How to Identify PK or HMWK Deficiency

Here is a paraphrase of a question I (Geo) received on 4-3-26: “We recently evaluated a patient with an isolated prolonged APTT that corrected on mixing study. The patient has no history of bleeding and no significant family history of bleeding disorders. FVIII, FIX, FXI, and FXII assays were within normal limits. In view of […]

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Bleeding Disorders

Mar 22 2026

george

Case Study: VWF Inhibitors in Brothers

This open-access article describes inhibitor formation in two brothers who were subjects in a Wilate® study: Djambas Khayat C, Pavlova A, Werner S, Knaub S, Sidonio RF Jr. von Willebrand factor (VWF) inhibitors in two brothers with von Willebrand disease: a case report. TH Open. 2025;9:a26069625. doi: 10.1055/a-2606-9625. PMID: 40673043; PMCID: PMC12265396. Abstract The development […]

Bleeding Disorders

Meta-analysis: BAT in VWD Dx

At the March 18–21, 2026 THSNA meeting in Portland, Oregon, USA, there were several oral and poster presentations on VWD symptoms, management, and laboratory diagnosis and monitoring. Here is an open-access meta-analysis on BAT efficacy in VWD: Kalot MA, Husainat N, Tayiem S, et al. Bleeding assessment tools in the diagnosis of VWD in adults […]

Bleeding Disorders

Effects of Platelet Transfusions on Neonates

Check your medical library for this article that describes levels of morbidity and mortality of neonates receiving platelet transfusions: Davenport P, Feldman HA, Young V, et al. Effects of platelet transfusions on neonatal bleeding and inflammation. Pediatr Res. 2025 Nov 5. doi: 10.1038/s41390-025-04498-9. Erratum in: Pediatr Res. 2025 Dec 2. doi: 10.1038/s41390-025-04676-9. PMID: 41193819. Abstract […]

Bleeding Disorders

Phase 3 Clinical Trial Results Indicate Efficacy of Marstacimab in Hemophilia A & B With Inhibitors

Click here for the open-access results of the anti-TFPI MOAB rebalancing therapy marstacimab (HYMPAVZI®): Matino D, Acharya SS, Taylor CT, et al. Efficacy and safety of marstacimab prophylaxis in hemophilia A/B with inhibitors: results from the phase 3 BASIS trial. Blood. 2026;147:920–31. doi: 10.1182/blood.2025031065. PMID: 41351884. Abstract Marstacimab, a monoclonal antibody that inhibits tissue factor […]

Bleeding Disorders

Review: Acquired Hemostasis Disorders

See this open-access review on acquired hemostasis disorders: Tufano A, Franchini M, Coppola A. Acquired hemostasis disorders. Semin Thromb Hemost. 2026;52:277–9. doi: 10.1055/a-2788-1844. PMID: 41802449.

Bleeding Disorders

BioMarin Withdraws Roctavian

This announcement appears in BioMarin’s 2025 full-year financial report: “Following the company’s October announcement to explore options to divest ROCTAVIAN, BioMarin undertook a comprehensive effort to identify a potential buyer. Despite these efforts, BioMarin was unable to identify a qualified buyer and has decided to withdraw ROCTAVIAN from the market voluntarily.” There are no FVIII […]

Bleeding Disorders

Emicizumab Dosage

Here is an open-access article on current emicizumab dosage: van der Zwet K, de Vos ADW, Cnossen MH, et al; OPTI-CLOT Study Group and SYMPHONY Consortium. Pharmacokinetic-guided dose reduction of emicizumab in congenital hemophilia A: interim analysis of the DosEmi study. J Thromb Haemost. 2026;24:890–99. doi: 10.1016/j.jtha.2025.10.029. PMID: 41207564. Abstract Background Emicizumab provides effective prophylaxis […]

Bleeding Disorders

Case Series: Emicizumab Therapy in Acquired Hemophilia A

Here is an open-access article describing emicizumab Rx in acquired hemophilia A: Calcaterra I, De Luca C, D’Errico G, et al. Emicizumab in acquired hemophilia A: a real-world case series with patient-level outcome analysis. Semin Thromb Hemost. 2026 doi: 10.1055/a-2788-1642. Epub ahead of print. PMID: 41534873. Abstract Acquired Hemophilia A (AHA) is a rare bleeding […]

Bleeding Disorders

Field Study Compares OSA With CSA for Measuring Efanesoctocog Alfa

Here is an open-access article contrasting the validity of OSA versus CSA for measuring efanesoctocog alfa (Altuviiio®) spiked into normal plasma: Pipe S, Sadeghi-Khomami A, Konkle BA, et al. A global comparative field study to evaluate the factor VIII activity of efanesoctocog alfa by one-stage clotting and chromogenic substrate assays at clinical haemostasis laboratories. Haemophilia. […]

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Factor Assays

Bleeding Disorders

How to Identify PK or HMWK Deficiency

Case Study: VWF Inhibitors in Brothers

Meta-analysis: BAT in VWD Dx

Effects of Platelet Transfusions on Neonates

Phase 3 Clinical Trial Results Indicate Efficacy of Marstacimab in Hemophilia A & B With Inhibitors

Review: Acquired Hemostasis Disorders

BioMarin Withdraws Roctavian

Emicizumab Dosage

Case Series: Emicizumab Therapy in Acquired Hemophilia A

Field Study Compares OSA With CSA for Measuring Efanesoctocog Alfa

George Fritsma MS MLS

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