- The Washington Times - Sunday, September 2, 2001

Someday, when a patient undergoes surgery, he or she could receive an infusion of oxygen-carrying blood substitute. The emulsion would be administered during surgery to replace the oxygen-carrying capacity of lost blood, then mixed with the patient's own blood to ensure recovery.

The hospital, meanwhile, would cut down on the number of units of donor blood used in a routine operation.

At least a half-dozen pharmaceutical companies are working on developing blood substitutes. The substitutes would be universally compatible with all blood types, free of disease and resistant to shortage.

"Our product is an oxygen-transport system," says Dr. Richard Kiral, vice president of research and development for San Diego-based Synthetic Blood International. "It does not contain the elements of blood such as clotting. The beauty of it is it acts just like hemoglobin. It takes oxygen to the lungs and offloads materials. It less than a day. I think it will have its biggest impact in short-term situations such as surgery and trauma situations."

Several other companies are testing a hemoglobin-based, rather than chemical-based, substitute blood. This product contains hemoglobin extracted from bovine red blood cells. The product is sterilized to remove possible disease. One product, manufactured by Biopure, a pharmaceutical company in Cambridge, Mass., was approved recently for use in South Africa.

Synthetic Blood International, which has spent $250 million on testing in the past decade, hopes to begin human trials within the next 18 months, Dr. Kiral says.

Another San Diego company, Alliance Pharmaceutical Corp., is developing a similar product. Alliance's Oxygent is a chemical emulsion that contains no human or animal components and has a shelf life of two years.

Oxygent, which resembles milk, has tiny particles suspended in the water-based solution. The particles are 1/40th the size of a human red blood cell and therefore are able to get around blockages that red blood cells cannot pass. Like the product made by Synthetic Blood International, the particles are made up of liquid perfluorochemicals, liquid chemicals that have a high capacity to carry oxygen.

Alliance has completed 20 human studies in eight European countries, company spokeswoman Gwen Ro-senberg says.

The Phase 3 human trial includes nearly 500 surgical patients from Europe. The use of Oxygent significantly reduced the need for donor blood, Ms. Rosenberg says. Alliance, however, had to suspend a trial using cardiac-bypass patients after some patients developed complications, including an increased incidence of stroke related to the bypass procedure used.

"For every 1,000 patients undergoing surgery, using Oxygent will be a savings of approximately 600 units of blood," Ms. Rosenberg says. "With 8 to 10 million surgeries performed worldwide, that can be really significant."

Dr. Jeanne Lumadue, medical director of Inova Blood Donor Services, says artificial blood products could help the blood supply, but only in certain situations.

"I don't think any of them are going to be entirely appropriate for our biggest blood users, which are hematology and oncology patients," Dr. Lumadue says. "It will help with surgery, because in surgery, patients lose blood quickly."

Dr. Bernadine Healy, president of the American Red Cross, which collects half of the nation's donor blood supply, says she is intrigued by the research but is skeptical that any products will be approved in the United States in the near future.

"There is no real substitute for red cells at this time," Dr. Healy says. "The one that has been approved in South Africa cannot be used repeatedly and is very expensive. With no real substitute in the near future, we still have this obligation to increase the blood supply by donating. If the perfect solution were to come along, though, we would use it."

Dr. George Nemo, head of the transfusion medicine science research group at the National Heart, Lung and Blood Institute, remains skeptical that the products will reach the point of Food and Drug Administration review.

"People have been saying artificial blood products have been coming for 10 years," he says. "I think it is still a few years away. Everything is in clinical trials, and there have been toxicity problems. Even if it does get approved, it is not going to solve a number of problems. It still can only be used in specialized situations."

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