Generex Biotechnology Corporation (www.generex.com) (OTC Bulletin Board: GNBT), together with its wholly-owned immunotherapeutic vaccines subsidiary, Antigen Express, Inc. (www.antigenexpress.com), and RXi Pharmaceuticals Corporation (www.rxipharma.com) (NasdaqCM: RXII), a recognized leader in RNAi-based therapeutics, today announced that they have obtained positive early research data from their collaboration to explore the use of RXi's RNAi technology to develop proprietary vaccine formulations for active immunotherapy.
Initial results from the collaboration demonstrated success in using RXi's proprietary self-delivering rxRNA™ (sd-rxRNA™) compounds to silence genes up to 80% in hemopoietic cells. The ability to knock down expression of certain genes in isolated hemopoietic-derived cancer cells (ex vivo) has the potential to convert them into specific immune-stimulants and opens the possibility for development of a new class of anticancer therapeutic vaccines. RXi's sd-rxRNA compounds may be particularly suitable for this use, since they are able to cross cell membranes without the assistance of any delivery agent.
"We are very pleased to have identified a technology that enables efficient RNAi silencing in hemopoietic cells," said Dr. Eric von Hofe, President of Antigen Express. "These types of cells are notoriously difficult to deliver RNAi and other oligonucleotide molecules to. In contrast to other gene silencing technologies, RXi's compounds act more like small molecules, which may greatly facilitate clinical development."
Antigen Express is developing proprietary vaccine formulations for active immunotherapy and has previously employed a DNA vector approach for silencing expression of the MHC class II-associated invariant chain (Ii protein) in patients with acute myelogenous leukemia. This strategy has been shown to transform cancer cells into specific and potent immunotherapeutic agents to combat cancer in a variety of pre-clinical models. In addition to hematological malignancies, this strategy is applicable to different types of solid tumors as well, such as colon cancer.
"We are pleased to have generated early compelling data in collaboration with Antigen Express for active immunotherapy with potential oncology applications," said Dmitry Samarsky, Ph.D., Vice President of Technology Development at RXi. "Our rxRNA™ therapeutic platform may have exciting applications in the development of therapeutic vaccines, and we look forward to the potential for expanding and further developing this opportunity based on our combined approaches."
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