Incidence and Management of Tirabrutinib-associated Cutaneous Adverse Events: A Case Series

Cutaneous adverse events associated with tirabrutinib have been reported in clinical trials; however, their overall incidence and severity vary, and real-world data remain limited. This study aimed to assess the incidence and management of tirabrutinib-associated cutaneous adverse events in patients with primary central nervous system lymphoma (PCNSL). This single-center case series included patients with PCNSL who received tirabrutinib treatment between March 1, 2020, and February 29, 2024. Cutaneous adverse events were evaluated using the Common Terminology Criteria for Adverse Events, version 5.0. Patient characteristics, tirabrutinib dosage, concomitant medications, disease severity, time to onset, treatment, and outcomes were analyzed. Seven patients (mean age: 71.1 years, range, 52-88 years) were included herein. Skin disorders were observed in 5 patients (71.4%), including maculopapular rash (grade 2) in 3 patients, erythema multiforme (grade 3) in 1 patient, and eczema-like lesions (grade 2) in 1 patient. The median onset was 22.4 d (range: 1-56 d), with 4 cases occurring within 1 month. Treatments included oral antihistamines (4 cases) and topical corticosteroids (4 cases). One patient discontinued tirabrutinib treatment because of severe cutaneous adverse events. Tirabrutinib-associated cutaneous adverse events were common but manageable, except in 1 case. As most cutaneous adverse events develop within a month, early monitoring is crucial. Large-scale studies are needed to assess the risk factors and preventive strategies for tirabrutinib-associated cutaneous adverse events.