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Thrombophilia Testing Summary

Click here for a 2025 summary of thrombophilia testing published by the Anticoagulation Forum.

The Choice of Hemophilia Treatments

Here is a brief and informative editorial that lists current hemophilia Rx choices: Makris M, O’Mahony B. Hemophilia treatments and the paradox of choice. Res Pract Thromb Haemost. 2025;9:102726. doi: 10.1016/j.rpth.2025.102726. PMID: 40224276; PMCID: PMC11992418.

Bleeding Disorders

Antithrombin Assay Supports Fitusiran Therapy

Here’s a link to our 1 April 2025 Sanofi announcement about the FDA approval of Fitusiran® therapy. Sanofi provides the Siemens Healthineers’ INNOVANCE Antithrombin® assay, a chromogenic substrate method, as a companion diagnostic tool to support Fitusiran dosing. A Sanofi-supported study compared eight antithrombin activity assay kits on seven coagulometers to indicate the reagent-instrument combinations […]

Bleeding Disorders

More on Rebalancing Therapy: Suppressing Protein S

Click here for your copy of The World Federation of Hemophilia Shared Decision-making Tool, Hemostatic Rebalancing Therapy. We’ve posted several entries about rebalancing therapy… Pfizer’s Hympavzi® (marstacimab) Anti-TFPI Approved Hemophilia Therapeutics Discontinued Fitusiran Approved March 28, 2025 Fitusiran: A “Rebalancing Agent” Concizumab, A “Rebalancing Agent” August 2024 Quick Question Summary: Rebalancing Therapy Alhemo® (concizumab) Rebalancing […]

Bleeding Disorders

Heparin Resistance in Pancreatitis: Case Report

Click Rongqin D, Zhexin B, Yuzhi L, et al. Heparin resistance in a patient with severe acute pancreatitis: a case report. Lab Med. 2025: lmae126. doi: 10.1093/labmed/lmae126 to access a pre-pub that illustrates a mechanism for heparin resistance in the presence of a normal AT level. Thanks to Margaret G. Fritsma; MA, MLS, SBB for the […]

Does Antiseptic Alcohol Cause Hemolysis?

Collectors routinely disinfect phlebotomy sites with isopropyl alcohol (IPA). We like to repeat a commonly held myth from the “data-free zone” that failure to allow the alcohol to dry before venipuncture causes patient discomfort, blood specimen hemolysis, and blood specimen dilution. The myth is addressed in the attached open access article, Sarmah D, Sharma B, […]

Specimen Management

Underfilled or Overfilled Coagulation Specimen Tubes

The CLSI H21 standard lists causes for coagulation specimen rejection, including hemolysis, icterus, lipemia, clotted specimens, underfilled tubes, and overfilled tubes. In most applications, underfilling is defined as a specimen comprising less than 90% of the stated volume. Most blue-closure tubes contain 0.3 mL of 3.2% sodium citrate and are calibrated to collect 2.7 mL […]

Specimen Management

Chromogenic FX Assay versus PT/INR

Here is an April 1, 2025, “Differential Discussions” webinar hosted by Malissa Norfolk, University of Maine Augusta, and David Cabral, University of Massachusetts Dartmouth. It features my colleague David McGlasson on the subject of “Comparison of the CFX Assay to the INR for Monitoring OAC Therapy.” Thank you to these three hemostasis experts for this […]

Anticoagulant Therapy

Fitusiran Approved March 28, 2025

Thanks to Ali Sadeghi-Khomami, PhD, PBI research scientist, for the following heads-up: On Friday, March 28, 2025, Sanofi Inc. announced the much-awaited approval of fitusiran (Qfitlia®), a “rebalancing” therapeutic that dramatically reduces the ABR in hemophilia A and hemophilia B patients ≥12 YOA with or without inhibitors. Fitusiran is a messenger RNA inhibitor (RNAi) that […]

Bleeding Disorders

Lab Developed Tests Rule

Thanks to PBI’s Dean Willett for his heads-up about the March 31, 2025 ruling, “FDA‘s LDT Rule Struck Down in Texas Court.” The US FDA‘s 2024 “Final Rule” outlined plans to subject lab-developed tests to the same requirements as medical devices. The Texas ruling illustrates the US struggle to achieve a realistic approach to validation […]

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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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