Tumor responses were assessed in 112 patients with recurrent head and neck cancer who received ADVEXIN. Overall, the percentages of patients with tumor responses defined by reductions in bi-dimensional tumor area on CT scan of 50 percent, 25 percent, 10 percent or stable disease for more than 2 treatment cycles were 6 percent, 7 percent, 12 percent and 22 percent, respectively. Median survival for these responder populations were 41, 17, 15 and 10 months, respectively. There was a statistically significant increase in median survival for each of the responder populations compared to the 6 month median survival of the non-responders (p less than 0.0016).
"The 41 month median duration of survival for the patients with a 50 percent or greater reduction in tumor size is very impressive and significantly greater than the six month median survival of non-responders that is typical for patients with recurrent tumors," said John Nemunaitis, M.D., Medical Director, Mary Crowley Medical Research Center. "Our findings are also consistent with a growing body of data that even smaller reductions in tumor size are clinically meaningful and are associated with increased survival."
The presentation also included data demonstrating that the predictive abnormal p53 biomarker was associated with a statistically significant increase in tumor responses to ADVEXIN therapy. A reduction in tumor size was observed in 40 percent of patients wi th the abnormal p53 biomarker compared to none (0 percent) of the patients with p53 normal tumors. In addition, tumor growth control lasting for a minimum of two treatment cycles was observed in 75 percent of patients with abnormal p53 tumors compared to 27 percent of patients with a normal p53 biomarker. Both the increased reduction in tumor size and tumor growth control associated with the abnormal p53 biomarker were statistically significant (p = 0.02). In addition, the abnormal p53 was a predictive biomarker for increased survival following ADVEXIN treatment. Median survival of patients with abnormal p53 was 11.6 months, compared with only 3.5 months for patients with normal p53 (p = 0.0007). These biomarker analyses were conducted with pre-treatment samples from 28 patients on a completely blinded basis by an independent laboratory that was not aware of the clinical results of the study. The association of tumor responses, increased survival and the abnormal p53 biomarker could not be accounted for by other known prognostic factors.
"These findings indicate important relationships between increased tumor responses and survival and the predictive abnormal p53 biomarker that is the target of ADVEXIN treatment," added Dr. Nemunaitis. "We now have the ability to match patients with a treatment that may improve their survival, and if borne out in the ongoing Phase 3 clinical trials now undergoing analyses, could fulfill the promise of molecularly targeted cancer therapies."
Biomarkers are tests or measurements that predict response to treatment. Molecular biomarkers include measurements of genetic markers or molecular pathways while clinical biomarkers refer to clinical history or clinical measurements. Introgen's molecular biomarkers include the identification of aberrant p53 function by a routine assay performed by pathology laboratories worldwide detecting abnormally elevated levels of p53 protein in tumor tissues. Introgen believes that application of molecular and clinical biomarkers can predict the patients who are most likely to respond to ADVEXIN treatment.
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. ADVEXIN has demonstrated increased survival and tumor growth control in recurrent head and neck cancer patients. ADVEXIN has demonstrated clinical activity in a number of solid tumor types in multiple phase 1, 2 and 3 clinical trials conducted worldwide.
Introgen's clinical collaborators included John Nemunaitis, M.D., Medical Director, Mary Crowley Medical Research Center, Gary Clayman, M.D., Department of Otolayngology, M.D. Anderson Cancer Center, Carol Bier-Laning, M.D., Clinical Assistant Professor, Loyola University Medical Center, Heikki Minn, M.D., Ph.D., Department of Oncology and Radiotherapy, Turku University Hospital, D. Van Echo, M.D., Director, HarborView Cancer Center, George Yoo, M.D., Vice-Chair, Department of Otolaryngology-Head and Neck Surgery and Oncology, Wayne State University, Kerstin Menander, PhD, M.D., Introgen's vice president of Clinical Development and W. Jarrard Goodwin M.D., Director, University of Miami Hospital & Sylvester Comprehensive Cancer Clinics.
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 tumor suppressor therapies to treat a wide range of cancers using tumor suppressors, cytokines and genes. Introgen maintains integrated research, development, manufacturing, clinical and regulatory departm ents 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 treatment of cancer or other diseases. 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.
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Introgen Therapeutics, Inc.
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