Clinical Efficacy of Avatrombopag in the Treatment of Patients with Post-Transplantation Thrombocytopenia

Post-transplantation thrombocytopenia (PT) is a common, serious complication following allogeneic hematopoietic stem cell transplantation (allo-HSCT) and can lead to increased transplantation-related mortality. The current treatment regimen for PT based on immune thrombocytopenia (ITP) has a limited effectiveness. Avatrombopag, a second-generation oral, small-molecule thrombopoietin receptor agonist (TPO-RA), has shown favourable therapeutic effect in ITP, chemotherapy-induced thrombocytopenia and thrombocytopenia associated with chronic liver disease, and may be an alternative choice for patients sufferring from PT. The clinical data of 34 cases with PT treated with avatrombopag at the Union Hospital of Huazhong University of Science and Technology from June 2021 to April 2023 were retrospectively analysed to investigate the efficacy and safety of the treatment.The study endpoints were overall response rate (ORR) of avatrombopag response and adverse drug reactions at week 8 of the treatment phase. platelet count level above 50×10⁹/L for 7 consecutive days without the need for platelet transfusions was considered as avatrombopag response. In this study, 34 cases with PT were included, of which 85.3% (N = 29) were secondary failure of platelet recovery (SFPR), 14.7% (N = 4) were delayed platelet engraftment (DPE). Avatrombopag was administred at a median time of 75.5 days post-transplantation. The overall response rate was 79.4% (N = 27), which was slightly higher in the SFPR group than that in the EPD group (82.8% vs 60.0%, P = 0.268). We observed 3 patients who were still effective after a second administration of avatrombopag. The mild reversible hepatic dysfunction (11.8%, N = 4) and thrombosis (2.9%, N = 1) were documented adverse events in the study period. Additionally, some cases have developed pulmonary infections (11.8%, N = 4), hemorrhagic cystitis (2.9%, N = 1) cytomegalovirus viremia (2.9%, N = 1), limited chronic graft versus-host disease (11.8%, N = 4) during avatrombopag treatment. Consequently, avatrombopag might offer a treatment option for patients with thrombocytopenia following allo-HSCT, which was effective and safe.

No relevant conflicts of interest to declare.