Vical Incorporated announced the issuance of a key European Patent, EP1032428, entitled, "Treatment of Cancer Using Cytokine-Expressing Polynucleotides and Compositions Therefor." The company also announced the recent issuances of three additional European patents: EP0795015, "Plasmids Suitable for IL-2 Expression," EP0742820, "Production of Pharmaceutical-Grade Plasmid DNA," and EP0802975, "Process for Reducing RNA Concentration in a Mixture of Biological Material Using Diatomaceous Earth."

The new '428 patent broadly claims gene-based, extra-tumoral delivery of any cytokines for the treatment of cancer. Delivery can be either free from or formulated with transfection-facilitating materials such as cationic lipids or polymers. Cytokines are proteins such as interleukins and interferons which regulate specific cell functions, and typically are used to stimulate an immune response against cancer cells.

The new '015 patent specifically claims the composition, manufacture and application of gene-based cancer treatments delivering the cytokine interleukin-2 (IL-2). The '820 and '975 patents claim specific processes developed by Vical for the manufacture and purification of DNA.

"We are pleased to continue expanding our patent coverage in Europe to supplement our coverage in the United States," said Vijay B. Samant, Vical's President and Chief Executive Officer. "Our intellectual property supports a broad range of applications for our platform technology, both for our own in-house development programs and those of our licensees."