Among patients with relapsed/refractory chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), zanubrutinib appears to yield superior clinical outcomes to ibrutinib, according to research presented at the Annual Meeting of the Society of Hematologic Oncology (SOHO).
Researchers designed the randomized phase 3 ALPINE trial (ClinicalTrials.gov Identifier: NCT03734016) to compare the safety and efficacy of zanubrutinib and ibrutinib among patients with relapsed/refractory CLL/SLL. At the 2022 SOHO meeting, the authors presented results of a preplanned interim analysis.
Overall, 415 patients were randomly assigned 1:1 to receive ibrutinib or zanubrutinib. Patients were stratified by age, refractory disease status, and the presence of 17p deletion or TP53 mutation. The interim analysis was conducted at approximately 1 year post-enrollment for all patients.
Most patients were at least 65 years of age (62.3% in the zanubrutinib group and 61.5% in the ibrutinib group), most were men (68.6% and 75%, respectively), but few had received more than 3 prior lines of therapy (7.2% and 10.1%, respectively). TP53 mutations without 17p deletion were noted in 8.2% of patients in the zanubrutinib group and 5.8% of patients in the ibrutinib group.
The median follow-up was 15 months. At this point, the overall response rate was 78.3% in the zanubrutinib group and 62.5% in the ibrutinib group (2-sided P =.0006). Improved overall response rates were noted among patients with 11q deletion or 17p deletion.
The 12-month progression-free survival rate was 94.9% in the zanubrutinib group and 84.0% in the ibrutinib group. The 12-month overall survival rate was 97.0% and 92.7%, respectively.
The rate of major bleeding was lower in the zanubrutinib group than in the ibrutinib group (2.9% and 3.9%, respectively). The same was true for toxicity leading to discontinuation (7.8% vs 13.0%), grade 3 or worse infection (12.7% vs 17.9%), and death (3.9% vs 5.8%). However, neutropenia occurred more frequently in the zanubrutinib group (28.4% vs 21.7%).
Brown JR, Hillmen P, Eichhorst B, et al. First interim analysis of ALPINE study: results of a phase 3 randomized study of zanubrutinib vs ibrutinib in patients with relapsed/refractory (R/R) chronic lymphocytic leukemia/ small lymphocytic lymphoma (CLL/SLL). Annual Meeting of the Society of Hematologic Oncology (SOHO); September 28-October 1, 2022. Abstract CLL-115.
This article originally appeared on Hematology Advisor