Recombinant ADAMTS13 in Congenital Thrombotic Thrombocytopenic Purpura.

BACKGROUND: Congenital thrombotic thrombocytopenic purpura (TTP) results from severe hereditary deficiency of ADAMTS13. The efficacy and safety of recombinant ADAMTS13 and standard therapy (plasma-derived products) administered as routine prophylaxis or on-demand treatment in patients with congenital TTP is not known. METHODS: In this phase 3, open-label, crossover trial, we randomly assigned patients in a 1:1 ratio to two 6-month periods of prophylaxis with recombinant ADAMTS13 (40 IU per kilogram of body weight, administered intravenously) or standard therapy, followed by the alternate treatment; thereafter, all the patients received recombinant ADAMTS13 for an additional 6 months. The trigger for this interim analysis was trial completion by at least 30 patients. The primary outcome was acute TTP events. Manifestations of TTP, safety, and pharmacokinetics were assessed. Patients who had an acute TTP event could receive on-demand treatment. RESULTS: A total of 48 patients underwent randomization; 32 completed the trial. No acute TTP event occurred during prophylaxis with recombinant ADAMTS13, whereas 1 patient had an acute TTP event during prophylaxis with standard therapy (mean annualized event rate, 0.05). Thrombocytopenia was the most frequent TTP manifestation (annualized event rate, 0.74 with recombinant ADAMTS13 and 1.73 with standard therapy). Adverse events occurred in 71% of the patients with recombinant ADAMTS13 and in 84% with standard therapy. Adverse events that were considered by investigators to be related to the trial drug occurred in 9% of the patients with recombinant ADAMTS13 and in 48% with standard therapy. Trial-drug interruption or discontinuation due to adverse events occurred in no patients with recombinant ADAMTS13 and in 8 patients with standard therapy. No neutralizing antibodies developed during recombinant ADAMTS13 treatment. The mean maximum ADAMTS13 activity after recombinant ADAMTS13 treatment was 101%, as compared with 19% after standard therapy. CONCLUSIONS: During prophylaxis with recombinant ADAMTS13 in patients with congenital TTP, ADAMTS13 activity reached approximately 100% of normal levels, adverse events were generally mild or moderate in severity, and TTP events and manifestations were rare. (Funded by Takeda Development Center Americas and Baxalta Innovations; ClinicalTrials.gov number, NCT03393975.).

A Post-Authorization Safety Surveillance Study to Report Clinical Experience with Purified Factor IX Concentrate in Pediatric Patients with Hemophilia B.

Introduction: Purified factor IX (FIX) concentrate (IMMUNINE®, Takeda Manufacturing Austria AG, Vienna, Austria) is indicated for the treatment and prophylaxis of bleeding episodes in patients with congenital hemophilia B. Data on the use of purified FIX concentrate in patients ≤6 years old with congenital hemophilia B are limited. Aim: Document real-world clinical experience with purified FIX concentrate in routine practice for pediatric patients with hemophilia B. Methods: This prospective post-authorization safety surveillance study enrolled patients ≤6 years old with moderate or severe hemophilia B (baseline FIX ≤5%) who were prescribed purified FIX concentrate, as determined by the treating physician. The planned observation period for each patient was either 12 months or ≥50 exposure days, whichever occurred first. The primary endpoints were the occurrence of treatment-related adverse events (AEs) and serious AEs (SAEs), and inhibitor development. Results: Thirteen male patients (mean ± standard deviation age, 3.80 ± 1.76 years) enrolled and received ≥1 treatment with purified FIX concentrate. Thirty-two AEs were reported in 6 patients; 4 were SAEs. No AEs were considered related to purified FIX concentrate. No patients developed inhibitory antibodies. Inhibitor testing was not conducted in 2 patients. Eighteen bleeding episodes were treated with purified FIX concentrate in 6 patients. Hemostatic efficacy was rated as either "excellent" or "good" in all patients with an available rating. Conclusion: No treatment-related AEs were reported, and purified FIX concentrate was shown to be effective in treating and preventing bleeding episodes in pediatric patients ≤6 years old with hemophilia B.

