BLUE BELL, Pa., July 24, 2013 /PRNewswire/ -- Inovio Pharmaceuticals, Inc. (NYSE MKT: INO) announced today that in a preclinical study with two animal models, Inovio's hTERT (human telomerase reverse transcriptase) DNA cancer vaccine administered with Inovio's CELLECTRA ® adaptive electroporation delivery technology generated robust and broad immune responses, broke the immune system's tolerance to its self-antigens, induced T-cells with a tumor-killing function, and increased the rate of survival. Because high levels of hTERT expression are found in 85% of human cancers, regardless of type, Inovio's cancer candidate holds the potential to perform as a "universal" cancer therapeutic based on these early but unprecedented results. Following this strong preclinical data, Inovio plans to advance its synthetic hTERT cancer vaccine, INO-1400, into clinical trials in 2014.
These results appear in the American Association for Cancer Research journal, Cancer Immunology Research , in a paper entitled: "Highly optimized DNA vaccine targeting human telomerase reverse transcriptase stimulates potent antitumor immunity," authored by Inovio researchers and collaborators.
Dr. J. Joseph Kim, Inovio's president and CEO, said: "Inovio has demonstrated in multiple published human studies that our synthetically optimized DNA vaccines delivered with our CELLECTRA delivery system generate best-in-class T-cell immune responses. Here we show that in monkeys our hTERT DNA cancer vaccine generated T-cell immune responses more than 18-fold higher than the previous best results of a peer's hTERT therapeutic vaccine, which was also a DNA vaccine delivered with electroporation. We are particularly enthusiastic about our vaccine's potential use as a "universal" cancer therapeutic, given that hTERT is present in the vast majority of cancer types yet rare in normal cells. We plan to develop INO-1400 to treat breast and lung cancers and then expand to other cancer types. This hTERT therapy adds to a growing Inovio oncology franchise spearheaded by our phase II candidate, VGX-3100 for treating HPV-related pre-cancers and cancers, as well as our near clinical INO-5150 to treat prostate cancer."
Data from both murine and human systems over the past 10 years have demonstrated that TERT-specific cytotoxic T-lymphocytes (CTLs) can recognize and kill TERT-expressing tumor cells in multiple types of cancers. In fact, previous research has shown that breast cancer patients who mounted an hTERT-specific CTL response exhibited significantly longer rates of survival. However, the immune system's tolerance of cancer cells and their associated antigens produced in the body, which exists to prevent autoimmune diseases, often restricts the immune system's antitumor response. A major challenge for cancer vaccine development has been to develop approaches to break this tolerance in tumor-bearing hosts. Recent advances in our understanding of antigen presentation and tolerance have led Inovio to create this synthetic DNA vaccine targeting the hTERT antigen.