Usefulness of Repeated Lusutrombopag Administration in Clinical Practice and Its Correlation with the Simulation Software-Predicted Platelet Count: A Multicenter Study.

Objective Lusutrombopag is recommended for severe thrombocytopenia (<5.0×10⁴/μL) in patients with chronic liver disease who are scheduled to undergo invasive procedures. However, reports on the efficacy of repeated lusutrombopag dosing are scarce. It is also not known whether lusutrombopag causes the platelet count to exceed 5.0×10⁴/μL. We evaluated the efficacy of repeated lusutrombopag dosing and the efficacy of the platelet prediction simulation software program. Methods We evaluated the number of platelet elevations according to the number of lusutrombopag administrations. We also evaluated the correlation between the highest software-predicted platelet count and the platelet count measured in actual clinical practice. Patients This retrospective study included 236 patients treated with lusutrombopag at 11 medical institutions in Japan. Results The platelet count increased with the number of lusutrombopag administrations (1, 2, 3, 4, >4) in all groups, and no significant difference was found among the groups (p=0.169). In all groups, the platelet counts reached their highest levels at 8-14 days after treatment with lusutrombopag (p=0.243). There was a correlation between the highest software-predicted platelet count and the platelet count measured in actual clinical practice in all dose frequency groups; however, the correlation was the strongest in the one-dose group (r=0.74, p<0.0001). Conclusion Frequent lusutrombopag administration is therefore both effective and safe, and a platelet prediction simulation software program is thus considered to be useful in practice.