New PLAG1-fusion transcripts in the spectrum of pediatric fibrotic, lipofibrotic, and mature lipomatous tumors.

The histomorphology of liboblastoma is highly variable and comprises different patterns that are found admixed or in pure form within a tumor. The most important features - mature lipomatous, fibrotic, lipofibrous, and myxoid - overlap with the histomorphology of several other pediatric tumor entities. Regarding the morphologic overlaps, molecular diagnostics with identification of fusion transcripts involving PLAG1 or HMGA2 is essential to identify lipoblastomas. This paper describes the diagnostic procedure in general and two new fusion transcripts of lipoblastoma, MEG3-PLAG1 and COL1A1-PLAG1. In conclusion, the algorithm to diagnose lipoblastomas among this group of pediatric fibrotic, lipofibrous and mature lipomatous tumors essentially includes histomorphology, immunohistochemistry, and molecular diagnostics.

Ultrashort echo time MRI of the lung in children and adolescents: comparison with non-enhanced computed tomography and standard post-contrast T1w MRI sequences.

OBJECTIVES: To compare the diagnostic value of ultrashort echo time (UTE) magnetic resonance imaging (MRI) for the lung versus the gold standard computed tomography (CT) and two T1-weighted MRI sequences in children. METHODS: Twenty-three patients with proven oncologic disease (14 male, 9 female; mean age 9.0 + / - 5.4 years) received 35 low-dose CT and MRI examinations of the lung. The MRI protocol (1.5-T) included the following post-contrast sequences: two-dimensional (2D) incoherent gradient echo (GRE; acquisition with breath-hold), 3D volume interpolated GRE (breath-hold), and 3D high-resolution radial UTE sequences (performed during free-breathing). Images were evaluated by considering image quality as well as distinct diagnosis of pulmonary nodules and parenchymal areal opacities with consideration of sizes and characterisations. RESULTS: The UTE technique showed significantly higher overall image quality, better sharpness, and fewer artefacts than both other sequences. On CT, 110 pulmonary nodules with a mean diameter of 4.9 + / - 2.9 mm were detected. UTE imaging resulted in a significantly higher detection rate compared to both other sequences (p < 0.01): 76.4% (84 of 110 nodules) for UTE versus 60.9% (67 of 110) for incoherent GRE and 62.7% (69 of 110) for volume interpolated GRE sequences. The detection of parenchymal areal opacities by the UTE technique was also significantly higher with a rate of 93.3% (42 of 45 opacities) versus 77.8% (35 of 45) for 2D GRE and 80.0% (36 of 45) for 3D GRE sequences (p < 0.05). CONCLUSION: The UTE technique for lung MRI is favourable in children with generally high diagnostic performance compared to standard T1-weighted sequences as well as CT. Key Points • Due to the possible acquisition during free-breathing of the patients, the UTE MRI sequence for the lung is favourable in children. • The UTE technique reaches higher overall image quality, better sharpness, and lower artefacts, but not higher contrast compared to standard post-contrast T1-weighted sequences. • In comparison to the gold standard chest CT, the detection rate of small pulmonary nodules small nodules ≤ 4 mm and subtle parenchymal areal opacities is higher with the UTE imaging than standard T1-weighted sequences.

Targeted busulfan-based reduced-intensity conditioning and HLA-matched HSCT cure hemophagocytic lymphohistiocytosis.

