The effects of an intronic polymorphism in TOMM40 and APOE genotypes in sporadic inclusion body myositis.

A previous study showed that, in carriers of the apolipoprotein E (APOE) genotype ε3/ε3 or ε3/ε4, the presence of a very long (VL) polyT repeat allele in "translocase of outer mitochondrial membrane 40" (TOMM40) was less frequent in patients with sporadic inclusion body myositis (sIBM) compared with controls and associated with a later age of sIBM symptom onset, suggesting a protective effect of this haplotype. To further investigate the influence of these genetic factors in sIBM, we analyzed a large sIBM cohort of 158 cases as part of an International sIBM Genetics Study. No significant association was found between APOE or TOMM40 genotypes and the risk of developing sIBM. We found that the presence of at least 1 VL polyT repeat allele in TOMM40 was significantly associated with about 4 years later onset of sIBM symptoms. The age of onset was delayed by 5 years when the patients were also carriers of the APOE genotype ε3/ε3. In addition, males were likely to have a later age of onset than females. Therefore, the TOMM40 VL polyT repeat, although not influencing disease susceptibility, has a disease-modifying effect on sIBM, which can be enhanced by the APOE genotype ε3/ε3

Loss of DPP6 in neurodegenerative dementia: a genetic player in the dysfunction of neuronal excitability

Emerging evidence suggested a converging mechanism in neurodegenerative brain diseases (NBD) involving early neuronal network dysfunctions and alterations in the homeostasis of neuronal fring as culprits of neurodegeneration. In this study, we used paired-end short-read and direct long-read whole genome sequencing to investigate an unresolved autosomal dominant dementia family signifcantly linked to 7q36. We identifed and validated a chromosomal inversion of ca. 4 Mb, segregating on the disease haplotype and disrupting the coding sequence of dipeptidyl-peptidase 6 gene (DPP6). DPP6 resequencing identifed signifcantly more rare variants—nonsense, frameshift, and missense—in early-onset Alzheimer’s disease (EOAD, p value=0.03, OR=2.21 95% CI 1.05–4.82) and frontotemporal dementia (FTD, p=0.006, OR=2.59, 95% CI 1.28–5.49) patient cohorts. DPP6 is a type II transmembrane protein with a highly structured extracellular domain and is mainly expressed in brain, where it binds to the potassium channel Kv4.2 enhancing its expression, regulating its gating properties and controlling the dendritic excitability of hippocampal neurons. Using in vitro modeling, we showed that the missense variants found in patients destabilize DPP6 and reduce its membrane expression (p<0.001 and p<0.0001) leading to a loss of protein. Reduced DPP6 and/or Kv4.2 expression was also detected in brain tissue of missense variant carriers. Loss of DPP6 is known to caus

Open-label trial of anti-TNF-α in dermato- and polymyositis treated concomitantly with methotrexate

Background/Aims: To determine the efficacy of infliximab combined with weekly methotrexate in drug-naive recent-onset dermatomyositis and polymyositis. Methods: A multicentre open-label controlled trial was conducted. Disease activity was assessed using patient&apos;s and physician&apos;s disease activity assessment, manual muscle testing (MMT), handheld dynamometry, and serum CK. The primary objective was to assess the efficacy using MMT after a period of 26 weeks. Results: The study was terminated prematurely because of a low inclusion rate and a high drop-out rate due to disease progression and the occurrence of an infusion reaction. The few patients who did reach the primary endpoint showed improvement in all aspects studied. Conclusion: Infliximab combined with weekly methotrexate might be safe and well tolerated in a small subgroup of patients with drug-naive recent-onset myositis. At present, we do not advocate the use of this treatment because treatment response cannot be predicted beforehand. Copyright © 2008 S. Karger AG

Open-label trial of anti-TNF-alpha in dermato- and polymyositis treated concomitantly with methotrexate.

Item does not contain fulltextBACKGROUND/AIMS: To determine the efficacy of infliximab combined with weekly methotrexate in drug-naive recent-onset dermatomyositis and polymyositis. METHODS: A multicentre open-label controlled trial was conducted. Disease activity was assessed using patient's and physician's disease activity assessment, manual muscle testing (MMT), handheld dynamometry, and serum CK. The primary objective was to assess the efficacy using MMT after a period of 26 weeks. RESULTS: The study was terminated prematurely because of a low inclusion rate and a high drop-out rate due to disease progression and the occurrence of an infusion reaction. The few patients who did reach the primary endpoint showed improvement in all aspects studied. CONCLUSION: Infliximab combined with weekly methotrexate might be safe and well tolerated in a small subgroup of patients with drug-naive recent-onset myositis. At present, we do not advocate the use of this treatment because treatment response cannot be predicted beforehand

Disease specificity of autoantibodies to cytosolic 5 '-nucleotidase 1A in sporadic inclusion body myositis versus known autoimmune diseases

Neurological Motor Disorder

Safety and efficacy of intravenous bimagrumab in inclusion body myositis (RESILIENT): a randomised, double-blind, placebo-controlled phase 2b trial

Background Inclusion body myositis is an idiopathic inflammatory myopathy and the most common myopathy affecting people older than 50 years. To date, there are no effective drug treatments. We aimed to assess the safety, efficacy, and tolerability of bimagrumab-a fully human monoclonal antibody-in individuals with inclusion body myositis. Methods We did a multicentre, double-blind, placebo-controlled study (RESILIENT) at 38 academic clinical sites in Australia, Europe, Japan, and the USA. Individuals (aged 3685 years) were eligible for the study if they met modified 2010 Medical Research Council criteria for inclusion body myositis. We randomly assigned participants (1:1:1:1) using a blocked randomisation schedule (block size of four) to either bimagrumab (10 mg/kg, 3 mg/kg, or 1 mg/kg) or placebo matched in appearance to bimagrumab, administered as intravenous infusions every 4 weeks for at least 48 weeks. All study participants, the funder, investigators, site personnel, and people doing assessments were masked to treatment assignment. The primary outcome measure was 6-min walking distance (6MWD), which was assessed at week 52 in the primary analysis population and analysed by intention-to-treat principles. We used a multivariate normal repeated measures model to analyse data for 6MWD. Safety was assessed by recording adverse events and by electrocardiography, echocardiography, haematological testing, urinalysis, and blood chemistry. This trial is registered with ClinicalTrials.gov, number NCT01925209; this report represents the final analysis. Findings Between Sept 26, 2013, and Jan 6, 2016, 251 participants were enrolled to the study, of whom 63 were assigned to each bimagrumab group and 62 were allocated to the placebo group. At week 52, 6MWD change from baseline did not differ between any bimagrumab dose and placebo (least squares mean treatment difference for bimagrumab 10 mg/kg group, 17.6 m, SE 14.3, 99% CI -19.6 to 54.8; p=0.22; for 3 mg/kg group, 18.6 m, 14.2, -18.2 to 55.4; p=0.19; and for 1 mg/kg group, 1.3 m, 14.1, -38.0 to 35.4; p=0.93). 63 (100%) participants in each bimagrumab group and 61 (98%) of 62 in the placebo group had at least one adverse event. Falls were the most frequent adverse event (48 [76%] in the bimagrumab 10 mg/kg group, 55 [87%] in the 3 mg/kg group, 54 [86%] in the 1 mg/kg group, and 52 [84%] in the placebo group). The most frequently reported adverse events with bimagrumab were muscle spasms (32 [51%] in the bimagrumab 10 mg/kg group, 43 [68%] in the 3 mg/kg group, 25 [40%] in the 1 mg/kg group, and 13 [21%] in the placebo group) and diarrhoea (33 [52%], 28 [44%], 20 [32%], and 11 [18%], respectively). Adverse events leading to discontinuation were reported in four (6%) participants in each bimagrumab group compared with one (2%) participant in the placebo group. At least one serious adverse event was reported by 21 (33%) participants in the 10 mg/kg group, 11 (17%) in the 3 mg/kg group, 20 (32%) in the 1 mg/kg group, and 20 (32%) in the placebo group. No significant adverse cardiac effects were recorded on electrocardiography or echocardiography. Two deaths were reported during the study, one attributable to subendocardial myocardial infarction (secondary to gastrointestinal bleeding after an intentional overdose of concomitant sedatives and antidepressants) and one attributable to lung adenocarcinoma. Neither death was considered by the investigator to be related to bimagrumab. Interpretation Bimagrumab showed a good safety profile, relative to placebo, in individuals with inclusion body myositis but did not improve 6MWD. The strengths of our study are that, to the best of our knowledge, it is the largest randomised controlled trial done in people with inclusion body myositis, and it provides important natural history data over 12 months