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Factor XI inhibitors: what should clinicians know
Arjun Pandey1, Raj Verma2, John Eikelboom1
1McMaster University, Hamilton ON, Canada.
Purpose Of Review:
Factor XI (FXI) inhibitors were developed to address unmet needs and limitations of current anticoagulants and are currently being studied in several indications. In this paper, we review the rationale for the development of these agents and summarize what clinicians should know about drugs that target FXI.
Recent Findings:
Patients with FXI deficiency may have a lower risk of venous thromboembolism and cardiovascular events and have a variable but generally mild bleeding diathesis. FXI has been proposed as a target for anticoagulants due to the potential for reduction in thrombosis with a lower risk of bleeding than current anticoagulant agents. Several classes of drugs that target FXI are under development, of which three classes (small molecule inhibitors, antisense oligonucleotides and monoclonal antibodies) have been studied in Phase II trials. At least three large Phase III trial programs are planned or are underway, and will study the efficacy and safety of FXI inhibitors in tens of thousands of patients across a variety of indications including atrial fibrillation, stroke and cancer-associated venous thromboembolism.
Summary:
FXI inhibitors were developed with the hope of attenuating thrombosis with reduced bleeding/impairment of haemostasis. These agents have shown promise in preliminary trials with a low rate of bleeding. Ongoing Phase III investigations will inform the utility of these agents in clinical practice.
Insights
New Factor XI (FXI) inhibitors aim to prevent blood clots with less bleeding risk than current anticoagulants. Clinical trials are evaluating their safety and effectiveness for various conditions.
Area of Science:
- Pharmacology
- Hematology
- Cardiovascular Medicine
Background:
- Current anticoagulants carry risks of bleeding and unmet needs in thrombosis treatment.
- Factor XI (FXI) is a potential target for novel anticoagulants due to its role in coagulation.
- FXI deficiency is associated with reduced thrombotic and cardiovascular event risk, and mild bleeding tendencies.
Approach:
- Review of the rationale behind FXI inhibitor development.
- Summary of current clinical knowledge regarding FXI-targeting drugs.
- Overview of ongoing Phase II and planned Phase III clinical trials.
Key Points:
- Several classes of FXI inhibitors, including small molecules, antisense oligonucleotides, and monoclonal antibodies, have advanced to Phase II trials.
- Large-scale Phase III trials are underway or planned for indications such as atrial fibrillation, stroke, and cancer-associated venous thromboembolism.
- Preliminary data suggest FXI inhibitors may offer effective thrombosis prevention with a favorable bleeding profile.
Conclusions:
- FXI inhibitors represent a promising new class of anticoagulants with the potential for reduced bleeding complications.
- Ongoing large-scale clinical trials are crucial to establish the efficacy and safety of FXI inhibitors in diverse patient populations.
- These agents may address significant unmet needs in anticoagulant therapy.
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