Chronic lymphocytic leukemia (CLL) is an abnormal growth of the B-lymphocyte, a type of cell in the immune system. The immune system helps us to fight infections and clean out waste products from the body. We believe that these typical elements that our immune systems encounter signal, or tell, the leukemia cells to multiply.

One way that these signals are given is through a special mechanism in the B-lymphocyte called a toll like receptor (TLR). Hydroxychloroquine is a drug that has been shown to interfere with the TLR and stop the signal from going through. By interrupting this signal, hydroxychloroquine was shown to stop CLL cells from growing in laboratory containers.

The purpose of this study is to see if hydroxychloroquine will prevent CLL cells from growing in people with CLL.