Actively Recruiting

Phase 2
Phase 3
Age: 18Years +
All Genders
NCT04910685

(HARBOR) Study to Evaluate Efficacy and Safety of BLU-263 Versus Placebo in Patients With Indolent Systemic Mastocytosis

Led by Blueprint Medicines Corporation · Updated on 2026-04-20

534

Participants Needed

64

Research Sites

565 weeks

Total Duration

On this page

AI-Summary

What this Trial Is About

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

Official Title

(HARBOR) Study to Evaluate Efficacy and Safety of BLU-263 Versus Placebo in Patients With Indolent Systemic Mastocytosis

Who Can Participate

Age: 18Years +
All Genders

Eligibility Criteria

Eligible

You may qualify if you...

  • Participant must have an Eastern Cooperative Oncology Group Performance Status (ECOG PS) of 0 to 2.
  • Participant has confirmed diagnosis of indolent systemic mastocytosis (ISM) confirmed by Central Pathology Review (for Parts 1, 2, K, and PK groups).
  • Participant has confirmed diagnosis of smoldering systemic mastocytosis (SSM) confirmed by central pathology review of bone marrow biopsy and WHO diagnostic criteria (for Part S).
  • Participant's symptoms are not adequately controlled by at least two symptom-directed therapies, including H1 blockers, H2 blockers, proton-pump inhibitors, leukotriene inhibitors, cromolyn sodium, corticosteroids, or omalizumab (for Parts 1 and PK groups).
  • Symptom-directed therapy (SDT) for ISM symptom management must be stable for at least 14 days before starting screening.
  • For participants on corticosteroids, the dose must be 20 mg/day prednisone or equivalent or less and stable for at least 14 days.
Not Eligible

You will not qualify if you...

  • Participants diagnosed with cutaneous mastocytosis only, SM with associated hematologic neoplasm of non-mast cell lineage, aggressive systemic mastocytosis, mast cell leukemia, or mast cell sarcoma.
  • Participants diagnosed with another myeloproliferative disorder.
  • Participants with organ damage caused by systemic mastocytosis.
  • Participants with clinically significant, uncontrolled cardiovascular disease.
  • Participants with a QTcF interval >470 msec for females or >450 msec for males.
  • Participants with a history of primary malignancy diagnosed or treated within the past 3 years, except certain skin cancers and localized prostate cancer.
  • Participants who received cytoreductive or antibody therapies within specified time frames before screening.
  • Participants who have had radiotherapy or PUVA therapy within 14 days before screening.

AI-Screening

AI-Powered Screening

Complete this quick 3-step screening to check your eligibility

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Trial Site Locations

Total: 64 locations

1

University of Alabama at Birmingham

Birmingham, Alabama, United States, 35294

Actively Recruiting

2

David Geffen School of Medicine at UCLA

Los Angeles, California, United States, 90095

Actively Recruiting

3

Stanford Cancer Institute

Palo Alto, California, United States, 94305

Actively Recruiting

4

UCHealth Blood Disorders and Cell Therapies Center - Anschutz Medical Campus

Aurora, Colorado, United States, 80045

Actively Recruiting

5

Winship Cancer Institute, Emory University

Atlanta, Georgia, United States, 30322

Actively Recruiting

6

Brigham and Women's Hospital

Boston, Massachusetts, United States, 02115

Actively Recruiting

7

Michigan Medicine University of Michigan

Ann Arbor, Michigan, United States, 48109

Actively Recruiting

8

Mayo Clinic

Rochester, Minnesota, United States, 55902

Actively Recruiting

9

Roswell Park Cancer Institute

Buffalo, New York, United States, 14263

Actively Recruiting

10

Columbia University Medical Center

New York, New York, United States, 10032

Actively Recruiting

11

Duke Asthma, Allergy and Airway Center

Durham, North Carolina, United States, 27705

Actively Recruiting

12

University of Cincinnati Medical Center

Cincinnati, Ohio, United States, 45219

Actively Recruiting

13

The University of Texas, MD Anderson Cancer Center

Houston, Texas, United States, 77030

Actively Recruiting

14

Huntsman Cancer Institute, University of Utah

Salt Lake City, Utah, United States, 84112

Actively Recruiting

15

Consultorios Medicos Dr. Doreski - Fundacion Respirar

Buenos Aires, Argentina, 1426

Actively Recruiting

16

Princess Alexandra Hospital

Woolloongabba, Queensland, Australia

Actively Recruiting

17

The Alfred Hospital

Melbourne, Victoria, Australia, 3004

Actively Recruiting

18

Kepler Universitatsklinikum, Med Campus III. Clinic of Internal Medicine 3 - Hematology and Oncology

Linz, Austria, 4021

Actively Recruiting

19

Unitversitair Ziekenhuis Antwerpen

Edegem, Antwerpen, Belgium

Actively Recruiting

20

CHU Tivoli

La Louvière, Belgium, 7100

Actively Recruiting

21

Fakultní nemocnice Královské Vinohrady, Hematologická klinika 3. LF UK v Praze a FNKV