Reduced-intensity/reduced-toxicity conditioning and allogeneic T-cell replete hematopoietic stem cell transplantation are curative in patients with hemophagocytic lymphohistiocytosis (HLH). Unstable donor chimerism (DC) and relapses are clinical challenges . We examined the effect of a reduced-intensity conditioning regimen based on targeted busulfan to enhance myeloid DC in HLH. The European Society for Bone and Marrow Transplantation-approved reduced-intensity conditioning protocol comprised targeted submyeloablative IV busulfan, IV fludarabine, and serotherapy comprising IV alemtuzumab (0.5-0.8 mg/kg) for unrelated-donor and IV rabbit anti-T-cell globulin for related-donor transplants. We assessed toxicity, engraftment, graft-versus-host disease (GHVD), DC in blood cell subtypes, and overall survival/event-free survival. Twenty-five patients from 7 centers were treated (median age, 0.68 year). The median total dose and cumulative area under the curve of busulfan was 13.1 mg/kg (6.4-26.4) and 63.1 mg/L × h (48-77), respectively. Bone marrow, peripheral blood stem cell, or cord blood transplants from HLA-matched related (n = 7) or unrelated (n = 18) donors were administered. Donor cells engrafted in all patients (median: neutrophils d+20/platelets d+28). At last follow-up (median, 36 months; range, 8-111 months), the median DC of CD15+ neutrophils, CD3+ T cells, and CD16+56+ natural killer cells was 99.5% (10-100), 97% (30-100), and 97.5% (30-100), respectively. Eight patients (32%) developed sinusoidal obstruction syndrome, resolving after defibrotide treatment. The 3-year overall survival and event-free survival rates were both 100%. None of the patients developed acute grade III to IV GHVD. Limited chronic GVHD was encountered in 4%. This regimen achieves excellent results with stable DC in patients with HLH.

Development of Haemophilia Treatment in the Eastern Part of Germany over the Last Decade in the Kompetenznetz Hämorrhagische Diathese Ost (KHDO).

INTRODUCTION: In 2005 the Kompetenznetz Hämorrhagische Diathese Ost published epidemiologic data about patients with haemophilia A (HA) and haemophilia B (HB) in the eastern part of Germany. This study provides data about the development of treatment in these patients over the past 10 years. METHODS: Data from 12 haemophilia centres in eastern Germany were retrospectively collected for the year 2015 from patients' records. RESULTS: We evaluated 413 patients (115 children, 298 adults) with HA or HB. A total of 286 patients (69.2%) had severe haemophilia (patients with severe haemophilia, PWSH). Compared with 2005, the proportion PWSH on prophylaxis increased from 90% to 98.8% in children and from 64% to 80.2% in adults. The use of plasma-derived factor concentrates decreased from >70% to 55.3% in children and to 55.1% in adults. Mean annual factor consumption in PWSH without inhibitor was higher in 2015 compared with 2005 (children with HA: 151,489 vs. 98,894; adults with HA: 217,151 vs. 151,394; children with HB: 105,200 vs. 64,256; adults with HB: 159,185 vs. 85,295). Median annualized bleeding (annualized bleeding rate, ABR) and joint bleeding rates (annualized joint bleeding rate, AJBR) in 2015 were 2 and 0 in children and 3 and 0 in adults, respectively. In 2015 only one child (1.2%) but 101 (53.2%) adults with severe haemophilia were anti-hepatitis C virus (anti-HCV) positive. The rate of anti-HCV positive patients with active hepatitis C dropped from 63.8% to 12.9%. CONCLUSIONS: Within the last decade more patients with severe haemophilia were switched to a prophylactic regimen going along with a moderate increase in factor consumption achieving a low ABR and AJBR.

MRI as an alternative to serum ferritin for diagnosis of iron overload in children in the context of immune response after stem cell transplantation.

Multiple blood cell transfusions may cause iron overload or even liver fibrosis, requiring early diagnosis and intervention. SF is the standard for estimating iron levels in the body, but it also increases with inflammation. We hypothesized that T2 * magnetic resonance (MR) relaxometry is a more accurate alternative for follow-up in pediatric patients before and after allogenic SCT. Twenty-three children (mean age 10.2 years, 10 female, 13 male) were evaluated prospectively before SCT as well as at least 1 year after SCT with T2 * relaxometry on a 1.5 T MR-scanner to estimate liver iron concentrations from the T2 * values ("MR-Fe"). The results were compared with SF, while also considering CRP, and correlated with the number of transfusions. Overall, 24.3 transfusions were administered in average, mainly within 100 days of SCT (mean 10.5 units). Both MR-Fe and SF increased after SCT and decreased in the absence of new transfusions 1 year later without chelate therapy. This suggests regeneration of LP and iron loss, although the original states were not reached. Additionally, simultaneous peaks of CRP and SF were observed directly after SCT. MR-Fe did neither reveal these peaks nor was it associated with CRP (P = .39). We postulate that these early CRP and SF peaks after SCT are probably related to inflammatory reactions and not to iron overload. Thus, SF is not reliable for iron overload diagnosis after SCT in every condition. Beside this interaction, SF and MR-Fe revealed similar accuracy. MRI, however, has practical and economical disadvantages in routine estimation of iron.

