Pharmacokinetics, pharmacodynamics, and safety of fesomersen, a novel antisense inhibitor of factor XI, in healthy Chinese, Japanese, and Caucasian volunteers.

The inhibition of coagulation factor XI (FXI) presents an attractive approach for anticoagulation as it is not expected to increase the risk of clinically relevant bleeding and is anticipated to be at least as effective as currently available anticoagulants. Fesomersen is a conjugated antisense oligonucleotide that selectively inhibits the expression of FXI. The article describes three clinical studies that investigated the safety, pharmacokinetic (PK), and pharmacodynamic (PD) profiles of fesomersen after subcutaneous (s.c.) injection to healthy participants. The studies included participants from diverse ethnic backgrounds (Caucasian, Japanese, and Chinese). Fesomersen demonstrated good safety and tolerability in all three studies. No major bleeding events were observed. After single-dose s.c. injection, fesomersen was rapidly absorbed into the systemic circulation, with maximum fesomersen-equivalent (fesomersen-eq) concentrations (Cmax) in plasma observed within a few hours. After reaching Cmax, plasma fesomersen-eq concentrations declined in a biphasic fashion. The PD analyses showed that the injection of fesomersen led to dose-dependent reductions in FXI activity and increases in activated partial thromboplastin time (aPTT). The maximum observed PD effects were reached between Day 15 and 30, and FXI activity and aPTT returned to near-baseline levels by Day 90 after a single dose. The PK/PD profiles after a single injection were similar among the various ethnic groups. Collectively, the study results suggest that fesomersen has a favorable safety profile and predictable and similar PK and PD profiles across Chinese, Japanese, and Caucasian participants.

A genome-wide association study identifies 6p21 as novel risk locus for dilated cardiomyopathy.

AIMS: Dilated cardiomyopathy (DCM) is one of the leading causes for cardiac transplantations and accounts for up to one-third of all heart failure cases. Since extrinsic and monogenic causes explain only a fraction of all cases, common genetic variants are suspected to contribute to the pathogenesis of DCM, its age of onset, and clinical progression. By a large-scale case-control genome-wide association study we aimed here to identify novel genetic risk loci for DCM. METHODS AND RESULTS: Applying a three-staged study design, we analysed more than 4100 DCM cases and 7600 controls. We identified and successfully replicated multiple single nucleotide polymorphism on chromosome 6p21. In the combined analysis, the most significant association signal was obtained for rs9262636 (P = 4.90 × 10(-9)) located in HCG22, which could again be replicated in an independent cohort. Taking advantage of expression quantitative trait loci (eQTL) as molecular phenotypes, we identified rs9262636 as an eQTL for several closely located genes encoding class I and class II major histocompatibility complex heavy chain receptors. CONCLUSION: The present study reveals a novel genetic susceptibility locus that clearly underlines the role of genetically driven, inflammatory processes in the pathogenesis of idiopathic DCM.

The functional -374T/A polymorphism of the receptor for advanced glycation end products may modulate Crohn's disease.

The receptor for advanced glycation end products (RAGE) is involved in innate immune mechanisms. Polymorphisms of the RAGE gene have been described as a factor amplifying inflammation in susceptible patients, but the association with Crohn's disease (CD) is not known. The coding RAGE polymorphism G82S (rs2070600) and two promoter polymorphisms, -374T/A (rs1800624) and -429T/C (rs1800625), were studied in two samples from Germany and the United States consisting of 421 and 317 CD patients and 549 and 218 controls, respectively. To test the functional relevance, additional data on serum soluble RAGE (sRAGE), tissue RNA, and protein levels were collected and immunohistochemical stainings of bowel tissue of CD patients and healthy controls as well as models of experimental (dextran sodium sulfate-induced) colitis in RAGE knockout and wild-type mice were performed. The -374T/A RAGE promotor single nucleotide polymorphism (SNP) was negatively associated with CD (odds ratio = 0.708, 95% confidence interval = 0.535-0.938, P = 0.016) and with stenosis (OR = 0.627, P = 0.04) in the German sample. Transmission disequilibrium testing confirmed an undertransmission of the -374A allele. Serum sRAGE levels were higher in patients in complete remission of the -374AA/TA group (1,975 ± 299 pg/ml; -374TT group: 1,310 ± 153 pg/ml SE, P < 0.05) and showed a trend toward decreased levels in CD patients with active disease compared with CD patients in remission. Further in vitro and in vivo studies indicated that an increase of sRAGE ameliorates inflammation. The -429T/C and the G82S polymorphism were not associated with CD. The -374T/A RAGE polymorphism leading to facilitated RAGE gene transcription may to some degree protect from developing a stricturing subphenotype of CD, most likely by increasing levels of sRAGE, which neutralizes proinflammatory mediators.

HBEGF, SRA1, and IK: Three cosegregating genes as determinants of cardiomyopathy.

