Z. John Zhong

Efficacy and safety of belimumab in patients with active systemic lupus erythematosus: a randomised, placebo-controlled, phase 3 trial

BACKGROUND Systemic lupus erythematosus is a heterogeneous autoimmune disease that is associated with B-cell hyperactivity, autoantibodies, and increased concentrations of B-lymphocyte stimulator (BLyS). The efficacy and safety of the fully human monoclonal antibody belimumab (BLyS-specific inhibitor) was assessed in patients with active systemic lupus erythematosus. METHODS Patients (aged ≥18 years) who were seropositive with scores of at least 6 on the Safety of Estrogens in Lupus Erythematosus National Assessment-Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) were enrolled in a multicentre phase 3 study, which was done in Latin America, Asia-Pacific, and eastern Europe. Patients were randomly assigned by use of a central interactive voice response system in a 1:1:1 ratio to belimumab 1 mg/kg or 10 mg/kg, or placebo by intravenous infusion in 1 h on days 0, 14, and 28, and then every 28 days until 48 weeks, with standard of care. Patients, investigators, study coordinators, and sponsors were masked to treatment assignment. Primary efficacy endpoint was improvement in the Systemic Lupus Erythematosus Responder Index (SRI) at week 52 (reduction ≥4 points in SELENA-SLEDAI score; no new British Isles Lupus Assessment Group [BILAG] A organ domain score and no more than 1 new B organ domain score; and no worsening [<0·3 increase] in Physicians Global Assessment [PGA] score) versus baseline. Method of analysis was by modified intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00424476. FINDINGS 867 patients were randomly assigned to belimumab 1 mg/kg (n=289) or 10 mg/kg (n=290), or placebo (n=288). 865 were treated and analysed in the belimumab (1 mg/kg, n=288; 10 mg/kg, n=290) and placebo groups (n=287). Significantly higher SRI rates were noted with belimumab 1 mg/kg (148 [51%], odds ratio 1·55 [95% CI 1·10-2·19]; p=0·0129) and 10 mg/kg (167 [58%], 1·83 [1·30-2·59]; p=0·0006) than with placebo (125 [44%]) at week 52. More patients had their SELENA-SLEDAI score reduced by at least 4 points during 52 weeks with belimumab 1 mg/kg (153 [53%], 1·51 [1·07-2·14]; p=0·0189) and 10 mg/kg (169 [58%], 1·71 [1·21-2·41]; p=0·0024) than with placebo (132 [46%]). More patients given belimumab 1 mg/kg (226 [78%], 1·38 [0·93-2·04]; p=0·1064) and 10 mg/kg (236 [81%], 1·62 [1·09-2·42]; p=0·0181) had no new BILAG A or no more than 1 new B flare than did those in the placebo group (210 [73%]). No worsening in PGA score was noted in more patients with belimumab 1 mg/kg (227 [79%], 1·68 [1·15-2·47]; p=0·0078) and 10 mg/kg (231 [80%], 1·74 [1·18-2·55]; p=0·0048) than with placebo (199 [69%]). Rates of adverse events were similar in the groups given belimumab 1 mg/kg and 10 mg/kg, and placebo: serious infection was reported in 22 (8%), 13 (4%), and 17 (6%) patients, respectively, and severe or serious hypersensitivity reactions on an infusion day were reported in two (<1%), two (<1%), and no patients, respectively. No malignant diseases were reported. INTERPRETATION Belimumab has the potential to be the first targeted biological treatment that is approved specifically for systemic lupus erythematosus, providing a new option for the management of this important prototypic autoimmune disease. FUNDING Human Genome Sciences and GlaxoSmithKline.

A phase III, randomized, placebo-controlled study of belimumab, a monoclonal antibody that inhibits B lymphocyte stimulator, in patients with systemic lupus erythematosus.

