity, reduced flares and decreased steroid use in patients with SLE with low ISM scores. Trial registration number NCT00962832.

Anifrolumab, an Anti–Interferon‐α Receptor Monoclonal Antibody, in Moderate‐to‐Severe Systemic Lupus Erythematosus

To assess the efficacy and safety of anifrolumab, a type I interferon (IFN) receptor antagonist, in a phase IIb, randomized, double‐blind, placebo‐controlled study of adults with moderate‐to‐severe systemic lupus erythematosus (SLE).