Evaluation of liver tissue by ultrasound elastography and clinical parameters in children with multiple blood cell transfusions.

BACKGROUND: Children receiving multiple blood cell transfusions are prone to iron overload and successive tissue damage in liver parenchyma, making noninvasive screening options desirable. Ultrasound (US) elastography using acoustic radiation force impulse (ARFI) imaging enables evaluation of liver parenchyma stiffness, and MRI allows for quantification of liver iron concentration. OBJECTIVE: The objective was to correlate US elastography with MRI in children who had undergone bone marrow transplantation and to evaluate the modification of liver tissue with US in combination with clinical parameters at follow-up. MATERIALS AND METHODS: ARFI, T2*-weighted MRI and a clinical score (HepScore, based on parameters of liver function) were performed in 45 patients (24 male; mean age 9.7 years) before and 100 days and 365 days after transplantation. All received multiple blood transfusions (mean number 22.2 up until 1 year after transplantation). We correlated US findings and HepScore with MRI findings. RESULTS: We observed signs of iron accumulation in 29/45 (64.4%) patients on MRI (T2*<10 ms) and 15/45 (33.3%) showed increased tissue stiffness (ARFI>5.5 kPa). Correlation of elastography and MRI was not significant (P=0.57; n=51 matched measurements). Comparing US elastography with HepScore in receiver operating characteristic (ROC) curve analysis indicated a cut-off for affected parenchyma if HepScore was >5 points (sensitivity 67%, specificity 68%). Simultaneous increases of both indicated tissue alteration. CONCLUSION: Combining US and HepScore enabled detection of liver tissue alteration through iron overload, but we found no direct significant effect of estimated iron from MRI on ARFI imaging.

EBV miRNA expression profiles in different infection stages: A prospective cohort study.

The Epstein-Barr virus (EBV) produces different microRNAs (miRNA) with distinct regulatory functions within the infectious cycle. These viral miRNAs regulate the expression of viral and host genes and have been discussed as potential diagnostic markers or even therapeutic targets, provided that the expression profile can be unambiguously correlated to a specific stage of infection or a specific EBV-induced disorder. In this context, miRNA profiling becomes more important since the roles of these miRNAs in the pathogenesis of infections and malignancies are not fully understood. Studies of EBV miRNA expression profiles are sparse and have mainly focused on associated malignancies. This study is the first to examine the miRNA profiles of EBV reactivation and to use a correction step with seronegative patients as a reference. Between 2012 and 2017, we examined the expression profiles of 11 selected EBV miRNAs in 129 whole blood samples from primary infection, reactivation, healthy carriers and EBV seronegative patients. Three of the miRNAs could not be detected in any sample. Other miRNAs showed significantly higher expression levels and prevalence during primary infection than in other stages; miR-BHRF1-1 was the most abundant. The expression profiles from reactivation differed slightly but not significantly from those of healthy carriers, but a specific marker miRNA for each stage could not be identified within the selected EBV miRNA targets.

Prevalence of Obesity in Young Patients with Severe Haemophilia and Its Potential Impact on Factor VIII Consumption in Germany.

Similar to the general population, overweight and obesity have increasingly become a medical and economic burden also in patients with haemophilia in industrialized nations. In this study in seven German haemophilia centres, we identified a prevalence of overweight and obesity of 25.2% among 254 young patients <30 years (median: 13 years; range: 0-30 years) with severe haemophilia A and without a history of inhibitors. The median FVIII dosage based on bodyweight was significantly higher in normal weight compared with overweight or obese patients (96.9 vs. 72.9 IU/kg/week, respectively; p < 0.0001). This suggests that an individualized dosing regime which might be based on FVIII pharmacokinetics, physical activity and pre-existing haemophilic arthropathy is applied rather than dosing by bodyweight only. The bleeding rates observed in obese (median: 1; range: 0-17) versus normal weight patients (median: 2; range: 0-28) did not differ significantly (p = 0.057). Lower bleeding rates might be due to reduced activity or expected higher FVIII plasma levels in overweight patients. Due to the increasing prevalence of overweight/obesity in patients with haemophilia an interdisciplinary approach for individualized haemophilia treatment and weight loss programmes might be helpful for optimal and economical treatment for this group of patients.

Microcephaly, short stature, and limb abnormality disorder due to novel autosomal biallelic DONSON mutations in two German siblings.

Recently, variants in DONSON have been reported to cause different disorders of the microcephalic primordial dwarfism spectrum. Using whole-exome sequencing, we identified two novel, compound heterozygous DONSON variants in a pair of siblings, one of whom was previously diagnosed with Fanconi anemia. This occurred because the present cases exhibited clinical findings in addition to those of the microcephalic primordial dwarfism disorder, including severe limb malformations. These findings suggest that the DONSON and Fanconi anemia proteins could have supplementary roles in developmental processes as they have in the maintenance of genomic integrity, resulting in related disease phenotypes.

Recombinant ADAMTS-13: first-in-human pharmacokinetics and safety in congenital thrombotic thrombocytopenic purpura.

Safety, tolerability, and pharmacokinetics of recombinant ADAMTS-13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13; BAX 930; SHP655) were investigated in 15 patients diagnosed with severe congenital ADAMTS-13 deficiency (plasma ADAMTS-13 activity <6%) in a prospective phase 1, first-in-human, multicenter dose escalation study. BAX 930 was well tolerated, no serious adverse events occurred, and no anti-ADAMTS-13 antibodies were observed. After single-dose administration of BAX 930 at 5, 20, or 40 U/kg body weight to adolescents and adults, there was approximate dose proportionality with respect to maximum plasma concentration (Cmax [U/mL]) and area under the concentration-time curve (AUC [h∙U/mL]). Dose-related increases of individual ADAMTS-13:Ag and activity were observed and reached a maximum within 1 hour. With escalating BAX 930 doses administered, a dose-dependent persistence of ADAMTS-13-mediated von Willebrand factor (VWF) cleavage products and reduced VWF multimeric size were observed. This study demonstrated that pharmacokinetic parameters of BAX 930 were comparable to those estimated in previous plasma infusion studies and provided evidence of pharmacodynamic activity. This study was registered at www.clinicaltrials.gov as #NCT02216084.

Controlling the anaphylatoxin C5a in diseases requires a specifically targeted inhibition.

The terminal complement split product C5a has been described as an important mediator in inflammatory diseases. C5a is generated upon cleavage of C5 and earlier research suggests that, besides the known C5 convertases formed upon activation of the complement pathways, various enzymes could activate C5 directly. We demonstrate that eculizumab effectively blocks C5 activation when mediated by C5-convertase formation, but fails to block C5a generation resulting from direct enzymatic cleavage by trypsin and thrombin. C5a generated by these enzymes is shown to be fully biologically functional and can be blocked by IFX-1, a specific monoclonal anti-human C5a antibody. We further report clinical cases of atypical hemolytic uremic syndrome (aHUS) and C3 Glomerulonephritis (C3GN) patients under treatment with eculizumab presenting substantially elevated C5a levels. Thus, blocking the C5 convertase mediated activation of C5 may not be efficient to control C5a-mediated effects in human disease and that a targeted approach is warranted.

Health promotion for young patients with haemophilia.

