Recent Advances in Anticoagulant Treatment of Immune Thrombosis: A Focus on Direct Oral Anticoagulants in Heparin-Induced Thrombocytopenia and Anti-Phospholipid Syndrome

For more than 10 years, direct oral anticoagulants (DOACs) have been increasingly prescribed for the prevention and treatment of thrombotic events. However, their use in immunothrombotic disorders, namely heparin-induced thrombocytopenia (HIT) and antiphospholipid syndrome (APS), is still under investigation. The prothrombotic state resulting from the autoimmune mechanism, multicellular activation, and platelet count decrease, constitutes similarities between HIT and APS. Moreover, they both share the complexity of the biological diagnosis. Current treatment of HIT firstly relies on parenteral non-heparin therapies, but DOACs have been included in American and French guidelines for a few years, providing the advantage of limiting the need for treatment monitoring. In APS, vitamin K antagonists are conversely the main treatment (+/- anti-platelet agents), and the use of DOACs is either subject to precautionary recommendations or is not recommended in severe APS. While some randomized controlled trials have been conducted regarding the use of DOACs in APS, only retrospective studies have examined HIT. In addition, vaccine-induced immune thrombotic thrombocytopenia (VITT) is now a part of immunothrombotic disorders, and guidelines have been created concerning an anticoagulant strategy in this case. This literature review aims to summarize available data on HIT, APS, and VITT treatments and define the use of DOACs in therapeutic strategies.

Automated summary

DOACs have been increasingly prescribed for more than 10 years for the prevention and treatment of thrombotic events. However, their use in immunothrombotic disorders, such as HIT and APS, is still under investigation. HIT and APS share similarities in terms of autoimmune mechanism, multicellular activation, and platelet count decrease. DOACs have been included in guidelines for the treatment of HIT, but their use in APS is either subject to precautionary recommendations or not recommended in severe cases. Limited studies have been conducted on the use of DOACs in APS and HIT, with most being retrospective in nature. VITT, as a newly recognized immunothrombotic disorder, also has specific guidelines for anticoagulant strategies.