Introduction

The purpose of this study was to quantitatively evaluate the contribution of synovial lymphoid aggregates to autoantibody (rheumatoid factor [RF] and anti-cyclic citrullinated peptide [anti-CCP]) and total immunoglobulin (IgG and IgM) production in rheumatoid arthritis (RA) patients and the effect thereon of the B-cell-depleting antibody, rituximab, in the ARISE (Assessment of Rituximab's Immunomodulatory Synovial Effects) trial.

Methods

Autoantibodies as well as total IgM and IgG were quantified by enzyme-linked immunosorbent assay in extracts of synovial tissues and matched serum from patients with RA or osteoarthritis (OA). Synovial biopsies and serum were obtained at baseline and 8 weeks following rituximab therapy in 14 RA patients. A synovial/serum index (SSI) was calculated as the ratio of synovial to serum antibody/albumin, with values above 1 representing synovial enrichment. Lymphoid aggregates were evaluated histologically.

Results

Anti-CCP IgG, but not RF-IgM, was significantly enriched in RA synovia compared with serum. Total IgM and IgG were also enriched in RA, but not in OA. SSI correlated significantly with mRNA content for both IgM and IgG, demonstrating that it reflected synovial immunoglobulin production. RA synovia with lymphocyte aggregates contained significantly elevated RF-IgM and anti-CCP IgG compared with tissues with diffuse lymphoid infiltration. Rituximab treatment did not affect synovial autoantibody or total immunoglobulin SSI overall. However, in aggregate-containing tissues, rituximab significantly reduced total IgM and IgG SSI as well as IgM and IgG1 mRNA. Surprisingly, RF-IgM and anti-CCP IgG SSIs were unchanged by rituximab in aggregate-containing synovia.

Conclusions

Combined with earlier observations that synovial lymphoid aggregates are unaltered by rituximab treatment, these data suggest that lymphoid aggregates may provide a protective niche for autoantibody-producing cells.

BACKGROUND:Targeted inhibitors of B-cell activating factor (BAFF) have been evaluated in phase III trials in over 4000 patients with systemic lupus erythematosus (SLE). Post hoc analyses of these studies identify greater treatment effect in patients entering with higher disease activity, greater corticosteroid doses, anti double-stranded DNA (dsDNA) and low complement C3 or C4. OBJECTIVES:To evaluate the efficacy and safety of blisibimod, a BAFF inhibitor, in a population of patients with SLE enriched for high disease activity. METHODS:442 patients with SLE with antinuclear antibodies or anti-dsDNA and Safety of Estrogen in Lupus Erythematosus National Assessment - Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) score ≥10 on standard-of-care medications were randomised to receive weekly subcutaneous blisibimod (200 mg) or placebo. Corticosteroid taper was encouraged from week 8. The primary end point was the week 52 SLE Responder Index-6 (SRI-6). RESULTS:The SRI-6 primary end point was not met. There was a statistically significant steroid-sparing effect, and significantly more blisibimod-treated subjects achieved corticosteroid taper. Increased blisibimod treatment effect on SRI-6 was observed in subjects who achieved a concomitant decrease in corticosteroid dose from baseline. In subjects with baseline urinary protein:creatinine ratio (UPCR) ≥56.5 mg/mmol, significantly higher proportions of blisibimod subjects achieved >50% reduction in UPCR and/or UPCR <56.5 mg/mmol. Reductions in SLE autoantibodies and B cells, and increases in complement C3 and C4 were observed with blisibimod.Blisibimod was well-tolerated. The most common adverse events were upper respiratory tract infection, urinary tract infection, injection site erythema/reaction and diarrhoea. CONCLUSIONS:Although the SRI-6 end point was not met, blisibimod was associated with successful steroid reduction, decreased proteinuria and biomarker responses. TRIAL REGISTRATION NUMBER:NCT01395745.

Objective

To explore long-term safety and tolerability of anifrolumab 300 mg compared with placebo in patients with systemic lupus erythematosus (SLE) who completed a Treatment of Uncontrolled Lupus via the Interferon Pathway (TULIP) trial and enrolled in the placebo-controlled 3-year long-term extension (LTE) study (ClinicalTrials.gov identifier: NCT02794285).

Methods

In the blinded LTE study, patients continued anifrolumab 300 mg, switched from anifrolumab 150 mg to 300 mg, or were re-randomized from placebo to receive either anifrolumab 300 mg or to continue placebo, administered every 4 weeks. Primary comparisons in the LTE study were between patients who received anifrolumab 300 mg or placebo throughout the TULIP and LTE studies. For rare safety events, comparisons included patients who received any anifrolumab dose during TULIP or LTE. When exposure differed, exposure-adjusted incidence rates (EAIRs) per 100 patient-years were calculated.

