Bleeding Disorders

August 2024 Quick Question: Hemophilia Treatment

Several hemophilia A or B treatments are in development or have been approved since 2021. Among these are the “rebalancing” preparations that suppress control proteins such as tissue factor pathway inhibitor (TFPI), antithrombin (AT), or activated protein C (APC). Rebalancing preparations are designed to compensate for the bleeding tendencies in FVIII or FIX deficiency without […]

Bleeding Disorders

Low Titer Group O Whole Blood in Trauma

Click here for a July 2024 CAP Today article describing the growing use of low titer group O whole blood in trauma and emergencies and its effect on trauma-induced coagulopathy.

Bleeding Disorders

Bioengineered FVIII: efanestocog alfa

Here is a richly illustrated open-access editorial of the development and physiologic function of efanesoctocog alfa (Altuviiio®, Sanofi), which features a half-life 4X that of current concentrates: Chowdary P. Bioengineered factor VIII–more innovation for Hemophilia A. N Engl J Med. 2024;391:277–82. doi: 10.1056/NEJMe2313795. PMID: 39018538.

Bleeding Disorders

Concizumab, A “Rebalancing Agent”

Below is the abstract of a 2019 presentation by Amy Shapiro MD, CEO and co-medical director of the Indiana Hemophilia & Thrombosis Center in Indianapolis, Indiana, USA, describing the rebalancing agent concizumab, approved as Alhemo® by Health Canada in March 2023 but rejected by the US FDA on May 5, 2023, with a request for […]

Bleeding Disorders

Fitusiran: A “Rebalancing Agent”

Fitusiran is an inhibitory double-stranded RNA (RNAi, also called small interfering RNA, siRNA). Fitusiran, termed a “rebalancing agent,” suppresses the nuclear production of antithrombin (AT) messenger RNA (mRNA). AT is a major coagulation control protein that binds and disables thrombin and FXa (also FIXa and FXIa to a lesser extent). By suppressing AT production, fitusiran […]

Bleeding Disorders

June 2024 QQ Poll Summary: OSA and Chromogenics

Our June 2024 Quick Question attracted 18 responses. This month’s Question was a poll that asked, “How do you assay factor concentrates?” Here are our answers: Clot-based assay: 11 [61%] Chromogenic substrate assay: 4 [22%] Other: 3 [17%] Factor assays are most often requested to monitor hemophilia factor concentrate activity for patient-specific efficacy and the […]

VWD in Nigeria: Request for Proposal

Hello George. I am reaching out from my research institute as we are planning to apply for a grant from the Wellcome Trust. Our project title is “Comprehensive Characterization Of von Willebrand’s Disease in Nigeria; Closing the Gap in Global Bleeding Disorders.” As a collaborator, you will be asked to support the delivery of the […]

Bleeding Disorders

June 2024 QQ: Factor Assays

Our June 2025 Quick Question is a poll that asks, “How do you assay factor concentrates?” The question reflects the current hemostasis laboratory efforts to quantify therapeutic FVIII or FIX concentrate activity given the variety of plasma-based, recombinant, B-domain-deleted, and extended half-life therapeutics. We also manage factor concentrates that are employed to control breakthrough bleeds […]

Quick Question Archive

May 2024 QQ Summary: Platelet Transfusion Trigger

Our May 2024 Quick Question was a survey that asked, “Below what PLT count limit do you provide PLT concentrate?” our 25 participants answered as follows: <150,000/uL: 2 [8%] <50,000/uL: 3 [12%] <20,000/uL: 7 [28%] <10,000/uL: 13 [52%] <5,000/uL: 0 The correct answer is “it depends.” Current WHO platelet concentrate transfusion guidelines are available at […]

Quick Question Archive

Marstacimab Anti-TFPI Moab Submitted for FDA and EMA Approval

Pfizer has applied to the US FDA and the European Medicines Agency [EMA] for approval of their monoclonal antibody anti-tissue factor pathway inhibitor [TFPI] therapeutic, marsticimab, a competitor to Novo Nordisk’s concizumab, approved by Health Canada under the trademark Alhemo®, and awaiting FDA and EMA approval. The FDA anticipates an FDA ruling in the fourth […]

Bleeding Disorders

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George Fritsma is a medical laboratory scientist, educator, and author. George holds faculty appointments with Rutgers University and Michigan State University, and is a member of the International Society on Thrombosis and Hemostasis, American Association of Clinical Chemists, and American Society for Clinical Laboratory Science.

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