Avatrombopag for Severe Thrombocytopenia After Liver Transplantation: A Retrospective Cohort Study

Effectiveness and Safety of Avatrombopag for Severe Post-Transplantation Thrombocytopenia in Liver Transplant Recipients: A Propensity-Score Matched Retrospective Cohort Study

Severe post-transplantation thrombocytopenia (platelet count <30×10⁹/L) occurs frequently after liver transplantation (LT) and is associated with increased bleeding risk, allograft dysfunction, and transfusion-related complications. Avatrombopag, an oral thrombopoietin receptor agonist, is approved for thrombocytopenia in chronic liver disease but its role in the post-LT setting remains unclear. This retrospective cohort study included adult LT recipients who developed severe post-transplantation thrombocytopenia (SPT) between November 2019 and August 2025. After 1:1 propensity score matching (nearest neighbor, caliper = 0.2 SD of the logit of the propensity score) for age, sex, etiology of liver disease, cold ischemia time (CIT), intraoperative blood loss (IBL), preoperative platelet count, and Model for End-stage Liver Disease (MELD) score, 67 patients who received avatrombopag (20 mg/day for 5 days) were compared with 67 matched controls who received standard care. The primary outcome was platelet rise rate (×10⁹/L/day). Secondary outcomes included absolute platelet increase, blood product utilization, concomitant thrombopoietic agent use, and 30-day complications (thrombosis, infection, mechanical ventilation, renal replacement therapy, death).

Study Overview

• Status: Completed
• Conditions: Postoperative Complication; Severe Thrombocytopenia; Liver Transplanatation
• Intervention / Treatment: Drug: Avatrombopag 20 mg Oral Tablet

• Study Type: Observational
• Enrollment (Actual): 134

Contacts and Locations

Study Locations

• China
  • Shanghai Municipality
    • Shanghai, Shanghai Municipality, China, 200032
      • Zhongshan Hospital, Fudan University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Adult patients who underwent liver transplantation at Zhongshan Hospital, Fudan University between November 2019 and August 2025

Description

Inclusion Criteria: (1) were aged 18 years or older; and (2) developed severe post transplantation thrombocytopenia (SPT), defined as a nadir platelet count below 30×10⁹/L within the first 7 days after LT.

Exclusion criteria: (1) use of avatrombopag within 4 weeks before LT; (2) second or subsequent LT; (3) death from surgical complications within 7 days after LT; (4) incomplete platelet measurement records; and (5) age younger than 18 years.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Arm 1: Avatrombopag Group / Arm 2: Control Group; Arm 1: Avatrombopag Group. Standard postoperative care with 20 mg orally once daily for 5 days, initiated when postoperative platelet count fell below 30×10⁹/L. Arm 2: Control Group. Standard postoperative care without avatrombopag	Drug: Avatrombopag 20 mg Oral Tablet; 20 mg orally once daily for 5 days, initiated when postoperative platelet count fell below 30×10⁹/L after liver transplatation

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
platelet rise rate	The platelet rise rate was calculated as (postoperative peak platelet count - postoperative nadir platelet count) divided by (time to peak - time to nadir + 1), measured in ×10⁹/L/day.	30 days post-LT

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Absolute platelet increase (×10⁹ cells/L)	Postoperative peak minus postoperative nadir.	30 days post-Liver transplatation
Red blood cell transfusion volume (units)	Units of packed red blood cells transfused within 30 days after LT.	30 days post-Liver transplatation
Platelet transfusion volume (bags)	Bags of platelets transfused within 30 days after LT.	30 days post-Liver transplatation
Concomitant thrombopoietic agent use	Use of other thrombopoietic agents (e.g., recombinant human thrombopoietin), recorded as binary (yes/no).	30 days post-Liver transplatation
Infection (culture-proven + symptoms)	Presence of culture-confirmed infection with accompanying clinical symptoms within 30 days after LT.	30 days post-Liver transplatation
Mechanical ventilation requirement	Requirement for postoperative mechanical ventilation support.	30 days post-Liver transplatation
Renal replacement therapy requirement	Requirement for postoperative dialysis.	30 days post-Liver transplatation
Thrombotic events	Deep vein thrombosis or hepatic artery thrombosis.	30 days post-Liver transplatation
30-day mortality	All-cause death within 30 days after liver transplantation.	30 days post-Liver transplatation

Collaborators and Investigators

• Sponsor: Shanghai Zhongshan Hospital

Study record dates

Study Major Dates

• Study Start (Actual): November 1, 2019
• Primary Completion (Actual): August 31, 2025
• Study Completion (Actual): August 31, 2025

Study Registration Dates

• First Submitted: May 16, 2026
• First Submitted That Met QC Criteria: May 16, 2026
• First Posted (Actual): May 22, 2026

Study Record Updates

• Last Update Posted (Actual): May 22, 2026
• Last Update Submitted That Met QC Criteria: May 16, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Avatrombopag; Platelet recovery; Liver transplanatation; Severe Thrombocytopenia
• Additional Relevant MeSH Terms: Cytopenia; Pathologic Processes; Hematologic Diseases; Blood Platelet Disorders; Pathological Conditions, Signs and Symptoms; Hemic and Lymphatic Diseases; Thrombocytopenia; Postoperative Complications; Pharmaceutical Preparations; Dosage Forms; Tablets; avatrombopag
• Other Study ID Numbers: B2026-303

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO