Evaluation of Avatrombopag for the Treatment of Thrombocytopenia in Japanese Adults With Chronic ITP

NCT ID: NCT05369208

Last Updated: 2026-01-15

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: PHASE3
• Total Enrollment: 19 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2022-06-15
• Study Completion Date: 2025-10-29

Brief Summary

Evaluate the efficacy, safety, and PK of avatrombopag given for 26 weeks in Japanese adults with chronic immune thrombocytopenia (ITP).

Detailed Description

This Phase 3, multicenter, open label study will evaluate the efficacy, safety, and population pharmacokinetics (PK) of avatrombopag in Japanese adults with chronic ITP. At least 19 subjects will be enrolled. The study will consist of 3 phases: Pre-enrollment, Primary Investigation, and Extension Phase until market authorization in Japan.

Conditions

Immune Thrombocytopenia

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

Avatrombopag

Avatrombopag 20 mg oral tablet

Group Type: OTHER

Avatrombopag Oral Tablet

Intervention Type: DRUG

Avatrombopag 20 mg given once daily (initial dose). Dosage adjustments were determined by the physician to maintain a platelet count between 50 x 10\^9 to 200 x 10\^9 as defined in the protocol and in accordance with overseas labeling.

Interventions

Avatrombopag Oral Tablet

Avatrombopag 20 mg given once daily (initial dose). Dosage adjustments were determined by the physician to maintain a platelet count between 50 x 10\^9 to 200 x 10\^9 as defined in the protocol and in accordance with overseas labeling.

Intervention Type: DRUG

Other Intervention Names

Doptelet

Eligibility Criteria

Inclusion Criteria

• Subject has a confirmed diagnosis of chronic immune thrombocytopenia (ITP) (≥12 months duration) and has had an insufficient response to a previous ITP treatment, in the opinion of the Investigator.
• Subject has an average of 2 platelet counts <30×10^9/L (no single count can be >35×10^9/L). The 2 samples must be obtained ≥48 hours and ≤2 weeks apart.

Exclusion Criteria

• Subjects with known secondary immune thrombocytopenia (e.g., with known Helicobacter pylori-induced ITP, subjects infected with known human immunodeficiency virus (HIV) or hepatitis C virus (HCV) or subjects with known systemic lupus erythematosus).
• Subjects with known inherited thrombocytopenia (e.g., Myosin Heavy Chain 9 (MYH-9) disorders) or hereditary thrombophilic disorders (e.g., Factor V Leiden, antithrombin III deficiency).
• History of myelodysplastic syndrome (MDS).
• History of arterial or venous thrombosis.
• Subjects with a history of significant cardiovascular disease (e.g., congestive heart failure (CHF) New York Heart Association Grade III/IV, arrhythmia known to increase the risk of thromboembolic events [e.g., atrial fibrillation], angina, coronary artery stent placement, angioplasty, coronary artery bypass grafting).
• Subjects with a history of cirrhosis, portal hypertension, or chronic active hepatitis.
• Subjects with concurrent malignant disease or receiving cytotoxic chemotherapy for a reason other than ITP treatment.
• Use of immunoglobulins (IVIg and anti-D) or corticosteroid rescue therapy within 1 week of Day 1/Baseline.
• Splenectomy or use of rituximab within 12 weeks of Day 1/Baseline.
• Use of romiplostim or eltrombopag within 1 week of Day 1/Baseline.
• Use of chronic corticosteroid treatment or azathioprine within 4 weeks of Day 1/Baseline, unless receiving a stable dose for at least 4 weeks.
• Use of mycophenolate mofetil, cyclosporin A, or danazol within 4 weeks of Day 1/Baseline, unless receiving a stable dose for at least 12 weeks.
• Use of cyclophosphamide or vinca alkaloid regimens within 4 weeks of Baseline Visit.
• Currently receiving moderate or strong dual inhibitors/inducers of CYP2C9 and CYP3A4.
• Serum creatinine ≥1.5× the upper limit of normal (ULN).
• Serum bilirubin ≥2×ULN.
• Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) ≥3×ULN.
• Females who are pregnant (positive beta-human chorionic gonadotropin (β-hCG) test) or breastfeeding.
• Received treatment with an investigational drug within 30 days or 5 half-lives (whichever is longer) before Day 1/Baseline.

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Sobi, Inc.

INDUSTRY

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Locations

Sobi Site 105

Toyohashi, Aichi-ken, Japan

Sobi Site 110

Tōon, Ehime, Japan

Sobi Site 118

Iizuka-shi, Fukuoka, Japan

Sobi Site 116

Kitakyushu, Fukuoka, Japan

Sobi Site 117

Kurume, Fukuoka, Japan

Sobi Site 114

Gifu, Gifu, Japan

Sobi Site 115

Fukuyama-shi, Hiroshima, Japan

Sobi Site 109

Hiroshima, Hiroshima, Japan

Sobi Site 108

Kobe, Hyōgo, Japan

Sobi Site 113

Kanazawa, Ishikawa-ken, Japan

Sobi Site 101

Shiwa-gun, Iwata, Japan

Sobi Site 111

Fujisawa, Kanagawa, Japan

Sobi Site 119

Kumamoto, Kumamoto, Japan

Sobi Site 107

Hirakata, Osaka, Japan

Sobi Site 106

Suita, Osaka, Japan

Sobi Site 104

Hachiōji-shi, Tokyo, Japan

Sobi Site 103

Bunkyō City, Toyko, Japan

Sobi Site 102

Chuo-shi, Yamanashi, Japan

Sobi Site 112

Kofu, Yamanashi, Japan

Countries

Japan

Provided Documents

Document Type: Study Protocol

View Document

Document Type: Statistical Analysis Plan

View Document

Other Identifiers

AVA-ITP-307

Identifier Type: -

Identifier Source: org_study_id