Acalabrutinib Monotherapy vs Investigator's Choice of Treatment in Patients With CL Leukaemia and Heart Failure

This study is comparing acalabrutinib (a targeted oral cancer pill) against the doctor's standard choice of treatment for patients with chronic lymphocytic leukemia (CLL) — a slow-growing blood cancer — who also have reduced heart pumping function (heart failure with low ejection fraction). **You may be eligible if...** - You are 18 or older with a confirmed CLL diagnosis - Your heart's pumping ability is below 50% (measured by an echocardiogram) - You have either never been treated for CLL, or your CLL has come back after previous treatment - You have received no more than 2 prior CLL treatments - Your blood counts and organ function are within acceptable ranges **You may NOT be eligible if...** - Your heart pumping function is normal (50% or above) - You have received more than 2 prior CLL treatments - You have a history of certain bleeding problems or are on blood thinners that cannot be safely adjusted - You have another active cancer requiring treatment Talk to your doctor to see if this trial is right for you.