This is a randomized, double-blind study of rilzabrutinib in patients with persistent or chronic ITP, with an average platelet count of <30,000/μL (and no single platelet count >35,000/μL) on two counts at least 5 days apart in the 14 days before treatment begins. Patients will receive rilzabrutinib or placebo 400mg twice daily.
For each patient, the study will last up to 60 weeks from the start of the Screening Period to the End of Study (EOS) visit. This includes Screening (up to 4 weeks) through a 12 to 24-week Blinded Treatment Period followed by a 28-week Open-Label Period. Followed by a 4-week post dose follow-up.
Patients who respond per specified criteria at the end of the Open-Label Period will be able to enter the Long-Term Extension (LTE) where they will continue to receive treatment until the last patient who enters the LTE has completed 12 months.
A Phase 3, Multicenter, Randomized, Double-Blind, Placebo Controlled, Parallel-Group Study With an Open-Label Extension to Evaluate the Efficacy and Safety of Oral Rilzabrutinib (PRN1008) in Adults and Adolescents With Persistent or Chronic Immune Thrombocytopenia (ITP)