Use of eltrombopag in treatment programs for patients with aplastic anemia

Introduction. The use of thrombopoietin receptor agonists, especially eltrombopag, in the treatment of aplastic anemia (AA) patients who did not respond to the previous immunosuppressive therapy (IST), is accompanied by the development of a hematological response in 40–60 % of patients.

Aim — to study the effi cacy of using eltrombopag in treatment programs for AA patients refractory to previous IST.

Methods. The study included 20  AA patients who were treated at the National Research Center for Hematology from 2015 to 2020. These patients did not respond to the conducted IST (ATG + CsA). Eltrombopag was administered at a dose of 150 mg/day. The results of treatment were assessed at 3 and 6 months: the achievement of hematological improvement, partial and complete remission, as well as the identifi cation of possible clonal evolution were determined.

Results. Eleven out of 20 (55 %) patients responded to treatment: 2 patients developed hematological improvement, 6 patients — partial remission, 3 patients — complete remission. All 11 patients responded to treatment within 12 months from the start of eltrombopag, but further positive dynamics of hematological parameters are possible. The median duration of treatment with eltrombopag was 11 (1–48) months. Most of the patients were treated with eltrombopag in combination with CsA. The duration of the course of treatment with eltrombopag depended on the response received (stable hematological improvement, remission, as well as the detection of clonal evolution) or its absence and the need for ATG or BMT. An aberrant karyotype was found in 2 AA patients who received eltrombopag: in one patient monosomy of chromosome 7 was detected 1 month after the start of treatment, in another patient, 37 months later, a clone with a derivative of chromosome 16 from t(1;16) and subclone with complex disorders of the karyotype without signs of myelodysplasia in the bone marrow.

Conclusion. The inclusion of the TPO receptor agonist eltrombopag in the treatment program for AA patients allows for a stable hematological response and remission of AA for patients who have not responded to IST. The effectiveness of eltrombopag is determined by adherence to the treatment algorithm, the optimal duration of the course, and the dose of the drug used. There is still a need for long-term observation of the patient and control morphological and cytogenetic studies.

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