Durability of Response to Eltrombopag in Chronic Immune Thrombocytopenia: A Five-Year Cohort

Bystrik Ondris; D. Palenik; C. Weisz

doi:10.5281/zenodo.22818788

Authors

Bystrik Ondris Department of Transfusion Medicine and Blood Banking, Olt Institute of Hematologic Diagnostics Author https://orcid.org/3128-2641-5011-2811
D. Palenik Department of Hematology, Aare Institute of Hematopathology Author https://orcid.org/3525-3500-1341-9933
C. Weisz Department of Laboratory Hematology, Mures Institute of Blood Cancer Genetics Author https://orcid.org/5903-2078-1764-5905

DOI:

https://doi.org/10.5281/zenodo.22818788

Keywords:

eltrombopag, immune thrombocytopenia, thrombopoietin receptor agonist, durability of response, romiplostim

Abstract

Graphical abstract

Background: Thrombopoietin receptor agonists are a mainstay of second-line therapy for chronic immune thrombocytopenia (ITP), and eltrombopag now carries the longest continuous follow-up of any oral agent in the class, though no single prospective cohort spans a full five-year horizon.

Objective: To synthesize the pivotal trial and long-term extension-study literature on eltrombopag in chronic ITP and characterize what it says about durability of platelet response over years rather than weeks.

Methods: Narrative synthesis of placebo-controlled registration trials, open-label extension studies (including EXTEND), discontinuation cohorts, and comparative studies against romiplostim.

Findings: Once established within one to two months, platelet response is maintained for years in most responders; splenectomy status is the most consistent modifier of response and durability; loss of response after initial success is uncommon and non-progressive; and a minority of complete responders sustain normal counts after withdrawal.

Conclusions: Eltrombopag is a durable long-term option in chronic ITP with a monitoring burden distinct from, but durability broadly comparable to, romiplostim; the open question is less whether response persists and more whether its dosing and monitoring remain acceptable for however long that response holds.

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