Jacqueline Barrientos, MD, from the North Shore-Long Island Jewish Health System in New York, discusses the drug acalabrutinib (ACP-196), a second generation Bruton’s tirosine kinase (BTK) inhibitor that demonstrates reduced off-target effects. Dr Barrientos provides an overview of the Phase I study, where 965 of patients responded to treatment, including patients that have been through partial remission with lymphocytosis.