Results

In the LTE study, EAIRs of serious adverse events (SAEs) were 8.5 with anifrolumab compared with 11.2 with placebo; likewise, EAIRs of AEs leading to treatment discontinuation were 2.5 versus 3.2, respectively. EAIRs of non-opportunistic serious infections were comparable between groups (3.7 with anifrolumab versus 3.6 with placebo). Exposure-adjusted event rates of COVID-related AEs, including asymptomatic infections, were 15.5 with anifrolumab compared with 9.8 with placebo. No COVID-related AEs occurred in fully vaccinated individuals. EAIRs of malignancy and major acute cardiovascular events were low and comparable between groups. Anifrolumab was associated with lower cumulative glucocorticoid use and greater mean improvement in the SLE Disease Activity Index 2000, compared with placebo.

Conclusion

This LTE study represents the longest placebo-controlled clinical trial performed in SLE to date. No new safety findings were identified in the LTE study, supporting the favorable benefit-risk profile of anifrolumab for patients with moderate-to-severe SLE receiving standard therapy.

Objectives

To characterise the efficacy and safety of anifrolumab in patients with systemic lupus erythematosus (SLE) according to interferon gene signature (IFNGS), demographic and clinical subgroups.

Methods

We performed post hoc analyses of pooled data from the 52-week phase III TULIP-1/TULIP-2 placebo-controlled trials of intravenous anifrolumab in moderate-to-severe SLE. Outcomes were assessed in predefined subgroups: IFNGS (high/low), age, sex, body mass index, race, geographic region, age of onset, glucocorticoid use, disease activity and serological markers.

Results

In pooled data, patients received anifrolumab 300 mg (360/726) or placebo (366/726); 82.6% were IFNGS-high. IFNGS-high patients had greater baseline disease activity and were more likely to have abnormal serological markers versus IFNGS-low patients. In the total population, a greater proportion of patients treated with anifrolumab versus placebo achieved British Isles Lupus Assessment Group-based Composite Lupus Assessment (BICLA) response at week 52 (difference 16.6%; nominal p<0.001). BICLA response treatment differences with anifrolumab versus placebo were comparable to the total population across most predefined subgroups, including subgroups for baseline glucocorticoid dosage (<10/≥10 mg/day prednisone/equivalent) and for clinical disease activity (SLE Disease Activity Index 2000 score <10/≥10). Subgroups with larger treatment differences included IFNGS-high patients (18.2%), patients with abnormal baseline serological markers (23.1%) and Asian patients (29.2%). The safety profile of anifrolumab was similar across subgroups.

Conclusions

Overall, this study supports the consistent efficacy and safety of anifrolumab across a range of patients with moderate-to-severe SLE. In a few subgroups, small sample sizes limited conclusions from being drawn regarding the treatment benefit with anifrolumab.

Trial registration number

NCT02446912, NCT02446899.

Objective

To evaluate the frequency of cell-bound complement activation products (CB-CAPs) as a marker of complement activation in patients with suspected systemic lupus erythematosus (SLE) and the usefulness of this biomarker as a predictor of the evolution of probable SLE into SLE as classified by the American College of Rheumatology (ACR) criteria.

Methods

Patients in whom SLE was suspected by lupus experts and who fulfilled 3 ACR classification criteria for SLE (probable SLE) were enrolled, along with patients with established SLE as classified by both the ACR and the Systemic Lupus International Collaborating Clinics (SLICC) criteria, patients with primary Sjögren's syndrome (SS), and patients with other rheumatic diseases. Individual CB-CAPs were measured by flow cytometry, and positivity rates were compared to those of commonly assessed biomarkers, including serum complement proteins (C3 and C4) and autoantibodies. The frequency of a positive multianalyte assay panel (MAP), which includes CB-CAPs, was also evaluated. Probable SLE cases were followed up prospectively.

Results

The 92 patients with probable SLE were diagnosed more recently than the 53 patients with established SLE, and their use of antirheumatic medications was lower. At the enrollment visit, more patients with probable SLE were positive for CB-CAPs (28%) or MAP (40%) than had low complement levels (9%) (P = 0.0001 for each). In probable SLE, MAP scores of >0.8 at enrollment predicted fulfillment of a fourth ACR criterion within 18 months (hazard ratio 3.11, P < 0.01).

Conclusion

Complement activation occurs in some patients with probable SLE and can be detected with higher frequency by evaluating CB-CAPs and MAP than by assessing traditional serum complement protein levels. A MAP score above 0.8 predicts transition to classifiable SLE according to ACR criteria.

