Eltrombopag for the Treatment of Poor Graft Function Following Haematopoietic Cell Transplantation: Real-Life Data.

Background: Eltrombopag has an off-label indication for haematopoietic cell transplantation in patients experiencing delayed thrombocyte recovery and/or thrombocytopaenia.

Aims: To present our centre’s experience of using this agent not only for post- haematopoietic cell transplantation thrombocytopaenia but also for poor graft functioning in the post-haematopoietic cell transplantation setting.

Study Design: Retrospective cross-sectional study.

Methods: Thirty-nine patients who had persistent cytopaenia following haematopoietic cell transplantation and treated with eltrombopag at our centre between October 2011 and December 2021 were retrospectively identified. During this period, 9 (23.1%) and 30 (76.9%) patients who underwent allogeneic transplantations, respectively, received eltrombopag.

Results: The female-to-male ratio was 12:27, and the median transplant age was 49 (18-70) years. Eight (20.5%) patients had isolated thrombocytopaenia, 19 (49.4%) had bi-lineage cytopaenia and 12 (30.1%) had pancytopaenia. Patients received a median of 50 mg/day (25-150 mg/day) of eltrombopagfor a median duration of 82 (24-386) days. Nine (23.1%) patients had autologous haematopoietic cell transplantation, and 30 (76.9%) had allogeneic haematopoietic cell transplantation (14 unrelated, 9 sibling and 7 haploidentical). The median donor age was 32 (20-67) years. The median follow-up was 16.4 (1.8-84.3) months. The median pre-treatment platelet count was 11x10/l (1-23), which increased to 41x10/l (6-150). The median platelet count increment was 29.5x10/l ( = 0.001). The pre-treatment median neutrophil count was 1.19x10/l (0.39-5.1), which increased to 2.35 x10/l (0.1-5.33) ( = 0.05), and the pre-treatment median haemoglobin was 8.3 (6.2-14) g/dl, which increased to 10 (6.2-14) g/dl ( = 0.001) with eltrombopag. No eltrombopag-related hepatotoxicity occurred; however, 1 (2.6%) patient failed to continue treatment because of two consecutive episodes of deep venous thrombosis. Six (15.4%) patients were unresponsive to eltrombopag and dependent on blood product transfusions. After a median time of 82 days, 61.5% of the patients discontinued eltrombopag successfully.

Conclusion: The results confirmed that eltrombopag could provide a rapid, sustained response in patients with poor graft functioning after haematopoietic cell transplantation. This finding is essential given the high rate of non-relapse mortality caused by poor graft functioning after haematopoietic cell transplantation.