OBJECTIVE To assess the efficacy/safety of the B lymphocyte stimulator inhibitor belimumab plus standard therapy compared with placebo plus standard therapy in active systemic lupus erythematosus (SLE). METHODS In a phase III, multicenter, randomized, placebo-controlled trial, 819 antinuclear antibody-positive or anti-double-stranded DNA-positive SLE patients with scores ≥6 on the Safety of Estrogens in Lupus Erythematosus National Assessment (SELENA) version of the SLE Disease Activity Index (SLEDAI) were randomized in a 1:1:1 ratio to receive 1 mg/kg belimumab, 10 mg/kg belimumab, or placebo intravenously on days 0, 14, and 28 and then every 28 days for 72 weeks. The primary efficacy end point was the SLE Responder Index (SRI) response rate at week 52 (an SRI response was defined as a ≥4-point reduction in SELENA-SLEDAI score, no new British Isles Lupus Assessment Group [BILAG] A organ domain score and no more than 1 new BILAG B score, and no worsening in physicians global assessment score versus baseline). RESULTS Belimumab at 10 mg/kg plus standard therapy met the primary efficacy end point, generating a significantly greater SRI response at week 52 compared with placebo (43.2% versus 33.5%; P = 0.017). The rate with 1 mg/kg belimumab was 40.6% (P = 0.089). Response rates at week 76 were 32.4%, 39.1%, and 38.5% with placebo, 1 mg/kg belimumab, and 10 mg/kg belimumab, respectively. In post hoc sensitivity analyses evaluating higher SELENA-SLEDAI score thresholds, 10 mg/kg belimumab achieved better discrimination at weeks 52 and 76. Risk of severe flares over 76 weeks (based on the modified SLE Flare Index) was reduced with 1 mg/kg belimumab (34%) (P = 0.023) and 10 mg/kg belimumab (23%) (P = 0.13). Serious and severe adverse events, including infections, laboratory abnormalities, malignancies, and deaths, were comparable across groups. CONCLUSION Belimumab plus standard therapy significantly improved SRI response rate, reduced SLE disease activity and severe flares, and was generally well tolerated in SLE.

A phase II, randomized, double-blind, placebo-controlled, dose-ranging study of belimumab in patients with active systemic lupus erythematosus.

OBJECTIVE To assess the safety, tolerability, biologic activity, and efficacy of belimumab in combination with standard of care therapy (SOC) in patients with active systemic lupus erythematosus (SLE). METHODS Patients with a Safety of Estrogens in Lupus Erythematosus: National Assessment (SELENA) version of the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score >/=4 (n = 449) were randomly assigned to belimumab (1, 4, or 10 mg/kg) or placebo in a 52-week study. Coprimary end points were the percent change in the SELENA-SLEDAI score at week 24 and the time to first SLE flare. RESULTS Significant differences between the treatment and placebo groups were not attained for either primary end point, and no dose response was observed. Reductions in SELENA-SLEDAI scores from baseline were 19.5% in the combined belimumab group versus 17.2% in the placebo group. The median time to first SLE flare was 67 days in the combined belimumab group versus 83 days in the placebo group. However, the median time to first SLE flare during weeks 24-52 was significantly longer with belimumab treatment (154 versus 108 days; P = 0.0361). In the subgroup (71.5%) of serologically active patients (antinuclear antibody titer >/=1:80 and/or anti-double-stranded DNA [anti-dsDNA] >/=30 IU/ml), belimumab treatment resulted in significantly better responses at week 52 than placebo for SELENA-SLEDAI score (-28.8% versus -14.2%; P = 0.0435), physicians global assessment (-32.7% versus -10.7%; P = 0.0011), and Short Form 36 physical component score (+3.0 versus +1.2 points; P = 0.0410). Treatment with belimumab resulted in a 63-71% reduction of naive, activated, and plasmacytoid CD20+ B cells, and a 29.4% reduction in anti-dsDNA titers (P = 0.0017) by week 52. The rates of adverse events and serious adverse events were similar in the belimumab and placebo groups. CONCLUSION Belimumab was biologically active and well tolerated. The effect of belimumab on the reduction of SLE disease activity or flares was not significant. However, serologically active SLE patients responded significantly better to belimumab therapy plus SOC than to SOC alone.

