Thrombopoietin receptor agonist switch in adult primary immune thrombocytopenia patients: A retrospective collaborative survey involving 4 Spanish centres.

OBJECTIVE: To describe the reasons for and result of thrombopoietin receptor agonists (TPO-RA) switching in adult immune thrombocytopenia (ITP) patients of 4 Spanish centres.

METHODS: We retrospectively analysed all patients who received sequential treatment with both TPO-RA between 2010 and 2015 recording clinical and biological parameters.

RESULTS: Twenty-six patients were included; 17 received first romiplostim and 9 received first eltrombopag. Reasons for switching were inefficacy (n = 10), patient preference (n = 8), side effects (n = 5) and excessive platelet count fluctuation (n = 3). When the switch was due to inefficacy, 100% of patients who received romiplostim first and 66% who received eltrombopag first responded to the second drug. It is significant that none of the patients who received romiplostim first reached the maximum recommended dose before switching. When the change was due to patient preference or because of side effects, 100% of the patients responded to both TPO-RA. Three patients changed from romiplostim to eltrombopag due to platelet count fluctuation; one did not respond and the fluctuation persisted in the remaining 2 patients. We also found 4 sustained remissions after administering the second TPO-RA, 2 of these with inefficacy of the first drug.

CONCLUSION: TPO-RA switching is a feasible strategy in different scenarios with high probability of success.