Introgen’s INGN 241 Activates Tumor Selective Cell Death Pathways in Ovarian Cancer

AUSTIN, Texas, June 8 /PRNewswire-FirstCall/ -- Researchers at Introgen Therapeutics, Inc. and The University of Texas M. D. Anderson Cancer Center have identified a novel anti-cancer activity of mda-7, the active component of INGN 241. In preclinical studies, expression of mda-7 in ovarian cancer cells potently activates a cell death (apoptosis) pathway regulated by the Fas signaling system, resulting in significant increases in apoptosis and inhibition of cancer cell proliferation. These effects were specific to cancer cells, and were not observed in normal ovarian tissue, supporting previous data showing a cancer-selective effect of INGN 241. The data are reported in the current issue of Cancer Research. Yesterday, Introgen reported that INGN 241 was found to activate additional cell death pathways in lung cancer cells. INGN 241 is currently being evaluated in Phase 2 clinical trials in patients with malignant melanoma.

“These data add to the growing body of evidence demonstrating that INGN 241 has significant activity against cancer cells but little to no effect on normal cells demonstrating its safety,” said Sunil Chada, Ph.D., Introgen’s associate vice president, Clinical Research.

Dr. Rajagopal Ramesh, assistant professor at M.D. Anderson Cancer Center and a lead author of the study said, “Of particular interest is the identification of a novel pathway through which INGN 241 works to kill ovarian cancer cells. INGN 241-mediated cell killing has multiple mechanisms of action and the outcome of our studies to date are consistent: INGN 241 activates cell death pathways and inhibits growth of cancer cells directly and through indirect mechanisms such as inhibiting new blood vessel formation. We believe these attributes increase the potential utility of this innovative investigational therapy in a variety of cancer indications.”

The studies reported today evaluated the therapeutic activity and underlying molecular mechanisms of INGN 241 in cultured ovarian cancer cells. Data from the studies show that INGN 241 inhibits cell proliferation in ovarian cancer cells by inducing cell cycle arrest and tumor cell death. These effects were not observed in normal ovarian epithelial cells. Treatment with INGN 241 appears to induce cell death through induction of the expression of several known cell death genes, including Fas, Fas Ligand, caspase-3 and caspase-9.

The mda-7 gene was discovered by the laboratory of Dr. Paul B. Fisher, professor of clinical pathology and the Michael and Stella Chernow Urological Cancer Research Scientist in the Departments of Neurological Surgery, Pathology and Urology at Columbia University. Introgen holds an exclusive worldwide license for all gene therapy applications from the Corixa Corporation.

Introgen is a leading developer of biopharmaceutical products designed to induce therapeutic protein expression using non-integrating gene agents for the treatment of cancer and other diseases. Introgen maintains integrated research, development, manufacturing, clinical and regulatory departments and operates a commercial-scale, CGMP manufacturing facility.

Introgen holds a licensing agreement with M. D. Anderson to commercialize products based on licensed technologies, and has the option to license future technologies under sponsored research agreements. Dr. Ramesh is a paid consultant to Introgen, and has sponsored research funded by Introgen. The University of Texas System Board of Regents own stock in Introgen. These arrangements are managed in accordance with M. D. Anderson’s conflict of interest policies.

Certain statements in this press release that are not strictly historical may be “forward-looking” statements, which are based on current expectations and entail various risks and uncertainties. Such forward-looking statements include, but are not limited to those relating to INGN 241 and its development as a monotherapy, as part of combination regimens, as an anti-angiogenic agent and as an immunotherapy. There can be no assurance that Introgen will be able to commercially develop gene-based drugs, that necessary regulatory approvals will be obtained or that any clinical trials or studies undertaken will be successful or that the proposed treatments will prove to be safe and/or effective. The actual results may differ from those described in this press release due to risks and uncertainties that exist in Introgen’s operations and business environment, including, but not limited to, Introgen’s stage of product development and the limited experience in the development of gene-based drugs in general, Introgen’s dependence upon proprietary technology and the current competitive environment, history of operating losses and accumulated deficits, reliance on collaborative relationships, and uncertainties related to clinical trials, the safety and efficacy of Introgen’s product candidates, the ability to obtain the appropriate regulatory approvals, Introgen’s patent protection and market acceptance, as well as other risks detailed from time to time in Introgen’s filings with the Securities and Exchange Commission including its annual report on Form 10-K filed with the Securities and Exchange Commission on March 15, 2005 and its quarterly report on Form 10-Q filed with the Securities and Exchange Commission on May 10, 2005. Introgen undertakes no obligation to publicly release the results of any revisions to any forward-looking statements that reflect events or circumstances arising after the date hereof.

Editor’s Note: For more information on Introgen Therapeutics, or for a menu of archived press releases, please visit Introgen’s Website at: http://www.introgen.com .

Contact: Introgen Therapeutics, Inc. C. Channing Burke (512) 708 9310 Ext. 322 Email: c.burke@introgen.com

Introgen Therapeutics, Inc.

CONTACT: C. Channing Burke of Introgen Therapeutics, Inc.,+1-512-708-9310, ext. 322, or c.burke@introgen.com