The Safety, Tolerability, Pharmacokinetics, and Preliminary Efficacy of HMPL-523 in Adult Subjects With Immune Thrombocytopenia (ITP)

September 10, 2025 updated by: Hutchmed

A Multicenter, Phase 1b Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Preliminary Efficacy of HMPL-523, a Syk Inhibitor, in Adult Subjects With Immune Thrombocytopenia

This is an open-label, multicenter study to evaluate the safety, tolerability, and efficacy of HMPL-523 in adult subjects with ITP.

Study Overview

Status

Withdrawn

Conditions

Intervention / Treatment

Detailed Description

This study is a Phase 1b, open-label, multicenter, single-arm study to evaluate the safety, tolerability, and preliminary efficacy of HMPL-523 in adult subjects with primary ITP diagnosed at least 3 months prior to enrollment or randomization.

In the dose escalation stage (Part 1), subjects will receive one of 3 dose levels of HMPL-523 to determine the recommended dose of HMPL-523 for the randomized dose optimization- stage (Part 2).

At the end of Part 1, 2 dose levels will be selected to be used in the dose-optimization stage (Part 2) of the study. In Part 2 of the study, subjects will be randomized in a 1:1 ratio between the 2 dose levels to better understand the exposure/efficacy/toxicity relationship.

At the end of Part 2, the Recommended Phase 3 dose (RP3D) of HMPL-523 will be determined based on the safety, efficacy and PK data.

Study Type

Interventional

Phase

  • Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Australia
      • Adelaide, Australia
        • Royal Adelaide Hospital
      • Canberra, Australia
        • Canberra Hospital
    • Victoria
      • Frankston, Victoria, Australia
        • Peninsula Private Hospital
    • Western Australia
      • West Perth, Western Australia, Australia
        • The Perth Blood Institute (PBI) Hollywood Specialist Centre
  • Germany
      • Berlin, Germany, 10117
        • Charité university
      • Düsseldorf, Germany, 40479
        • Marien Hospital Düsseldorf
      • Göttingen, Germany
        • UMG Gottingen Hämatologie
      • Lübeck, Germany
        • University Hospital of Schleswig-Holstein, Department of Haematology and Oncology
  • Norway
      • Grålum, Norway, 1714
        • Sykehuset Ostfold Kalnes (fosta) / Osfold Hospital Trust (MSL)
      • Oslo, Norway
        • Oslo University Hospital
  • Spain
      • Barcelona, Spain
        • Hospital Universitari Vall d'Hebron
      • Barcelona, Spain, 08003
        • Hospital del Mar Barcelona
      • Burgos, Spain, 09001
        • University de Burgos
      • Madrid, Spain, 28040
        • Fundacion Jimenez Diaz
      • Madrid, Spain, 28031
        • Hospital Infanta Leonor
      • Madrid, Spain, 28027
        • Clinica Universidad de Navarra
      • Madrid, Spain, 28007
        • Hospital Gregorio Marañón Madrid
      • Murcia, Spain, 30008
        • Hospital Morales Meseguer
  • United States
    • California
      • Irvine, California, United States, 92868
        • Childrens Hospital of California
    • Delaware
      • Georgetown, Delaware, United States, 20007
        • Georgetown University Medical Center - Georgetown Lombardi Comprehensive Cancer Center
    • Maryland
      • Bethesda, Maryland, United States, 20817
        • Center for Cancer and Blood Disorders
    • Massachusetts
      • Boston, Massachusetts, United States, 02114
        • Massachusetts General Hospital
    • New Mexico
      • Farmington, New Mexico, United States, 87401
        • San Juan Oncology Associates
    • North Carolina
      • Greenville, North Carolina, United States, 27834
        • East Carolina University, Brody School of Medicine
    • Ohio
      • Cleveland, Ohio, United States, 44106
        • Taussig Cancer Institute
    • Oklahoma
      • Tulsa, Oklahoma, United States, 74146
        • Oklahoma Cancer Specialists and Research Institute
    • Texas
      • San Antonio, Texas, United States, 78240
        • Texas Oncology San Antonio Medical Center
    • Washington
      • Seattle, Washington, United States, 98195
        • University of Washington (UW) Medical Center

