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 review examined anticoagulation strategies for cancer-associated thrombosis (CAT), discussing low molecular weight heparins (LMWH) as the established standard of care and summarizing randomized trials comparing direct oral anticoagulants (DOACs) — specifically the factor Xa inhibitors apixaban, rivaroxaban, and edoxaban — against placebo for prophylaxis and against LMWH for treatment, finding non-inferior efficacy but increased bleeding risk, particularly in gastrointestinal cancers. For hirudotherapy and ASH, this review provides relevant background on the broader clinical anticoagulant landscape and the persistent challenge of balancing antithrombotic efficacy against bleeding — a fundamental pharmacodynamic tension also central to hirudin-based agents derived from the medicinal leech secretome. Understanding how contemporary anticoagulants perform in high-risk cancer populations offers useful comparative context for leech-derived therapies. However, the review does not specifically address hirudin, lepirudin, desirudin, or other direct thrombin inhibitors, so the leech-therapy connection is indirect rather than explicit.

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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