Drug-drug interactions: Implications for anticoagulation, with focus in patients with cancer

Patients with cancer have increased risks of venous and arterial thromboembolism and/or atrial fibrillation, for which anticoagulation is commonly used. For these indications, three main types of anticoagulants are recommended or used: low-molecular-weight heparin (LMWH), direct oral anticoagulants (DOACs), and vitamin K antagonists (VKAs), all have different advantages and disadvantages. Drug-drug interactions (DDIs) with anticoagulation are often cautioned against by major guidelines, but evidence remains scarce regarding the best management approach for specific drug combinations, particularly with DOACs. Significant DDIs might affect the efficacy and safety of anticoagulants and/or anticancer therapies as well as other interfering medications, and more studies are needed. This paper will review the available evidence and guidelines on DDIs with anticoagulants, focusing on the cancer population whenever possible, and propose directions for future research.