An observational study in Indolent Systemic Mastocytosis, sponsored by Blueprint Medicines Corporation. Recruiting at 12 sites in Germany. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-07.
Sponsored by Blueprint Medicines Corporation (part of Sanofi) · Observational
This is a non-interventional study assessing the effectiveness of avapritinib (BLU-285) in the management of ISM in real-world settings in Germany. The study also seeks to address the existing data gap in the natural history and management of participants with ISM.
The study is designed to follow each participant up to a maximum of 24 months.
56 studies on the registry are indexed under Mastocytosis, Systemic; 16 are open to participants now.
This study's planned enrollment of 80 is below the median of 155 across 18 observational studies indexed under Mastocytosis, Systemic.
Browse Mastocytosis, Systemic studies →Blueprint Medicines Corporation is the lead sponsor of 32 studies on the registry; 6 are open to participants now.
Of its 14 completed or terminated interventional studies of FDA-regulated products, 3 (21%) have results posted.
First submitted after Blueprint Medicines Corporation became part of Sanofi.
Counted across the registry records on this site, refreshed daily.
Adult participants with ISM with moderate to severe symptoms inadequately controlled on symptomatic treatment, who are initiating treatment with commercial avapritinib according to the German approved label.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Participants will receive avapritinib as part of their treatment plan with their healthcare practitioner (HCP) and in accordance with the Summary of Product Characteristics (SmPC).
Drug: Avapritinib
Avapritinib will be administered as an oral tablet.
Also known as: Ayvakyt, BLU-285
Change From Baseline in Mastocytosis Control-quality of Life (MC-QoL) Questionnaire Score at Month 6
Time frame: Baseline, Month 6
Socio-demographic Variable: Participant Age
Time frame: Baseline (Day -30 to Day -1)
Socio-demographic Variable: Participant Gender
Time frame: Baseline (Day -30 to Day -1)
Socio-demographic Variable: Participant Ethnicity
Time frame: Baseline (Day -30 to Day -1)
Socio-demographic Variable: Participant Race
Time frame: Baseline (Day -30 to Day -1)
Baseline Serum Tryptase and KIT D816V Variant Allele Fraction (VAF)
Time frame: Baseline (Day -30 to Day -1)
Number of Participants With Prior Medical History of Anaphylaxis
Time frame: Baseline (Day -30 to Day -1)
Number of Participants with Comorbidity
Time frame: Baseline up to Month 24
Number of Participants Initiating a New ISM-directed Medication, Discontinuing an ISM-directed Medication, and With Dose Increases or Decreases for ISM-directed Medications
Time frame: Baseline up to Month 24
Number of Participants Prescribed a Life Support Kit
Time frame: Baseline up to Month 24
Change From Baseline in Mastocytosis Activity Score (MAS) at Months 3, 6, 12, 18, and 24
Time frame: Baseline, Months 3, 6, 12, 18, and 24
Change From Baseline in MC-QoL Questionnaire Score at Months 3, 6, 12, 18, and 24
Time frame: Baseline, Months 3, 6, 12, 18, and 24
Change From Baseline in Mastocytosis Control Test (MCT) Score at Months 3, 6, 12, 18, and 24
Time frame: Baseline, Months 3, 6, 12, 18, and 24
Time to Response as Assessed by MAS
Time frame: Baseline up to Month 24
Change From Baseline in Serum Tryptase at Months 3, 6, 12, 18, and 24
Time frame: Baseline, Months 3, 6, 12, 18, and 24
Number of Participants With Anaphylaxis Requiring Hospitalization, Emergency Room (ER) Visit, Epinephrine Autoinjector Use, or Other Medication
Time frame: Baseline up to Month 24
Number of Participants Meeting the Definition of Polypharmacy (Use of Multiple Medications Simultaneously; Typically, 3 or More Symptom-directed Prescription Drugs)
Time frame: Baseline up to Month 24
Number of Participants With ISM-related Hospital Visits and ER Visits
Time frame: Baseline up to Month 24
Number of Participants With Changes in ISM Symptom-directed Therapies
Time frame: Baseline up to Month 24
Number of Participants With Dose Modifications and Study/Treatment Discontinuations
Time frame: Baseline up to Month 24
Started Dec 2025 (actual). Primary completion is estimated for Dec 2028, 35 months after the start.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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