An established therapy for relapsed/refractory (R/R) mantle cell lymphoma is a Bruton tyrosine kinase (BTK) inhibitor (MCL). Zanubrutinib, a highly selective BTK inhibitor, has been authorized for MCL patients who have had at least one previous treatment. The findings of the multicenter, open-label, phase 2 registration study of zanubrutinib’s long-term safety and effectiveness were presented to researchers. The patients (n=86) were given 160 mg of zanubrutinib twice a day. The overall response rate (ORR) was the main outcome, as determined by Lugano 2014. The ORR was 83.7% after a median follow-up of 35.3 months, with 77.9% reaching complete response (CR); the median duration of response was not met. PFS (progression-free survival) was 33.0 months on average (95% CI, 19.4-NE). 

PFS and overall survival (OS) rates at 36 months were 47.6% (95% CI, 36.2-58.1) and 74.8%(95% CI, 63.7-83.0), respectively. With longer follow-up, the safety profile remained basically constant. Neutrophil count dropped (46.5%), upper respiratory tract infection (38.4%), rash (36.0%), white blood cell count decreased (33.7%), and platelet count decreased (32.6%) were the most prevalent all-grade adverse events (AEs); the majority were grade 1/2 occurrences. Neutrophil count drop (18.6%) and pneumonia were the most prevalent grade≥3 AEs (10%). (12.8% ). Infection, neutropenia, and bleeding rates were greatest in the first 6 months of treatment and thereafter reduced. 

There were no reports of atrial fibrillation/flutter, grade ≥3 cardiac adverse events, second primary malignancies, or tumor lysis syndrome. In R/R MCL, zanubrutinib showed persistent responses and a favorable safety profile during extended follow-up.

Reference:ashpublications.org/blood/article/139/21/3148/484435/Zanubrutinib-in-relapsed-refractory-mantle-cell

Author