Byrd JC, Hillmen P, Ghia P, et al. - Researchers compared acalabrutinib and ibrutinib (Bruton's tyrosine kinase inhibitors) in chronic lymphocytic leukemia (CLL) patients in this open-label, randomized, noninferiority, phase III trial. They randomized patients with previously managed CLL with centrally confirmed del(17)(p13.1) or del(11)(q22.3) to receive oral acalabrutinib 100 mg twice daily or ibrutinib 420 mg once daily until progression or unacceptable toxicity. Findings of this first direct comparison of less vs more selective Bruton's tyrosine kinase inhibitors in CLL revealed that a noninferior progression-free survival and fewer cardiovascular adverse events were associated with treatment with acalabrutinib.