Brigitte Bader-Meunier

Safety and efficacy of rituximab in systemic lupus erythematosus: Results from 136 patients from the French autoimmunity and rituximab registry

OBJECTIVE A number of open-label studies have suggested the potential benefit of rituximab (RTX) in systemic lupus erythematosus (SLE). However, in 2 recent randomized controlled trials (RCTs) of RTX, the primary end points were not met. We undertook this study to evaluate the safety and efficacy of RTX in off-trial patients with SLE seen in regular clinical practice. METHODS We analyzed prospective data from the French AutoImmunity and Rituximab (AIR) registry, which includes data on patients with autoimmune disorders treated with RTX. RESULTS One hundred thirty-six patients received treatment for SLE. The mean +/- SD score on the Safety of Estrogens in Lupus Erythematosus: National Assessment (SELENA) version of the SLE Disease Activity Index (SLEDAI) was 11.3 +/- 8.9 at baseline. Severe infections were noted in 12 patients (9%), corresponding to a rate of 6.6/100 patient-years. Most severe infections occurred within the first 3 months after the last RTX infusion. Five patients died, due to severe infection (n = 3) or refractory autoimmune disease (n = 2). Overall response was observed in 80 of 113 patients (71%) by the SELENA-SLEDAI assessment. Efficacy did not differ significantly between patients receiving RTX monotherapy and those receiving concomitant immunosuppressive agents (who had higher baseline disease activity). Articular, cutaneous, renal, and hematologic improvements were noted in 72%, 70%, 74%, and 88% of patients, respectively. Among responders, 41% experienced a relapse of disease, with a response in 91% after retreatment with RTX. CONCLUSION Data from the AIR registry show a satisfactory tolerance profile and clinical efficacy of RTX in patients with SLE. The contrasting results with those from recent RCTs leave open the question of the therapeutic use of RTX in SLE. Additional controlled studies with new designs are needed to define the place of RTX in the therapeutic arsenal for SLE.

Gain-of-function mutations in IFIH1 cause a spectrum of human disease phenotypes associated with upregulated type I interferon signaling

The type I interferon system is integral to human antiviral immunity. However, inappropriate stimulation or defective negative regulation of this system can lead to inflammatory disease. We sought to determine the molecular basis of genetically uncharacterized cases of the type I interferonopathy Aicardi-Goutières syndrome and of other undefined neurological and immunological phenotypes also demonstrating an upregulated type I interferon response. We found that heterozygous mutations in the cytosolic double-stranded RNA receptor gene IFIH1 (also called MDA5) cause a spectrum of neuroimmunological features consistently associated with an enhanced interferon state. Cellular and biochemical assays indicate that these mutations confer gain of function such that mutant IFIH1 binds RNA more avidly, leading to increased baseline and ligand-induced interferon signaling. Our results demonstrate that aberrant sensing of nucleic acids can cause immune upregulation.

Tartrate-resistant acid phosphatase deficiency causes a bone dysplasia with autoimmunity and a type I interferon expression signature

We studied ten individuals from eight families showing features consistent with the immuno-osseous dysplasia spondyloenchondrodysplasia. Of particular note was the diverse spectrum of autoimmune phenotypes observed in these individuals (cases), including systemic lupus erythematosus, Sjögrens syndrome, hemolytic anemia, thrombocytopenia, hypothyroidism, inflammatory myositis, Raynauds disease and vitiligo. Haplotype data indicated the disease gene to be on chromosome 19p13, and linkage analysis yielded a combined multipoint log10 odds (LOD) score of 3.6. Sequencing of ACP5, encoding tartrate-resistant acid phosphatase, identified biallelic mutations in each of the cases studied, and in vivo testing confirmed a loss of expressed protein. All eight cases assayed showed elevated serum interferon alpha activity, and gene expression profiling in whole blood defined a type I interferon signature. Our findings reveal a previously unrecognized link between tartrate-resistant acid phosphatase activity and interferon metabolism and highlight the importance of type I interferon in the genesis of autoimmunity.

Occurrence of myeloproliferative disorder in patients with Noonan syndrome

We report four cases of Noonan syndrome associated with chronic myelomonocytic leukemia in childhood. These children shared some hematologic features: thrombocytopenia, splenomegaly in the first months of life, occurrence of chronic myelomonocytic leukemia without abnormalities of the initial bone marrow karyotype, and, in three cases, improvement of the hematologic disease. A common pathophysiologic process in such patients is suggested.

A phase II, multicenter, open-label study evaluating dosing and preliminary safety and efficacy of canakinumab in systemic juvenile idiopathic arthritis with active systemic features.

