Thrombopoietin-Receptor Agonism in Chemotherapy-Induced Thrombocytopenia

Abstract

Chemotherapy-induced thrombocytopenia (CIT) is a common, dose-limiting toxicity of cytotoxic cancer therapy that frequently necessitates dose reduction, delay, or discontinuation, thereby compromising relative dose intensity and potentially diminishing therapeutic efficacy. Existing management strategies are largely supportive and do not address the underlying defect in thrombopoiesis. Romiplostim, a thrombopoietin-receptor agonist, directly stimulates megakaryocyte proliferation and platelet production. In prospective phase II studies and multicenter real-world cohorts, romiplostim has consistently demonstrated rapid and sustained platelet recovery in the majority of patients with CIT, enabling timely continuation of chemotherapy without recurrent thrombocytopenia and substantially reducing the need for platelet transfusions. Available evidence indicates an acceptable safety profile, with no clear excess in thrombotic events or cumulative marrow toxicity beyond that expected in patients with active malignancy. However, these findings are derived predominantly from phase II and observational data, and important uncertainties remain regarding predictors of response and optimal dosing strategies. Romiplostim represents a rational, mechanism-based approach to CIT with the potential to preserve chemotherapy delivery and treatment intensity; adequately powered randomized trials are required to define its role in routine oncologic practice.