A Randomized Phase II Study Of Bruton Tyrosine Kinase Inhibitor With Or Without Venetoclax In Veterans With Chronic Lymphocytic Leukemia (CLL)/Small Lymphocytic Lymphoma (SLL)

People who have chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL) are often treated with ibrutinib, acalabrutinib, or zanubrutinib. These are pills that are taken by mouth. This type of pill is called "Bruton Tyrosine Kinase Inhibitor" or BTKi. Another treatment for CLL/SLL is a different pill called venetoclax. The purpose of this study is to compare continuing the current treatment with BTKi alone, as long as it is working, to another arm of treatment which adds venetoclax to the current treatment (BTKi), for one year. After one year, both pills in this arm of treatment would be stopped and the participants will be closely monitored.