Introgen Therapeutics, Inc. reported updated data from several clinical studies which demonstrate the activity of Advexin p53 therapy in patients with cancers of the head and neck, lung, breast and esophagus. Additional results showing utility of Advexin in the inherited cancer known as Li-Fraumeni Syndrome were also reported. Evaluation of molecular and clinical biomarkers was able to predict patient populations most likely to benefit from Advexin therapy.
Data were presented over the weekend at the annual meeting of the International Society for Cell and Gene Therapy in Chiba City, Japan by Sunil Chada, Ph.D., Introgen's associate vice president of Clinical Research and Development. The international meeting joined hundreds of clinicians and researchers to discuss the progress of novel cancer treatments.
Dr Chada commented, "Advexin shrinks tumours, halts tumour growth, and improves symptoms in patients with multiple types of cancer. Patients with tumours having abnormal p53 were shown to have improved outcomes following Advexin therapy. These observations are consistent with the presence of p53 abnormalities in the majority of cancers. Aberrant p53 is the molecular target of Advexin therapy."
Dr. Robert E. Sobol, Introgen's senior vice-president of Medical and Scientific Affairs, stated, "We have advanced our analyses of Advexin efficacy in recurrent, squamous cell carcinoma of the head and neck. These patients have limited effective treatment options. The Advexin tumour response rate defined by a 30 per cent reduction in tumour size was 10.3 per cent for the overall population and 26.5 per cent for the clinical biomarker defined population with a progression free interval of greater than 12 months from initial treatment who had prior chemotherapy. The durations of these responses were durable with a median of 5.7 months. In the overall treatment population, tumour response was associated with a statistically significant increase in survival. The median survival of the responders was 16.9 months compared to 5.4 months for non-responders (p < 0.0001). This phase 2 study evaluated 106 patients utilizing the Advexin dose employed in our phase 3 clinical trials."
Introgen previously reported the identification of a set of prognostic indicators associated with high response rates and increased survival in Phase 2 clinical trials of Advexin therapy in patients suffering from head and neck cancer. Biomarkers are tests or measurements that can predict response to treatments targeted for particular individuals. Molecular biomarkers include measurements of genetic markers or molecular pathways while clinical biomarkers refer to clinical history or clinical measurements. Application of these biomarkers can predict the patients who are most likely to respond to Advexin treatment and those patients most likely to be unresponsive to conventional treatments. Based upon Introgen's findings and phase 2 clinical trials, patients with abnormally high p53 protein expression levels are most likely to benefit from Advexin p53 therapy, but have poor prognoses with conventional therapies.
In August, Introgen announced that an agreement had been reached with the US Food and Drug Administration (FDA) to utilize biomarker data in the evaluation of phase 2 and phase 3 clinical trials. The Company is now amending its phase 3 clinical trial analyses plan to include analysis of molecular and clinical biomarkers. Introgen is seeking approval for advanced, recurrent squamous cell carcinoma of the head and neck in the US Introgen plans to initiate interim efficacy analyses of its Advexin phase 3 clinical trials within the next quarter, and report the results to FDA later in 2007. Introgen expects head and neck cancer regulatory filings in the US and EU to be completed within 2007.
Advexin 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 durable locoregional disease control in recurrent head and neck cancer patients. Prognostic biomarkers can identify patients most likely to respond to Advexin. Advexin has demonstrated clinical activity in a number of solid tumour types in multiple phase 1, 2 and 3 clinical trials conducted worldwide. A request for accelerated approval for Advexin is now pending at the US Food and Drug Administration (FDA). The FDA has selected Advexin as a fast track program for an unmet medical need and has designated Advexin for orphan drug use for recurrent head and neck cancer. Through its European subsidiary, Gendux, Advexin has received Orphan Medicinal Product Designation by the European Medicines Agency for Li-Fraumeni Syndrome.