In a study of treatment in patients with chronic lymphocytic leukaemia, the addition of AZB to cyclophosphamide and chlorbutin in patients with stage III B-cell lymphocytic leukaemia saw positive changes in CD3+ and CD4+ T-cells, natural killer (NK) cell counts, increased phagocytic activity of neutrophils and immunoglobulin levels over time were also noted. This evidence concerns the gene CD4 and B-cell chronic lymphocytic leukemia.