Geron Reports Issuance of U.S. Patent for Human Telomerase Gene.

Business Editors/Health & Medical Writers

MENLO PARK, Calif--(BW HealthWire)--July 17, 2001

Geron Corporation (Nasdaq:GERN) announced today that the U.S. Patent Office has issued U.S. Patent No. 6,261,836 with claims directed to the gene that encodes human telomerase. As reported in Geron Corporation's Form 10-K, the U.S. Patent and Trademark Office had previously suspended examination of the application that gave rise to this patent pending possible declaration of an interference. That suspension was lifted prior to the issuance of the patent.

Telomerase is an enzyme that can extend the lifespan of normal cells. This feature has potential utility in numerous gene and cell therapies. It is also an excellent target for anti-cancer therapeutics since inhibiting telomerase can result in targeted cancer cell death. The telomerase enzyme has two essential components, an RNA component and a protein component.

"Geron already owns issued patents on the cloned RNA component of human telomerase," said David J. Earp, J.D., Ph.D., Geron's vice president of intellectual property, "and we are pleased today to announce the issuance of our U.S. patent with claims covering the cloned gene that encodes the human telomerase protein component. Corresponding patents for the cloned protein component have already issued in the U.K. and Switzerland, and we have applications pending in all major jurisdictions worldwide."

Geron scientists worked around the clock in an intensive effort to be the first to clone the human telomerase gene. "The outstanding effort of that team, led by our chief scientific officer Calvin Harley, Ph.D., resulted in the successful isolation of the human telomerase gene, which we are using in a number of our product development programs, including those in oncology and regenerative medicine," noted Thomas B. Okarma, Ph.D., M.D., Geron's president and chief executive officer.

Geron is developing oncology applications based on telomerase through four different means. First, the company is identifying and developing compounds that inhibit telomerase to induce cancer cell death. Second, the use of the telomerase gene promoter (also cloned by Geron) is being investigated for use in viruses which selectively replicate in, and kill, cancer cells. Third, Geron is developing telomerase as an antigen for use in anti-cancer immunotherapies. Finally, the company is developing screening methods that utilize telomerase as a marker for early warnings of new or recurrent cancers.

Geron's regenerative medicine group is developing telomerase-based gene therapies to address conditions associated with cell aging, such as various forms of chronic liver disease and skin wounds.

Further, telomerase may also be used to confer extended replicative capacity to cells that Geron intends to manufacture from human embryonic stem cells, such as cardiomyocytes to treat heart disease, neural cells to treat spinal cord injury and brain diseases, and hepatocytes to treat liver failure.

Geron has promoted research into the biology of telomerase and telomeres by distributing the cloned human telomerase gene to more than 500 laboratories around the world, and will continue to do so following issuance of this patent.

Geron is a biopharmaceutical company focused on developing and commercializing therapeutic and diagnostic products for applications in oncology and regenerative medicine, and research tools for drug discovery. Geron's product development programs are based upon three patented core technologies: telomerase, human embryonic stem cells and nuclear transfer.

This news release may contain forward-looking statements made pursuant to the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995. Investors are cautioned that such forward-looking statements in this press release regarding product development and future applications of Geron's technology constitute forward-looking statements involve risks and uncertainties, including, without limitation, risks inherent in the development and commercialization of potential products, dependence upon collaborative partners and the maintenance of our intellectual property rights. Actual results may differ materially from the results anticipated in these forward-looking statements. Additional information on potential factors that could affect our results and other risks and uncertainties are detailed from time to time in Geron's periodic reports, including the quarterly report on Form 10-Q for the quarter ended March 31, 2001.

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