Novel evidence-based systemic lupus erythematosus responder index

OBJECTIVE To describe a new systemic lupus erythematosus (SLE) responder index (SRI) based on a belimumab phase II SLE trial and demonstrate its potential utility in SLE clinical trials. METHODS Data from a randomized, double-blind, placebo-controlled study in 449 patients of 3 doses of belimumab (1, 4, 10 mg/kg) or placebo plus standard of care therapy (SOC) over a 56-week period were analyzed. The Safety of Estrogens in Lupus Erythematosus: National Assessment (SELENA) version of the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and British Isles Lupus Assessment Group (BILAG) SLE disease activity instruments, the Short Form 36 health survey, and biomarker analyses were used to create a novel SRI. Response to treatment in a subset of 321 serologically active SLE patients (antinuclear antibodies >/=1:80 and/or anti-double-stranded DNA antibodies >/=30 IU/ml) at baseline was retrospectively evaluated using the SRI. RESULTS SRI response is defined as 1) a >/=4-point reduction in SELENA-SLEDAI score, 2) no new BILAG A or no more than 1 new BILAG B domain score, and 3) no deterioration from baseline in the physicians global assessment by >/=0.3 points. In serologically active patients, the addition of belimumab to SOC resulted in a response in 46% of patients at week 52 compared with 29% of the placebo patients (P = 0.006). SRI responses were independent of baseline autoantibody subtype. CONCLUSION This evidence-based evaluation of a large randomized, placebo-controlled trial in SLE resulted in the ability to define a robust responder index based on improvement in disease activity without worsening the overall condition or the development of significant disease activity in new organ systems.

Effects of belimumab, a B lymphocyte stimulator-specific inhibitor, on disease activity across multiple organ domains in patients with systemic lupus erythematosus: combined results from two phase III trials

Objective To evaluate the effects of belimumab versus placebo, plus standard systemic lupus erythematosus (SLE) therapy, on organ domain-specific SLE disease activity. Methods Data obtained after 52 weeks of treatment from two phase III trials (BLISS-52 and BLISS-76) comparing belimumab 1 and 10 mg/kg versus placebo, plus standard therapy, in 1684 autoantibody-positive patients were analysed post hoc for changes in British Isles Lupus Assessment Group (BILAG) and Safety of Estrogens in Lupus National Assessment–Systemic Lupus Erythematosus Disease Activity Index (SELENA–SLEDAI) organ domain scores. Results At baseline, the domains involved in the majority of patients were musculoskeletal and mucocutaneous by both BILAG and SELENA–SLEDAI, and immunological by SELENA–SLEDAI. At 52 weeks, significantly more patients treated with belimumab versus placebo had improvement in BILAG musculoskeletal and mucocutaneous domains (1 and 10 mg/kg), and in SELENA–SLEDAI mucocutaneous (10 mg/kg), musculoskeletal (1 mg/kg) and immunological (1 and 10 mg/kg) domains. Improvement was also observed in other organ systems with a low prevalence (≤16%) at baseline, including the SELENA–SLEDAI vasculitis and central nervous system domains. Significantly fewer patients treated with belimumab versus placebo had worsening in the BILAG haematological domain (1 mg/kg) and in the SELENA–SLEDAI immunological (10 mg/kg), haematological (10 mg/kg) and renal (1 mg/kg) domains. Conclusions Belimumab treatment improved overall SLE disease activity in the most common musculoskeletal and mucocutaneous organ domains. Less worsening occurred in the haematological, immunological and renal domains.

Belimumab in the treatment of systemic lupus erythematosus: high disease activity predictors of response

Objectives To identify factors that predict response to belimumab treatment in the phase 3 BLISS trials of autoantibody-positive systemic lupus erythematosus (SLE) and further analyse clinical efficacy in various patient subsets. Methods The BLISS trials compared belimumab 1 and 10 mg/kg versus placebo, all plus standard SLE therapy, over 52 or 76 weeks. Pooled subgroup analyses of week 52 SLE responder index rates (the primary endpoint in both trials) were performed based on demographic characteristics and baseline disease activity indicators. Pooled multivariate analysis was performed to determine predictors of response and treatment effect. Results Pooled univariate and multivariate analyses (N=1684) identified baseline factors associated with an increased benefit of belimumab versus placebo. These factors included the Safety Of Estrogens In Lupus Erythematosus National Assessment–Systemic Lupus Erythematosus Disease Activity Index (SELENA–SLEDAI) ≥10, low complement, anti-dsDNA positivity and corticosteroid use. Efficacy outcomes were assessed in the low complement/anti-dsDNA-positive and SELENA–SLEDAI ≥10 subgroups. Week 52 SLE Responder Index rates in the low complement/anti-dsDNA-positive subgroup were 31.7%, 41.5% (p=0.002) and 51.5% (p<0.001) with placebo and belimumab 1 mg/kg and 10 mg/kg, respectively; corresponding rates in the SELENA–SLEDAI ≥10 subgroup were 44.3%, 58.0% (p<0.001) and 63.2% (p<0.001). Further analysis of secondary endpoints in the low complement/anti-dsDNA-positive subgroup showed that compared with placebo, belimumab produced greater benefits regarding severe flares, corticosteroid use and health-related quality of life. Conclusions These findings suggest that belimumab has greater therapeutic benefit than standard therapy alone in patients with higher disease activity, anti-dsDNA positivity, low complement or corticosteroid treatment at baseline. ClinicalTrials.gov identifiers NCT00424476 and NCT00410384

