Background: Thrombopoietin receptor agonists (TPO-RAs) are used to treat primary immune thrombocytopenia (ITP). Some patients have discontinued treatment while maintaining a hemostatic platelet count.
Objectives: To develop expert consensus on when it is appropriate to consider tapering TPO-RAs in ITP, how to taper patients off therapy, how to monitor patients after discontinuation, and how to restart therapy.
Methods: We used a RAND/UCLA modified Delphi panel method. Ratings were completed independently by each expert before and after a meeting. Second-round ratings were used to develop the panel's guidance. The panel was double-blinded: The sponsor and nonchair experts did not know each other's identities.
Results: Guidance on when it is appropriate to taper TPO-RAs in children and adults was developed based on patient platelet count, history of bleeding, intensification of treatment, trauma risk, and use of anticoagulants/platelet inhibitors. For example, it is appropriate to taper TPO-RAs in patients who have normal/above-normal platelet counts, have no history of major bleeding, and have not required an intensification of treatment in the past 6 months; it is inappropriate to taper TPO-RAs in patients with low platelet counts. Duration of ITP, months on TPO-RA, or timing of platelet response to TPO-RA did not have an impact on the panel's guidance on appropriateness to taper. Guidance on how to taper patients off therapy, how to monitor patients after discontinuation, and how to restart therapy is also provided.
Conclusion: This guidance could support clinical decision making and the development of clinical trials that prospectively test the safety of tapering TPO-RAs.
Keywords: blood platelets; consensus; idiopathic; platelet count; purpura; receptors; thrombocytopenic; thrombopoietin.
© 2020 The Authors. Research and Practice in Thrombosis and Haemostasis published by Wiley Periodicals LLC on behalf of International Society on Thrombosis and Haemostasis.