Objective The Systemic Lupus Collaborating Clinics (SLICC) revised and validated the American College of Rheumatology (ACR) SLE classification criteria in order to improve clinical relevance, meet stringent methodology requirements and incorporate new knowledge in SLE immunology. 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. SLICC validated the classification criteria in a new validation sample of 690 SLE patients and controls. Results Seventeen criteria were identified. The SLICC criteria for SLE classification requires: 1) Fulfillment of at least four criteria, with at least one clinical criterion AND one immunologic criterion OR 2) Lupus nephritis as the sole clinical criterion in the presence of ANA or anti-dsDNA antibodies. In the derivation set, the SLICC classification criteria resulted in fewer misclassifications than the current ACR classification criteria (49 versus 70, p=0.0082), 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 (62 versus 74, p=0.24), had greater sensitivity (97% versus 83%, p<0.0001) but less specificity (84% versus 96%, p<0.0001). Conclusions The new SLICC classification criteria performed well on a large set of patient scenarios rated by experts. They require that at least one clinical criterion and one immunologic criterion be present for a classification of SLE. Biopsy confirmed nephritis compatible with lupus (in the presence of SLE autoantibodies) is sufficient for classification.

Objective. To develop and perform an initial validation of a damage index for systemic lupus erythematosus (SLE). Methods.A list of items considered to reflect damage in SLE was generated through a nominal group

Objective To assess the efficacy/safety of the B-lymphocyte stimulator inhibitor belimumab/standard-of-care (SOC) versus placebo/SOC in active systemic lupus erythematosus (SLE). Methods In a multicenter, randomized, controlled, phase 3 trial, 819 antinuclear antibody- or anti-dsDNA-positive SLE patients with Safety of Estrogens in Lupus Erythematosus National Assessment–SLE Disease Activity Index (SELENA-SLEDAI) ≥ 6 were randomized (1:1:1 ratio) to receive intravenous belimumab 1 or 10 mg/kg, or placebo on days 0, 14, and 28, and then every 28 days for 72 weeks. Primary efficacy analyses: SLE Responder Index (SRI) at week 52 (≥ 4-point reduction in SELENA-SLEDAI; no new British Isles Lupus Assessment Group A and < 2 new B organ domain scores; no worsening in Physician’s Global Assessment). Results Belimumab 10 mg/kg plus SOC met the primary efficacy endpoint: significantly greater SRI response at week 52 than placebo (43.2% versus 33.5%; P = 0.017); the rate with belimumab 1 mg/kg was 40.6% (P = 0.089). Week-76 response rates: 32.4%, 39.1%, and 38.5% with placebo, and belimumab 1 and 10 mg/kg, respectively. In post-hoc sensitivity analyses evaluating higher SELENA-SLEDAI thresholds, belimumab 10 mg/kg achieved better discrimination at weeks 52/76. Risk of severe SELENA-SLEDAI flares over 76 weeks was reduced with belimumab 1 mg/kg (34%; P = 0.023) and 10 mg/kg (23%; P = 0.13). Serious and severe adverse events including infections, laboratory abnormalities, malignancies, and deaths, were comparable across groups. Conclusion Belimumab plus SOC significantly improved SRI response rate, reduced SLE disease activity and severe flares, and was generally well-tolerated in SLE.

Objective To develop new classification criteria for systemic lupus erythematosus (SLE) jointly supported by the European League Against Rheumatism (EULAR) and the American College of Rheumatology (ACR). Methods This international initiative had four phases. 1) Evaluation of antinuclear antibody (ANA) as an entry criterion through systematic review and meta‐regression of the literature and criteria generation through an international Delphi exercise, an early patient cohort, and a patient survey. 2) Criteria reduction by Delphi and nominal group technique exercises. 3) Criteria definition and weighting based on criterion performance and on results of a multi‐criteria decision analysis. 4) Refinement of weights and threshold scores in a new derivation cohort of 1,001 subjects and validation compared with previous criteria in a new validation cohort of 1,270 subjects. Results The 2019 EULAR/ACR classification criteria for SLE include positive ANA at least once as obligatory entry criterion; followed by additive weighted criteria grouped in 7 clinical (constitutional, hematologic, neuropsychiatric, mucocutaneous, serosal, musculoskeletal, renal) and 3 immunologic (antiphospholipid antibodies, complement proteins, SLE‐specific antibodies) domains, and weighted from 2 to 10. Patients accumulating ≥10 points are classified. In the validation cohort, the new criteria had a sensitivity of 96.1% and specificity of 93.4%, compared with 82.8% sensitivity and 93.4% specificity of the ACR 1997 and 96.7% sensitivity and 83.7% specificity of the Systemic Lupus International Collaborating Clinics 2012 criteria. Conclusion These new classification criteria were developed using rigorous methodology with multidisciplinary and international input, and have excellent sensitivity and specificity. Use of ANA entry criterion, hierarchically clustered, and weighted criteria reflects current thinking about SLE and provides an improved foundation for SLE research.

Objective. To evaluate the efficacy and safety of rituximab in a randomized, double-blind, placebocontrolled phase III trial in patients with lupus nephritis treated concomitantly with mycophenolate mofetil (MMF) and corticosteroids.Methods. Patients (n ‫؍‬ 144) with class III or class IV lupus nephritis were randomized 1:1 to receive rituximab (1,000 mg) or placebo on days 1, 15, 168, and 182. The primary end point was renal response status at week 52.Results. Rituximab depleted peripheral CD19؉ B cells in 71 of 72 patients. The overall (complete and partial) renal response rates were 45.8% among the 72 patients receiving placebo and 56.9% among the 72 patients receiving rituximab (P ‫؍‬ 0.18); partial responses accounted for most of the difference. The primary end point (superior response rate with rituximab) was not achieved. Eight placebo-treated patients and no rituximab-treated patients required cyclophosphamide rescue therapy through week 52. Statistically significant improvements in serum complement C3, C4, and antidouble-stranded DNA (anti-dsDNA) levels were observed among patients treated with rituximab. In both treatment groups, a reduction in anti-dsDNA levels greater than the median reduction was associated with reduced proteinuria. The rates of serious adverse events, including infections, were similar in both groups. Neutropenia, leukopenia, and hypotension occurred more frequently in the rituximab group.Conclusion. Although rituximab therapy led to more responders and greater reductions in anti-dsDNA and C3/C4 levels, it did not improve clinical outcomes after 1 year of treatment. The combination of rituximab with MMF and corticosteroids did not result in any new or unexpected safety signals.Lupus nephritis (LN) may be observed in up to 50% of patients with systemic lupus erythematosus (SLE) and is associated with a poor prognosis (1). Although renal response rates among patients receiving standard treatment of proliferative LN may approach ClinicalTrials.gov identifier: NCT00282347.