Progression-free survival is significantly longer with zanubrutinib than ibrutinib among patients with relapsed or refractory chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL), according to a study. Jennifer R. Brown, M.D., Ph.D. and colleagues randomly assigned patients with relapsed or refractory CLL or SLL who had undergone one previous course of therapy to receive either zanubrutinib or ibrutinib until disease progression or unacceptable toxic effects. Progression-free survival was assessed to determine whether zanubrutinib was non-inferior to ibrutinib in this final analysis; the superiority of zanubrutinib was assessed if non-inferiority was established. The researchers found that among 652 patients, zanubrutinib...