Objectives

In the anifrolumab systemic lupus erythematosus (SLE) trial programme, there was one trial (TULIP-1) in which BILAG-based Composite Lupus Assessment (BICLA) responses favoured anifrolumab over placebo, but the SLE Responder Index (SRI(4)) treatment difference was not significant. We investigated the degree of concordance between BICLA and SRI(4) across anifrolumab trials in order to better understand drivers of discrepant SLE trial results.

Methods

TULIP-1, TULIP-2 (both phase 3) and MUSE (phase 2b) were randomised, 52-week trials of intravenous anifrolumab (300 mg every 4 weeks, 48 weeks; TULIP-1/TULIP-2: n=180; MUSE: n=99) or placebo (TULIP-1: n=184, TULIP-2: n=182; MUSE: n=102). Week 52 BICLA and SRI(4) outcomes were assessed for each patient.

Results

Most patients (78%-85%) had concordant BICLA and SRI(4) outcomes (Cohen's Kappa 0.6-0.7, nominal p<0.001). Dual BICLA/SRI(4) response rates favoured anifrolumab over placebo in TULIP-1, TULIP-2 and MUSE (all nominal p≤0.004). A discordant TULIP-1 BICLA non-responder/SRI(4) responder subgroup was identified (40/364, 11% of TULIP-1 population), comprising more patients receiving placebo (n=28) than anifrolumab (n=12). In this subgroup, placebo-treated patients had lower baseline disease activity, joint counts and glucocorticoid tapering rates, and more placebo-treated patients had arthritis response than anifrolumab-treated patients.

Conclusions

Across trials, most patients had concordant BICLA/SRI(4) outcomes and dual BICLA/SRI(4) responses favoured anifrolumab. A BICLA non-responder/SRI(4) responder subgroup was identified where imbalances of key factors driving the BICLA/SRI(4) discordance (disease activity, glucocorticoid taper) disproportionately favoured the TULIP-1 placebo group. Careful attention to baseline disease activity and monitoring glucocorticoid taper variation will be essential in future SLE trials.

Trial registration numbers

NCT02446912 and NCT02446899.

Objective

To evaluate the usefulness of biomarkers to predict the evolution of patients suspected of systemic lupus erythematosus (SLE), designated as probable SLE (pSLE), into classifiable SLE according to the American College of Rheumatology (ACR) classification criteria.

Methods

Patients suspected of SLE were enrolled by lupus experts if they fulfilled three ACR criteria for SLE and were followed for approximately 1-3 years to evaluate transition into ACR-classifiable SLE. Individual cell-bound complement activation products (CB-CAPs), serum complement proteins (C3 and C4), and autoantibodies were measured by flow cytometry, turbidimetry, and enzyme-linked immunosorbent assay, respectively. Blood levels of hydroxychloroquine (HCQ) were measured by mass spectrometry. A multianalyte assay panel (MAP), which includes CB-CAPs, was also evaluated. A MAP of greater than 0.8 reflected the optimal cutoff for transition to SLE. Time to fulfillment of ACR criteria was evaluated by Kaplan-Meier analysis and Cox proportional hazards model.

Results

Of the 92 patients with pSLE enrolled, 74 had one or two follow-up visits 9-35 months after enrollment for a total of 128 follow-up visits. Overall, 28 patients with pSLE (30.4%) transitioned to ACR-classifiable SLE, including 16 (57%) in the first year and 12 (43%) afterwards. A MAP score of greater than 0.8 at enrollment predicted transition to classifiable SLE during the follow-up period (hazard ratio = 2.72; P = 0.012), whereas individual biomarkers or fulfillment of Systemic Lupus International Collaborating Clinics criteria did not. HCQ therapy was not associated with the prevention of transition to SLE.

Conclusion

Approximately one-third of patients with pSLE transitioned within the study period. MAP of greater than 0.8 predicted disease evolution into classifiable SLE.

Objective

Evaluate the efficacy and safety of ustekinumab, an anti-interleukin-12/23 p40 antibody, in a phase 3, randomised, placebo-controlled study of patients with active systemic lupus erythematosus (SLE) despite receiving standard-of-care.

Methods

Active SLE patients (SLE Disease Activity Index 2000 (SLEDAI-2K) ≥6 during screening and SLEDAI-2K ≥4 for clinical features at week 0) despite receiving oral glucocorticoids, antimalarials, or immunomodulatory drugs were randomised (3:2) to receive ustekinumab (intravenous infusion ~6 mg/kg at week 0, followed by subcutaneous injections of ustekinumab 90 mg at week 8 and every 8 weeks) or placebo through week 48. The primary endpoint was SLE Responder Index (SRI)-4 at week 52, and major secondary endpoints included time to flare through week 52 and SRI-4 at week 24.

