Vion Demonstrates Readiness Of First Tumor-Targeting Salmonella For Human Testing Against So...( Stability Safety and Efficacy Demo...)

Stability, Safety and Efficacy Demonstrated for Novel Bacterial Anticancer Agent

NEW HAVEN, CT (April 12, 1999): Research by scientists at Vion Pharmaceuticals (Nasdaq: VION) and their Yale University collaborators demonstrates the suitability of the company's lead TAPETR vector, VNP20009, to enter human clinical testing. At the annual meeting of the American Association of Cancer Research (AACR) Vion scientists presented data demonstrating the genetically engineered Salmonella bacteria's overall safety profile and tumor targeting ability, including TAPET's safety when administered to non-human primates. In addition, they reported the ability of unarmed TAPET organisms (without "warheads") to inhibit both primary and metastatic tumors by more than 90% and to prolong survival in mouse xenograft models (human tumor tissue transplanted into mice) of several human cancers. In March, Vion announced that the company had filed an Investigational New Drug (IND) application to begin human safety testing with TAPET in the United States later this year. The U.S. filing is in addition to regulatory filings made by Vion in support of clinical trials of TAPET in Europe. Vion is developing TAPET organisms as vectors for the targeted, systemic delivery of anticancer agents to tumors throughout the body.

David Bermudes, Ph.D., associate director of biology at Vion, said, "VNP20009 possesses all of the properties required for its safe use in humans. These include attenuated virulence, a reduction in the potential of the bacterium to elicit septic shock, genetic stability in its safety-related mutations, and sensitivity to conventional antibiotics. At the same time, VNP20009 maintains TAPET's desirable anti-tumor properties, including the ability to selectively amplify in tumors at levels of at least 500:1 compared with normal tissues and to suppress tumor growth by more than 90%. Moreover, the VNP20009 TAPET strain is easily amenable
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Contact: Joan Kureczka
jkureczka@aol.com
415-821-2413
Kureczka/Martin Associates
11-Apr-1999