(HARBOR) Study to Evaluate Efficacy and Safety of BLU-263 Versus Placebo in Patients With Indolent Systemic Mastocytosis
Public ClinicalTrials.gov record NCT04910685. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.
Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.
Official title
A Randomized, Double-Blind, Placebo-Controlled Phase 2/3 Study of BLU-263 in Indolent Systemic Mastocytosis
Brief summary
Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.
This is a randomized, double-blind, placebo-controlled, Phase 2/3 study comparing the efficacy and safety of elenestinib (BLU-263) + symptom directed therapy (SDT) with placebo + SDT in participants with indolent systemic mastocytosis (ISM) whose symptoms are not adequately controlled by SDT. Parts 1 and 2 will enroll participants with ISM. Participants enrolled in Part 2 will roll over onto Part 3 to receive treatment with elenestinib in an open-label fashion following completion of the earlier Part. Part K will enroll participants with ISM who have previously received an approved selective KIT inhibitor. The study also includes pharmacokinetic (PK) groups that will enroll participants with ISM.
Study identification
- NCT ID
- NCT04910685
- Recruitment status
- Recruiting
- Study type
- Interventional
- Phase
- Phase 2, Phase 3
- Enrollment
- 534 participants
Conditions and interventions
Eligibility (public fields only)
- Age range
- 18 Years and older
- Sex
- All
- Healthy volunteers
- Healthy volunteers not accepted
This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.
Study timeline
- Start date
- Nov 29, 2021
- Primary completion
- Sep 29, 2032
- Completion
- Sep 29, 2032
- Last update posted
- Aug 3, 2026
2021 – 2032
United States locations
- U.S. sites
- 14
- U.S. states
- 12
- U.S. cities
- 14
| Facility | City | State | ZIP | Site status |
|---|---|---|---|---|
| University of Alabama at Birmingham | Birmingham | Alabama | 35294 | Recruiting |
| David Geffen School of Medicine at UCLA | Los Angeles | California | 90095 | Recruiting |
| Stanford Cancer Institute | Palo Alto | California | 94305 | Recruiting |
| UCHealth Blood Disorders and Cell Therapies Center - Anschutz Medical Campus | Aurora | Colorado | 80045 | Recruiting |
| Winship Cancer Institute, Emory University | Atlanta | Georgia | 30322 | Recruiting |
| Brigham and Women's Hospital | Boston | Massachusetts | 02115 | Recruiting |
| Michigan Medicine University of Michigan | Ann Arbor | Michigan | 48109 | Recruiting |
| Mayo Clinic | Rochester | Minnesota | 55902 | Recruiting |
| Roswell Park Cancer Institute | Buffalo | New York | 14263 | Recruiting |
| Columbia University Medical Center | New York | New York | 10032 | Recruiting |
| Duke Asthma, Allergy and Airway Center | Durham | North Carolina | 27705 | Recruiting |
| University of Cincinnati Medical Center | Cincinnati | Ohio | 45219 | Recruiting |
| The University of Texas, MD Anderson Cancer Center | Houston | Texas | 77030 | Recruiting |
| Huntsman Cancer Institute, University of Utah | Salt Lake City | Utah | 84112 | Recruiting |
Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.
Non-U.S. locations
This page focuses on the U.S. directory. The official record also lists 61 non-U.S. sites.
About this trial record page
- What this page shows
- Public field values for ClinicalTrials.gov record NCT04910685, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
- What this page does not do
- No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
- Where the data comes from
- Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
- Last refresh
- Last update posted Aug 3, 2026 · Synced Sep 5, 2026
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Open the official record
The complete protocol, eligibility criteria, and contact information for NCT04910685 live on ClinicalTrials.gov.