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

Subjects may be enrolled in this study only if they satisfy all the following criteria:

  1. Adult male or female subjects ≥18 years of age
  2. Diagnosis of ITP, with a duration of disease of at least 3 months prior to randomization or enrollment
  3. Intolerance or insufficient response or recurrence after at least 1 prior ITP treatment (excluding splenectomy)
  4. Response (defined as achieved a platelet count ≥50 × 109/L) to at least 1 prior ITP therapy (including splenectomy)
  5. Adequate hematologic, hepatic and renal function

Exclusion Criteria:

Subjects are not eligible for enrollment into this study if any one of the following criteria are met:

  1. Evidence of the presence of secondary causes of ITP
  2. Clinically serious hemorrhage requiring immediate adjustment of platelets
  3. Known history of vital organ transplantation or hematopoietic stem-cell transplantation or chimeric antigen receptor T-cells (CAR-T) therapy
  4. Splenectomy within 12 weeks prior to enrollment
  5. Presence of active malignancy unless deemed cured by adequate treatment.
  6. History of serious cardiovascular disease corrected QT interval (QTcF) ≥450 ms
  7. Uncontrolled hypertension
  8. Being unsuitable to participate in this study as considered by investigators

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Non-Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Dose escalation
Part 1 will consist of the following 3 dose levels: 300, 400, and 500 mg once daily (QD).
Drug: HMPL-523
Syk inhibitor
Other Names:
  • sovleplenib
Experimental: Dose optimization stage
In part 2 subjects will be randomized in a 1:1 ratio between the 2 dose levels selected at the end of part 1.
Drug: HMPL-523
Syk inhibitor
Other Names:
  • sovleplenib

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Safety and tolerability of HMPL-523 in adult subjects with primary ITP
Time Frame: week 1 - week 24
Calculated as the number and percent incidence of participants experiencing adverse events (AE).
week 1 - week 24
Dose Limiting Toxicities
Time Frame: week 1 - week 4
Defined as an adverse event AE that meets protocol defined Dose Limiting Toxicities (DLT) criteria during the DLT assessment window (first 28 days), unless clearly unrelated to ITP drugs.
week 1 - week 4

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Cmax (maximum plasma drug concentration)
Time Frame: week 1 and week 3
Blood samples will be obtained from all patients to determine maximum plasma drug concentration of HMPL-523 and metabolite M
week 1 and week 3
AUCtau (area under the concentration-time curve over a dosage interval)
Time Frame: week 1 and week 3
Blood samples will be obtained from all patients to determine area under the concentration time curve over periodic dosing intervals for HMPL-523 and metabolite M1
week 1 and week 3
Tmax (time to reach maximum plasma drug concentration)
Time Frame: week 1 and week 3
Blood samples will be obtained from all patients to determine time to reach maximum plasma concentration of HMPL-523 and metabolite M1
week 1 and week 3
Cmin (minimum plasma drug concentration)
Time Frame: week 1 - week 20
Blood samples will be obtained from all patients to determine minimum plasma concentration of HMPL-523 and metabolite M1
week 1 - week 20

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Hutchmed

Investigators

  • Study Director: William Schelman, MD, PhD, Hutchmed

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

April 2, 2024

Primary Completion (Estimated)

April 1, 2026

Study Completion (Estimated)

November 1, 2026

Study Registration Dates

First Submitted

February 13, 2024

First Submitted That Met QC Criteria

February 29, 2024

First Posted (Actual)

March 4, 2024

Study Record Updates

Last Update Posted (Estimated)

September 16, 2025

Last Update Submitted That Met QC Criteria

September 10, 2025

Last Verified

September 1, 2025

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 2022-523-GLOB1

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Pathologic Processes

Clinical Trials on HMPL-523

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Guatemala

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe