A retrospective study on the efficacy and safety of avatrombopag in the treatment of chemotherapy-induced thrombocytopenia in gastrointestinal cancer.

Abstract

e16334 Background: Chemotherapy-induced thrombocytopenia (CIT) is defined as post-chemotherapy platelets count < 100×109/L. Avatrombopag is an oral thrombopoietin receptor to treat thrombocytopenia. Although many factors lead to an increased risk of CIT in gastrointestinal cancer, there is currently no targeted research. This study aimed to investigate the efficacy and safety of avatrombopag for CIT in gastrointestinal cancer. Methods: This multicenter, retrospective study included adult gastrointestinal cancer patients with CIT who received avatrombopag treatment (40mg/60mg, 5 days) between September 2020 and February 2022. The patient meets one of the following conditions were included in this study: a) Platelet count <100×109/L before receiving avatrombopag treatment in the current chemotherapy cycle, and platelet count <50×109/L in the last cycle; b) Platelet count <75×109/L before receiving avatrombopag treatment in the current chemotherapy cycle. The main endpoint was the proportion of patients with platelet count >100×109/L or platelet count increased by >50×109/L or platelet count increased by > 100% in the cycle after the start of avatrombopag therapy. Results: 58 patients were included in this study. 53.40%, 82.80%, and 96.6% of the patients reached the effective endpoint after 5±2, 11±3, and 18±3 days of avatrombopag treatment, respectively. No drug toxicity related to avatrombopag was found in this study. No significant influencing factors of effective rate were found. And there was no significant difference was found among the effective rate and platelet transfusion rate of avatrombopag (AVA), AVA+Recombinant Human Interleukin-11 (rhIL-11), and AVA+Recombinant Human Thrombopoietin (rhTPO). However, compared with AVA+IL-11, the AVA+rhTPO group had lower baseline platelet counts. And the mean of increasing platelet counts on the 5±2 (41.32×109/L vs. 37.00×109/L) and 11±3 day (110.94×109/L vs. 84.00×109/L) were better in the AVA+rhTPO group, though not significantly. Conclusions: Avatrombopag has high efficacy and safety in the treatment of CIT in gastrointestinal cancer. rhTPO rather than rhIL-11 combined with avatrombopag may be more suitable for patients with low baseline platelet counts. [Table: see text]