03:00 PM Abstract No. 73 Efficacy of Avatrombopag (AVA) in optimizing platelet counts (PC) in chronic liver disease (CLD) patients with thrombocytopenia (TCP) undergoing interventional radiology (IR) procedures

Abstract

Patients with CLD often have severe TCP (<50×109/L) that can complicate the multiple invasive procedures these patients require, due to the increased bleeding risk. Society of IR clinical practice guidelines recommend a PC >=50×109/L prior to conducting many procedures in these patients. Avatrombopag (AVA) is a thrombopoietin receptor agonist currently available as an alternative to platelet transfusions for the prophylactic treatment of patients with TCP and CLD undergoing a procedure. Subgroup analyses of Phase 3 data evaluating the use of AVA in CLD patients undergoing IR procedures are summarized. Two randomized, double-blind, placebo (PBO)-controlled Phase 3 trials enrolled adults with CLD and PC <50×109/L undergoing a procedure (N=435). Patients were randomized 2:1 to AVA or PBO and dosed orally for 5 days based on Baseline PC. Those with a Baseline PC <40×109/L (Low Baseline Cohort) received 60 mg AVA, and those with PC 40 to <50×109/L (High Baseline Cohort) received 40 mg AVA; Procedure Day was scheduled within 5 to 8 days after the last dose. In these subgroup analyses, IR procedures were identified (n=121) and efficacy endpoints evaluated. The primary efficacy endpoint was the proportion of patients not requiring a platelet transfusion or rescue procedure for bleeding up to 7 days post-procedure. Secondary endpoints included patients achieving a PC of >=50×109, and the mean PC change from Baseline. In IR procedures, AVA demonstrated superiority over placebo in reducing the number of patients requiring a platelet transfusion or rescue procedure for bleeding (High Baseline Cohort: AVA 88.2%, PBO 38.9%; Low Baseline Cohort: AVA 61.9%, PBO 11.1%). Treatment with AVA also led to a higher proportion of patients achieving a PC >=50×109 (High Baseline Cohort: AVA 94.1%, PBO 44.4%; Low Baseline Cohort: AVA 69.1%, PBO 3.7%). In addition, AVA led to an approximate doubling of the mean Baseline PC. The adverse event profile was similar to that of placebo. AVA was superior to placebo in increasing PC to >=50×109/L and reducing platelet transfusions in patients undergoing IR-related procedures with a safety profile similar to that of placebo.