American Society of Hirudotherapy

An update on the efficacy and safety of novel anticoagulants for cancer associated thrombosis

Research article published in Expert opinion on pharmacotherapy (2021)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Narrative reviewClinical TrialsCosmi · Expert opinion on pharmacotherapy, 2021

Abstract

Introduction: Cancer-associated thrombosis (CAT) refers to the most common thromboembolic complication of cancer which is venous thromboembolism (VTE). CAT primary prophylaxis, treatment, and secondary prevention are challenging for the complexity of cancer patients, who exhibit hypercoagulability with concomitant-heightened bleeding risk.Areas covered: In this review, the author examines the role of low molecular weight heparins (LMWH), which have been the standard of care for CAT treatment for many years. Direct oral anticoagulants (DOACS) have practical advantages over subcutaneous LMWH, especially for long-term therapy. The author then discusses the results of two RCTs which separately compared the direct oral factor Xa inhibitors, apixaban or rivaroxaban, with placebo for CAT prophylaxis in ambulatory high-risk cancer patients and found that DOACS reduced VTE but increased bleeding. Finally, the author discusses four RCTS separately comparing an oral direct factor Xa inhibitor (edoxaban, rivaroxaban, or apixaban) with LMWH for CAT treatment. DOACS showed non-inferior efficacy, although rivaroxaban and edoxaban showed higher bleeding rates, especially in gastrointestinal cancers.Expert opinion: DOACS have a convenient route of administration and do not require laboratory monitoring, although choice of anticoagulants for CAT depends on factors such as tumor type, bleeding risk, concomitant drugs, and comorbidities.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal ArticleReview
Indexed MeSH termsAdministration, OralAnticoagulantsHeparin, Low-Molecular-WeightHumansNeoplasmsThrombosisVenous Thromboembolism

Summary

Peer-reviewed clinical and outcomes research relevant to medicinal leech therapy and its biology. Indexed in PubMed and verified against the NCBI record.

Why This Matters for Hirudotherapy

This narrative review summarizes the efficacy and safety of low-molecular-weight heparins versus direct oral anticoagulants (the factor Xa inhibitors apixaban, rivaroxaban, and edoxaban) for cancer-associated thrombosis, noting that across the RCTs it surveys the direct oral agents showed non-inferior efficacy but rivaroxaban and edoxaban carried higher bleeding rates, especially in gastrointestinal cancers, so anticoagulant choice should be individualized. Its ASH relevance is as a clear map of the anticoagulation landscape, the coagulation-modulation field in which the medicinal-leech secretome's thrombin-inhibiting peptides are the historical antecedent of today's targeted anticoagulants. The caveat is that this is a review synthesizing other authors' trials rather than original data, it reflects the cited author's interpretation and the evidence available up to 2021, and it concerns conventional drugs with no leech-derived agent or hirudotherapy in scope.

Citation

An update on the efficacy and safety of novel anticoagulants for cancer associated thrombosis.

Cosmi · Expert opinion on pharmacotherapy, 2021

Added to ASH library: May 29, 2026 · Site last updated: June 18, 2026

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