ISM is an overproduction of mutated and hyperactive mast cells creating disruption throughout the body1,2

The KIT D816V mutation, which drives the overproduction of abnormal mast cells, is found in ~95% of ISM cases.1,3-5

The mutated, hyperactive mast cells release mediators that
can lead to various debilitating symptoms across systems1,2,6

Body figure outline

These symptoms represent the clinical spectrum of ISM. Symptoms may vary in individual patients.

65%

of patients reported experiencing nervous system disorders 7*

80%

of patients reported experiencing GI disorders 7*

76%

of patients reported experiencing skin and subcutaneous tissue disorders 7*

* Data based on ongoing medical history events in the PIONEER study (N=212). Events ≥10% in 1 or both trial arms from 3 of the organ classes include pruritus, urticaria pigmentosa, urticaria, rash maculo-papular for skin and subcutaneous tissue disorders; headache, dizziness, migraine, memory impairment, disturbance in attention for nervous system disorders; and diarrhea, abdominal pain, nausea, gastroesophageal reflux disease, abdominal distension, constipation for gastrointestinal disorders.7

GI=gastrointestinal; ISM=indolent systemic mastocytosis; KIT=KIT proto-oncogene, receptor tyrosine kinase.

See how ISM impacts the lives of patients

BURDEN OF ISM

Patient portrayal

Indolent systemic mastocytosis patient and caregiver

References: 1. Pardanani A. Am J Hematol. 2023;98(7):1097-1116. 2. Gülen T et al. J Intern Med. 2016;279(3):211-228. 3. Kristensen T et al. Am J Hematol. 2014;89(5):493-498. 4. Garcia-Montero AC et al. Blood. 2006;108(7):2366-2372. 5. Ungerstedt J et al. Cancers. 2022;14(16):3942. 6. Akin C, ed. Mastocytosis: A Comprehensive Guide. Springer; 2020. 7. Data on file. Blueprint Medicines Corporation, Cambridge, MA. 2023.