Background and Importance Poor graft function is a rare and serious complication in patients who have undergone haematopoietic stem cell transplantation (HSCT).

It is characterised by moderate to severe cytopenias (haemoglobin less than 10 g/dl, platelets less than 20* 10^9/L, neutrophils less than 1 * 10^9/L) requiring transfusion support or G-CSF, in patients with complete chimerism.

Currently, treatment options are very limited and not without complications.

Aim and Objectives Our aim is to evaluate the effectiveness of eltrombopag as an off-label indication in patients with poor graft function who have undergone HSCT.

Material and Methods Observational, retrospective, longitudinal study in which the effectiveness and safety of eltrombopag was evaluated in patients with poor graft function who received HSCT between January 2018 to January 2023. Patients were analysed from the start of eltrombopag until recovery of function and/or death.

Poor graft function was defined as the presence of sustained thrombopenia (<20 x10^9/L) despite transfusion support.

Effectiveness was assessed by the overall haematological response rate: platelet recovery (platelets >50 x10^9/L for >4 weeks).

Data analysis was performed using SPSS 21.0 statistical software. Variables were analysed using descriptive statistics.

Results 37 patients (56.8% male), mean age 50.9 years (SD= 13.03) were analysed. The most prevalent diagnosis was acute myeloid leukaemia (43.2%), followed by myelodysplastic syndrome (13.5%) and non-Hodgkin’s lymphoma (10.8%). The most frequent type of transplant was haploidentical (78.4%).

The median start of treatment since HSCT was 76 days. Most patients started with an eltrombopag dose of 50 mg (56.8%).

The mean platelet count before the start of treatment was 25.378/µL, while at the end of treatment the mean platelet count was 73.162/µL.

Platelet recovery was achieved in 59.5% of patients. The median duration of treatment was 4.1 months.

Conclusion and Relevance Among the few existing therapeutic alternatives for thrombopenia resulting from poor graft function, the use of eltrombopag shows response rates close to 60%, so it appears to be an effective alternative.

Conflict of Interest No conflict of interest.