Belimumab reduces autoantibodies, normalizes low complement levels, and reduces select B cell populations in patients with systemic lupus erythematosus

OBJECTIVE To assess the effects of the B lymphocyte stimulator (BLyS)-specific inhibitor belimumab on immunologic biomarkers, including B cell and T cell populations, and maintenance of antibody titers to prior vaccines in autoantibody-positive systemic lupus erythematosus (SLE) patients. METHODS Pooled data from 2 phase III trials, the Study of Belimumab in Subjects with SLE 52-week (BLISS-52) and 76-week (BLISS-76) trials, comparing belimumab 1 mg/kg or 10 mg/kg versus placebo (plus standard SLE therapy for each group) were analyzed for changes in autoantibody, immunoglobulin, and complement levels. BLISS-76 patients were also analyzed for changes in B cell and T cell populations and effects on prior vaccine-induced antibody levels. RESULTS Belimumab-treated patients experienced significant sustained reductions in IgG and autoantibodies and improvement in C3/C4 levels, resulting in greater positive-to-negative conversion rates for IgG anti-double-stranded DNA (anti-dsDNA), anti-Sm, anticardiolipin, and anti-ribosomal P autoantibodies and normalization of hypergammaglobulinemia and low C3/C4 levels. Belimumab-treated patients experienced significant decreases in the numbers of naive and activated B cells, as well as plasma cells, whereas memory B cells and T cell populations did not decrease. Belimumab did not substantially affect preexisting antipneumococcal or anti-tetanus toxoid antibody levels. Post hoc analysis showed greater reductions in SLE disease activity and the risk of severe flares in patients treated with belimumab 10 mg/kg (P≤0.01) who were anti-dsDNA positive and had low C3/C4 levels at baseline. Normalization of the C3 or anti-dsDNA level by 8 weeks, irrespective of therapy, was predictive of a reduced risk of severe flare over 52 weeks. CONCLUSION Belimumab appears to promote normalization of serologic activity and reduce BLyS-dependent B cell subsets in serologically and clinically active SLE. Greater serologic activity may predict a better treatment response to belimumab.

Disease control and safety of belimumab plus standard therapy over 7 years in patients with systemic lupus erythematosus.

Objective. To evaluate the efficacy/safety of belimumab plus standard therapy in patients (n = 449) with active systemic lupus erythematosus (SLE) treated up to 7 years (n = 177 currently ongoing). Methods. Patients (n = 345) who completed a double-blind, placebo-controlled, 52-week study of belimumab 1, 4, or 10 mg/kg and 24-week extension of belimumab (placebo switched to 10 mg/kg; belimumab same dose or switched to 10 mg/kg) could receive belimumab 10 mg/kg in an open-label continuation study (n = 296). Disease activity was analyzed in patients with active SLE at baseline of the initial study. Biomarker and SLE medication changes were evaluated, and adverse events (AE) were monitored throughout the study. Results. Total belimumab exposure over 7 years (double-blind and open-label periods): 1746 patient-years. SLE Responder Index (SRI) response rates at Week 52 in autoantibody-positive patients: placebo, 29%; belimumab, 46% (p < 0.05). In the continuation study, 57% of auto-antibody-positive patients had an SRI response by Year 2 and 65% by Year 7; severe flares occurred in 19% with placebo and 17% with belimumab during the first year, with the annual rate declining to 2%–9% during years 2–7. Anti-dsDNA autoantibodies in patients positive for them at baseline had a progressive decline of 40%–60% from baseline over 2–7 years with belimumab. Corticosteroid use decreased over time with ≥ 50–55% reduction in median dose during years 5–7. Serious and overall annual AE rates, including infections, were generally stable or decreased during 7-year treatment. Conclusion. Disease control and safety profile were maintained in patients with active SLE taking belimumab plus standard therapy for up to 7 years. [ClinicalTrials.gov numbers: NCT00071487 and NCT00583362]

