From the Research
The optimum antithrombin level in patients receiving Chimeric Antigen Receptor T (CAR-T) cell therapy should be maintained above 70-80% to prevent thrombotic complications, as supported by the most recent and highest quality study available 1.
Background
CAR-T cell therapy is a promising treatment for hematological malignancies, but it can lead to a prothrombotic state, increasing the risk of thrombotic complications. Antithrombin deficiency is a common issue in these patients, often due to consumption during cytokine release syndrome (CRS) or immune effector cell-associated neurotoxicity syndrome (ICANS), as well as from concurrent infections or disseminated intravascular coagulation.
Management
For patients with low antithrombin levels, antithrombin concentrate (AT III) should be administered at 50-100 IU/kg IV, with dosing adjusted based on patient weight and baseline antithrombin levels. Subsequent doses should be guided by laboratory monitoring, typically every 12-24 hours during acute phases of treatment. Maintaining adequate antithrombin levels is crucial because CAR-T therapy creates a prothrombotic state, and sufficient antithrombin ensures proper anticoagulation efficacy if heparin products are needed.
Considerations
For patients with persistent antithrombin deficiency despite replacement, consider underlying causes such as liver dysfunction or ongoing consumption, and adjust the replacement strategy accordingly with more frequent dosing or higher doses as needed. The most recent study available 1 highlights the importance of careful management of antithrombin levels in CAR-T cell therapy patients to prevent thrombotic complications and ensure optimal outcomes.
Key Points
- Maintain antithrombin levels above 70-80% to prevent thrombotic complications
- Administer antithrombin concentrate (AT III) at 50-100 IU/kg IV for patients with low antithrombin levels
- Adjust dosing based on patient weight and baseline antithrombin levels
- Monitor laboratory results every 12-24 hours during acute phases of treatment
- Consider underlying causes of persistent antithrombin deficiency and adjust replacement strategy accordingly