How I treat chemotherapy-induced thrombocytopenia with thrombopoietin receptor agonists.

Chemotherapy-induced thrombocytopenia (CIT) is a common complication of cancer therapy that may result in major bleeding events and reduction of chemotherapy relative dose intensity. Although there remain no widely available licensed therapies to manage CIT, major studies, including global pivotal phase 3 clinical trials of the thrombopoietin receptor agonists (TPO-RAs) romiplostim and avatrombopag in CIT, have been completed, along with additional supporting evidence from other clinical trials and observational studies. As with patients with chemotherapy-induced neutropenia, not all patients with CIT require treatment, but for those who do, it can have a major impact on a patient's oncologic care and outcomes. Proper management of CIT requires an understanding of the 2 clinical subtypes of CIT (persistent and nadir), the limited role of platelet transfusions and antifibrinolytics, and when and how to appropriately use TPO-RA support. In this article, 4 patient cases of CIT are used to illustrate common and challenging scenarios occurring in clinical practice. Built on a framework of published studies and supported by extensive clinical experience, appropriate treatment strategies for CIT are described in detail, with emphasis on proper selection of patient, dosing, titration, and monitoring for the use of TPO-RAs in CIT.