A phase I/II study of Xcellerated T Cells in patients with chronic lymphocytic leukemia

2511 Background: T cells from CLL pts can be activated & expanded ex vivo using the Xcellerate Process, in which peripheral blood mononuclear cells (PBMC) are incubated with anti-CD3 & anti-CD28 antibody-coated magnetic beads (Xcyte Dynabeads). With this process, anergic T cells from CLL pts can be activated, leading to upregulation of important immune molecules on leukemic B cells & leukemic cell apoptosis (Bonyhadi et al., J. Immunol, in press). Methods: A total of 17 pts with high risk or symptomatic/progressive intermediate-risk disease were divided into 3 cohorts which were treated with increasing Xcellerated T Cell (XTC) doses: 10 x 109(n=3), 30 x 109 (n=3), and 60–100 x 109(n=11). Results: Prior treatments included chemotherapy ± monoclonal antibody treatment (n=10), investigational vaccine (n=3), steroids (n=1), and no prior therapy (n=3). There was one serious adverse event (SAE) of atrial fibrillation, which occured 17 days post-infusion & was unlikely related to treatment. T cell counts increas...