Abstract
BACKGROUND: There are no head-to-head studies comparing the efficacy of the Bruton tyrosine kinase inhibitors, zanubrutinib and acalabrutinib, in relapsed or refractory chronic lymphocytic leukemia (R/R CLL). OBJECTIVE: To compare the relative efficacy of zanubrutinib and acalabrutinib in R/R CLL using indirect treatment comparison. DESIGN: An unanchored matching-adjusted indirect comparison (MAIC) was performed. METHODS: Individual patient-level data from ALPINE (zanubrutinib) were reweighted using prognostic/effect-modifying variables to match aggregate data from ASCEND (acalabrutinib). MAIC outcomes included investigator-assessed progression-free survival (PFS-INV), overall survival (OS), and complete response (CR). RESULTS: Post-matching, PFS-INV was improved significantly for zanubrutinib versus acalabrutinib (hazard ratio (HR) = 0.68 (95% confidence interval (CI): 0.46-0.99); p = 0.0448) and OS showed a trend toward improvement for zanubrutinib (HR = 0.60; 95% CI: 0.35-1.02, p = 0.0575). CR was significantly higher for zanubrutinib versus acalabrutinib (odds ratio = 2.90 (95% CI: 1.13-7.43); p = 0.0270). CONCLUSION: Zanubrutinib was associated with a significant PFS-INV and CR advantage over acalabrutinib, with a trend toward improvement in OS.