By Mary Welch

Alliance Pharmaceutical Corp. and the FDA reached an agreement on design of a Phase III trial of Oxygent, an intravascular oxygen carrier designed to reduce the use of donor blood transfusions in cardiac surgical patients.

The trial should start within the next "month or two," said Gwen Rosenberg, vice president of corporate communications for the San Diego-based company. "We've already had a pre-meeting with the principal investigators. We've already identified some sites and are selecting additional ones. There will be about 30 sites in the U.S., and maybe Canada."

Like blood, Oxygent carries oxygen to tissues through the bloodstream. But it does not contain any clotting factors or cells with immunologic function. In Phase II trials the perflubron-based emulsion was shown to be more effective in reversing transfusion "triggers" - physiological changes that indicate the need for more blood - and in delaying the need for a subsequent transfusion. (See BioWorld Today, Nov. 17, 1998, p. 1.)

Perflubron is derived from the same process used to make Teflon, Rosenberg said. "It's the only blood substitute in clinical development that is formulated from a synthetic raw material that is not derived from human or bovine blood."

The trial will involve about 600 patients, half of whom will be treated with Oxygent, the other 300 with Alliance's proprietary Augmented Acute Normovolemic Hemodilution (A-ANH) technology but not augmented with oxygen, which is standard care for pulmonary bypass patients.

"The emulsion looks like milk and has small particles of approximately 0.2 microns in diameter, which is more than an order of magnitude smaller than a red blood cell," Rosenberg said. "The particles are small enough to get around blockages where red blood cells can't pass and provide oxygen to the tissues. Another benefit of Oxygent is that is comes in a bottle - like a milk bottle - and is just hooked into the IV. It's a prepared solution as opposed to technicians having to mix things."

The trial will involve patients undergoing coronary artery bypass grafting surgery under cardiopulmonary bypass. It is expected to last one year. The study will complement one in Europe that is expected to wind up next summer. The European study involves patients undergoing general surgeries.

Unlike cardiovascular surgery where ANH that is not augmented with oxygen is the standard care, that is not the case with general surgery. In general surgery, the standard procedure is donor blood transfusion.

"In both trials, the endpoint is to reduce the number of blood transfusions used," she said.

The company expects to file in Europe for marketing clearance late next year and then file a supplementary document with the U.S. results. For a U.S. filling, data from both trials will be included.

Alliance is in talks with several partners for Oxygent, Rosenberg said.

In addition to Oxygent, Alliance has two other products in Phase III trials. Alliance plans on filing a new drug application for Imagent, an ultrasound contrast agent being developed with Schering AG, of Frankfurt, Germany. In addition, LiquiVent, an intrapulmonary liquid ventilation agent for the treatment of acute lung injury and acute respiratory distress syndrome, should finish up patient enrollment for its Phase III trials by mid-2000.

"It should be a very good year next year," Rosenberg said. "It just can't come fast enough."

Alliance's stock (NASDAQ:ALLP) closed Tuesday at $4.875, up 75 cents, or 18 percent.