Key result
Remdesivir is linked to marked INR elevation in patients on stable warfarin therapy.
Why the study?
There was no published literature documenting interaction between warfarin and remdesivir despite potential clinical significance.
Does concomitant administration of remdesivir and warfarin increase INR in patients on long-term anticoagulation?
Case Report (n=1)
Does concomitant administration of remdesivir and warfarin increase INR in patients on long-term anticoagulation?
This first reported case of a probable remdesivir-warfarin interaction highlights the need for close INR monitoring when these drugs are co-administered to prevent excessive anticoagulation.
May warrant INR monitoring with remdesivir in warfarin users; leaves open confirmation of interaction in larger studies.
Description A greater than 65-year-old Caucasian woman receiving long-term anticoagulation with warfarin for atrial fibrillation experienced a sudden rise in an international normalized ratio (INR) after she was started on remdesivir for management of 2019 Novel Coronavirus (COVID-19). Patient INR was maintained within the target therapeutic range of 2-3 with a warfarin dose of 11 mg/week before starting remdesivir. After 2 days of remdesivir therapy, the patient's INR increased significantly and remained elevated during the 5 day course of remdesivir therapy. Patient required an interruption of her warfarin therapy for 7 days, and her INR did not return to the targeted therapeutic INR range of 2-3 until day 5 from the last dose of remdesivir, despite no warfarin administration. A comprehensive PubMed/MEDLINE search did not find published literature documenting interaction between warfarin and remdesivir. We describe the first case report, to our knowledge, documenting a potential drug interaction between warfarin and remdesivir. The authors found that there is a probable interaction between warfarin and remdesivir when applying the Adverse Drug Reaction Probability Scale, Naranjo Scale. To reduce the risk of bleeding associated with excessive anticoagulation, clinicians should closely monitor INR, and adjust the warfarin dose accordingly when patients are receiving remdesivir and warfarin concomitantly.
No takes yet. Share an insight, caveat, or question.
Manigaba et al. (2020) conducted a case report in COVID-19 and atrial fibrillation (n=1). Remdesivir was evaluated on INR elevation. Concomitant administration of remdesivir in a patient on stable warfarin therapy resulted in a significant and prolonged elevation of INR, indicating a probable drug interaction.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: