Publications by authors named "John Curnutte"

Article Synopsis
  • The study compares 30-day mortality rates between two anticoagulant reversal agents: andexanet alfa and prothrombin complex concentrate (PCC) in patients experiencing direct-acting oral anticoagulant (DOAC)-related bleeds.
  • Patients in the ANNEXA-4 trial receiving andexanet alfa had a significantly lower adjusted 30-day mortality rate (14.6%) compared to patients treated with PCC (34.1%), especially in those with intracranial hemorrhage (ICH).
  • The findings suggest that andexanet alfa may be more effective in reducing mortality in these cases, but the study also notes limitations due to unaccounted variables, indicating a need for further research.
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Background And Purpose: Andexanet alfa is a recombinant modified human FXa (factor Xa) developed to reverse FXa inhibition from anticoagulants. Hemostatic efficacy and reversal of anti-FXa activity with andexanet were assessed in patients from the ANNEXA-4 study (Andexanet Alfa, a Novel Antidote to the Anticoagulation Effects of FXa Inhibitors) with intracranial hemorrhage (ICrH).

Methods: ANNEXA-4 was a single-arm study evaluating andexanet in patients presenting with major bleeding ≤18 hours after taking an FXa inhibitor.

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Background: Andexanet alfa (andexanet) is a modified human factor Xa (FXa) approved for anticoagulation reversal in patients with life-threatening bleeding treated with rivaroxaban or apixaban. Four-factor prothrombin complex concentrates (4F-PCCs) are approved for reversal of vitamin K antagonist-induced anticoagulation but not FXa inhibitors. The mechanism and effectiveness of 4F-PCCs for FXa inhibitor reversal are unclear.

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As with any anticoagulant, factor Xa (FXa) inhibitors are associated with a risk of major bleeding. Andexanet alfa is a recombinant modified human FXa lacking enzymatic activity, developed for reversal of FXa inhibitor-induced anticoagulation. In two phase 2, randomized, double-blind, placebo-controlled, single-center studies, different regimens of andexanet alfa were administered to healthy volunteers after therapeutic anticoagulation with rivaroxaban or edoxaban, and multiple anticoagulation reversal and safety end points were evaluated.

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Background: Manual segmentations of intracranial hemorrhage on non-contrast CT images are the gold-standard in measuring hematoma growth but are prone to rater variability.

Aims: We demonstrate that a convex optimization-based interactive segmentation approach can accurately and reliably measure intracranial hemorrhage growth.

Methods: Baseline and 16-h follow-up head non-contrast CT images of 46 subjects presenting with intracranial hemorrhage were selected randomly from the ANNEXA-4 trial imaging database.

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Background: Andexanet alfa is a modified recombinant inactive form of human factor Xa developed for reversal of factor Xa inhibitors.

Methods: We evaluated 352 patients who had acute major bleeding within 18 hours after administration of a factor Xa inhibitor. The patients received a bolus of andexanet, followed by a 2-hour infusion.

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Purpose: Preclinical studies suggest SYK and JAK contribute to tumor-intrinsic and microenvironment-derived survival signals. The pharmacodynamics of cerdulatinib, a dual SYK/JAK inhibitor, and associations with tumor response were investigated.

Patients And Methods: In a phase I dose-escalation study in adults with relapsed/refractory B-cell malignancies, cerdulatinib was administered orally to sequential dose-escalation cohorts using once-daily or twice-daily schedules.

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Introduction: Increasing use of factor Xa (FXa) inhibitors necessitates effective reversal agents to manage bleeding. Andexanet alfa, a novel modified recombinant human FXa, rapidly reverses the anticoagulation effects of direct and indirect FXa inhibitors.

Objective: To evaluate the ability of andexanet to reverse anticoagulation in vitro and reduce bleeding in rabbits administered edoxaban.

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Direct factor Xa (FXa) inhibitors lack a specific reversal agent for emergencies such as major bleeding or urgent surgery. Andexanet alfa, a modified, catalytically inactive, recombinant human FXa derivative, reverses anticoagulant effect by binding and sequestering FXa inhibitors. This original report of safety and dose-finding, phase 1 and 2 randomized, double-blind, placebo-controlled studies, investigated various doses of andexanet in healthy volunteers.

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Background: Andexanet alfa (andexanet) is a recombinant modified human factor Xa decoy protein that has been shown to reverse the inhibition of factor Xa in healthy volunteers.