Human dilated cardiomyopathy (DCM), a disorder of the cardiac muscle, causes considerable morbidity and mortality and is one of the major causes of sudden cardiac death. Genetic factors play a role in the etiology and pathogenesis of DCM. Disease-associated genetic variations identified to date have been identified in single families or single sporadic patients and explain a minority of the etiology of DCM. We show that a 600-kb region of linkage disequilibrium (LD) on 5q31.2-3, harboring multiple genes, is associated with cardiomyopathy in three independent Caucasian populations (combined P-value = 0.00087). Functional assessment in zebrafish demonstrates that at least three genes, orthologous to loci in this LD block, HBEGF, IK, and SRA1, result independently in a phenotype of myocardial contractile dysfunction when their expression is reduced with morpholino antisense reagents. Evolutionary analysis across multiple vertebrate genomes suggests that this heart failure-associated LD block emerged by a series of genomic rearrangements across amphibian, avian, and mammalian genomes and is maintained as a cluster in mammals. Taken together, these observations challenge the simple notion that disease phenotypes can be traced to altered function of a single locus within a haplotype and suggest that a more detailed assessment of causality can be necessary.

Impact of inherited thrombophilia on venous thromboembolism in children: a systematic review and meta-analysis of observational studies.

BACKGROUND: The aim of the present study was to estimate the impact of inherited thrombophilia (IT) on the risk of venous thromboembolism (VTE) onset and recurrence in children by a meta-analysis of published observational studies. METHODS AND RESULTS: A systematic search of electronic databases (Medline, EMBASE, OVID, Web of Science, The Cochrane Library) for studies published from 1970 to 2007 was conducted using key words in combination as both MeSH terms and text words. Citations were independently screened by 2 authors, and those meeting the inclusion criteria defined a priori were retained. Data on year of publication, study design, country of origin, number of patients/controls, ethnicity, VTE type, and frequency of recurrence were abstracted. Heterogeneity across studies was evaluated, and summary odds ratios and 95% CIs were calculated with both fixed-effects and random-effects models. Thirty-five of 50 studies met inclusion criteria. No significant heterogeneity was discerned across studies. Although >70% of patients had at least 1 clinical risk factor for VTE, a statistically significant association with VTE onset was demonstrated for each IT trait evaluated (and for combined IT traits), with summary odds ratios ranging from 2.63 (95% CI, 1.61 to 4.29) for the factor II variant to 9.44 (95% CI, 3.34 to 26.66) for antithrombin deficiency. Furthermore, a significant association with recurrent VTE was found for all IT traits except the factor V variant and elevated lipoprotein(a). CONCLUSIONS: The present meta-analysis indicates that detection of IT is clinically meaningful in children with, or at risk for, VTE and underscores the importance of pediatric thrombophilia screening programs.

The Crohn's disease susceptibility gene DLG5 as a member of the CARD interaction network.

Discs large homolog 5 (DLG5), a member of the membrane-associated guanylate kinase (MAGUK) family of scaffolding proteins, has been associated with Crohn's disease (CD), but its role in the pathogenesis of this inflammatory bowel disease is disputed. Here, we used sequence comparisons and phylogenies to analyse the DLG5 gene and its protein product. We identified a 5' exon, which codes for an N-terminal caspase recruitment domain (CARD) and experimentally confirmed its expression in colonic tissue. DLG5 shares this new domain with nucleotide-binding oligomerisation domain containing 2 (NOD2); the first CD susceptibility factor identified in genetic studies. An extensive phylogenetic analysis redefines the family organisation of the MAGUK proteins: DLG5 is closely related to CARD10, CARD11 and CARD14, CARD-containing proteins which initiate pro-inflammatory NFkappaB signalling, but not to DLG1-4, previously considered the closest related proteins. Therefore, we suggest renaming DLG5 to correctly annotate the gene in its phylogenetic and functional context. Our study provides evidence that the scaffolding protein DLG5 belongs to the CARD protein family. Thus, DLG5 likely acts in the regulation of NFkB activation or caspase activation as part of host defence mechanisms. As there is substantial crosstalk between CARD-mediated pathways, both CD susceptibility genes, NOD2 and DLG5, may interact functionally to contribute to CD risk.

Effects of primary and secondary prophylaxis on the clinical expression of joint damage in children with severe haemophilia A. Results of a multicenter non-concurrent cohort study.

Patients with severe haemophilia A (HA) can either be treated by regular FVIII infusions twice or three times per week (prophylaxis), or only in case of bleeding episodes (on-demand). Whereas prophylaxis reduces the number of bleeding episodes and may therefore prevent the development of haemophilic arthropathy, there is still a lot of controversy surrounding recommendations on age and dose at start of prophylactic regimens. The present database study was performed to investigate the role of primary versus secondary prophylaxis in HA children. The outcome variable was imaging-proven haemophilic joint damage. Forty-two children were initially treated with primary prophylaxis following the first bleeding episode, and were frequency-matched (year of birth, catchment area) to 67 patients receiving "on-demand" therapy with an early switch to "secondary prophylaxis". In multivariate analysis adjusted for the HA mutation type and the presence or absence of thrombophilia, the Pettersson score investigated at a median age of 12.5 years in joints with at least one documented bleeding episode was not significantly different between the two patient groups (p = 0.944), and no statistically significant differences were found in patients with target joints (p = 0.3), nor in children in whom synovitis had occurred (p = 0.77). No conclusion can be drawn from the data presented herein whether primary prophylaxis or an early start of secondary prophylaxis is superior with respect to joint outcome in children with severe HA.

