Low- vs High-Dose Sirolimus With Prednisolone for KHE and KMP

June 15, 2026 updated by: Yi Ji

Low-dose Versus High-dose Sirolimus Combined With Prednisolone for Kaposiform Hemangioendothelioma With Kasabach-Merritt Phenomenon: a Randomized Noninferiority Trial

This randomized clinical trial evaluates if low-dose sirolimus (target trough 4-8 ng/mL) combined with prednisolone is noninferior in efficacy but superior in safety compared to standard high-dose sirolimus (target trough 10-15 ng/mL) combined with prednisolone in pediatric patients with kaposiform hemangioendothelioma and Kasabach-Merritt phenomenon (KHE with KMP), with participants randomized 1:1 to receive the assigned regimen, undergo routine blood and imaging monitoring, and be evaluated for clinical response and adverse events.

Study Overview

Detailed Description

The goal of this randomized clinical trial is to evaluate if low-dose sirolimus combined with prednisolone is noninferior to high-dose sirolimus combined with prednisolone in managing kaposiform hemangioendothelioma complicated by Kasabach-Merritt phenomenon (KHE with KMP) in pediatric patients. In this study, the low-dose regimen targets a sirolimus trough concentration of 4-8 ng/mL, while the standard high-dose regimen targets a trough concentration of 10-15 ng/mL. The main questions it aims to answer are:

Does the combination of low-dose sirolimus (target trough 4-8 ng/mL) and prednisolone achieve a noninferior objective response rate (including platelet count recovery and tumor volume reduction) compared to the high-dose sirolimus (target trough 10-15 ng/mL) and prednisolone combination at the primary endpoint evaluation? Does the low-dose sirolimus combination significantly reduce treatment-related toxicities and adverse events compared to the high-dose sirolimus combination?

Researchers will compare a low-dose sirolimus plus prednisolone arm to a standard high-dose sirolimus plus prednisolone arm to see if lowering the sirolimus dose within this combination regimen can maintain comparable therapeutic control over KMP while minimizing dose-dependent adverse effects.

Participants will:

Be randomized in a 1:1 ratio to receive either oral low-dose sirolimus combined with prednisolone (targeting a trough level of 4-8 ng/mL) or standard high-dose sirolimus combined with prednisolone (targeting a trough level of 10-15 ng/mL).

Undergo regular clinical evaluations, including physical examinations and serial blood tests to monitor peripheral platelet counts and sirolimus trough levels.

Receive routine imaging studies (such as MRI or ultrasound) to assess changes in tumor volume.

Be closely monitored throughout the study period for combination therapy-related side effects and systemic corticosteroid-associated adverse events.

Study Type

Interventional

Enrollment (Estimated)

76

Phase

  • Phase 2
  • Phase 3

Contacts and Locations

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

Study Contact

Study Contact Backup

Study Locations

    • Sichuan
      • Chengdu, Sichuan, China, 610041
        • Recruiting
        • West China Hospital of Sichuan University
        • Sub-Investigator:
          • Jiangyuan Zhou, MD
        • Contact:
        • Contact:

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

  • Child
  • Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Presenting a KHE with the following characteristics:

    1. Clinical features and histological findings consistent with progressive, non-resectable KHE associated with KMP.
    2. Patients must be 0 - 18 years of age at the time of study entry.
    3. Without functional impairment requiring treatment of corticosteroid.
  • Organ function requirements:

    1 Adequate liver function:

    1. Total bilirubin less than or equal to 1.5 x upper limit of normal (ULN)for age, and
    2. ALT and AST less than or equal to 2.5 x upper limit normal (ULN) for age.

    2 Adequate renal function:

    1. 0-5 years of age maximum serum creatinine (mg/dL) of 0.8
    2. 6-10 years of age maximum serum creatinine (mg/dL) of 1.0
    3. 11-15 years of age maximum serum creatinine (mg/dL) of 1.2
    4. 16-18 years of age maximum serum creatinine (mg/dL) of 1.5
  • Adequate bone marrow function: Absolute Neutrophil Count (ANC) greater than or equal to 1 x 10 to the ninth/Liter.
  • Consent of parents (or the person having parental authority in families): Signed and dated written informed consent.

Exclusion Criteria:

  • Allergy to sirolimus or other rapamycin analogues.
  • Any known evidence of significant local or systemic uncontrolled infection, defined as receiving intravenous antibiotics at the time of randomization.
  • Patients must not be known to be Human Immunodeficiency Virus positive or known immunodeficiency. Testing is not required unless a condition is suspected.
  • Other concurrent severe and/or uncontrolled medical disease which could compromise participation in the study (e.g. uncontrolled diabetes, uncontrolled hypertension, severe malnutrition, chronic liver or renal disease, active upper gastrointestinal tract ulceration).
  • Impairment of gastrointestinal function or chronic gastrointestinal disease that may significantly alter the absorption of sirolimus.
  • Patients who have a history of malignancy.
  • Patients with an inability to participate or to follow the study treatment and assessment plan.

