The Race For A Blood Substitute

January 20, 1992|By Michael Pollick

Imagine if there were a good substitute for human blood -- something that would carry life-giving oxygen through the body.

An ambulance crew could administer it in emergencies -- something that cannot be done now because the patient's blood must first be typed and cross-matched.

A surgery candidate could avoid the ever-present risk of catching acquired immune deficiency syndrome or hepatitis through a blood transfusion.

Imagine the benefits for society -- and the profits for the manufacturer and its shareholders.

The race to develop a safe substitute for blood has become one of the hottest medical contests of the '90s. Competitors range from giants like New York Stock Exchange-listed Baxter Internationalto tiny Owings Mills-based Burns Laboratories Inc.

In between are a couple of companies that recently raised millions of dollars through initial public stock sales, based on widely different technologies for making the key ingredient of blood: hemoglobin.

At stake is a market measured in the billions of dollars.

"It's a big market even for Baxter International," says Dr. Thomas A. Schmitz, general manager of the blood substitutes program for Baxter, which has annual sales of $7 billion.

While the approaches vary widely, all the companies are focused on the same goal: transferring oxygen from the lungs to the tissues and removing carbon dioxide from the body.

There are many other important elements in blood, but it is the highly complex hemoglobin protein that accomplishes this life-sustaining mission.

Here's the problem: Outside the protective environment of the red blood cell, hemoglobin doesn't last long. In fact, it splits up into molecular halves that are toxic to the kidneys.

Inside the red blood cell, there is a naturally occurring chemical that loosely holds the two molecular halves together in exactly the right shape to allow oxygen and carbon dioxide to easily attach and then detach.

But if you try to sterilize blood cells by heat treatment, to get rid of viruses such as HIV (the virus that causes AIDS) or hepatitis, you immediately destroy the cell wall. The naturally occurring binding chemical floats away, the hemoglobin breaks in half, and instead of transporting gases it tends to hold onto them.

Both the fledgling Burns Laboratories and the giant Baxter International have created synthetic chemicals that will hold the hemoglobin halves together outside the red blood cell.

This so-called cross-binding reagent accomplishes two goals at once. In their stuck-together form, the two hemoglobin halves are no longer toxic to the body, and they are also permanently bound in such a way that the protein retains its gas-exchanging ability.

These companies both plan to remove hemoglobin from donated human blood, sterilize it with heat, purify it, and bind it together with their proprietary chemicals. Since the hemoglobin is now floating in a harmless salt and water solution, the same solution can be injected into any patient regardless of blood type.

"With our technology, which allows us to chemically cross-link hemoglobin, now we have a pure solution of hemoglobin that has no cells in it," says Dr. Barry Burns, the founder of Burns Laboratories. "It's no problem anymore to sterilize."

Dr. Burns spotted his opportunity when he learned that an organic chemist at the University of Maryland Baltimore County campus already had been the co-recipient of a U.S. patent on a chemical compound that would make a blood substitute possible.

Working together under a state grant, Dr. Burns and UMBC scientist Dr. Ramachandra Hosmane say they have since found an even better organic chemical linking agent to accomplish the same task -- stabilizing the hemoglobin protein outside of the red blood cell.

Dr. Burns, through his Burns Laboratories Inc., has begun the arduous process of lining up enough investors to pay the big bills ahead. His first phase alone calls for an investment of $750,000. After using that to complete the first animal tests, he will be trying to raise much more -- a minimum of $25 million. To win Food and Drug Administration approval, he must first prove the product safe in animal tests, and then show its safety and effectiveness in two phases of human testing.

"We may be in a position to do phase-one human clinicals toward the end of this year, or early next year," said Dr. Burns. "We think we can complete our animal studies in approximately nine months. We have people lined up to do that work."

By entering the race, Dr. Burns has pitted himself against numerous competitors, some of whom have a serious head start. At least one company in the field, though, is looking to establish ties with a company such as Burns Laboratories -- someone who has a proprietary interest in a cross-linking reagent.

DNX Inc. of Princeton, N.J., raised $25 million in a public stock offering in December after learning how to get pigs to make human hemoglobin in their blood cells.

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