Introgen's Novel p53 Cancer Vaccine - SCLC

[tnmynatt]

Introgen's Novel p53 Cancer Vaccine Sensitizes Tumors to Platinum and Taxane Chemotherapies

http://www.corporate-ir.net/ireye/ir_si ... _id=710097

Promising Interim Data from Phase 2 Clinical Trial in Advanced Small Cell Lung Cancer Presented at ASCO

ORLANDO, Fla., May 16 /PRNewswire-FirstCall/ -- Introgen Therapeutics, Inc. (Nasdaq: INGN) today reported interim results of its Phase 2 trial of INGN 225, its investigational cancer vaccine, in patients with advanced small cell lung cancer (SCLC) previously treated with chemotherapy. Following INGN 225 treatment, 67 percent of the evaluable patients in the study had objective responses (greater than 50 percent tumor reduction) to subsequent chemotherapy. The data were presented yesterday (Abstract #2543) at the 41st Annual Meeting of the American Society of Clinical Oncology (ASCO) in Orlando. Researchers at the H. Lee Moffitt Cancer Center are conducting the study in collaboration with Introgen.

"These results are very encouraging given the surprisingly substantial proportion of patients who responded to second-line chemotherapy following treatment with INGN 225," said Scott Antonia, M.D., Ph.D., associate professor in the Interdisciplinary Oncology Program at the H. Lee Moffitt Cancer Center and the leading clinical investigator in the study. "This high rate of response is not typically seen in this patient population, and the results observed so far suggest that INGN 225 may sensitize cancer cells to the effects of chemotherapy. This is a promising finding and suggests that INGN 225 may have important utility in the future treatment of small cell lung cancer."

INGN 225 is a therapeutic vaccine consisting of a cancer patient's dendritic cells, a type of immune cell, treated with an adenovector carrying the human p53 gene (Ad-p53). The abstract described results from patients with advanced SCLC. Eight weeks following the last dose of first line chemotherapy, dendritic cells were collected from each patient and treated in the laboratory with Ad-p53, to generate the INGN 225 vaccine. Initial results show that the vaccine was well tolerated, with no appreciable INGN 225 related toxicity in any of the treated patients.

After vaccine therapy, eighteen patients with progressive disease were treated with second-line chemotherapy. To date, 12 patients (66.7 percent) had objective responses or tumor reduction greater than 50%. Historically the expected objective response rate in these patients is between 20 and 30 percent. There was a statistically significant correlation between the development of a p53 immunological response to vaccination and objective responses to second line chemotherapy (p = 0.032).

"The expression of p53 is tightly regulated in normal cells, but becomes abnormally over expressed in a large number of cancers," said Dmitry Gabrilovich, M.D., Ph.D., associate professor of Oncology at the H. Lee Moffitt Cancer Center and principal investigator of the study. "The accumulation of high levels of p53 protein in cancer cells relative to normal cells makes the protein an excellent target for a cancer-specific immunotherapy. We are evaluating the mechanism by which INGN 225 appears to sensitize cancer cells to the effects of chemotherapy, which is an exciting finding that may help to further our understanding how p53-based cancer therapies may be used in clinical practice."

Robert E. Sobol, M.D., Introgen's senior vice president of Scientific and Medical Affairs said, "Our data in lung cancer patients indicate that INGN 225 may sensitize tumors to the effects of platinum and taxane chemotherapies. Of particular interest, patients with highly aggressive disease (termed Platinum resistant) showed improved response rates and increased survival compared to historical controls. Some patients refractory to chemotherapy became responsive to chemotherapy re-treatment after receiving INGN 225 vaccine. These findings are consistent with the results observed in lung and breast cancer patients with another of our p53 targeted therapies, ADVEXIN, that increased the expected effects of cisplatin, taxane and doxorubicin chemotherapies. As platinum, taxanes and doxorubicin are among the most common types of cancer chemotherapies, these findings have important future implications for improving the efficacy of these widely utilized cancer treatments."

INGN 225 is also being evaluated in a Phase 1/2 trial in patients with breast cancer. Introgen is also developing the Ad-p53 formulation, ADVEXIN®, for the treatment of a variety of cancers.

[dadstimeon]

Very interesting Tina. Thanks for sharing. Rich