-Data demonstrate chemosensitization and progress toward systemic delivery-

Seattle, WA, December 9, 1999Targeted Genetics Corporation (Nasdaq: TGEN) today will present data on the Company's synthetic gene delivery technology platform at the Eighth International Conference on Gene Therapy of Cancer being held in San Diego. Dr. Pervin Anklesaria, Director of Research at Targeted Genetics, will discuss two key advances in the company's portfolio of synthetic gene delivery technologies. A presentation titled "tgDCC-E1A Therapy in Ovarian, Breast and Head and Neck Cancer" will discuss the ability of tgDCC-E1A, Targeted Genetics' lead cancer product, to sensitize tumor cells to standard chemotherapeutic agents. Additionally, Dr. Anklesaria will present data on the systemic delivery of therapeutic genes using Targeted Genetics' newest synthetic gene delivery system.

E1A Sensitizes Tumor Cells to Chemotherapy In a mouse model of human ovarian cancer expressing high levels of HER2/neu, the combination of tgDCC-E1A, paclitaxel and cisplatin provided an 80 percent decrease in tumor weight over paclitaxel/cisplatin (0.1 gram and 0.5 gram respectively, p<0.01) and a 75 percent decrease over tgDCC-E1A alone (0.1 gram and 0.4 gram respectively, p<0.01). Average tumor weight for untreated control animals was 2.4 grams. A similar model of cancer cells expressing normal levels of HER-2/neu showed that the combination of tgDCC-E1A with paclitaxel and cisplatin provided a 99 percent decrease in tumor weight over paclitaxel/cisplatin alone (0.006 gram and 0.8 gram respectively, p<0.001) and a 95 percent decrease over tgDCC-E1A alone (0.006 gram and 0.14 gram respectively, p<0.001).

"The data demonstrate that tgDCC-E1A has potent anti-tumor activity when used as a single agent and has the potential to sensitize tumor cells to standard chemotherapeutic agents," said Dr. Anklesaria. "Moreover, tgDCC-
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Contact: Page Sargisson
p.sargisson@noonanrusso.com
415-677-4455 x229
Noonan/Russo Communications
8-Dec-1999