Related Experiment Video

Updated: May 23, 2025

Rapid Point-of-Care Assay of Enoxaparin Anticoagulant Efficacy in Whole Blood
11:17

Rapid Point-of-Care Assay of Enoxaparin Anticoagulant Efficacy in Whole Blood

Published on: October 12, 2012

13.7K

Anticoagulant drugs targeting factor XI/XIa and coagulation tests: we urgently need reliable pharmacodynamic data

Isabelle Gouin-Thibault1, Thomas Lecompte2, Dominique Lasne3

  • 1Department of Laboratory Hematology, University Hospital of Rennes, Institut de Recherche en Santé, environnement et travail-INSERM-1085, University of Rennes, Rennes, France.

Journal of Thrombosis and Haemostasis : JTH
|March 8, 2025
PubMed

Insights

New anticoagulants targeting Factor XI/XIa do not need routine monitoring. However, their impact on coagulation tests is not fully understood, necessitating further research for safe clinical use.

Area of Science:

  • Pharmacology
  • Hematology
  • Clinical Chemistry

Background:

  • Antifactor (F)XI/FXIa anticoagulants are emerging therapeutics.
  • These novel anticoagulants include antisense oligonucleotides, monoclonal antibodies, and small molecules.
  • While not requiring routine monitoring, their clinical utility depends on understanding their laboratory effects.

Purpose of the Study:

  • To review the impact of anti-FXI/FXIa anticoagulants on routine coagulation tests.
  • To highlight the need for comprehensive data on these drug-test interactions.
  • To guide the interpretation of coagulation assays in patients treated with these agents.

Main Methods:

  • Review of existing literature on anti-FXI/FXIa anticoagulants and coagulation testing.
  • Analysis of reported effects on activated partial thromboplastin time (aPTT) and other assays.
  • Discussion of challenges in interpreting coagulation tests due to anticoagulant interference.

Main Results:

  • A concentration-dependent prolongation of aPTT is observed, but results vary significantly with different reagents.
  • Measurement of FXI clotting activity is only relevant for antisense oligonucleotide treatments.
  • Contact pathway factor assays require plasma dilution to mitigate anticoagulant interference.

Conclusions:

  • Current data on the effects of anti-FXI/FXIa anticoagulants on coagulation tests are insufficient for widespread clinical interpretation.
  • Standardized methods and comprehensive data are urgently needed to ensure safe and effective use of these drugs post-approval.
  • Further research is essential to establish reliable laboratory monitoring strategies for these novel anticoagulants.
Keywords:
APTTanticoagulantsfactor XI inhibitorsfactor XIa inhibitors

More Related Videos

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay13:08

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay

Published on: September 9, 2012

18.9K
Tail Vein Transection Bleeding Model in Fully Anesthetized Hemophilia A Mice08:13

Tail Vein Transection Bleeding Model in Fully Anesthetized Hemophilia A Mice

Published on: September 30, 2021

5.9K

Related Concept Videos

Anticoagulant Drugs: Vitamin K Antagonists and Direct Oral Anticoagulants01:18

Anticoagulant Drugs: Vitamin K Antagonists and Direct Oral Anticoagulants

Oral anticoagulants are vital tools in preventing and treating blood clotting disorders. This diverse class of medications can be categorized as vitamin K antagonists, exemplified by warfarin, and direct thrombin inhibitors (DTIs), such as dabigatran, as well as factor Xa inhibitors, including rivaroxaban.
Warfarin, a prominent vitamin K antagonist family member, exerts its effect by inhibiting the enzyme VKORC1 (vitamin K epoxide reductase complex 1). By hindering this enzyme, warfarin...
1.1K
Anticoagulant Drugs: Low-Molecular-Weight Heparins01:30

Anticoagulant Drugs: Low-Molecular-Weight Heparins

Hemostasis is a crucial process that prevents excessive blood loss from damaged blood vessels. It involves various mechanisms such as vasoconstriction, platelet adhesion and activation, and fibrin formation. The importance of each mechanism depends on the type of vessel injury. In contrast, thrombosis is the abnormal formation of a blood clot within the blood vessels, leading to potential complications if the clot obstructs blood flow. Thrombosis can be caused by increased coagulability of the...
588
Coagulation01:09

Coagulation

The coagulation phase is a critical part of the body's process to prevent blood loss following injury to blood vessels. It involves chemical reactions that form a clot to seal the injured area. The clotting process begins shortly after injury, within 15-20 seconds for severe damage and 1-2 minutes for minor injuries.
During the coagulation phase, clotting factors, or procoagulants, play a vital role in initiating and progressing the coagulation cascade. This cascade is a series of reactions...
4.0K
Therapeutic Index01:13

Therapeutic Index

The therapeutic index of a drug is a key parameter in pharmacology that quantifies the relative safety of a drug by calculating the ratio between the dose that causes toxicity in half the population (50%) to the dose that proves to be effective for half the population (50%). It provides a spectrum of doses for a particular drug ranging from effective to potentially toxic. To illustrate, consider an anticoagulant agent like warfarin. It possesses a narrow window within its therapeutic index to...
4.0K
Extrinsic and Intrinsic Pathways of Hemostasis01:20

Extrinsic and Intrinsic Pathways of Hemostasis

Blood clotting or coagulation involves extrinsic and intrinsic pathways, which ultimately merge into the common pathway, forming a fibrin clot.
The Extrinsic Pathway
The extrinsic pathway of coagulation is typically initiated by tissue damage that exposes blood to tissue factor (TF), a protein released by the damaged tissue cells outside the blood vessels—this interaction with TF triggers biochemical reactions involving specific clotting factors. The key player here is Factor VII, which...
4.6K
Clot Retraction and Fibrinolysis01:16

Clot Retraction and Fibrinolysis

After a fibrin clot is formed, the next step is clot retraction, a vital process facilitated by platelet contractile proteins, such as actin and myosin. These proteins pull the fibrin strands closer together and condense the clot. This action reduces the size of the clot, creating a smaller, denser structure that effectively seals off the damaged vessel. Clot retraction consolidates the clot and helps with wound healing by bringing the edges of the damaged blood vessel closer together.
3.2K