This study is investigating targeted therapy (bezuclastinib) for the treatment of advanced systemic mastocytosis (AdvSM), including people with Aggressive SM( ASM), SM with associated haematologic neoplasm (SM-AHN), and Mast Cell Leukaemia (MCL)A Phase 2 Open-Label, Multicenter Clinical Study of the Safety, Efficacy, Pharmacokinetic, and Pharmacodynamic Profiles of CGT9486 as a Single Agent in Patients With Advanced Systemic Mastocytosis

Exclusion

1. Persistent toxicity from previous therapy for Advanced Systemic Mastocytosis that has not resolved to ≤ Grade 1
2. Associated hematologic neoplasm requiring immediate antineoplastic therapy
3. Clinically significant cardiac disease
4. Known positivity for the FIP1L1 PDGFRA fusion. Patients with eosinophilia without detectable KIT D816V mutation must also lack the PDGFRA fusion mutation prior to enrollment
5. Seropositive for human immunodeficiency virus (HIV) 1 or 2, or positive for hepatitis B surface antigen or hepatitis C virus (HCV) antibody
6. History of clinically significant bleeding event within 30 days before the first dose of study drug or need for therapeutic anticoagulation on study
7. Diagnosed with or treated for malignancy other than the disease under study within the prior 3 years before enrollment
8. Received any cytoreductive therapy or any investigational agent less than 14 days, and for cladribine, interferon alpha, pegylated interferon, and any antibody therapy less than 28 days, before screening bone marrow biopsy
9. Received hematopoietic growth factor support within 14 days before the first dose of study drug
10. Received strong CYP3A4 inhibitors or inducers within 14 days or 5 drug half-lives, whichever is longer, before the first dose of study drug.
11. Need for treatment with high dose steroids.