X-Message-Number: 13612 Date: Fri, 21 Apr 2000 09:57:31 -0400 From: "J. Hughes" <> Subject: Blood Substitute and Freezing Experiment Ice-Cold Blood-Substituted Dogs and Hamsters Revived After Prolonged Periods of Clinical Death; Results May Hold Clues to Protecting the Brain Updated 12:23 PM ET April 17, 2000 Current quotes (delayed 20 mins.) BTX 9 1/4 0 (0.00%) BERKELEY, Calif. (BW HealthWire) - BioTime, Inc. (AMEX:BTX) announced today that a team of its research scientists directed by Dr. Hal Sternberg, BioTime research vice president, revived five hamsters following extended periods of cardiac and circulatory arrest. The results will be reported at Fluid Resuscitation 2000, a conference to be held on May 31-June 2, 2000 in Galveston, Texas, by BioTime scientist Cornelia Gramlich. The hamsters were anesthetized, chilled and completely blood substituted with modified forms of Hextend, BioTime's proprietary physiologically balanced plasma volume expander currently used in the US to treat blood volume loss during surgery. They were then further cooled to near-freezing, their hearts were arrested and they were maintained without heartbeat or circulation for 4-5 hours. The animals were then warmed, transfused and revived to consciousness. Previous experiments conducted by Dr. Sternberg indicated anecdotally that hamsters could be revived after 4-6 hours of hypothermic blood substitution and cardiac and circulatory arrest. However, the latest work used a patentable combination of BioTime's proprietary devices, solutions and protocols to allow a more consistent and repeatable result. An important factor in obtaining these results involved lowering CO2 levels in the blood, and presumably also in the brain, before deep chilling and the induction of circulatory arrest. Using a related approach, BioTime scientists and their collaborators have been able to fully revive dogs blood-substituted with a modified Hextend solution and chilled to near-freezing. In a series of experiments to be reported on at a scientific conference this week, five out of six dogs reviving after 2 hours of hypothermic circulatory arrest are currently alive and well. As in the hamster experiments, low blood levels of CO2 prior to cooling were also associated with good outcomes. Dr. George V. Letsou of the Department of Surgery, University of Texas Health Science Center, Houston, TX, will present the work on Tuesday, April 18, 2000, at a session of Experimental Biology 2000, a scientific convention taking place this week in San Diego, California. "BioTime's unique devices, solutions and techniques have allowed us to gain a basic understanding of some of the important factors in maintaining subjects at low temperatures for extended time periods," said Dr. Sternberg. "This understanding is critical in designing technology to allow prolonged surgeries on the heart and brain in which circulation is interrupted, to facilitate rescue in severe trauma situations, and to prolong the period that organs can be stored prior to transplantation." "In addition, understanding the mechanism of delaying brain death at low temperatures will facilitate an understanding of how to best treat the lack of blood flow to the brain that can occur at normal temperatures during heart disease and trauma, brain pathology resulting from suffocation, drowning, stroke and other causes." BioTime is in the process of finalizing an amendment to its IND for Hextend, in order to study the use of this plasma expander in low temperature medicine. BioTime, headquartered in Berkeley, California, is engaged in the research and development of blood plasma volume expanders, blood replacement solutions during hypothermic (low temperature) surgery, organ preservation solutions and technology for use in surgery, emergency trauma treatment, the preservation of organs awaiting transplant, and other applications. Information about BioTime can be found on the web at www.biotimeinc.com. The matters discussed in this press release include forward-looking statements which are subject to various risks, uncertainties and other factors that could cause actual results to differ materially from the results anticipated. Such risks and uncertainties include but are not limited to the results of clinical trials of BioTime products; BioTime's ability to obtain FDA and foreign regulatory approval to market its products; competition from products manufactured and sold or being developed by other companies; the price of and demand for BioTime's products; BioTime's ability to negotiate favorable licensing or other manufacturing and marketing agreements for its products; the availability of ingredients used in BioTime products; and the availability of reimbursement for the cost of BioTime products (and related treatment) from government health administration authorities, private health coverage insurers and other organizations. These and other risk factors are discussed in BioTime's Annual Report on Form 10-K filed with the Securities and Exchange Commission. Contact: BioTime, Inc. Victoria Bellport, 510/845-9535 Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=13612