A Trial to Assess the Efficacy and Safety of Engasertib in Participants With Moderate to Severe Hereditary Hemorrhagic Telangiectasia (HHT)

September 16, 2026 updated by: Vaderis Therapeutics AG

A Phase 3, Randomized, Double-blind, Placebo-Controlled Study to Assess the Efficacy and Safety of Engasertib in Subjects With Moderate to Severe Hereditary Hemorrhagic Telangiectasia (HHT)

The primary objective of this trial is to assess the efficacy of engasertib 40 mg once daily (QD) in reducing the frequency of epistaxis compared to placebo QD during 28 weeks of double-blind treatment in participants with moderate to severe HHT.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

240

Phase

  • 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

  • Name: Vaderis Therapeutics AG
  • Phone Number: +1 844-823-3747
  • Email: info@vaderis.com

Study Locations

  • United States
    • Illinois
      • Chicago, Illinois, United States, 60637
        • Recruiting
        • The University of Chicago Medical Center (UCMC)
        • Contact:
    • Indiana
      • Indianapolis, Indiana, United States, 46260
        • Recruiting
        • Innovative Hematology, Inc.,
        • Contact:
    • Minnesota
      • Rochester, Minnesota, United States, 55905
        • Recruiting
        • Mayo Clinic
        • Contact:
    • Missouri
      • St Louis, Missouri, United States, 63110
        • Recruiting
        • Washington University School of Medicine
        • 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

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  1. Participants are ≥18 years of age at the Screening Visit.

  2. Participants have a definite diagnosis of HHT by the Curaçao criteria, defined as spontaneous and recurrent epistaxis and having at least 2 of the following criteria:

    1. Multiple telangiectases at characteristic sites: lips, oral cavity, fingers, or nose;
    2. Visceral lesions: gastrointestinal telangiectasia and/or pulmonary, hepatic, cerebral, or spinal arteriovenous malformations (AVMs); or
    3. A first degree relative with HHT according to these criteria.
  3. Participants must have an ESS >4 at screening, and, in the judgement of the Investigator, participants are expected to have regular epistaxis that typically lasts for several minutes. This criterion is assessed at screening only and does not require reconfirmation prior to randomization on Day 1.
  4. Participants have anemia OR in the prior 6 months have received a parenteral infusion of at least 250 mg of iron OR in the prior 6 months have received a red cell or whole blood transfusion.

Exclusion Criteria:

  1. History or current diagnosis of clinically significant electrocardiogram (ECG) abnormalities.
  2. History of significant or uncontrolled skin disorders per Investigator's judgement.
  3. Local ablative (eg, cauterization) or surgical procedures on nasal telangiectases <6 weeks before the Screening Visit.
  4. Use of drugs with anti-angiogenic properties, including, but not limited to, bevacizumab, pazopanib, thalidomide, lenalidomide, pomalidomide, tacrolimus, sirolimus, or selective estrogen response modulators (tamoxifen, raloxifene, or bazedoxifene) < 6 weeks before the Screening Visit.
  5. Use of oral tranexamic or epsilon-aminocaproic acid unless they are on a stable dose for at least 4 weeks before the Screening Visit, which will need to be continued during the entire duration of the double-blind Treatment Period.

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: Double

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Engasertib 40 mg
Participants will receive engasertib as an oral capsule QD for 28 weeks.
Drug: Engasertib
Engasertib will be administered as oral capsules.
Other Names:
  • VAD044
Placebo Comparator: Placebo
Participants will receive matching placebo as an oral capsule QD for 28 weeks.
Drug: Placebo
Placebo will be administered as oral capsules.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Total Number of Epistaxis Events Through Week 28
Time Frame: Day 1 through Week 28
Day 1 through Week 28

Secondary Outcome Measures

Outcome Measure
Time Frame
Absolute Change from Baseline in Total Duration of Epistaxis at Week 28
Time Frame: Baseline and Week 28
Baseline and Week 28
Absolute Change from Baseline in Epistaxis Severity Score (ESS) at Week 28
Time Frame: Baseline and Week 28
Baseline and Week 28
Absolute Change from Baseline in the Nasal Outcome Score for Epistaxis in HHT (NOSE HHT) Score at Week 28
Time Frame: Baseline and Week 28
Baseline and Week 28
Absolute Change in Red Blood Cell (RBC) Unit Equivalents (RUEs) Received at Week 28
Time Frame: Baseline and Week 28
Baseline and Week 28
Patient Global Impression of Change (PGIC) Nosebleeds Sub-score at Week 28
Time Frame: Week 28
Week 28
HHT-specific Quality of Life (HHT-QoL) Score at Week 28
Time Frame: Week 28
Week 28
Absolute Change from Baseline in the Intensity-adjusted Duration of Epistaxis per Month at Week 28
Time Frame: Baseline and Week 28
Baseline and Week 28

Collaborators and Investigators

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

Sponsor

Vaderis Therapeutics AG

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)

September 1, 2026

Primary Completion (Estimated)

June 1, 2028

Study Completion (Estimated)

June 1, 2028

Study Registration Dates

First Submitted

July 29, 2026

First Submitted That Met QC Criteria

July 29, 2026

First Posted (Actual)

August 4, 2026

Study Record Updates

Last Update Posted (Actual)

September 17, 2026

Last Update Submitted That Met QC Criteria

September 16, 2026

Last Verified

September 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • HHT-301
  • 2025 (U.S. NIH Grant/Contract: Faculty of Social Sciences Scientific Grant at the University of Gdańsk)
  • 2025-524490-17-00 (Ctis)

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

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.

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