Long‐term safety profile of belimumab plus standard therapy in patients with systemic lupus erythematosus

OBJECTIVE To evaluate the safety profile of long-term belimumab therapy combined with standard therapy for systemic lupus erythematosus (SLE) in patients with active disease. METHODS Patients who were randomized to receive intravenous placebo or belimumab 1, 4, or 10 mg/kg, plus standard therapy, and completed the initial 52-week double-blind treatment period were then allowed to enter a 24-week open-label extension phase. During the extension period, patients in the belimumab group either received the same dose or were switched to 10 mg/kg and patients in the placebo group were switched to belimumab 10 mg/kg. Patients who achieved a satisfactory response during the 24-week extension period were allowed to participate in the long-term continuation study of monthly belimumab 10 mg/kg. Adverse events (AEs) and abnormal laboratory results were analyzed per 100 patient-years in 1-year intervals. RESULTS Of the 364 patients who completed the 52-week double-blind treatment period, 345 entered the 24-week extension, and 296 continued treatment with belimumab in the long-term continuation study. Safety data through 4 years of belimumab exposure (1,165 cumulative patient-years) are reported. Incidence rates of AEs, severe/serious AEs, infusion reactions, infections, malignancies, grades 3/4 laboratory abnormalities, and discontinuations due to AEs were stable or declined during 4-year belimumab exposure. The most common AEs included arthralgia, upper respiratory tract infection, headache, fatigue, and nausea. Serious infusion reactions were rare: only 1 occurred during the 4-year followup period. Rates of serious infection decreased from 5.9/100 patient-years to 3.4/100 patient-years, and no specific type of infection predominated. CONCLUSION Belimumab added to standard therapy was generally well-tolerated over the 4-year treatment period in patients with SLE, which suggests that belimumab can be administered long term with an acceptable safety profile.

Baseline Predictors of Systemic Lupus Erythematosus Flares: Data From the Combined Placebo Groups in the Phase III Belimumab Trials

OBJECTIVE To identify predictors of moderate-to-severe systemic lupus erythematosus (SLE) flare in 562 patients treated with standard therapy alone in phase III belimumab trials, and to evaluate the impact of standard therapies on preventing flares. METHODS Post hoc analysis assessed baseline demographics, disease activity, and biomarkers in patients with and those without flare at treatment weeks 24 and 52. Severe flare was defined by the modified SLE Flare Index (SFI) and the development of any new British Isles Lupus Assessment Group (BILAG) A domain score. Severe and moderate flare was defined by development of 1 new BILAG A domain score or 2 new BILAG B domain scores. Baseline characteristics associated with a ≥10% absolute difference or a ≥50% increase in flare rates were considered predictive. RESULTS Frequencies of flares over 52 weeks according to the SFI, any new BILAG A domain score, and 1 new BILAG A domain score or 2 new BILAG B domain scores were 23.7%, 23.1%, and 32.0%, respectively. Flare predictors by univariate analysis on all 3 indices at weeks 24 and 52 were a score ≥12 on the Safety of Estrogens in Lupus Erythematosus National Assessment version of the SLE Disease Activity Index (SELENA-SLEDAI); anti-double-stranded DNA (anti-dsDNA) positivity; proteinuria (≥0.5 gm/24 hours); BILAG renal, vasculitic, and hematologic scores; elevated C-reactive protein levels; and B lymphocyte stimulator (BLyS) levels ≥2 ng/ml. Independent predictors by multivariate analysis at week 52 were SELENA-SLEDAI and/or BILAG renal involvement and anti-dsDNA ≥200 IU/ml (on all 3 indices); SELENA-SLEDAI and/or BILAG neurologic and vasculitic involvement (on 2 indices: any new BILAG A domain score and 1 new BILAG A domain score or 2 new BILAG B domain scores); BLyS levels ≥2 ng/ml (on 2 indices: the SFI and 1 new BILAG A domain score or 2 new BILAG B domain scores); and low C3 level (on the SFI). Baseline medications did not significantly decrease or increase moderate-to-severe SLE flare risk. CONCLUSION Patients who were receiving standard SLE therapy and had renal, neurologic, or vasculitic involvement, elevated anti-dsDNA or BLyS levels, or low C3 had increased risk of clinically meaningful flare over 1 year. Hydroxychloroquine use was not predictive.