Romiplostim for Oral TPO-RA Resistant ITP

Summary

This study is a prospective, multicenter, open-label, single-arm cohort study to evaluate the effectiveness and safety of romiplostim in patients with immune thrombocytopenia (ITP) who have not responded to oral thrombopoietin receptor agonists (TPO-RAs) such as eltrombopag, hetrombopag, or avatrombopag.

ITP is a blood disorder in which the immune system attacks and destroys the body's own platelets, leading to low platelet counts and an increased risk of bleeding. While oral TPO-RAs are effective for many patients, approximately 20-30% of patients do not respond adequately or lose response over time. For these patients, alternative treatments are urgently needed.

Participants in this study will discontinue their current oral TPO-RA and receive romiplostim as a weekly subcutaneous injection. The starting dose is 3 µg/kg, and the dose may be adjusted weekly based on platelet counts (maximum 10 µg/kg). The total treatment and follow-up period is 24 weeks.

The primary outcome measure is the durable platelet response rate at week 24, defined as maintaining platelet counts at ≥50×10⁹/L for at least two scheduled visits during weeks 22-24 without rescue therapy. Secondary outcomes include the sustained response rate at week 12, complete response rate at week 24, time to first response, improvement in bleeding events, and quality of life assessment.

Safety outcomes include monitoring for thromboembolic events, bone marrow fibrosis, hepatotoxicity, injection site reactions, and other adverse events according to CTCAE v5.0.

Approximately 60 participants will be enrolled across multiple centers in China. This study aims to provide evidence for romiplostim as a treatment option for ITP patients who have failed oral TPO-RAs.

Conditions

• Immune (Idiopathic) Thrombocytopenic Purpura (ITP)

Interventions

DRUG

Romiplostim

Romiplostim is administered as a subcutaneous injection once weekly for 24 weeks. The starting dose is 3 µg/kg. Platelet count is assessed weekly, and the dose is adjusted based on platelet count and bleeding symptoms as follows: If platelet count \<50×10⁹/L: increase dose by 1 µg/kg (maximum dose: 10 µg/kg per week) If platelet count 50-200×10⁹/L: maintain the lowest dose that reduces bleeding risk If platelet count 200-400×10⁹/L: decrease dose by 1 µg/kg If platelet count \>400×10⁹/L: withhold dosing. After platelet count decreases to \<200×10⁹/L, resume at a dose 1 µg/kg lower than the dose before withholding.

Sponsors & Collaborators

• Affiliated Hospital of Nantong University

  collaborator OTHER

• Changshu Affiliated Hospital of Soochow University

  collaborator OTHER

• The First People's Hospital of Changzhou

  collaborator OTHER

• Shanghai Tong Ren Hospital

  collaborator OTHER

• The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School

  collaborator OTHER

• Zhangjiagang First People's Hospital

  collaborator OTHER

• Soochow Hopes Hematonosis Hospital

  collaborator UNKNOWN

• The First Affiliated Hospital of Soochow University

  lead OTHER

Study Design

Allocation

NA

Purpose

TREATMENT

Masking

NONE

Model

SINGLE_GROUP

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2026-03-15

Primary Completion

2027-09-30

Completion

2028-06-30

Countries

• China

Study Locations