Efficacy and safety of avatrombopag in combination with immunosuppressive therapy in treatment-naïve and relapsed/refractory severe aplastic anaemia: protocol for the DIAAMOND-Ava-FIRST and DIAAMOND-Ava-NEXT Bayesian Optimal Phase II trials.

INTRODUCTION: Immunosuppressive therapy (IST) with antithymocyte globulin (ATG) and ciclosporin is standard of care for patients with severe aplastic anaemia (sAA) not eligible or suitable for allogeneic stem cell transplant. While patients respond to IST, few achieve complete responses and a significant proportion are refractory or relapse. The addition of eltrombopag, a thrombopoietin-receptor agonist (TPO-A), to IST has been shown to improve haematological responses in sAA. Avatrombopag is a second-generation TPO-A with potential advantages over eltrombopag. However, to date avatrombopag has not been studied in sAA. METHODS AND ANALYSIS: Investigator-initiated, single-arm registry-based Bayesian Optimal Phase II trial of avatrombopag conducted in two cohorts, patients with untreated sAA (FIRST cohort) and in patients with sAA that has relapsed or is refractory to IST (NEXT cohort). In the FIRST cohort, participants receive IST (equine ATG and ciclosporin) plus avatrombopag from day 1 until day 180 at 60 mg oral daily, with dose adjusted according to platelet count. Participants in the NEXT cohort receive avatrombopag at 60 mg oral daily from day 1 until day 180, with or without additional IST at the discretion of the treating clinician.For each cohort, two primary endpoints (haematological response and acquired clonal evolution) are jointly monitored and the trial reviewed at each interim analysis where a 'go/no-go' decision is made by evaluating the posterior probability of the events of interests. ETHICS AND DISSEMINATION: The trial has received ethics approval (Monash Health RES-18-0000707A). The trial conduct will comply with ICH-GCP and all applicable regulatory requirements. The results of the trial will be submitted to a peer-review journal for publication. TRIAL REGISTRATION NUMBER: ACTRN12619001042134, ACTRN12619001043123.

The Australian Aplastic Anaemia and other Bone Marrow Failure Syndromes Registry.

The bone marrow failure syndromes (BMFS) are a diverse group of acquired and inherited diseases which may manifest in cytopenias, haematological malignancy and/or syndromic multisystem disease. Patients with BMFS frequently experience poor outcomes, and improved treatment strategies are needed. Collation of clinical characteristics and patient outcomes in a national disease-specific registry represents a powerful tool to identify areas of need and support clinical and research collaboration. Novel treatment strategies such as gene therapy, particularly in rare diseases, will depend on the ability to identify eligible patients alongside the molecular genetic features of their disease that may be amenable to novel therapy. The Australian Aplastic Anaemia and other Bone Marrow Failure Syndromes Registry (AAR) aims to improve outcomes for all paediatric and adult patients with BMFS in Australia by describing the demographics, treatments (including supportive care) and outcomes, and serving as a resource for research and practice improvement.

Direct oral anticoagulants and cardiac surgery: A descriptive study of preoperative management and postoperative outcomes.

OBJECTIVE: Recommendations for perioperative management of direct oral anticoagulant (DOAC) treatment in cardiac surgery are lacking. To establish a standardized approach for these patients, we compared hemorrhagic complications and clinical outcomes in patients on DOAC medication, patients on vitamin K antagonists (VKA), and patients without preoperative anticoagulation. METHODS: All 3 groups underwent major cardiac surgery and were retrospectively analyzed: patients on DOAC were advised to take their last DOAC dose 4 days before hospital admission, and DOAC plasma levels were measured the day before surgery. In patients with plasma levels of >30 ng/mL, surgery was postponed until plasma level was below this threshold level. Postoperative chest tube drainage, bleeding complications, use of blood products, and thromboembolic events were collected for all groups. RESULTS: A total of 5439 patients no anticoagulation, 239 patients on VKA, and 487 patients on DOAC medication were included between April 2014 and July 2017. Adjusted postoperative chest tube drainage did not differ between the DOAC and VKA groups for the strategy applied in this study (380 mL/12 hours vs 360 mL/12 hours). Moreover, secondary endpoint measures, such as rethoracotomy (30 [6.16%] vs 15 [6.28%]), 30-day-mortality 12 [2.46%] vs 7 [2.93%]), blood-product use, and stroke, were not significantly different through implementation of our standardized study management (P > .05). CONCLUSIONS: Our standardized management for perioperative discontinuation of DOAC therapy may provide a safe approach to minimize hemorrhagic complications in cardiac surgery in patients on DOACs.

