Introgen Therapeutics, Inc., a developer of targeted molecular therapies for cancer, reported additional efficacy data from the company's recent regulatory filings seeking approval of Advexin (p53 tumour suppressor therapy) in the United States and Europe.

These findings resulted from supportive statistical analyses based on data from the pivotal phase 3 clinical trial of Advexin in patients with recurrent, refractory head and neck cancer. These analyses (Cox Regression) evaluated the length of survival of patients in the biomarker population receiving Advexin as compared to patients in the biomarker population receiving methotrexate.

Results showed that patients with p53 tumour profiles positive for Advexin efficacy demonstrated statistically significant increased survival benefit at both six months (p less than 0.0051) and overall (p = 0.0265) following treatment with Advexin. Additionally, these analyses showed that for patients with tumour p53 profiles negative for Advexin efficacy, there is a statistically significant increased survival benefit associated with methotrexate treatment. These data were presented at the American Association for Cancer Research (AACR) Centennial Conference on Translational Cancer Medicine 2008: Cancer Clinical Trials and Personalized Medicine.

In conjunction with previously reported findings, Introgen believes these latest results extend and confirm that Advexin, as compared to methotrexate, achieved statistically significant benefits in tumour response rate, six-month survival, and overall survival in the study's prospectively defined p53 biomarker patient population. Accordingly, Advexin successfully achieved both the study's primary and secondary efficacy endpoints in the biomarker patient population which were prospectively designated with the United States Food and Drug Administration (FDA). The primary efficacy endpoint of the Phase 3 study was survival in either the intent-to-treat (ITT) or biomarker patient population. The secondary efficacy endpoint was tumour response in either the ITT or biomarker patient population.

"These findings corroborate and further strengthen previously announced results of our phase 3 study which demonstrated Advexin's positive impact on survival in patients with biomarker profiles positive for efficacy," said Robert E. Sobol, M.D., senior vice president, Medical and Scientific Affairs at Introgen. "We look forward to working with the FDA and European Medicines Evaluation Agency in connection with the approval process of Advexin for patients with recurrent, refractory head and neck cancer."

The results of the statistical analyses presented at the AACR conference are included in the Advexin Biologics License Application (BLA) to the FDA and the Advexin Marketing Authorization Application (MAA) to the European Medicines Evaluation Agency (EMEA).

"These analyses were conducted as part of Introgen's recent regulatory approval application submission processes in the US and Europe and add to the previously reported findings of Advexin efficacy," stated Max Talbot, Ph.D., Introgen's senior vice president, Worldwide Commercial Development. "We will continue to identify and utilize relevant opportunities, including medical journals and scientific conferences, to publish and present more detailed findings from our regulatory submissions."

Advexin p53 therapy is a targeted molecular therapy with broad applicability in a wide range of tumour types and clinical settings because it targets one of the most fundamental and common molecular defects, abnormal p53 tumour suppressor function, associated with cancer initiation, progression and treatment resistance. Advexin has demonstrated increased survival and tumour growth control in recurrent head and neck cancer patients. Advexin has demonstrated clinical activity in a number of solid tumour types in multiple phase 1, 2 and 3 clinical trials conducted worldwide. Advexin is considered an 'Orphan Drug' in the US for the treatment of recurrent, refractory head and neck cancer, which, if approved, entitles the drug to extended market exclusivity for the approved indication. Advexin is a registered trademark describing p53 therapy, developed by Introgen under exclusive worldwide licenses from The University of Texas M.D. Anderson Cancer Center.