Bruton's tyrosine kinase inhibition in ITP: Wayrilz (rilzabrutinib) as a disease-modifying strategy

Immune thrombocytopenia (ITP) is an acquired autoimmune disorder characterized by immune-mediated platelet destruction and impaired platelet production, leading to bleeding risk, morbidity, and reduced quality of life. Incomplete responses, adverse effects, and relapses are the limitations of current treatments, which include corticosteroids, intravenous immunoglobulin, rituximab, and thrombopoietin receptor agonists. On 29 August 2025, the U.S. Food and Drug Administration (FDA) approved Wayrilz (rilzabrutinib), a first-in-class oral Bruton's tyrosine kinase inhibitor, for the treatment of adult patients with chronic or persistent ITP who have had an insufficient response to previous treatments. Through modulation of both Fc receptor and B-cell receptor signaling, the agent aims to address disease pathophysiology as a treatment that is disease-modifying in nature rather than simplistically dealing with symptoms. Clinical trials, including the key LUNA 3 trial, have shown good efficacy and safety, with durable platelet responses and minimal severe adverse events. This editorial examines rilzabrutinib's scientific justification, clinical data, comparative analysis, side effects, financial ramifications, and potential applications in the treatment of ITP.