Introgen's ADVEXIN Demonstrates Clinical Benefit in Inherited Cancer

Introgen Therapeutics, Inc. (NASDAQ:INGN) announced today the publication of data describing the dramatic clinical benefit of its lead product ADVEXIN in a patient with a rare inherited form of cancer known as Li-Fraumeni Syndrome (LFS), a genetic disorder characterized by inherited mutations in the p53 tumor suppressor gene. This is the first reported treatment of Li-Fraumeni tumors with a therapy targeted to the underlying molecular cause of the disorder. These cancers are due to inherited abnormalities of p53 function which is directly addressed by ADVEXIN treatment. In addition, the results of the study evaluated biomarkers which confirmed the molecular mechanism of activity of ADVEXIN. These biomarkers will guide ADVEXIN therapy of other cancers with p53 abnormalities, which is one of the most common molecular defects found in virtually all types of cancer. The patient was treated as part of a study at the Mary Crowley Medical Research Center in Dallas, TX and the importance of the findings were underscored by publication this week in the Spotlight on Clinical Response editorial highlights section of the current issue of Molecular Cancer Therapeutics, a journal of the American Association for Cancer Research. ADVEXIN treatment of a tumor in an LFS patient led to improvement of tumor-related symptoms and resulted in a complete response as determined by positron emission tomography (PET) scans. In addition, molecular biomarker studies using tumor biopsies before treatment detected abnormal levels of p53 protein predictive of ADVEXIN efficacy. Tumor biopsies analyzed after therapy identified restoration of p53 tumor suppressor function including suppression of tumor growth and induction of tumor cell death validating ADVEXIN’s mechanisms of action. "This case study showcases and provides proof of the principle for the therapeutic application of targeted ADVEXIN therapy in tumors with p53 abnormalities that are among the most common and fundamental molecular defects in cancer," said Neil Senzer, M.D., Scientific Director, Mary Crowley Medical Research Center, and lead author of the article. "ADVEXIN's mechanism of action is targeted to restoring p53 tumor suppressor function that is abnormal in Li-Fraumeni tumors and in many other types of cancer.” ADVEXIN is being developed for European markets by Gendux AB, a subsidiary of Introgen Therapeutics, Inc. The European Medicines Agency (EMEA) has designated, and the European Union has confirmed, ADVEXIN p53 therapy as an Orphan Drug for the treatment of LFS. A Letter of Intent to the EMEA regarding Marketing Authorization Application for the approval of ADVEXIN to treat LFS was filed under the Exceptional Circumstances Approval procedures in the EU. Collaborators on this publication included clinicians from Mary Crowley Medical Research Center, Sammons Cancer Center, Baylor University Medical Center, The Royal Marsden Hospital NHS Foundation Trust, Imperial College London Hammersmith Campus, and the Institute of Cancer Research in the United Kingdom. About Li-Fraumeni Syndrome Approximately 400 families are affected by LFS annually. The majority of LFS families contain mutations in the p53 tumor suppressor gene. Affected individuals often develop multiple primary tumors, which typically occur at a young age. Conventional therapy of patients with the Li-Fraumeni Syndrome is frequently unsuccessful due to the occurrence of multiple malignancies that share a common p53 genetic defect fundamental to cancer progression and the development of treatment resistance. Defects in p53-mediated cell death pathways cause these tumors to develop resistance to standard therapy, resulting in early death. Additionally, because affected individuals lack p53-mediated DNA repair function, treatment with DNA damaging agents such as radiation and some types of chemotherapy can induce genetic changes that give rise to additional tumors. About ADVEXIN ADVEXIN p53 therapy is a targeted molecular therapy with broad applicability in a wide range of tumor types and clinical settings because it targets one of the most fundamental and common molecular defects, abnormal p53 tumor suppressor function, associated with cancer initiation, progression and treatment resistance. Prognostic biomarkers can identify patients most likely to respond to ADVEXIN. ADVEXIN has demonstrated clinical activity in a number of solid tumor types in multiple phase 1, 2 and 3 clinical trials conducted worldwide. About Introgen Therapeutics, Inc. Introgen Therapeutics, Inc. is a biopharmaceutical company focused on the discovery, development and commercialization of targeted molecular therapies for the treatment of cancer and other diseases. Introgen is developing molecular therapeutics, immunotherapies, vaccines and nano-particle therapies to treat a wide range of cancers using tumor suppressors and cytokines. Introgen maintains integrated research, development, manufacturing, clinical and regulatory departments and operates multiple manufacturing facilities including a commercial scale cGMP manufacturing facility. Statements in this release that are not strictly historical may be "forward-looking" statements, including those relating to Introgen's future success with its ADVEXIN clinical development program for the treatment of patients with Li-Fraumeni Syndrome. The actual results may differ from those described in this release due to risks and uncertainties that exist in Introgen's operations and business environment, including Introgen's stage of product development and the limited experience in the development of gene-based drugs in general, 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 filings on Form 10-K and Form 10-Q. 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: www.introgen.com.