Rilzabrutinib and Bruton tyrosine kinase inhibition for the treatment of persistent or chronic immune thrombocytopenia.

INTRODUCTION

Immune thrombocytopenia (ITP) is an acquired autoimmune hematologic disorder characterized by autoantibody-mediated platelet destruction and impaired platelet production, resulting in thrombocytopenia and an increased risk of bleeding complications. Many patients will require additional treatment beyond first-line corticosteroids. In 2025, the US FDA approved rilzabrutinib, a Bruton tyrosine kinase inhibitor, for the treatment of adult patients with persistent or chronic ITP who have had an insufficient response to a previous treatment.

AREAS COVERED: This review summarizes the pharmacology, efficacy, and safety of rilzabrutinib for the treatment of persistent or chronic ITP, followed by an expert opinion of the authors. PubMed was searched for relevant literature up to September 2025.

EXPERT OPINION: The approval of rilzabrutinib represents an important advancement in the treatment of ITP and adds to the therapeutic armamentarium for this patient population. While rilzabrutinib has demonstrated efficacy compared to placebo in previously treated ITP patients, there is a lack of direct comparisons with other treatment options. The safety profile of rilzabrutinib differs from other BTK inhibitors approved for B-cell malignancies. Rilzabrutinib is subject to numerous drug-drug interactions, and careful selection of this agent and review of concomitant medications will be important to ensure its safe and effective use.