CytoGenix Inc has received notification of the publication of international patent applications in its portfolio of antisense molecule expression technology. In addition to the parent patent of the original version of the company's proprietary TroVec ssDNA intracellular expression vector, the international patents include the latest refinement, a single plasmid system for direct enzymatic synthesis of ssDNA (EnzSyn).

The international patents were published on April 20, 2000 under the auspices of the World Intellectual Property Organization according to the Patent Cooperation Treaty (PCT), expanding the CytoGenix patent portfolio of antisense therapy enabling technology.

The first PCT publication is patent No. WO 00/22113 entitled ENZYMATIC SYNTHESIS OF ssDNA. The abstract describes the technology as: Methods and Composition for producing single-stranded cloned DNA (ss-cDNA) with a vector based system in eukaryotic cells. The vector contains all necessary signaling instructions and enzymatic functions to allow the host cell to produce the sequence of interest as ssDNA. This patent describes components included in the vector for synthesizing ssDNA in vivo. The inventors are Michael Skillern, Jonathan Elliston, Ph.D., and Charles Conrad, M.D.

The Direct Enzymatic Synthesis method (EnzSyn) is the latest refinement of the company's ssDNA intracellular expression technology. As the list of antisense molecules continues to grow and more disease states are targeted, the need for dependable delivery and expression systems increases accordingly.

The second PCT publication is WO 00/22114 entitled PRODUCTION OF ssDNA IN VIVO. This patent covers the original two-plasmid ssDNA intracellular expression technology (TroVec) previously protected by the US Patent 6,054,299 issued on April 25, 2000. The inventor is Charles Conrad, M.D. The abstract describes the technology as: Methods and compositions for producing single-stranded cloned DNA in eukaryotic cells, specifically a DNA cassette that produces ss-cDNA in vivo by taking advantage of the ``stem loop-structure.''

The TroVec technology was provided to several universities at cost for Beta Testing. The informal comments the company has received from the researchers have been uniformly positive. One of the university research scientists commented that he achieved over 100 times the expression of the selected oligonucleotide sequence using the vector than with traditional methods. No formal reports will be available until the results of the research are the subject of published peer review studies.

The direct enzymatic synthesis vector (EnzSyn), a single plasmid system which has demonstrated superior expression in the company's laboratory, is being used in new studies in progress under sponsored research agreements with Baylor College of Medicine, Texas Medical Center in Houston. The EnzSyn vector is also available now to the existing Beta Test sites for continuing evaluation.