OBJECTIVE To assess dosing, preliminary safety, and efficacy of canakinumab, a fully human anti-interleukin-1β (anti-IL-1β) antibody, in children with systemic juvenile idiopathic arthritis (JIA) and active systemic features. METHODS In this phase II, multicenter, open-label, dosage-escalation study, children with systemic JIA who were ≥4 years of age, had fever, and were receiving ≤0.4 mg/kg/day of corticosteroids were administered a single subcutaneous dose of canakinumab, 0.5-9 mg/kg of body weight, and were redosed upon relapse. Response to treatment was assessed according to an adaptation of the American College of Rheumatology (ACR) pediatric criteria for improvement. RESULTS A total of 23 children ages 4-19 years with active disease were enrolled. Of these, 1 patient was excluded from analysis, and 3 of the reenrolled patients were included twice in the efficacy analysis. By day 15 of the first treatment cycle, 15 of 25 patients (60%) had achieved an adapted ACR Pediatric 50 response, with 4 of them achieving inactive disease status. Response was sustained over time, with 11 of 13 patients able to maintain their response throughout the study. In 8 of the 11 responders who had been receiving steroids at baseline, the steroid dosage was decreased from a mean of 0.38 mg/kg/day to 0.13 mg/kg/day over the first 5 months, and 4 of them were able to discontinue steroids. At a dose of 4 mg/kg of canakinumab given subcutaneously every 4 weeks, the median percentage of patients predicted to relapse within 4 weeks was estimated to be 6% (95% confidence interval 1-21). Therapy was generally well tolerated and few patients experienced injection-site reactions. CONCLUSION Canakinumab has a promising preliminary safety and efficacy profile in this limited cohort. Based on the findings of this trial, further studies in a larger population of children with systemic JIA are warranted.

Macrophage activation syndrome in juvenile systemic lupus erythematosus: A multinational multicenter study of thirty‐eight patients

OBJECTIVE To describe the clinical and laboratory features of macrophage activation syndrome as a complication of juvenile systemic lupus erythematosus (SLE). METHODS Cases of juvenile SLE-associated macrophage activation syndrome were provided by investigators belonging to 3 pediatric rheumatology networks or were found in the literature. Patients who had evidence of macrophage hemophagocytosis on bone marrow aspiration were considered to have definite macrophage activation syndrome, and those who did not have such evidence were considered to have probable macrophage activation syndrome. Clinical and laboratory findings in patients with macrophage activation syndrome were contrasted with those of 2 control groups composed of patients with active juvenile SLE without macrophage activation syndrome. The ability of each feature to discriminate macrophage activation syndrome from active disease was evaluated by calculating sensitivity, specificity, and area under the receiver operating characteristic curve. RESULTS The study included 38 patients (20 with definite macrophage activation syndrome and 18 with probable macrophage activation syndrome). Patients with definite and probable macrophage activation syndrome were comparable with regard to all clinical and laboratory features of the syndrome, except for a greater frequency of lymphadenopathy, leukopenia, and thrombocytopenia in patients with definite macrophage activation syndrome. Overall, clinical features had better specificity than sensitivity, except for fever, which was highly sensitive but had low specificity. Among laboratory features, the best sensitivity and specificity was achieved using hyperferritinemia, followed by increased levels of lactate dehydrogenase, hypertriglyceridemia, and hypofibrinogenemia. Based on the results of statistical analysis, preliminary diagnostic guidelines for macrophage activation syndrome in juvenile SLE were developed. CONCLUSION Our findings indicate that the occurrence of unexplained fever and cytopenia, when associated with hyperferritinemia, in a patient with juvenile SLE should raise the suspicion of macrophage activation syndrome. We propose preliminary guidelines for this syndrome in juvenile SLE to facilitate timely diagnosis and correct classification of patients.

Two-year results from an open-label, multicentre, phase III study evaluating the safety and efficacy of canakinumab in patients with cryopyrin-associated periodic syndrome across different severity phenotypes

Objective Longer-term effects of prolonged selective interleukin-1β blockade with canakinumab were evaluated in the largest cohort of cryopyrin-associated periodic syndrome (CAPS) patients studied to date. Methods Adult and paediatric CAPS patients (n=166, including canakinumab-naive and pretreated patients from previous studies) received canakinumab subcutaneously 150 mg or 2 mg/kg (≤40 kg) every 8 weeks for up to 2 years. Response and relapse was assessed using scores for disease activity, skin rash and C-reactive protein (CRP) and/or serum amyloid A (SAA) levels. Results Complete response was achieved in 85 of 109 canakinumab-naive patients (78%; 79/85 patients within 8 days, and five patients between days 10 and 21). Of 141 patients with an available relapse assessment, 90% did not relapse, their CRP/SAA levels normalised (<10 mg/l) by day 8, and remained in the normal range thereafter. Median treatment duration was 414 days (29–687 days). Upward adjustments of dose or frequency were needed in 24.1% patients; mostly children and those with severe CAPS. Predominant adverse events (AE) were infections (65.7%) of mostly mild-to-moderate severity. Serious AE reported in 18 patients (10.8%) were mainly infections and were responsive to standard treatment. The majority of patients (92%) reported having no injection-site reactions and only 8% patients reported mild-to-moderate reactions. Patients receiving vaccination (15%) showed normal immune response. Conclusions Subcutaneous canakinumab 150 mg every 8 weeks was well tolerated and provided substantial disease control in children and adults across all CAPS phenotypes. Higher canakinumab doses in younger patients and more severe CAPS disease were efficacious in achieving complete responses without evidence of increased AE. Trial registration number: NCT00685373 (clinicaltrials.gov)

