Thermogenesis requests reexamination of PharmaStem cord blood stem cell patent.

Thermogenesis Corporation (Rancho Cordova, CA) announced that it has requested that the United States Patent and Trademark Office ("PTO") reexamine patent No. 5,004,681 issued to PharmaStem Corporation. This patent relates to the collection and preservation of umbilical cord and placental blood stem cells and the use of these cells in hematopoietic or immune reconstitution.

Philip Coelho, Chairman and CEO of ThermoGenesis, said, "The organizations currently affected by this patent are our customers, not ThermoGenesis, and a ruling by the U.S. PTO could assist these stem cell banks and research organizations' abilities to conduct breakthrough research and offer life- saving treatments to patients. This request, which supports umbilical cord blood stem cell banking and assists the rapid and unencumbered proliferation of cord blood stem cell research is in concert with our urging of the FDA to license this industry and set the highest possible standards of quality. We consider these actions to be vital to a field of medicine that is still very much in its infancy but has the potential to have a significant impact on the future treatment of many lethal or debilitating diseases."

ThermoGenesis has made the request for re-examination based on our assessment that these patent claims do not distinguish over the "prior art," including the publication of several medical journal articles describing similar techniques that predated the patents. ThermoGenesis and Stitching Eurocord previously opposed PharmaStem patent claims in Europe and on April 7, 2003 the European Patent Office ("EPO") confirmed the revocation of PharmaStem's European patent on cryopreserved cord blood compositions and uses thereof by dismissing PharmaStem's appeal of an earlier ruling of the EPO, which had previously revoked all 68 claims of the European patent . The decision of the EPO is final and is not subject to appeal and applies throughout Europe.

Mr. Coelho added, "There are substantial questions as to the patentability of the claims contained in this PharmaStem patent as a result of prior art. We believe that the art of using blood stem cells to reconstitute the immune system has been in the public domain for decades. We are now respectfully requesting that the U.S. Patent and Trademark Office re-examine this patent assigned to PharmaStem."

After extensive research, Thermogenesis' newly introduced technology platforms lead the world in their ability to produce biological products from single units of blood. Umbilical cord blood banks are utilizing the Company's BioArchive(R) System as a critical enabling technology for cryogenic archiving of stem cells for transplant, while its CryoSeal(R) FS System is used to prepare hemostatic and adhesive surgical sealants from patient blood in about an hour. ThermoGenesis has been a leading supplier of state-of-the-art Ultra-Rapid Blood Plasma Freezers and Thawers to hospitals and blood banks since 1992.

ThermoGenesis Corporation

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www.thermogenesis.com