Prague, Czechia, 100 34

Actively Recruiting

22

CHU Amiens-Picardie

Amiens, France, 80000

Actively Recruiting

23

CHU de Caen

Caen, France

Actively Recruiting

24

CHU Grenoble

Grenoble, France, 38043

Actively Recruiting

25

CHU de Limoges

Limoges, France, 87042

Actively Recruiting

26

CHU de Nantes

Nantes, France, 44093

Actively Recruiting

27

Hôpital de la Pitié Salpétrière

Paris, France, 75013

Actively Recruiting

28

Hôpital Necker - Départementd 'HématologieA dultes

Paris, France, 75015

Actively Recruiting

29

CHU de Poitiers

Poitiers, France, 86000

Actively Recruiting

30

CHU Toulouse - Hopital Larrey

Toulouse, France

Actively Recruiting

31

Universitätsklinikum RWTH Aachen Klinik für Hämatologie, Onkologie, Hämostaseologie und Stammzelltransplantation

Aachen, Germany

Actively Recruiting

32

Charité - Universitätsmedizin Berlin Institute of Allergology

Berlin, Germany, 12203

Actively Recruiting

33

University Clinic Erlangen

Erlangen, Germany, 91054

Actively Recruiting

34

University Clinic Hamburg Eppendorf

Hamburg, Germany, 20246

Actively Recruiting

35

Universitätsmedizin Mannheim III. Medizinische Klinik Universität Heidelberg Medizinische Fakultät Mannheim

Mannheim, Germany, 68167

Actively Recruiting

36

LMU Klinikum

Munich, Germany, 80377

Actively Recruiting

37

University General Hospital - General Hospital of West Attica

Chaïdári, Greece, 12462

Actively Recruiting

38

General Hospital of Thessaloniki "G. Papanikolaou"

Thessaloniki, Greece, 57010

Actively Recruiting

39

UOC Ematologia

Milan, Lombardy, Italy, 20122

Actively Recruiting

40

SOD Ematologia (Ambulatori)- AOUC Azienda Ospedaliero Universitaria Careggi

Florence, Tuscany, Italy, 50134

Actively Recruiting

41

Unita Operativa di Ematologia AOU Policlinico S. Orsola-Malpighi

Bologna, Italy, 40138

Actively Recruiting

42

AOU Policlinico G.Rodolico - San Marco

Catania, Italy, 95123

Actively Recruiting

43

S.C. Ematologia Fondazione I.R.C.C.S. Policlinico San Matteo

Pavia, Italy, 27100

Actively Recruiting

44

S.S.D. Immunologia Clinica e Allergologia Azienda Ospedaliera Universitaria San Giovanni di Dio e Ruggi d'Aragona

Salerno, Italy, 84131

Actively Recruiting

45

Unità Operativa di Allergologia Azienda Ospedaliera Universitaria Integrata di Verona

Verona, Italy, 37126

Actively Recruiting

46

ErasmusMC

Rotterdam, South Holland, Netherlands, 3015 GD

Actively Recruiting

47

University Medical Center Groningen

Groningen, Netherlands, 9713 GZ

Actively Recruiting

48

Oslo University Hospital

Oslo, Norway, N-0424

Actively Recruiting

49

Uniwersyteckie Centrum Kliniczne Klinika Alergologii

Gdansk, Poland, 80-214

Actively Recruiting

50

Centro Hospitalar de Lisboa Central, E.P.E. - Hospital de Santo Antonio dos Capuchos

Lisbon, Portugal, 1169-050

Actively Recruiting

51

CHUPorto, EPE - Hospital de Santo António

Porto, Portugal, 4099-001

Actively Recruiting

52

Centro Hospitalar Universitario Sao Joao, E.P.E.

Porto, Portugal, 4200-139

Actively Recruiting

53

Hospital Universitario Vall d'Hebron

Barcelona, Spain

Actively Recruiting

54

Hospital Universitario Ramon y Cajal

Madrid, Spain, 28034

Actively Recruiting

55

Hospital Virgen del Valle - Instituto de Estudios de Mastocitosis de Castilla-La Mancha

Toledo, Spain, 45071

Actively Recruiting

56

Uppsala University Hospital

Uppsala, Sweden, 751 85

Actively Recruiting

57

University Hospital Basel

Basel, Switzerland, C-4031

Actively Recruiting

58

Luzerner Kantonsspital

Lucerne, Switzerland, 6000

Actively Recruiting

59

University Hospital of Wales

Cardiff, Wales, United Kingdom, CF14 4XW

Actively Recruiting

60

University Hospital of Wales

Cardiff, United Kingdom, CF14 4XW

Actively Recruiting

61

University College London Hospitals (UCLH), Haematology Cancer Clinical Trials Unit

London, United Kingdom, NW1 2PG

Actively Recruiting

62

Guy's and St Thomas's NHS Foundation Trust

London, United Kingdom, SE1 7EH

Actively Recruiting

63

Cancer and Haematology Centre

Oxford, United Kingdom, OX3 7LE

Actively Recruiting

64

University Hospital Plymouth NHS Trust

Plymouth, United Kingdom, PL6 8DH

Actively Recruiting

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Research Team

B

Blueprint Medicines

CONTACT

How is the study designed?

Study Type

INTERVENTIONAL

Masking

QUADRUPLE

Allocation

RANDOMIZED

Model

PARALLEL

Primary Purpose

TREATMENT

Number of Arms

10

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