Study to Evaluate Rilzabrutinib in Adults and Adolescents With Persistent or Chronic Immune Thrombocytopenia (ITP)

Inclusion criteria

• ✓. Male and female with primary ITP with duration of \>6 months in pediatric participants aged 12 to \<18 years (pediatric participants aged 10 to \<12 years will be enrolled in the EU \[EEA countries\] only) and duration of \>3 months in ages 18 years and above
• ✓. Patients who had a response (achievement of platelet count ≥50,000/µL) to IVIg/anti-D or CSs that was not sustained and who have documented intolerance, insufficient response or any contra-indication to any appropriate courses of standard of care ITP therapy
• ✓. An average of 2 platelet counts at least 5 days apart of \<30,000/µL during the Screening period and no single platelet count \>35,000/µL, within 14 days prior to the first dose of study drug.
• ✓. Adequate hematologic, hepatic, and renal function (absolute neutrophil count ≥1.5 X 10\^9/L, AST/ALT ≤1.5 x upper limit of normal \[ULN\], albumin ≥3 g/dL, total bilirubin ≤1.5 x ULN \[unless the patient has documented Gilbert syndrome\], glomerular filtration rate \>50 \[Cockcroft and Gault method for adult and Bedside Schwartz Equation for Pediatric participants\])
• ✓. Hemoglobin \>9 g/dL within 1 week prior to Study Day 1
• ✓. All contraceptive use by men and women should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies
• ✓. Patients must be able to provide written informed consent or informed assent with corresponding informed consent obtained from the patient's guardian and agree to the schedule of assessments