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: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Low-Dose Sirolimus Plus Prednisolone
Participants receive oral sirolimus with dose adjustments to maintain a target plasma trough concentration of 4-8 ng/mL, in combination with prednisolone, for a treatment duration of 12 months.
Participants will receive oral sirolimus in combination with prednisolone. Patients will be randomized in a 1:1 ratio to either a low-dose sirolimus group, with dose adjustments to maintain a target plasma trough concentration of 4-8 ng/mL, or a high-dose sirolimus group, with dose adjustments to maintain a target plasma trough concentration of 10-15 ng/mL. Prednisolone will be administered according to the study protocol and tapered based on clinical response. The total treatment duration will be 12 months.
Active Comparator: High-Dose Sirolimus Plus Prednisolone
Participants receive oral sirolimus with dose adjustments to maintain a target plasma trough concentration of 10-15 ng/mL, in combination with prednisolone, for a treatment duration of 12 months.
Participants will receive oral sirolimus in combination with prednisolone. Patients will be randomized in a 1:1 ratio to either a low-dose sirolimus group, with dose adjustments to maintain a target plasma trough concentration of 4-8 ng/mL, or a high-dose sirolimus group, with dose adjustments to maintain a target plasma trough concentration of 10-15 ng/mL. Prednisolone will be administered according to the study protocol and tapered based on clinical response. The total treatment duration will be 12 months.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Proportion of Participants Achieving Platelet Count Recovery
Time Frame: 2 months
The proportion of participants who achieve platelet count recovery, defined as a platelet count ≥100 × 10⁹/L without platelet transfusion support, during the study period.
2 months

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
The changes in the patient's symptoms and/or complications.
Time Frame: 6 and 12 months
Improvement in the range of motion.
6 and 12 months
Frequency of adverse events
Time Frame: 12 months
Frequency of adverse events (e.g. gastrointestinal disorders, blood and lymphatic system disorders, metabolic disorders or other abnormal laboratory results, skin disorders and general disorders, etc.) collected by investigator and reported by parents. All adverse events were collected and graded according to Common Terminology Criteria for Adverse Events, version 4.0 (CTCAE v4.0). The causality of the adverse event was determined by the multidisciplinary staff and was classified as definitively not related, probably not related, possibly related, probably related, or definitively related. Any dose reductions, interruptions, or cessations enacted at the discretion of the investigators were recorded.
12 months
Quality of life (QOL) in patients.
Time Frame: 12 months
Pediatric Quality of Life Inventory (PedsQLTM) 4.0 Genetic Core Infant Scales (<2 years) or Pediatric Quality of Life Inventory (PedsQLTM) 4.0 Genetic Core Scales (2-18 years) were used.
12 months
Proportion of Participants Achieving Fibrinogen Recovery
Time Frame: 2 months
The proportion of participants who achieve fibrinogen recovery, defined as a plasma fibrinogen level ≥1.6 g/L without replacement therapy, during the study period.
2 months
Change in D-Dimer Level From Baseline
Time Frame: 2 months
Change in plasma D-dimer level from baseline to the specified study assessment time point.
2 months
Change in KHE Tumor Volume From Baseline
Time Frame: 6 and 12 months
Response to therapy was measured by volumetric magnetic resonance imaging (MRI) analyses were performed at baseline and 6 and 12 months after treatment and were independently assessed by 2 radiologists. Changes in KHE size were classified as further growth (increase of ≥10%), no change (<10% increase and <10% decrease), partial involution (decrease of ≥10% and <75%), nearly complete involution (decrease of ≥75% and <100%), or complete involution (100%). Photographs of the mixed KHE were taken at months 0, 6 and 12 by a medical photographer.
6 and 12 months

Collaborators and Investigators

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

Sponsor

Investigators

  • Study Chair: Yi Ji, West China Hospital
  • Principal Investigator: Jiangyuan Zhou, MD, West China Hospital

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

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 (Estimated)

June 16, 2026

Primary Completion (Estimated)

December 31, 2027

Study Completion (Estimated)

December 31, 2028

Study Registration Dates

First Submitted

June 15, 2026

First Submitted That Met QC Criteria

June 15, 2026

First Posted (Actual)

June 18, 2026

Study Record Updates

Last Update Posted (Actual)

June 18, 2026

Last Update Submitted That Met QC Criteria

June 15, 2026

Last Verified

June 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

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.

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