CRP gene haplotypes, serum CRP, and cerebral small-vessel disease: the Rotterdam Scan Study and the MEMO Study.

BACKGROUND AND PURPOSE: It remains unclear whether C-reactive protein (CRP) is a serum marker for atherothrombotic disease or a causal factor in the pathogenesis of atherosclerosis. We explored the association between CRP gene variations and cerebral small-vessel disease (SVD) in the Rotterdam Scan Study (N=1035) and the MEMO Study (N=268). METHODS: Common haplotypes within the CRP gene were determined by genotype-tagging single-nucleotide polymorphisms. Then their relation with periventricular and subcortical white matter lesions and the prevalence of lacunar brain infarcts was explored by regression analyses. RESULTS: There was no association between CRP haplotypes and measures of cerebral SVD in either study. There was no effect modification of the association between serum CRP levels and measures of SVD by CRP haplotypes. CONCLUSIONS: Our observations suggest that CRP is not causally involved in the pathogenesis of SVD.

DLG5 R30Q variant is a female-specific protective factor in pediatric onset Crohn's disease.

OBJECTIVE: A significant association between the DLG5 variant (R30Q) and inflammatory bowel disease (IBD) has been confirmed in several independent adult IBD cohorts. There is growing evidence that gender significantly influences R30Q susceptibility in Crohn's disease (CD). Pediatric onset CD features a significantly lower incidence for female children compared with male children. We, therefore, studied the influence of gender on R30Q susceptibility in an exclusively pediatric onset IBD cohort. DESIGN: A total of 281 CD (181 trios) and 479 population-based controls were genotyped for DLG5 R30Q using Taqman assay. Association was tested by case-control and transmission disequilibrium testing analysis. Multivariate logistic regression was performed to investigate gene-gene and gene-gender interactions, as well as genotype-phenotype correlations. RESULTS: Overall allele frequency for R30Q was 8.5% in CD and 10.3% in controls. Logistic regression showed R30Q had no association with CD (OR 0.81, 95% CI 0.55-1.20, P= 0.3) when the cohort was analyzed as a whole. Stratified by gender, a significant negative association was detected for R30Q in female children (OR 0.39, 95% CI 0.2-0.77, P= 0.006), but not in male children. Gender was found to be an effect modifier of the association between R30Q and CD as the odds ratios in female children and male children differed significantly. The gender-specific association of R30Q and CD was independent of additional CD risk factors such as CARD15 and IBD5. CONCLUSIONS: DLG5 has a gender-specific role in the susceptibility of pediatric CD. Specifically, the significant negative association found between DLG5 R30Q and CD in female children suggests DLG5 may have a protective effect in CD susceptibility for female children.

Role of discs large homolog 5.

In 2004, an association of genetic variation in the discs large homolog 5 (DLG5) gene with inflammatory bowel disease (IBD) was described in two large European study samples. The initial report of DLG5 as a novel IBD susceptibility gene sparked a multitude of studies investigating its effect on CD and IBD, respectively, leading to controversial findings and ongoing discussions concerning the validity of the initial association finding and its role in the aetiology of Crohn disease. This review aims to summarize the current state of knowledge and to place the reported findings in the context of current concepts of complex diseases. This includes aspects of statistical power, phenotype differences and genetic heterogeneity between different populations as well as gene-gene and gene-environment interactions.

Evidence of transmission ratio distortion of DLG5 R30Q variant in general and implication of an association with Crohn disease in men.

Recently, we described the association of genetic variation in the discs large homolog 5 (DLG5) gene with inflammatory bowel disease (IBD) in a large European study sample (Stoll et al. in Nat Genet 36:476-480, 2004). Here, we report that the R30Q variant constitutes a susceptibility factor for Crohn disease (CD) in men [odds ratio (OR)=2.49, 95% confidence interval (CI) 1.53-4.06, P<0.001] but not women (OR=1.01, 95% CI=0.70-1.45, P=0.979) using multivariate logistic regression analyses in a unified study sample from Germany, Italy and Quebec. R30Q is a significant predictor for CD in men even when accounting for CARD15 and IBD5 risk variants (adjusted OR=2.41, 95% CI=1.41-4.12, P=0.001). The observed association is driven by a gender-dependent transmission ratio distortion (TRD) among healthy controls (frequency of Q allele: men 5.2%, women 11.3%), an effect that is offset in CD patients (frequency of Q allele: men 10.1%, women 10.9%). This finding is further substantiated by two non-IBD study samples, one of which consists of a newborn screening sample (newborn males 7.1%; newborn females 11%, P=0.036). Further investigation of the observed TRD may contribute towards enlightening the role of DLG5 in physiological processes influencing transmission of chromosomes to the surviving offspring, which, in turn, may help in understanding its implication in the development of CD among men.