Mevalonate Kinase Deficiency: A Survey of 50 Patients

OBJECTIVE: The goal of this study was to describe the spectrum of clinical signs of mevalonate kinase deficiency (MKD). METHODS: This was a retrospective French and Belgian study of patients identified on the basis of MKD gene mutations. RESULTS: Fifty patients from 38 different families were identified, including 1 asymptomatic patient. Symptoms began during the first 6 months of life in 30 patients (60%) and before the age of 5 years in 46 patients (92%). Symptoms consisted of febrile diarrhea and/or rash in 23 of 35 patients (66%). Febrile attacks were mostly associated with lymphadenopathy (71%), diarrhea (69%), joint pain (67%), skin lesions (67%), abdominal pain (63%), and splenomegaly (63%). In addition to febrile attacks, 27 patients presented with inflammatory bowel disease, erosive polyarthritis, Sjögren syndrome, and other chronic neurologic, renal, pulmonary, endocrine, cutaneous, hematologic, or ocular symptoms. Recurrent and/or severe infections were observed in 13 patients, hypogammaglobulinemia in 3 patients, and renal angiomyolipoma in 3 patients. Twenty-nine genomic mutations were identified; the p.Val377Ile mutation was the most frequently found (29 of 38 families). Three patients died of causes related to MKD. The disease remained highly active in 17 of the 31 surviving symptomatic patients followed up for >5 years, whereas disease activity decreased over time in the other 14 patients. Interleukin 1 antagonists were the most effective biological agents tested, leading to complete or partial remission in 9 of 11 patients. CONCLUSION: MKD is not only an autoinflammatory syndrome but also a multisystemic inflammatory disorder, a possible immunodeficiency disorder, and a condition that predisposes patients to the development of renal angiomyolipoma.

Anti-HMGCR Autoantibodies in European Patients With Autoimmune Necrotizing Myopathies: Inconstant Exposure to Statin

AbstractNecrotizing autoimmune myopathy (NAM) is a group of acquired myopathies characterized by prominent myofiber necrosis with little or no muscle inflammation. Recently, researchers identified autoantibodies (aAb) against 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) in patients with NAM, especially in statin-exposed patients. Here we report what is to our knowledge the first European cohort of patients with NAM.The serum of 206 patients with suspicion of NAM was tested for detection of anti-HMGCR aAb using an addressable laser bead immunoassay. Forty-five patients were found to be anti-HMGCR positive. Their mean age was 48.9 ± 21.9 years and the group was predominantly female (73.3%). Statin exposure was recorded in 44.4% of patients. Almost all patients had a muscular deficit (97.7%), frequently severe (Medical Research Council [MRC] 5 ⩽3 in 75.5%). Subacute onset (<6 mo) was noted for most of them (64.4%). Nevertheless, 3 patients (6.6%) had a slowly progressive course over more than 10 years. Except for weight loss (20%), no extramuscular sign was observed. The mean CK level was high (6941 ± 8802 IU/L) and correlated with muscle strength evaluated by manual muscle testing (r = −0.37, p = 0.03). Similarly, anti-HMGCR aAb titers were correlated with muscular strength (r = −0.31; p = 0.03) and CK level (r = 0.45; p = 0.01). Mean duration of treatment was 34.1 ± 40.8 months, and by the end of the study no patient had been able to stop treatment.This study confirms the observation and description of anti-HMGCR aAb associated with NAM. The majority of patients were statin naive and needed prolonged treatments. Some patients had a dystrophic-like presentation. Anti-HMGR aAb titers correlated with CK levels and muscle strength, suggesting their pathogenic role.

FAS-L, IL-10, and double-negative CD4- CD8- TCR alpha/beta+ T cells are reliable markers of autoimmune lymphoproliferative syndrome (ALPS) associated with FAS loss of function.

Autoimmune lymphoproliferative syndrome (ALPS) is characterized by splenomegaly, lymphadenopathy, hypergammaglobulinemia, accumulation of double-negative TCRalphabeta(+) CD4(-)CD8(-) T cells (DNT cells), and autoimmunity. Previously, DNT cell detection and a functional defect of T cells in a FAS-induced apoptosis test in vitro had been used for ALPS diagnosis. However, a functional defect can also be detected in mutation-positive relatives (MPRs) who remain free of any ALPS-related disease. In contrast, lymphocytes from patients carrying a somatic mutation of FAS exhibit normal sensitivity to FAS-induced apoptosis in vitro. We assessed the soluble FAS-L concentration in the plasma of ALPS patients carrying FAS mutations. Overall, we showed that determination of the FAS-L represents, together with the IL-10 concentration and the DNT cell percentage, a reliable tool for the diagnosis of ALPS.