Direct oral anticoagulants and heparins: laboratory values and pitfalls in 'bridging therapy'.

Objectives: The three direct oral anticoagulants (DOACs) dabigatran, apixaban and rivaroxaban are now widely used in clinical practice. For patients requiring perioperative interruption of DOACs, heparin bridging is still under discussion. Here we show, for the first time, the influence of concomitantly used DOACs and heparins on laboratory assays. Methods: For spiking experiments, 10 healthy donors and nine patients treated with DOACs were investigated. The measurement of DOACs and heparins was performed with routine methods on the ACL TOP [HEMOCLOT ® direct thrombin inhibitor (CoaChrom Diagnostica, Austria), COAMATIC ® Heparin (Chromogenix, USA) calibrated with rivaroxaban, apixaban, unfractionated heparin (UFH) and low molecular weight heparin (LMWH), additionally PT reagent RecombiPlasTin 2G and aPTT reagent SynthASil (Instrumentation Laboratory, Germany)] and the DOACs were additionally quantified with liquid chromatography-mass spectrometry. A linear regression model has been used to estimate the effect of DOAC prestimulation. Results: No influence of dabigatran could be demonstrated in the anti-Xa testing methods for LMWH, UFH, rivaroxaban or apixaban. All FXa-inhibiting drugs affected all the anti-Xa testing methods in their own specific ways. Compared with heparin alone, measurement of heparins in samples with a basic concentration of DOACs (200 ng/ml) displays a more dramatic increase. Samples of patients with therapeutic intake of DOACs spiked with UFH and LMWH showed the expected pharmacokinetic profiles, but increased pharmacodynamic effects. Conclusions: Direct thrombin and FXa inhibitors exhibit distinct effects on assay results when used concomitantly with heparins. These interactions must be considered in the interpretation of assay results during bridging therapy.

The ANISEED database: digital representation, formalization, and elucidation of a chordate developmental program.

Developmental biology aims to understand how the dynamics of embryonic shapes and organ functions are encoded in linear DNA molecules. Thanks to recent progress in genomics and imaging technologies, systemic approaches are now used in parallel with small-scale studies to establish links between genomic information and phenotypes, often described at the subcellular level. Current model organism databases, however, do not integrate heterogeneous data sets at different scales into a global view of the developmental program. Here, we present a novel, generic digital system, NISEED, and its implementation, ANISEED, to ascidians, which are invertebrate chordates suitable for developmental systems biology approaches. ANISEED hosts an unprecedented combination of anatomical and molecular data on ascidian development. This includes the first detailed anatomical ontologies for these embryos, and quantitative geometrical descriptions of developing cells obtained from reconstructed three-dimensional (3D) embryos up to the gastrula stages. Fully annotated gene model sets are linked to 30,000 high-resolution spatial gene expression patterns in wild-type and experimentally manipulated conditions and to 528 experimentally validated cis-regulatory regions imported from specialized databases or extracted from 160 literature articles. This highly structured data set can be explored via a Developmental Browser, a Genome Browser, and a 3D Virtual Embryo module. We show how integration of heterogeneous data in ANISEED can provide a system-level understanding of the developmental program through the automatic inference of gene regulatory interactions, the identification of inducing signals, and the discovery and explanation of novel asymmetric divisions.

C/EBPdelta and C/EBPgamma bind the CCAAT-box in the human beta-globin promoter and modulate the activity of the CACC-box binding protein, EKLF.

Developmental- and tissue-specific expression of globin genes is mediated by a few key elements within the proximal promoter of each gene. DNA-binding assays previously identified NF-Y, GATA-1, C/EBPbeta and C/EBPgamma as candidate regulators of beta-globin transcription via the CCAAT-box, a promoter element situated between CACC- and TATA-boxes. We have identified C/EBPdelta as an additional beta-globin CCAAT-box binding protein. In reporter assays, we show that C/EBPdelta can co-operate with EKLF, a CACC-box binding protein, to activate the beta-globin promoter, whereas C/EBPgamma inhibits the transcriptional activity of EKLF in this assay.