Zanubrutinib or ibrutinib in relapsed or refractory chronic lymphocytic leukemia
The phase 3 ALPINE trial, which compared ibrutinib to zanubrutinib (both BTK inhibitors) in patients with relapsed or refractory CLL, demonstrated superior progression-free survival (PFS) with zanubrutinib compared to ibrutinib at a median follow up of approximately 30 months. At 24 months from initiation of treatment, investigator-assessed PFS was 78.4% with zanubrutinib and 65.9% with ibrutinib. PFS ratio for disease progression or death at 24 months was 0.65 (95% CI: 0.49 to 0.86; P = 0.002) with zanubrutinib compared to ibrutinib. Grade > 3 adverse events included slightly higher rates of neutropenia (16.0% vs. 13.9%) and hypertension (14.8% vs. 11.1%) with zanubrutinib compared to ibrutinib, and slightly higher rates of atrial fibrillation with ibrutinib (3.7%) compared to zanubrutinib (1.9%).