The haemophilia treatment centre of the Clinic for Children and Youth Medicine in Jena extends medical care by health-promotion measures, namely: health counselling, adjuvant exercise therapy and school sports. In addition to the regular medical checks at the treatment centre patients are examined regarding physical fitness, joint situation, quality of life in general and disease-specific manner, as well as psycho-social and nutritional behaviour. Findings and medical results of the examinations are integrated into an individual advice on therapy, school sports, and health recommendations. This aimed at strengthening health-related resources and minimizing potential injuries. First long-term evaluation shows an increase of activity behaviour and physical fitness without increasing bleeding rate and maintained joint function. CONCLUSION: Combining functional prevention diagnostics and individual health counselling shows signs of improved patient's health knowledge, self-competence and physical fitness.

Health promotion for young patients with haemophilia. Counselling, adjuvant exercise therapy and school sports.

The haemophilia treatment centre of the Clinic for Children and Youth Medicine in Jena extends medical care by health-promotion measures, namely: health counselling, adjuvant exercise therapy and school sports. In addition to the regular medical checks at the treatment centre patients are examined regarding physical fitness, joint situation, quality of life in general and disease-specific manner, as well as psycho-social and nutritional behaviour. Findings and medical results of the examinations are integrated into an individual advice on therapy, school sports, and health recommendations. This aimed at strengthening health-related resources and minimizing potential injuries. First long-term evaluation shows an increase of activity behaviour and physical fitness without increasing bleeding rate and maintained joint function. CONCLUSION: Combining functional prevention diagnostics and individual health counselling shows signs of improved patient's health knowledge, self-competence and physical fitness.

Impact of high risk thrombophilia status on recurrence among children and adults with VTE: An observational multicenter cohort study.

BACKGROUND: Antithrombin [AT]-, protein C [PC]- or protein S [PS]-deficiency [D] constitutes a major risk factor for venous thromboembolism [VTE]. Primary study objective was to evaluate if the clinical presentation at first VTE onset differs between children and adults and to compare the individual recurrence risk among patients with respect to age at onset and their thrombophilia status ATD, PCD or PSD. METHODS/PATIENTS/RESULTS: In 137 of 688 consecutively enrolled pediatric and adult VTE patients we calculated the absolute risk of VTE recurrence and event-free-survival adjusted for thrombophilia and positive family VTE history. At first VTE children manifested i) with a lower rate of pulmonary embolism, ii) a higher rate of cerebral vascular events or multiple VTEs, and iii) showed a higher proportion of unprovoked VTE compared to adolescents and adults. Adult patients reported more often a positive VTE history compared to younger study participants. The adjusted odds of recurrence in adults was 2.05 compared to children. CONCLUSION: At disease manifestation children and adults differ with respect to i) thrombotic locations, ii) percentage of unprovoked versus provoked VTE, and iii) different rates of positive VTE family histories. Furthermore, adults showed a two-fold increase risk of VTE recurrence compared to children.

Malignancy-associated haemophagocytic lymphohistiocytosis in children and adolescents.

Haemophagocytic lymphohistiocytosis (HLH) in the context of malignancy is mainly considered a challenge of adult haematology. While this association is also observed in children, little is known regarding inciting factors, appropriate treatment and prognosis. We retrospectively analysed 29 paediatric and adolescent patients for presenting features, type of neoplasm or preceding chemotherapy, treatment and outcome. Haemophagocytic lymphohistiocytosis was considered triggered by the malignancy (M-HLH) in 21 patients, most of whom had T- (n = 12) or B-cell neoplasms (n = 7), with Epstein-Barr virus as a co-trigger in five patients. In eight patients, HLH occurred during chemotherapy (Ch-HLH) for malignancy, mainly acute leukaemias (n = 7); an infectious trigger was found in seven. In M- and Ch-HLH, median overall survival was 1·2 and 0·9 years, and the 6 month survival rates were 67% and 63%, respectively. Seven of 11 deceased M-HLH patients exhibited active malignancy and HLH at the time of death, while only two out of five deceased Ch-HLH patients had evidence of active HLH. To overcome HLH, malignancy- and HLH-directed treatments were administered in the M-HLH cohort; however, it was not possible to determine superiority of one approach over the other. For Ch-HLH, treatment ranged from postponement of chemotherapy to the use of etoposide-containing regimens.