Release issued 13th May 2002

CLEVELAND, Athersys Inc. today announced the completion of a $16.2 million private placement of common stock. The financing includes investments from both existing and new shareholders. New institutional investors include National City Equity Partners, Greenleaf Capital Management and the Biomedical Sciences Investment Fund of the Singapore Economic Development Board. The proceeds of the financing will be used to support Athersys' ongoing research and product development programs in areas including oncology, inflammation, neurobiology and developmental biology.

"The completion of this financing further validates the strength and promise of our technologies and our strategy for building a fully integrated biopharmaceutical company," commented Gil Van Bokkelen, Ph.D., chairman, president and chief executive officer of Athersys. "To complete this financing in a difficult capital market environment is a testament to the value created by our core technologies and the continued development of our drug discovery pipeline. The additional capital will serve as an invaluable resource as Athersys continues to drive its product development programs toward the clinic and the marketplace."

To date, Athersys has raised approximately $100 million in capital and has created strategic partnerships with leading pharmaceutical companies, biotechnology companies and academic institutions including Pfizer, Bristol-Myers Squibb, Medarex, 3-Dimensional Pharmaceuticals and the Cleveland Clinic Foundation.

Athersys is a functional genomics and biopharmaceutical company engaged in the development, application and commercialization of therapeutic products and novel gene expression tools. The company's research and development programs are focused on its two proprietary platform technologies: RAGE (Random Activation of Gene Expression) and SMC(tm) (Synthetic Microchromosome(tm)) vector system. RAGE is a novel gene expression system that provides the unique ability to produce protein from virtually every gene in the human genome, without requiring the cloning of individual genes or use of cDNA libraries. RAGE greatly accelerates the identification and validation of novel drug targets by enabling the direct correlation of a disease process or characteristic with expression of a specific protein. As a result, RAGE has powerful applications in functional genomics; the generation of validated drug targets; discovery of novel antibody drug targets; structural proteomics and rational drug design; and the production of protein therapeutics. Athersys is developing novel therapeutic products based on its proprietary technologies, through partnerships and internal research and development programs. This press release and further information on Athersys, Inc. can be found on the World Wide Web at: www.athersys.com.

Statements herein that are not descriptions of historical facts are forward-looking and subject to risk and uncertainties. Actual results could differ materially from those currently anticipated due to a number of factors, including risks relating to the early stage of products under development; uncertainties related to patent protection; uncertainties relating to clinical trials; dependence on third parties, including strategic partners, collaborators and key personnel; and risks relating to the development and commercialization, if any, of Athersys' proposed products (such as effectiveness of our products, marketing, manufacturing, safety, regulatory, patent or product liability, supply, competition and other risks).

Contacts:

Jeff SteinhilberChief Financial Officer Athersys, Inc. (216) 431-9900 ext. 250 ir@athersys.com

Michael Lawson Feinstein Kean Healthcare For Athersys, Inc.(617) 577-8110 mlawson@fkhealth.com

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(13th May 2002) ATHERSYS INC. NAMED TO THE RED HERRING 100

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