Zanubrutinib or Ibrutinib in Relapsed or Refractory Chronic Lymphocytic Leukemia

In a multinational, phase 3, head-to-head trial, ibrutinib, a Bruton’s tyrosine kinase (BTK) inhibitor, was compared with zanubrutinib, a BTK inhibitor with greater specificity, as treatment for relapsed or refractory chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL). In prespecified interim analyses, zanubrutinib was superior to ibrutinib with respect to overall response (the primary end point). Data from the final analysis of progression-free survival are now available.