An Observational Study in Participants With Indolent Systemic Mastocytosis (ISM)

An Observational Study in Patients With Indolent Systemic Mastocytosis

Status

Recruiting

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT07264959

Enrollment

150

Registered

2025-12-04

Start date

2026-04-15

Completion date

2032-12-01

Last updated

2026-09-04

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Indolent Systemic Mastocytosis

Keywords

ISM, Avapritinib, BLU-285, Selective KIT mutation-targeted tyrosine kinase inhibitor, Tyrosine kinase inhibitor, Mastocytosis, Neoplastic mast cells

Brief summary

This is a Phase 4, non-interventional, observational study to collect detailed data on the clinical characteristics, clinical outcomes and medical management of ISM in real-world settings. The study will describe the demographic and clinical characteristics of ISM participants, including anaphylaxis and bone manifestations in ISM. Quality of life and disease control will be assessed through participant questionnaires. The study will also evaluate real world ISM treatment management, including use of avapritinib.

Interventions

None listed

Study design

Observational model

COHORT

Time perspective

PROSPECTIVE

Eligibility

Sex/Gender

ALL

Age

18 Years to No maximum

Healthy volunteers

Inclusion criteria

* Male or female adult participants (≥ 18 years of age) with a diagnosis of ISM according to the World Health Organization (WHO) diagnostic criteria * Participant is currently being treated or plans to be treated with symptom-directed therapies and/or avapritinib for ISM.

Exclusion criteria

* Participants with advanced systemic mastocytosis (AdvSM) or another associated hematologic neoplasm * Participants with smoldering systemic mastocytosis * Ongoing participation in interventional studies in systemic mastocytosis (SM) at the time of enrollment * Participants currently receiving treatment with a KIT inhibitor other than avapritinib at the time of enrollment.

Design outcomes

Primary

Measure	Time frame
Baseline Demographics	Baseline (Month 1)
Change From Baseline in Patient-Reported Outcomes Scores	Baseline up to Month 61
Change From Baseline in Serum KIT D816V Variant Allele Frequency (VAF)	Baseline up to Month 61
Change From Baseline in Serum Tryptase	Baseline up to Month 61
Change From Baseline in Indolent Systemic Mastocytosis (ISM) Symptom-Directed Therapies	Baseline up to Month 61

Countries

United States

Contacts

CONTACTBlueprint Medicines

medinfo@blueprintmedicines.com1-888-258-7768

CONTACTBlueprint Medicines, EU Contact

medinfoeurope@blueprintmedicines.com+31 85 064 4001

Outcome results