Results

At baseline, 516 patients were randomised to placebo (n=208) or ustekinumab (n=308). Following the planned interim analysis, the sponsor discontinued the study due to lack of efficacy but no safety concerns. Efficacy analyses included 289 patients (placebo, n=116; ustekinumab, n=173) who completed or would have had a week 52 visit at study discontinuation. At week 52, 44% of ustekinumab patients and 56% of placebo patients had an SRI-4 response; there were no appreciable differences between the treatment groups in the major secondary endpoints. Through week 52, 28% of ustekinumab patients and 32% of placebo patients had a British Isles Lupus Assessment Group flare, with a mean time to first flare of 204.7 and 200.4 days, respectively. Through week 52, 70% of ustekinumab patients and 74% of placebo patients had ≥1 adverse event.

Conclusions

Ustekinumab did not demonstrate superiority over placebo in this population of adults with active SLE; adverse events were consistent with the known safety profile of ustekinumab.

Trial registration number

NCT03517722.

To evaluate the association between lupus severity and cell-bound complement activation products (CB-CAPs) or low complement proteins C3 and C4. All subjects (n=495) fulfilled the American College of Rheumatology (ACR) classification criteria for SLE. Abnormal CB-CAPs (erythrocyte-bound C4d or B-lymphocyte-bound C4d levels >99th percentile of healthy) and complement proteins C3 and C4 were determined using flow cytometry and turbidimetry, respectively. Lupus severity was estimated using the Lupus Severity Index (LSI). Statistical analysis consisted of multivariable linear regression and groups comparisons. Abnormal CB-CAPs were more prevalent than low complement values irrespective of LSI levels (62% vs 38%, respectively, p<0.0001). LSI was low (median 5.44, IQR: 4.77-6.93) in patients with no complement abnormality, intermediate in patients with abnormal CB-CAPs (median 6.09, IQR: 5.31-8.20) and high in the group presenting with both abnormal CB-CAPs and low C3 and/or C4 (median 7.85, IQR: 5.51-8.37). Odds of immunosuppressant use was higher in subjects with LSI ≥5.95 compared with subjects with LSI <5.95 (1.60 vs 0.53, p<0.0001 for both). Multivariable regression analysis revealed that higher LSI scores associated with abnormal CB-CAPs-but not low C3/C4-after adjusting for younger age, race and longer disease duration (p=0.0001), which were also independent predictors of disease severity (global R2=0.145). Abnormalities in complement activation as measured by CB-CAPs are associated with increased LSI.

Objective

To study bidirectional change and predictors of change in estimated glomerular filtration rate (GFR) and proteinuria in lupus nephritis (LN) using a multistate modeling approach.

Methods

Patients in the Systemic Lupus International Collaborating Clinics inception cohort were classified annually into estimated GFR state 1 (>60 ml/minute), state 2 (30-60 ml/minute), or state 3 (<30 ml/minute) and estimated proteinuria state 1 (<0.25 gm/day), state 2 (0.25-3.0 gm/day), or state 3 (>3.0 gm/day), or end-stage renal disease (ESRD) or death. Using multistate modeling, relative transition rates between states indicated improvement and deterioration.

Results

Of 1,826 lupus patients, 700 (38.3%) developed LN. During a mean ± SD follow-up of 5.2 ± 3.5 years, the likelihood of improvement in estimated GFR and estimated proteinuria was greater than the likelihood of deterioration. After 5 years, 62% of patients initially in estimated GFR state 3 and 11% of patients initially in estimated proteinuria state 3 transitioned to ESRD. The probability of remaining in the initial states 1, 2, and 3 was 85%, 11%, and 3%, respectively, for estimated GFR and 62%, 29%, and 4%, respectively, for estimated proteinuria. Male sex predicted improvement in estimated GFR states; older age, race/ethnicity, higher estimated proteinuria state, and higher renal biopsy chronicity scores predicted deterioration. For estimated proteinuria, race/ethnicity, earlier calendar years, damage scores without renal variables, and higher renal biopsy chronicity scores predicted deterioration; male sex, presence of lupus anticoagulant, class V nephritis, and mycophenolic acid use predicted less improvement.

Conclusion

In LN, the expected improvement or deterioration in renal outcomes can be estimated by multistate modeling and is preceded by identifiable risk factors. New therapeutic interventions for LN should meet or exceed these expectations.