Medical Information Only. Always consult your healthcare provider before enrolling in any clinical trial.
(HARBOR) Study to Evaluate Efficacy and Safety of BLU-263 Versus Placebo in Patients With Indolent Systemic Mastocytosis
NCT04910685 · View on ClinicalTrials.gov ↗
Study Summary
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.
Conditions Studied
Interventions
- DRUG Placebo
- DRUG Elenestinib
Study Locations (20)
Other
- Kepler Universitatsklinikum, Med Campus III. Clinic of Internal Medicine 3 - Hematology and Oncology — Linz
- CHU Amiens-Picardie — Amiens
- CHU de Caen — Caen
California
- David Geffen School of Medicine at UCLA — Los Angeles
- Stanford Cancer Institute — Palo Alto
New York
- Roswell Park Cancer Institute — Buffalo
- Columbia University Medical Center — New York
Alabama
- University of Alabama at Birmingham — Birmingham
Colorado
- UCHealth Blood Disorders and Cell Therapies Center - Anschutz Medical Campus — Aurora
Georgia
- Winship Cancer Institute, Emory University — Atlanta
Massachusetts
- Brigham and Women's Hospital — Boston
Michigan
- Michigan Medicine University of Michigan — Ann Arbor
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 534 participants |
| Start Date | 2021-11-30 |
| Est. Completion | 2032-09-30 |
| Phase | Phase 2 |
Interested in This Trial?
Always speak with your doctor before enrolling in a clinical trial.
Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT04910685
The ClinicalTrials.gov registry entry for NCT04910685 describes a study currently listed as recruiting. It is categorized as Phase 2, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 534 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is Blueprint Medicines Corporation, which has 9 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
The record links to 2 conditions, with Indolent Systemic Mastocytosis appearing as the primary indexed condition, and to 2 interventions — of which Placebo is the first listed. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT04910685 reports 20 study locations spanning 16 distinct geographic areas — top geographies include Other, California, New York. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
Frequently Asked Questions
What is clinical trial NCT04910685 about?
NCT04910685 is a clinical study titled "(HARBOR) Study to Evaluate Efficacy and Safety of BLU-263 Versus Placebo in Patients With Indolent Systemic Mastocytosis". 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 ...
What is the current status of trial NCT04910685?
This trial is currently recruiting. It is a Phase 2 study. The enrollment target is 534 participants. The study started on 2021-11-30. Estimated completion is 2032-09-30.
What conditions does trial NCT04910685 study?
This clinical trial studies the following conditions: Indolent Systemic Mastocytosis, Smoldering Systemic Mastocytosis. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT04910685?
The interventions under investigation include: Placebo (DRUG), Elenestinib (DRUG). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT04910685?
This trial is sponsored by Blueprint Medicines Corporation, which has 9 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
Where is trial NCT04910685 being conducted?
This trial has 20 study locations across Alabama, California, Colorado, Georgia, Massachusetts. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
Learn More About Clinical Trials
How Clinical Trials Work
Understand phases 1-4, trial design, randomization, and the informed consent process.
Patient Rights in Clinical Trials
Your rights as a participant: consent, withdrawal, privacy, and who to contact.
Finding the Right Clinical Trial
A practical guide to searching trials, understanding eligibility, and evaluating options.
All Guides
Browse our complete library of clinical trial educational resources.
Read our methodology — how this data is sourced, computed, and verified.