NCT07264959 · Blueprint Medicines Corporation
An Observational Study in Participants With Indolent Systemic Mastocytosis (ISM)
What this study is about
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.
View original scientific description
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.
Primary outcome measures
Baseline Demographics
Time frame: Baseline (Month 1)
Change From Baseline in Patient-Reported Outcomes Scores
Time frame: Baseline up to Month 61
Change From Baseline in Serum KIT D816V Variant Allele Frequency (VAF)
Time frame: Baseline up to Month 61
Change From Baseline in Serum Tryptase
Time frame: Baseline up to Month 61
Change From Baseline in Indolent Systemic Mastocytosis (ISM) Symptom-Directed Therapies
Time frame: Baseline up to Month 61
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
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.
Where
- Chestnut Hill, Massachusetts
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Apr 22, 2026 · Source of record for eligibility and locations