Methods: In this multicenter, prospective, open-label, single-group study, we evaluated 67 patients who had acute major bleeding within 18 hours after the administration of a factor Xa inhibitor. The patients all received a bolus of andexanet followed by a 2-hour infusion of the drug.

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Background: Bleeding is a complication of treatment with factor Xa inhibitors, but there are no specific agents for the reversal of the effects of these drugs. Andexanet is designed to reverse the anticoagulant effects of factor Xa inhibitors.

Methods: Healthy older volunteers were given 5 mg of apixaban twice daily or 20 mg of rivaroxaban daily.

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This white paper provides a summary of presentations and discussions that were held at an Anticoagulant-Induced Bleeding and Reversal Agents Think Tank co-sponsored by the Cardiac Safety Research Consortium and the US Food and Drug Administration (FDA) at the FDA's White Oak Headquarters on April 22, 2014. Attention focused on a development pathway for reversal agents for the novel oral anticoagulants (NOACs). This is important because anticoagulation is still widely underused for stroke prevention in patients with atrial fibrillation.

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Chronic granulomatous disease (CGD) is a primary immunodeficiency of defective neutrophil oxidative burst activity due to mutations in the genes CYBA, NCF-1, NCF-2, and CYBB, which respectively encode the p22-phox, p47-phox, p67-phox, and gp91-phox subunits. CGD usually presents in early childhood with recurrent or severe infection with catalase-positive bacteria and fungi. We present an unusual case of CGD in which Burkholderia cepacia lymphadenitis developed in a previously healthy 10-year-old girl.

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Chronic granulomatous disease (CGD) is a rare inherited disorder in which antimicrobial activity of phagocytes is impaired due to the lack of reactive oxygen species, or oxidative burst, produced by NADPH oxidase. The X-linked form of CGD, representing approximately 70% of all cases, is caused by mutations in the cytochrome b beta subunit (CYBB) gene, which maps to chromosome Xp21.1.

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It was 32 years ago that Bernard Babior, Ruby Kipnes, and I submitted a paper to the JCI reporting that polymorphonuclear leukocytes produce superoxide (O(2) (-)) during phagocytosis and that this highly reactive oxygen radical might function as a microbicidal agent. The story of how our lab came to this discovery is one of a special relationship between a student and his brilliant mentor.

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We describe 2 cases of autosomal recessive chronic granulomatous disease (CGD) in 2 sisters presenting with a picture consistent with inflammatory bowel disease. The index case is a 10-year-old girl with a history of refractory Crohn's colitis treated with aggressive immunosuppressive therapy whose course subsequently was complicated by central nervous system aspergillosis. Additional evaluation showed a diagnosis of CGD, an underlying immunodeficiency in which phagocytes fail to produce microbicidal reactive oxygen intermediates because of inherited defects in the reduced form of nicotinamide-adenine phosphate dinucleotide (NADPH) oxidase.

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Chronic granulomatous disease (CGD) is a primary immunodeficiency that affects phagocytes of the innate immune system and is characterized by a greatly increased susceptibility to severe bacterial and fungal infections. CGD is caused by mutations in any one of four genes that encode the subunits of phagocyte NADPH oxidase, the enzyme that generates microbicidal (and pro-inflammatory) oxygen radicals. Of the 410 CGD mutations identified, 95% cause the complete or partial loss of protein and provide little information regarding the relationship between protein structure and function.

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Chronic granulomatous disease is a neutrophil disorder in which phagocytic cells fail to produce a respiratory burst. Five genetic types of chronic granulomatous disease have been described and in each case the clinical manifestations relate to the inability to effectively kill catalase-positive organisms. It is classically described as a pure disorder of intracellular killing, with preservation of other aspects of phagocytic function such as migration and phagocytosis and normal function of nonmyeloid cells.

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This study defines the molecular basis for defects in innate immunity involving neutrophils during cecal ligation/puncture (CLP)-induced sepsis in rats. Blood neutrophils from CLP rats demonstrated defective phagocytosis and defective assembly of NADPH oxidase, the latter being due to the inability of p47(phox) to translocate from the cytosol to the cell membrane of neutrophils after cell stimulation by phorbol ester (PMA). The appearance of these defects was prevented by in vivo blockade of C5a in CLP rats.

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