Andreas Schwarting

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 physician's 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.

OBJECTIVE: To assess the efficacy and safety of subcutaneous (SC) belimumab in patients with systemic lupus erythematosus (SLE). METHODS: Patients with moderate-to-severe SLE (score of ≥8 on the Safety of Estrogens in Lupus Erythematosus National Assessment [SELENA] version of the SLE Disease Activity Index [SLEDAI]) were randomized 2:1 to receive weekly SC belimumab 200 mg or placebo by prefilled syringe in addition to standard SLE therapy for 52 weeks. The primary end point was the SLE Responder Index (SRI4) at week 52. Secondary end points were reduction in the corticosteroid dosage and time to severe flare. Safety was assessed according to the adverse events (AEs) reported and the laboratory test results. RESULTS: Of 839 patients randomized, 836 (556 in the belimumab group and 280 in the placebo group) received treatment. A total of 159 patients withdrew before the end of the study. At entry, mean SELENA-SLEDAI scores were 10.5 in the belimumab group and 10.3 in the placebo group. More patients who received belimumab were SRI4 responders than those who received placebo (61.4% versus 48.4%; odds ratio [OR] 1.68 [95% confidence interval (95% CI) 1.25-2.25]; P = 0.0006). In the belimumab group, both time to and risk of severe flare were improved (median 171.0 days versus 118.0 days; hazard ratio 0.51 [95% CI 0.35-0.74]; P = 0.0004), and more patients were able to reduce their corticosteroid dosage by ≥25% (to ≤7.5 mg/day) during weeks 40-52 (18.2% versus 11.9%; OR 1.65 [95% CI 0.95-2.84]; P = 0.0732), compared with placebo. AE incidence was comparable between treatment groups; serious AEs were reported by 10.8% of patients taking belimumab and 15.7% of those taking placebo. A worsening of IgG hypoglobulinemia by ≥2 grades occurred in 0.9% of patients taking belimumab and 1.4% of those taking placebo. CONCLUSION: In patients with moderate-to-severe SLE, weekly SC doses of belimumab 200 mg plus standard SLE therapy significantly improved their SRI4 response, decreased severe disease flares as compared with placebo, and had a safety profile similar to placebo plus standard SLE therapy.

Infiltrating leukocytes may be responsible for autoimmune disease. We hypothesized that the chemokine monocyte chemoattractant protein (MCP)-1 recruits macrophages and T cells into tissues that, in turn, are required for autoimmune disease. Using the MRL-Fas(lpr) strain with spontaneous, fatal autoimmune disease, we constructed MCP-1-deficient MRL-Fas(lpr) mice. In MCP-1-intact MRL-Fas(lpr) mice, macrophages and T cells accumulate at sites (kidney tubules, glomeruli, pulmonary bronchioli, lymph nodes) in proportion to MCP-1 expression. Deleting MCP-1 dramatically reduces macrophage and T cell recruitment but not proliferation, protects from kidney, lung, skin, and lymph node pathology, reduces proteinuria, and prolongs survival. Notably, serum immunoglobulin (Ig) isotypes and kidney Ig/C3 deposits are not diminished in MCP-1-deficient MRL-Fas(lpr) mice, highlighting the requirement for MCP-1-dependent leukocyte recruitment to initiate autoimmune disease. However, MCP-1-deficient mice are not completely protected from leukocytic invasion. T cells surrounding vessels with meager MCP-1 expression remain. In addition, downstream effector cytokines/chemokines are decreased in MCP-1-deficient mice, perhaps reflecting a reduction of cytokine-expressing leukocytes. Thus, MCP-1 promotes MRL-Fas(lpr) autoimmune disease through macrophage and T cell recruitment, amplified by increasing local cytokines/chemokines. We suggest that MCP-1 is a principal therapeutic target with which to combat autoimmune diseases.

Monocyte chemoattractant protein-1 (MCP-1) is upregulated in renal parenchymal cells during kidney disease. To investigate whether MCP-1 promotes tubular and/or glomerular injury, we induced nephrotoxic serum nephritis (NSN) in MCP-1 genetically deficient mice. Mice were analyzed when tubules and glomeruli were severely damaged in the MCP-1-intact strain (day 7). MCP-1 transcripts increased fivefold in MCP-1-intact mice. MCP-1 was predominantly localized within cortical tubules (90%), and most cortical tubules were damaged, whereas few glomerular cells expressed MCP-1 (10%). By comparison, there was a marked reduction (>40%) in tubular injury in MCP-1-deficient mice (histopathology, apoptosis). MCP-1-deficient mice were not protected from glomerular injury (histopathology, proteinuria, macrophage influx). Macrophage accumulation increased adjacent to tubules in MCP-1-intact mice compared with MCP-1-deficient mice (70%, P < 0.005), indicating that macrophages recruited by MCP-1 induce tubular epithelial cell (TEC) damage. Lipopolysaccharide-activated bone marrow macrophages released molecules that induced TEC death that was not dependent on MCP-1 expression by macrophages or TEC. In conclusion, MCP-1 is predominantly expressed by TEC and not glomeruli, promotes TEC and not glomerular damage, and increases activated macrophages adjacent to TEC that damage TEC during NSN. Therefore, we suggest that blockage of TEC MCP-1 expression is a therapeutic strategy for some forms of kidney disease.

Anderson-Fabry disease (AFD) is an X-linked disorder caused by deficient activity of the lysosomal enzyme alpha-galactosidase A. The availability of enzyme replacement therapy (ERT) for this debilitating condition has led to the need for a convenient and sensitive instrument to monitor clinical effects in an individual patient. This study aimed to develop a scoring system--the Mainz Severity Score Index (MSSI)--to measure the severity of AFD and to monitor the clinical course of the disease in response to ERT. Thirty-nine patients (24 males and 15 females) with AFD were assessed using the MSSI immediately before and 1 year after commencing agalsidase alfa ERT. Control data were obtained from 23 patients in whom AFD was excluded. The MSSI of patients with AFD was significantly higher than that of patients with other severe debilitating diseases. The MSSI indicated that, although more men than women had symptoms classified as severe, overall, the median total severity scores were not significantly different between male and female patients. One year of ERT with agalsidase alfa led, in all patients, to a significant (p < 0.001) reduction in MSSI score (by a median of nine points). This study has shown that the MSSI score may be a useful, specific measure for objectively assessing the severity of AFD and for monitoring ERT-related treatment effects.