Adding eltrombopag to intensive immunosuppressive therapy for severe aplastic anaemia may help adult patients achieve outcomes similar to paediatric patients

Abstract

Aplastic anaemia (AA) is a disorder in which the bone marrow fails to produce enough blood cells [1]. For patients with severe aplastic anaemia (SAA) who are ineligible for haematopoietic stem cell transplantation (HSCT), intensive immunosuppressive therapy (IST) with antithymocyte globulin (ATG) and cyclosporin A (CsA) is recommended [2]. However, the efficacy of IST alone is higher in children than in adults. Recently, eltrombopag (EPAG) has been proven to enhance the haematologic response to AA treatment [3, 4]. Whether the difference between adults and children still exists during treatment with IST + EPAG remains unclear. To date, no direct comparison of adults and children has been conducted. The aim of this study was to evaluate the differences in treatment efficacy and survival between adults and children treated with different regimens.

The haematologic response was evaluated in each patient. Among the patients receiving IST alone, the complete response rate (CRR) of adults was lower than that of children at 12 months (31% vs. 48%, P = 0.048), but there was no difference in the overall response rate (ORR) between adults and children at 3, 6, or 12 months (52% vs. 59%, P = 0.426; 69% vs. 74%, P = 0.599; 76% vs. 75%, P = 1.000, respectively). Relatedly, there was no difference in the CRR at 3 and 6 months between the adults and children (3% vs. 11%, P = 0.113; 21% vs. 22%, P = 0.849, respectively). The time to response was 4.3 (IQR 2.9–6.3) months in adults and 3.2 (IQR 2.5–4.0) months in children (P = 0.243), and the time to CR was 8.5 (IQR 6.8–11.0) months in adults and 7.5 (IQR 6.0–10.5) months in children (P = 0.113). Among the patients with IST + EPAG, there was no difference in the ORR between adults and children at 3 or 6 months (67% vs. 64%, P = 0.868; 83% vs. 76%, P = 0.567, respectively), but adults had a higher ORR at 12 months (89% vs. 73%, P = 0.027). There was also no difference in the CRR at 3, 6 and 12 months between the two groups (13% vs. 21%, P = 0.229; 25% vs. 38%, P = 0.124; 54% vs. 50%, P = 0.614, respectively; Fig. 1). The time to response was 3.0 (IQR 2.8–3.3) months in adults and 2.5 (IQR 1.9–3.9) months in children (P = 0.361). Moreover, the time to CR was 6.0 (IQR 3.0–8.3) months for adults and 3.9 (IQR 2.5–5.7) months for children (P = 0.478).