BLUE BELL, Pa., Dec. 6, 2012 /PRNewswire/ -- Inovio Pharmaceuticals, Inc. (NYSE MKT: INO) announced today that preliminary results of a phase II clinical trial to treat leukemia with a WT1 DNA vaccine delivered with Inovio's proprietary electroporation delivery system showed robust vaccine-specific antibody responses in all vaccinated subjects evaluated to date. Furthermore, T cell immune responses, including those of the "killer T cells," were detected. Antibody and T cell responses are strong signals of the DNA vaccine's potential to treat the disease. The data was presented today at an international conference, DNA Vaccines 2012, in San Diego, Ca, by Dr. Christian H. Ottensmeier, MD, PhD, the trial's principal investigator and Professor of Experimental Cancer Research at the University of Southampton, UK. These interim results, from eight patients, are part of a phase II trial that will enroll 31 patients in its chronic myelogenous leukemia (CML) arm. To date, 14 CML patients have been enrolled while another 13 unvaccinated CML patients have been enrolled to serve as a control group. The vaccine has been shown to be safe overall and well-tolerated in the trial subjects. A detailed analysis of T cell immune responses as well as the impact of the vaccination on the molecular marker, BCR-ABL, which is a specific chromosomal abnormality that is associated with chronic myelogenous leukemia (CML) disease, will be performed. As a result of the favorable safety and immunogenicity profiles observed in the CML vaccinated group, the trial is now open to enroll the acute myeloid leukemia (AML) clinical trial arm, with a total target of 37 subjects in each of the vaccinated and control groups. This open-label, multi-center phase II clinical trial is evaluating a DNA vaccine-based immune therapy to treat these two types of leukemia. The DNA vaccine, developed by the University of Southampton, is delivered using Inovio's proprietary electroporation technology. Financial support for the trial is being provided by the UK research charity Leukaemia and Lymphoma Research (LLR) and the Efficacy and Mechanisms Evaluation (EME) programme (which is funded by the UK Medical Research Council and managed by the UK National Institute for Health Research).